xref: /petsc/src/mat/interface/matrix.c (revision 9596e0b48258fba4fca4f68feb5185896facfe69)
1 #define PETSCMAT_DLL
2 
3 /*
4    This is where the abstract matrix operations are defined
5 */
6 
7 #include "private/matimpl.h"        /*I "petscmat.h" I*/
8 #include "private/vecimpl.h"
9 
10 /* Logging support */
11 PetscCookie PETSCMAT_DLLEXPORT MAT_COOKIE;
12 PetscCookie PETSCMAT_DLLEXPORT MAT_FDCOLORING_COOKIE;
13 
14 PetscLogEvent  MAT_Mult, MAT_Mults, MAT_MultConstrained, MAT_MultAdd, MAT_MultTranspose;
15 PetscLogEvent  MAT_MultTransposeConstrained, MAT_MultTransposeAdd, MAT_Solve, MAT_Solves, MAT_SolveAdd, MAT_SolveTranspose, MAT_MatSolve;
16 PetscLogEvent  MAT_SolveTransposeAdd, MAT_Relax, MAT_ForwardSolve, MAT_BackwardSolve, MAT_LUFactor, MAT_LUFactorSymbolic;
17 PetscLogEvent  MAT_LUFactorNumeric, MAT_CholeskyFactor, MAT_CholeskyFactorSymbolic, MAT_CholeskyFactorNumeric, MAT_ILUFactor;
18 PetscLogEvent  MAT_ILUFactorSymbolic, MAT_ICCFactorSymbolic, MAT_Copy, MAT_Convert, MAT_Scale, MAT_AssemblyBegin;
19 PetscLogEvent  MAT_AssemblyEnd, MAT_SetValues, MAT_GetValues, MAT_GetRow, MAT_GetRowIJ, MAT_GetSubMatrices, MAT_GetColoring, MAT_GetOrdering, MAT_GetRedundantMatrix, MAT_GetSeqNonzeroStructure;
20 PetscLogEvent  MAT_IncreaseOverlap, MAT_Partitioning, MAT_ZeroEntries, MAT_Load, MAT_View, MAT_AXPY, MAT_FDColoringCreate;
21 PetscLogEvent  MAT_FDColoringApply,MAT_Transpose,MAT_FDColoringFunction;
22 PetscLogEvent  MAT_MatMult, MAT_MatMultSymbolic, MAT_MatMultNumeric;
23 PetscLogEvent  MAT_PtAP, MAT_PtAPSymbolic, MAT_PtAPNumeric;
24 PetscLogEvent  MAT_MatMultTranspose, MAT_MatMultTransposeSymbolic, MAT_MatMultTransposeNumeric;
25 PetscLogEvent  MAT_Getsymtranspose, MAT_Getsymtransreduced, MAT_Transpose_SeqAIJ, MAT_GetBrowsOfAcols;
26 PetscLogEvent  MAT_GetBrowsOfAocols, MAT_Getlocalmat, MAT_Getlocalmatcondensed, MAT_Seqstompi, MAT_Seqstompinum, MAT_Seqstompisym;
27 PetscLogEvent  MAT_Applypapt, MAT_Applypapt_numeric, MAT_Applypapt_symbolic, MAT_GetSequentialNonzeroStructure;
28 PetscLogEvent  MAT_ILUDTFactorSymbolic, MAT_ILUDTFactorNumeric;
29 
30 /* nasty global values for MatSetValue() */
31 PetscInt    PETSCMAT_DLLEXPORT MatSetValue_Row = 0;
32 PetscInt    PETSCMAT_DLLEXPORT MatSetValue_Column = 0;
33 PetscScalar PETSCMAT_DLLEXPORT MatSetValue_Value = 0.0;
34 
35 #undef __FUNCT__
36 #define __FUNCT__ "MatGetDiagonalBlock"
37 /*@
38    MatGetDiagonalBlock - Returns the part of the matrix associated with the on-process coupling
39 
40    Not Collective
41 
42    Input Parameters:
43 +  mat - the matrix
44 -  reuse - indicates you are passing in the a matrix and want it reused
45 
46    Output Parameters:
47 +   iscopy - indicates a copy of the diagonal matrix was created and you should use MatDestroy() on it
48 -   a - the diagonal part (which is a SEQUENTIAL matrix)
49 
50    Notes: see the manual page for MatCreateMPIAIJ() for more information on the "diagonal part" of the matrix
51 
52    Level: advanced
53 
54 @*/
55 PetscErrorCode PETSCMAT_DLLEXPORT MatGetDiagonalBlock(Mat A,PetscTruth *iscopy,MatReuse reuse,Mat *a)
56 {
57   PetscErrorCode ierr,(*f)(Mat,PetscTruth*,MatReuse,Mat*);
58   PetscMPIInt    size;
59 
60   PetscFunctionBegin;
61   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
62   PetscValidType(A,1);
63   PetscValidPointer(iscopy,2);
64   PetscValidPointer(a,3);
65   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
66   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
67   ierr = MPI_Comm_size(((PetscObject)A)->comm,&size);CHKERRQ(ierr);
68   ierr = PetscObjectQueryFunction((PetscObject)A,"MatGetDiagonalBlock_C",(void (**)(void))&f);CHKERRQ(ierr);
69   if (f) {
70     ierr = (*f)(A,iscopy,reuse,a);CHKERRQ(ierr);
71   } else if (size == 1) {
72     *a = A;
73     *iscopy = PETSC_FALSE;
74   } else {
75     SETERRQ(PETSC_ERR_SUP,"Cannot get diagonal part for this matrix");
76   }
77   PetscFunctionReturn(0);
78 }
79 
80 #undef __FUNCT__
81 #define __FUNCT__ "MatRealPart"
82 /*@
83    MatRealPart - Zeros out the imaginary part of the matrix
84 
85    Collective on Mat
86 
87    Input Parameters:
88 .  mat - the matrix
89 
90    Level: advanced
91 
92 
93 .seealso: MatImaginaryPart()
94 @*/
95 PetscErrorCode PETSCMAT_DLLEXPORT MatRealPart(Mat mat)
96 {
97   PetscErrorCode ierr;
98 
99   PetscFunctionBegin;
100   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
101   PetscValidType(mat,1);
102   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
103   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
104   if (!mat->ops->realpart) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
105   ierr = MatPreallocated(mat);CHKERRQ(ierr);
106   ierr = (*mat->ops->realpart)(mat);CHKERRQ(ierr);
107   PetscFunctionReturn(0);
108 }
109 
110 #undef __FUNCT__
111 #define __FUNCT__ "MatGetGhosts"
112 /*@C
113    MatGetGhosts - Get the global index of all ghost nodes defined by the sparse matrix
114 
115    Collective on Mat
116 
117    Input Parameter:
118 .  mat - the matrix
119 
120    Output Parameters:
121 +   nghosts - number of ghosts (note for BAIJ matrices there is one ghost for each block)
122 -   ghosts - the global indices of the ghost points
123 
124    Notes: the nghosts and ghosts are suitable to pass into VecCreateGhost()
125 
126    Level: advanced
127 
128 @*/
129 PetscErrorCode PETSCMAT_DLLEXPORT MatGetGhosts(Mat mat,PetscInt *nghosts,const PetscInt *ghosts[])
130 {
131   PetscErrorCode ierr;
132 
133   PetscFunctionBegin;
134   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
135   PetscValidType(mat,1);
136   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
137   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
138   if (!mat->ops->getghosts) {
139     if (nghosts) *nghosts = 0;
140     if (ghosts) *ghosts = 0;
141   } else {
142     ierr = (*mat->ops->getghosts)(mat,nghosts,ghosts);CHKERRQ(ierr);
143   }
144   PetscFunctionReturn(0);
145 }
146 
147 
148 #undef __FUNCT__
149 #define __FUNCT__ "MatImaginaryPart"
150 /*@
151    MatImaginaryPart - Moves the imaginary part of the matrix to the real part and zeros the imaginary part
152 
153    Collective on Mat
154 
155    Input Parameters:
156 .  mat - the matrix
157 
158    Level: advanced
159 
160 
161 .seealso: MatRealPart()
162 @*/
163 PetscErrorCode PETSCMAT_DLLEXPORT MatImaginaryPart(Mat mat)
164 {
165   PetscErrorCode ierr;
166 
167   PetscFunctionBegin;
168   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
169   PetscValidType(mat,1);
170   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
171   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
172   if (!mat->ops->imaginarypart) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
173   ierr = MatPreallocated(mat);CHKERRQ(ierr);
174   ierr = (*mat->ops->imaginarypart)(mat);CHKERRQ(ierr);
175   PetscFunctionReturn(0);
176 }
177 
178 #undef __FUNCT__
179 #define __FUNCT__ "MatMissingDiagonal"
180 /*@
181    MatMissingDiagonal - Determine if sparse matrix is missing a diagonal entry (or block entry for BAIJ matrices)
182 
183    Collective on Mat
184 
185    Input Parameter:
186 .  mat - the matrix
187 
188    Output Parameters:
189 +  missing - is any diagonal missing
190 -  dd - first diagonal entry that is missing (optional)
191 
192    Level: advanced
193 
194 
195 .seealso: MatRealPart()
196 @*/
197 PetscErrorCode PETSCMAT_DLLEXPORT MatMissingDiagonal(Mat mat,PetscTruth *missing,PetscInt *dd)
198 {
199   PetscErrorCode ierr;
200 
201   PetscFunctionBegin;
202   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
203   PetscValidType(mat,1);
204   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
205   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
206   if (!mat->ops->missingdiagonal) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
207   ierr = (*mat->ops->missingdiagonal)(mat,missing,dd);CHKERRQ(ierr);
208   PetscFunctionReturn(0);
209 }
210 
211 #undef __FUNCT__
212 #define __FUNCT__ "MatGetRow"
213 /*@C
214    MatGetRow - Gets a row of a matrix.  You MUST call MatRestoreRow()
215    for each row that you get to ensure that your application does
216    not bleed memory.
217 
218    Not Collective
219 
220    Input Parameters:
221 +  mat - the matrix
222 -  row - the row to get
223 
224    Output Parameters:
225 +  ncols -  if not NULL, the number of nonzeros in the row
226 .  cols - if not NULL, the column numbers
227 -  vals - if not NULL, the values
228 
229    Notes:
230    This routine is provided for people who need to have direct access
231    to the structure of a matrix.  We hope that we provide enough
232    high-level matrix routines that few users will need it.
233 
234    MatGetRow() always returns 0-based column indices, regardless of
235    whether the internal representation is 0-based (default) or 1-based.
236 
237    For better efficiency, set cols and/or vals to PETSC_NULL if you do
238    not wish to extract these quantities.
239 
240    The user can only examine the values extracted with MatGetRow();
241    the values cannot be altered.  To change the matrix entries, one
242    must use MatSetValues().
243 
244    You can only have one call to MatGetRow() outstanding for a particular
245    matrix at a time, per processor. MatGetRow() can only obtain rows
246    associated with the given processor, it cannot get rows from the
247    other processors; for that we suggest using MatGetSubMatrices(), then
248    MatGetRow() on the submatrix. The row indix passed to MatGetRows()
249    is in the global number of rows.
250 
251    Fortran Notes:
252    The calling sequence from Fortran is
253 .vb
254    MatGetRow(matrix,row,ncols,cols,values,ierr)
255          Mat     matrix (input)
256          integer row    (input)
257          integer ncols  (output)
258          integer cols(maxcols) (output)
259          double precision (or double complex) values(maxcols) output
260 .ve
261    where maxcols >= maximum nonzeros in any row of the matrix.
262 
263 
264    Caution:
265    Do not try to change the contents of the output arrays (cols and vals).
266    In some cases, this may corrupt the matrix.
267 
268    Level: advanced
269 
270    Concepts: matrices^row access
271 
272 .seealso: MatRestoreRow(), MatSetValues(), MatGetValues(), MatGetSubMatrices(), MatGetDiagonal()
273 @*/
274 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRow(Mat mat,PetscInt row,PetscInt *ncols,const PetscInt *cols[],const PetscScalar *vals[])
275 {
276   PetscErrorCode ierr;
277   PetscInt       incols;
278 
279   PetscFunctionBegin;
280   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
281   PetscValidType(mat,1);
282   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
283   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
284   if (!mat->ops->getrow) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
285   ierr = MatPreallocated(mat);CHKERRQ(ierr);
286   ierr = PetscLogEventBegin(MAT_GetRow,mat,0,0,0);CHKERRQ(ierr);
287   ierr = (*mat->ops->getrow)(mat,row,&incols,(PetscInt **)cols,(PetscScalar **)vals);CHKERRQ(ierr);
288   if (ncols) *ncols = incols;
289   ierr = PetscLogEventEnd(MAT_GetRow,mat,0,0,0);CHKERRQ(ierr);
290   PetscFunctionReturn(0);
291 }
292 
293 #undef __FUNCT__
294 #define __FUNCT__ "MatConjugate"
295 /*@
296    MatConjugate - replaces the matrix values with their complex conjugates
297 
298    Collective on Mat
299 
300    Input Parameters:
301 .  mat - the matrix
302 
303    Level: advanced
304 
305 .seealso:  VecConjugate()
306 @*/
307 PetscErrorCode PETSCMAT_DLLEXPORT MatConjugate(Mat mat)
308 {
309   PetscErrorCode ierr;
310 
311   PetscFunctionBegin;
312   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
313   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
314   if (!mat->ops->conjugate) SETERRQ(PETSC_ERR_SUP,"Not provided for this matrix format, send email to petsc-maint@mcs.anl.gov");
315   ierr = (*mat->ops->conjugate)(mat);CHKERRQ(ierr);
316   PetscFunctionReturn(0);
317 }
318 
319 #undef __FUNCT__
320 #define __FUNCT__ "MatRestoreRow"
321 /*@C
322    MatRestoreRow - Frees any temporary space allocated by MatGetRow().
323 
324    Not Collective
325 
326    Input Parameters:
327 +  mat - the matrix
328 .  row - the row to get
329 .  ncols, cols - the number of nonzeros and their columns
330 -  vals - if nonzero the column values
331 
332    Notes:
333    This routine should be called after you have finished examining the entries.
334 
335    Fortran Notes:
336    The calling sequence from Fortran is
337 .vb
338    MatRestoreRow(matrix,row,ncols,cols,values,ierr)
339       Mat     matrix (input)
340       integer row    (input)
341       integer ncols  (output)
342       integer cols(maxcols) (output)
343       double precision (or double complex) values(maxcols) output
344 .ve
345    Where maxcols >= maximum nonzeros in any row of the matrix.
346 
347    In Fortran MatRestoreRow() MUST be called after MatGetRow()
348    before another call to MatGetRow() can be made.
349 
350    Level: advanced
351 
352 .seealso:  MatGetRow()
353 @*/
354 PetscErrorCode PETSCMAT_DLLEXPORT MatRestoreRow(Mat mat,PetscInt row,PetscInt *ncols,const PetscInt *cols[],const PetscScalar *vals[])
355 {
356   PetscErrorCode ierr;
357 
358   PetscFunctionBegin;
359   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
360   PetscValidIntPointer(ncols,3);
361   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
362   if (!mat->ops->restorerow) PetscFunctionReturn(0);
363   ierr = (*mat->ops->restorerow)(mat,row,ncols,(PetscInt **)cols,(PetscScalar **)vals);CHKERRQ(ierr);
364   PetscFunctionReturn(0);
365 }
366 
367 #undef __FUNCT__
368 #define __FUNCT__ "MatGetRowUpperTriangular"
369 /*@
370    MatGetRowUpperTriangular - Sets a flag to enable calls to MatGetRow() for matrix in MATSBAIJ format.
371    You should call MatRestoreRowUpperTriangular() after calling MatGetRow/MatRestoreRow() to disable the flag.
372 
373    Not Collective
374 
375    Input Parameters:
376 +  mat - the matrix
377 
378    Notes:
379    The flag is to ensure that users are aware of MatGetRow() only provides the upper trianglular part of the row for the matrices in MATSBAIJ format.
380 
381    Level: advanced
382 
383    Concepts: matrices^row access
384 
385 .seealso: MatRestoreRowRowUpperTriangular()
386 @*/
387 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRowUpperTriangular(Mat mat)
388 {
389   PetscErrorCode ierr;
390 
391   PetscFunctionBegin;
392   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
393   PetscValidType(mat,1);
394   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
395   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
396   if (!mat->ops->getrowuppertriangular) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
397   ierr = MatPreallocated(mat);CHKERRQ(ierr);
398   ierr = (*mat->ops->getrowuppertriangular)(mat);CHKERRQ(ierr);
399   PetscFunctionReturn(0);
400 }
401 
402 #undef __FUNCT__
403 #define __FUNCT__ "MatRestoreRowUpperTriangular"
404 /*@
405    MatRestoreRowUpperTriangular - Disable calls to MatGetRow() for matrix in MATSBAIJ format.
406 
407    Not Collective
408 
409    Input Parameters:
410 +  mat - the matrix
411 
412    Notes:
413    This routine should be called after you have finished MatGetRow/MatRestoreRow().
414 
415 
416    Level: advanced
417 
418 .seealso:  MatGetRowUpperTriangular()
419 @*/
420 PetscErrorCode PETSCMAT_DLLEXPORT MatRestoreRowUpperTriangular(Mat mat)
421 {
422   PetscErrorCode ierr;
423 
424   PetscFunctionBegin;
425   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
426   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
427   if (!mat->ops->restorerowuppertriangular) PetscFunctionReturn(0);
428   ierr = (*mat->ops->restorerowuppertriangular)(mat);CHKERRQ(ierr);
429   PetscFunctionReturn(0);
430 }
431 
432 #undef __FUNCT__
433 #define __FUNCT__ "MatSetOptionsPrefix"
434 /*@C
435    MatSetOptionsPrefix - Sets the prefix used for searching for all
436    Mat options in the database.
437 
438    Collective on Mat
439 
440    Input Parameter:
441 +  A - the Mat context
442 -  prefix - the prefix to prepend to all option names
443 
444    Notes:
445    A hyphen (-) must NOT be given at the beginning of the prefix name.
446    The first character of all runtime options is AUTOMATICALLY the hyphen.
447 
448    Level: advanced
449 
450 .keywords: Mat, set, options, prefix, database
451 
452 .seealso: MatSetFromOptions()
453 @*/
454 PetscErrorCode PETSCMAT_DLLEXPORT MatSetOptionsPrefix(Mat A,const char prefix[])
455 {
456   PetscErrorCode ierr;
457 
458   PetscFunctionBegin;
459   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
460   ierr = PetscObjectSetOptionsPrefix((PetscObject)A,prefix);CHKERRQ(ierr);
461   PetscFunctionReturn(0);
462 }
463 
464 #undef __FUNCT__
465 #define __FUNCT__ "MatAppendOptionsPrefix"
466 /*@C
467    MatAppendOptionsPrefix - Appends to the prefix used for searching for all
468    Mat options in the database.
469 
470    Collective on Mat
471 
472    Input Parameters:
473 +  A - the Mat context
474 -  prefix - the prefix to prepend to all option names
475 
476    Notes:
477    A hyphen (-) must NOT be given at the beginning of the prefix name.
478    The first character of all runtime options is AUTOMATICALLY the hyphen.
479 
480    Level: advanced
481 
482 .keywords: Mat, append, options, prefix, database
483 
484 .seealso: MatGetOptionsPrefix()
485 @*/
486 PetscErrorCode PETSCMAT_DLLEXPORT MatAppendOptionsPrefix(Mat A,const char prefix[])
487 {
488   PetscErrorCode ierr;
489 
490   PetscFunctionBegin;
491   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
492   ierr = PetscObjectAppendOptionsPrefix((PetscObject)A,prefix);CHKERRQ(ierr);
493   PetscFunctionReturn(0);
494 }
495 
496 #undef __FUNCT__
497 #define __FUNCT__ "MatGetOptionsPrefix"
498 /*@C
499    MatGetOptionsPrefix - Sets the prefix used for searching for all
500    Mat options in the database.
501 
502    Not Collective
503 
504    Input Parameter:
505 .  A - the Mat context
506 
507    Output Parameter:
508 .  prefix - pointer to the prefix string used
509 
510    Notes: On the fortran side, the user should pass in a string 'prefix' of
511    sufficient length to hold the prefix.
512 
513    Level: advanced
514 
515 .keywords: Mat, get, options, prefix, database
516 
517 .seealso: MatAppendOptionsPrefix()
518 @*/
519 PetscErrorCode PETSCMAT_DLLEXPORT MatGetOptionsPrefix(Mat A,const char *prefix[])
520 {
521   PetscErrorCode ierr;
522 
523   PetscFunctionBegin;
524   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
525   ierr = PetscObjectGetOptionsPrefix((PetscObject)A,prefix);CHKERRQ(ierr);
526   PetscFunctionReturn(0);
527 }
528 
529 #undef __FUNCT__
530 #define __FUNCT__ "MatSetUp"
531 /*@
532    MatSetUp - Sets up the internal matrix data structures for the later use.
533 
534    Collective on Mat
535 
536    Input Parameters:
537 .  A - the Mat context
538 
539    Notes:
540    For basic use of the Mat classes the user need not explicitly call
541    MatSetUp(), since these actions will happen automatically.
542 
543    Level: advanced
544 
545 .keywords: Mat, setup
546 
547 .seealso: MatCreate(), MatDestroy()
548 @*/
549 PetscErrorCode PETSCMAT_DLLEXPORT MatSetUp(Mat A)
550 {
551   PetscMPIInt    size;
552   PetscErrorCode ierr;
553 
554   PetscFunctionBegin;
555   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
556   if (!((PetscObject)A)->type_name) {
557     ierr = MPI_Comm_size(((PetscObject)A)->comm, &size);CHKERRQ(ierr);
558     if (size == 1) {
559       ierr = MatSetType(A, MATSEQAIJ);CHKERRQ(ierr);
560     } else {
561       ierr = MatSetType(A, MATMPIAIJ);CHKERRQ(ierr);
562     }
563   }
564   ierr = MatSetUpPreallocation(A);CHKERRQ(ierr);
565   PetscFunctionReturn(0);
566 }
567 
568 #undef __FUNCT__
569 #define __FUNCT__ "MatView"
570 /*@C
571    MatView - Visualizes a matrix object.
572 
573    Collective on Mat
574 
575    Input Parameters:
576 +  mat - the matrix
577 -  viewer - visualization context
578 
579   Notes:
580   The available visualization contexts include
581 +    PETSC_VIEWER_STDOUT_SELF - standard output (default)
582 .    PETSC_VIEWER_STDOUT_WORLD - synchronized standard
583         output where only the first processor opens
584         the file.  All other processors send their
585         data to the first processor to print.
586 -     PETSC_VIEWER_DRAW_WORLD - graphical display of nonzero structure
587 
588    The user can open alternative visualization contexts with
589 +    PetscViewerASCIIOpen() - Outputs matrix to a specified file
590 .    PetscViewerBinaryOpen() - Outputs matrix in binary to a
591          specified file; corresponding input uses MatLoad()
592 .    PetscViewerDrawOpen() - Outputs nonzero matrix structure to
593          an X window display
594 -    PetscViewerSocketOpen() - Outputs matrix to Socket viewer.
595          Currently only the sequential dense and AIJ
596          matrix types support the Socket viewer.
597 
598    The user can call PetscViewerSetFormat() to specify the output
599    format of ASCII printed objects (when using PETSC_VIEWER_STDOUT_SELF,
600    PETSC_VIEWER_STDOUT_WORLD and PetscViewerASCIIOpen).  Available formats include
601 +    PETSC_VIEWER_DEFAULT - default, prints matrix contents
602 .    PETSC_VIEWER_ASCII_MATLAB - prints matrix contents in Matlab format
603 .    PETSC_VIEWER_ASCII_DENSE - prints entire matrix including zeros
604 .    PETSC_VIEWER_ASCII_COMMON - prints matrix contents, using a sparse
605          format common among all matrix types
606 .    PETSC_VIEWER_ASCII_IMPL - prints matrix contents, using an implementation-specific
607          format (which is in many cases the same as the default)
608 .    PETSC_VIEWER_ASCII_INFO - prints basic information about the matrix
609          size and structure (not the matrix entries)
610 .    PETSC_VIEWER_ASCII_INFO_DETAIL - prints more detailed information about
611          the matrix structure
612 
613    Options Database Keys:
614 +  -mat_view_info - Prints info on matrix at conclusion of MatEndAssembly()
615 .  -mat_view_info_detailed - Prints more detailed info
616 .  -mat_view - Prints matrix in ASCII format
617 .  -mat_view_matlab - Prints matrix in Matlab format
618 .  -mat_view_draw - PetscDraws nonzero structure of matrix, using MatView() and PetscDrawOpenX().
619 .  -display <name> - Sets display name (default is host)
620 .  -draw_pause <sec> - Sets number of seconds to pause after display
621 .  -mat_view_socket - Sends matrix to socket, can be accessed from Matlab (see users manual)
622 .  -viewer_socket_machine <machine>
623 .  -viewer_socket_port <port>
624 .  -mat_view_binary - save matrix to file in binary format
625 -  -viewer_binary_filename <name>
626    Level: beginner
627 
628    Notes: see the manual page for MatLoad() for the exact format of the binary file when the binary
629       viewer is used.
630 
631       See bin/matlab/PetscBinaryRead.m for a Matlab code that can read in the binary file when the binary
632       viewer is used.
633 
634    Concepts: matrices^viewing
635    Concepts: matrices^plotting
636    Concepts: matrices^printing
637 
638 .seealso: PetscViewerSetFormat(), PetscViewerASCIIOpen(), PetscViewerDrawOpen(),
639           PetscViewerSocketOpen(), PetscViewerBinaryOpen(), MatLoad()
640 @*/
641 PetscErrorCode PETSCMAT_DLLEXPORT MatView(Mat mat,PetscViewer viewer)
642 {
643   PetscErrorCode    ierr;
644   PetscInt          rows,cols;
645   PetscTruth        iascii;
646   const MatType     cstr;
647   PetscViewerFormat format;
648 
649   PetscFunctionBegin;
650   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
651   PetscValidType(mat,1);
652   if (!viewer) {
653     ierr = PetscViewerASCIIGetStdout(((PetscObject)mat)->comm,&viewer);CHKERRQ(ierr);
654   }
655   PetscValidHeaderSpecific(viewer,PETSC_VIEWER_COOKIE,2);
656   PetscCheckSameComm(mat,1,viewer,2);
657   if (!mat->assembled) SETERRQ(PETSC_ERR_ORDER,"Must call MatAssemblyBegin/End() before viewing matrix");
658   ierr = MatPreallocated(mat);CHKERRQ(ierr);
659 
660   ierr = PetscLogEventBegin(MAT_View,mat,viewer,0,0);CHKERRQ(ierr);
661   ierr = PetscTypeCompare((PetscObject)viewer,PETSC_VIEWER_ASCII,&iascii);CHKERRQ(ierr);
662   if (iascii) {
663     ierr = PetscViewerGetFormat(viewer,&format);CHKERRQ(ierr);
664     if (format == PETSC_VIEWER_ASCII_INFO || format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
665       if (((PetscObject)mat)->prefix) {
666         ierr = PetscViewerASCIIPrintf(viewer,"Matrix Object:(%s)\n",((PetscObject)mat)->prefix);CHKERRQ(ierr);
667       } else {
668         ierr = PetscViewerASCIIPrintf(viewer,"Matrix Object:\n");CHKERRQ(ierr);
669       }
670       ierr = PetscViewerASCIIPushTab(viewer);CHKERRQ(ierr);
671       ierr = MatGetType(mat,&cstr);CHKERRQ(ierr);
672       ierr = MatGetSize(mat,&rows,&cols);CHKERRQ(ierr);
673       ierr = PetscViewerASCIIPrintf(viewer,"type=%s, rows=%D, cols=%D\n",cstr,rows,cols);CHKERRQ(ierr);
674       if (mat->factor) {
675         const MatSolverPackage solver;
676         ierr = MatFactorGetSolverPackage(mat,&solver);CHKERRQ(ierr);
677         ierr = PetscViewerASCIIPrintf(viewer,"package used to perform factorization: %s\n",solver);CHKERRQ(ierr);
678       }
679       if (mat->ops->getinfo) {
680         MatInfo info;
681         ierr = MatGetInfo(mat,MAT_GLOBAL_SUM,&info);CHKERRQ(ierr);
682         ierr = PetscViewerASCIIPrintf(viewer,"total: nonzeros=%D, allocated nonzeros=%D\n",(PetscInt)info.nz_used,(PetscInt)info.nz_allocated);CHKERRQ(ierr);
683       }
684     }
685   }
686   if (mat->ops->view) {
687     ierr = PetscViewerASCIIPushTab(viewer);CHKERRQ(ierr);
688     ierr = (*mat->ops->view)(mat,viewer);CHKERRQ(ierr);
689     ierr = PetscViewerASCIIPopTab(viewer);CHKERRQ(ierr);
690   } else if (!iascii) {
691     SETERRQ1(PETSC_ERR_SUP,"Viewer type %s not supported",((PetscObject)viewer)->type_name);
692   }
693   if (iascii) {
694     ierr = PetscViewerGetFormat(viewer,&format);CHKERRQ(ierr);
695     if (format == PETSC_VIEWER_ASCII_INFO || format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
696       ierr = PetscViewerASCIIPopTab(viewer);CHKERRQ(ierr);
697     }
698   }
699   ierr = PetscLogEventEnd(MAT_View,mat,viewer,0,0);CHKERRQ(ierr);
700   PetscFunctionReturn(0);
701 }
702 
703 #undef __FUNCT__
704 #define __FUNCT__ "MatScaleSystem"
705 /*@
706    MatScaleSystem - Scale a vector solution and right hand side to
707    match the scaling of a scaled matrix.
708 
709    Collective on Mat
710 
711    Input Parameter:
712 +  mat - the matrix
713 .  b - right hand side vector (or PETSC_NULL)
714 -  x - solution vector (or PETSC_NULL)
715 
716 
717    Notes:
718    For AIJ, and BAIJ matrix formats, the matrices are not
719    internally scaled, so this does nothing. For MPIROWBS it
720    permutes and diagonally scales.
721 
722    The KSP methods automatically call this routine when required
723    (via PCPreSolve()) so it is rarely used directly.
724 
725    Level: Developer
726 
727    Concepts: matrices^scaling
728 
729 .seealso: MatUseScaledForm(), MatUnScaleSystem()
730 @*/
731 PetscErrorCode PETSCMAT_DLLEXPORT MatScaleSystem(Mat mat,Vec b,Vec x)
732 {
733   PetscErrorCode ierr;
734 
735   PetscFunctionBegin;
736   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
737   PetscValidType(mat,1);
738   ierr = MatPreallocated(mat);CHKERRQ(ierr);
739   if (x) {PetscValidHeaderSpecific(x,VEC_COOKIE,2);PetscCheckSameComm(mat,1,x,2);}
740   if (b) {PetscValidHeaderSpecific(b,VEC_COOKIE,3);PetscCheckSameComm(mat,1,b,3);}
741 
742   if (mat->ops->scalesystem) {
743     ierr = (*mat->ops->scalesystem)(mat,b,x);CHKERRQ(ierr);
744   }
745   PetscFunctionReturn(0);
746 }
747 
748 #undef __FUNCT__
749 #define __FUNCT__ "MatUnScaleSystem"
750 /*@
751    MatUnScaleSystem - Unscales a vector solution and right hand side to
752    match the original scaling of a scaled matrix.
753 
754    Collective on Mat
755 
756    Input Parameter:
757 +  mat - the matrix
758 .  b - right hand side vector (or PETSC_NULL)
759 -  x - solution vector (or PETSC_NULL)
760 
761 
762    Notes:
763    For AIJ and BAIJ matrix formats, the matrices are not
764    internally scaled, so this does nothing. For MPIROWBS it
765    permutes and diagonally scales.
766 
767    The KSP methods automatically call this routine when required
768    (via PCPreSolve()) so it is rarely used directly.
769 
770    Level: Developer
771 
772 .seealso: MatUseScaledForm(), MatScaleSystem()
773 @*/
774 PetscErrorCode PETSCMAT_DLLEXPORT MatUnScaleSystem(Mat mat,Vec b,Vec x)
775 {
776   PetscErrorCode ierr;
777 
778   PetscFunctionBegin;
779   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
780   PetscValidType(mat,1);
781   ierr = MatPreallocated(mat);CHKERRQ(ierr);
782   if (x) {PetscValidHeaderSpecific(x,VEC_COOKIE,2);PetscCheckSameComm(mat,1,x,2);}
783   if (b) {PetscValidHeaderSpecific(b,VEC_COOKIE,3);PetscCheckSameComm(mat,1,b,3);}
784   if (mat->ops->unscalesystem) {
785     ierr = (*mat->ops->unscalesystem)(mat,b,x);CHKERRQ(ierr);
786   }
787   PetscFunctionReturn(0);
788 }
789 
790 #undef __FUNCT__
791 #define __FUNCT__ "MatUseScaledForm"
792 /*@
793    MatUseScaledForm - For matrix storage formats that scale the
794    matrix (for example MPIRowBS matrices are diagonally scaled on
795    assembly) indicates matrix operations (MatMult() etc) are
796    applied using the scaled matrix.
797 
798    Collective on Mat
799 
800    Input Parameter:
801 +  mat - the matrix
802 -  scaled - PETSC_TRUE for applying the scaled, PETSC_FALSE for
803             applying the original matrix
804 
805    Notes:
806    For scaled matrix formats, applying the original, unscaled matrix
807    will be slightly more expensive
808 
809    Level: Developer
810 
811 .seealso: MatScaleSystem(), MatUnScaleSystem()
812 @*/
813 PetscErrorCode PETSCMAT_DLLEXPORT MatUseScaledForm(Mat mat,PetscTruth scaled)
814 {
815   PetscErrorCode ierr;
816 
817   PetscFunctionBegin;
818   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
819   PetscValidType(mat,1);
820   ierr = MatPreallocated(mat);CHKERRQ(ierr);
821   if (mat->ops->usescaledform) {
822     ierr = (*mat->ops->usescaledform)(mat,scaled);CHKERRQ(ierr);
823   }
824   PetscFunctionReturn(0);
825 }
826 
827 #undef __FUNCT__
828 #define __FUNCT__ "MatDestroy"
829 /*@
830    MatDestroy - Frees space taken by a matrix.
831 
832    Collective on Mat
833 
834    Input Parameter:
835 .  A - the matrix
836 
837    Level: beginner
838 
839 @*/
840 PetscErrorCode PETSCMAT_DLLEXPORT MatDestroy(Mat A)
841 {
842   PetscErrorCode ierr;
843   PetscFunctionBegin;
844   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
845   if (--((PetscObject)A)->refct > 0) PetscFunctionReturn(0);
846   ierr = MatPreallocated(A);CHKERRQ(ierr);
847   /* if memory was published with AMS then destroy it */
848   ierr = PetscObjectDepublish(A);CHKERRQ(ierr);
849   if (A->ops->destroy) {
850     ierr = (*A->ops->destroy)(A);CHKERRQ(ierr);
851   }
852   if (A->mapping) {
853     ierr = ISLocalToGlobalMappingDestroy(A->mapping);CHKERRQ(ierr);
854   }
855   if (A->bmapping) {
856     ierr = ISLocalToGlobalMappingDestroy(A->bmapping);CHKERRQ(ierr);
857   }
858 
859   if (A->spptr){ierr = PetscFree(A->spptr);CHKERRQ(ierr);}
860   ierr = PetscMapDestroy(A->rmap);CHKERRQ(ierr);
861   ierr = PetscMapDestroy(A->cmap);CHKERRQ(ierr);
862   ierr = PetscHeaderDestroy(A);CHKERRQ(ierr);
863   PetscFunctionReturn(0);
864 }
865 
866 #undef __FUNCT__
867 #define __FUNCT__ "MatValid"
868 /*@
869    MatValid - Checks whether a matrix object is valid.
870 
871    Collective on Mat
872 
873    Input Parameter:
874 .  m - the matrix to check
875 
876    Output Parameter:
877    flg - flag indicating matrix status, either
878    PETSC_TRUE if matrix is valid, or PETSC_FALSE otherwise.
879 
880    Level: developer
881 
882    Concepts: matrices^validity
883 @*/
884 PetscErrorCode PETSCMAT_DLLEXPORT MatValid(Mat m,PetscTruth *flg)
885 {
886   PetscFunctionBegin;
887   PetscValidIntPointer(flg,1);
888   if (!m)                                          *flg = PETSC_FALSE;
889   else if (((PetscObject)m)->cookie != MAT_COOKIE) *flg = PETSC_FALSE;
890   else                                             *flg = PETSC_TRUE;
891   PetscFunctionReturn(0);
892 }
893 
894 #undef __FUNCT__
895 #define __FUNCT__ "MatSetValues"
896 /*@
897    MatSetValues - Inserts or adds a block of values into a matrix.
898    These values may be cached, so MatAssemblyBegin() and MatAssemblyEnd()
899    MUST be called after all calls to MatSetValues() have been completed.
900 
901    Not Collective
902 
903    Input Parameters:
904 +  mat - the matrix
905 .  v - a logically two-dimensional array of values
906 .  m, idxm - the number of rows and their global indices
907 .  n, idxn - the number of columns and their global indices
908 -  addv - either ADD_VALUES or INSERT_VALUES, where
909    ADD_VALUES adds values to any existing entries, and
910    INSERT_VALUES replaces existing entries with new values
911 
912    Notes:
913    By default the values, v, are row-oriented and unsorted.
914    See MatSetOption() for other options.
915 
916    Calls to MatSetValues() with the INSERT_VALUES and ADD_VALUES
917    options cannot be mixed without intervening calls to the assembly
918    routines.
919 
920    MatSetValues() uses 0-based row and column numbers in Fortran
921    as well as in C.
922 
923    Negative indices may be passed in idxm and idxn, these rows and columns are
924    simply ignored. This allows easily inserting element stiffness matrices
925    with homogeneous Dirchlet boundary conditions that you don't want represented
926    in the matrix.
927 
928    Efficiency Alert:
929    The routine MatSetValuesBlocked() may offer much better efficiency
930    for users of block sparse formats (MATSEQBAIJ and MATMPIBAIJ).
931 
932    Level: beginner
933 
934    Concepts: matrices^putting entries in
935 
936 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal(),
937           InsertMode, INSERT_VALUES, ADD_VALUES
938 @*/
939 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValues(Mat mat,PetscInt m,const PetscInt idxm[],PetscInt n,const PetscInt idxn[],const PetscScalar v[],InsertMode addv)
940 {
941   PetscErrorCode ierr;
942 
943   PetscFunctionBegin;
944   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
945   PetscValidType(mat,1);
946   if (!m || !n) PetscFunctionReturn(0); /* no values to insert */
947   PetscValidIntPointer(idxm,3);
948   PetscValidIntPointer(idxn,5);
949   ierr = MatPreallocated(mat);CHKERRQ(ierr);
950   if (mat->insertmode == NOT_SET_VALUES) {
951     mat->insertmode = addv;
952   }
953 #if defined(PETSC_USE_DEBUG)
954   else if (mat->insertmode != addv) {
955     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
956   }
957   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
958 #endif
959 
960   if (mat->assembled) {
961     mat->was_assembled = PETSC_TRUE;
962     mat->assembled     = PETSC_FALSE;
963   }
964   ierr = PetscLogEventBegin(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
965   if (!mat->ops->setvalues) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
966   ierr = (*mat->ops->setvalues)(mat,m,idxm,n,idxn,v,addv);CHKERRQ(ierr);
967   ierr = PetscLogEventEnd(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
968   PetscFunctionReturn(0);
969 }
970 
971 
972 #undef __FUNCT__
973 #define __FUNCT__ "MatSetValuesRowLocal"
974 /*@
975    MatSetValuesRowLocal - Inserts a row (block row for BAIJ matrices) of nonzero
976         values into a matrix
977 
978    Not Collective
979 
980    Input Parameters:
981 +  mat - the matrix
982 .  row - the (block) row to set
983 -  v - a logically two-dimensional array of values
984 
985    Notes:
986    By the values, v, are column-oriented (for the block version) and sorted
987 
988    All the nonzeros in the row must be provided
989 
990    The matrix must have previously had its column indices set
991 
992    The row must belong to this process
993 
994    Level: intermediate
995 
996    Concepts: matrices^putting entries in
997 
998 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal(),
999           InsertMode, INSERT_VALUES, ADD_VALUES, MatSetValues(), MatSetValuesRow(), MatSetLocalToGlobalMapping()
1000 @*/
1001 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesRowLocal(Mat mat,PetscInt row,const PetscScalar v[])
1002 {
1003   PetscErrorCode ierr;
1004 
1005   PetscFunctionBegin;
1006   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1007   PetscValidType(mat,1);
1008   PetscValidScalarPointer(v,2);
1009   ierr = MatSetValuesRow(mat, mat->mapping->indices[row],v);CHKERRQ(ierr);
1010   PetscFunctionReturn(0);
1011 }
1012 
1013 #undef __FUNCT__
1014 #define __FUNCT__ "MatSetValuesRow"
1015 /*@
1016    MatSetValuesRow - Inserts a row (block row for BAIJ matrices) of nonzero
1017         values into a matrix
1018 
1019    Not Collective
1020 
1021    Input Parameters:
1022 +  mat - the matrix
1023 .  row - the (block) row to set
1024 -  v - a logically two-dimensional array of values
1025 
1026    Notes:
1027    By the values, v, are column-oriented (for the block version) and sorted
1028 
1029    All the nonzeros in the row must be provided
1030 
1031    The matrix must have previously had its column indices set
1032 
1033    The row must belong to this process
1034 
1035    Level: intermediate
1036 
1037    Concepts: matrices^putting entries in
1038 
1039 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal(),
1040           InsertMode, INSERT_VALUES, ADD_VALUES, MatSetValues()
1041 @*/
1042 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesRow(Mat mat,PetscInt row,const PetscScalar v[])
1043 {
1044   PetscErrorCode ierr;
1045 
1046   PetscFunctionBegin;
1047   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1048   PetscValidType(mat,1);
1049   PetscValidScalarPointer(v,2);
1050 #if defined(PETSC_USE_DEBUG)
1051   if (mat->insertmode == ADD_VALUES) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add and insert values");
1052   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1053 #endif
1054   mat->insertmode = INSERT_VALUES;
1055 
1056   if (mat->assembled) {
1057     mat->was_assembled = PETSC_TRUE;
1058     mat->assembled     = PETSC_FALSE;
1059   }
1060   ierr = PetscLogEventBegin(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
1061   if (!mat->ops->setvaluesrow) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
1062   ierr = (*mat->ops->setvaluesrow)(mat,row,v);CHKERRQ(ierr);
1063   ierr = PetscLogEventEnd(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
1064   PetscFunctionReturn(0);
1065 }
1066 
1067 #undef __FUNCT__
1068 #define __FUNCT__ "MatSetValuesStencil"
1069 /*@
1070    MatSetValuesStencil - Inserts or adds a block of values into a matrix.
1071      Using structured grid indexing
1072 
1073    Not Collective
1074 
1075    Input Parameters:
1076 +  mat - the matrix
1077 .  m - number of rows being entered
1078 .  idxm - grid coordinates (and component number when dof > 1) for matrix rows being entered
1079 .  n - number of columns being entered
1080 .  idxn - grid coordinates (and component number when dof > 1) for matrix columns being entered
1081 .  v - a logically two-dimensional array of values
1082 -  addv - either ADD_VALUES or INSERT_VALUES, where
1083    ADD_VALUES adds values to any existing entries, and
1084    INSERT_VALUES replaces existing entries with new values
1085 
1086    Notes:
1087    By default the values, v, are row-oriented.  See MatSetOption() for other options.
1088 
1089    Calls to MatSetValuesStencil() with the INSERT_VALUES and ADD_VALUES
1090    options cannot be mixed without intervening calls to the assembly
1091    routines.
1092 
1093    The grid coordinates are across the entire grid, not just the local portion
1094 
1095    MatSetValuesStencil() uses 0-based row and column numbers in Fortran
1096    as well as in C.
1097 
1098    For setting/accessing vector values via array coordinates you can use the DAVecGetArray() routine
1099 
1100    In order to use this routine you must either obtain the matrix with DAGetMatrix()
1101    or call MatSetLocalToGlobalMapping() and MatSetStencil() first.
1102 
1103    The columns and rows in the stencil passed in MUST be contained within the
1104    ghost region of the given process as set with DACreateXXX() or MatSetStencil(). For example,
1105    if you create a DA with an overlap of one grid level and on a particular process its first
1106    local nonghost x logical coordinate is 6 (so its first ghost x logical coordinate is 5) the
1107    first i index you can use in your column and row indices in MatSetStencil() is 5.
1108 
1109    In Fortran idxm and idxn should be declared as
1110 $     MatStencil idxm(4,m),idxn(4,n)
1111    and the values inserted using
1112 $    idxm(MatStencil_i,1) = i
1113 $    idxm(MatStencil_j,1) = j
1114 $    idxm(MatStencil_k,1) = k
1115 $    idxm(MatStencil_c,1) = c
1116    etc
1117 
1118    For periodic boundary conditions use negative indices for values to the left (below 0; that are to be
1119    obtained by wrapping values from right edge). For values to the right of the last entry using that index plus one
1120    etc to obtain values that obtained by wrapping the values from the left edge. This does not work for the DA_NONPERIODIC
1121    wrap.
1122 
1123    For indices that don't mean anything for your case (like the k index when working in 2d) or the c index when you have
1124    a single value per point) you can skip filling those indices.
1125 
1126    Inspired by the structured grid interface to the HYPRE package
1127    (http://www.llnl.gov/CASC/hypre)
1128 
1129    Efficiency Alert:
1130    The routine MatSetValuesBlockedStencil() may offer much better efficiency
1131    for users of block sparse formats (MATSEQBAIJ and MATMPIBAIJ).
1132 
1133    Level: beginner
1134 
1135    Concepts: matrices^putting entries in
1136 
1137 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal()
1138           MatSetValues(), MatSetValuesBlockedStencil(), MatSetStencil(), DAGetMatrix(), DAVecGetArray(), MatStencil
1139 @*/
1140 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesStencil(Mat mat,PetscInt m,const MatStencil idxm[],PetscInt n,const MatStencil idxn[],const PetscScalar v[],InsertMode addv)
1141 {
1142   PetscErrorCode ierr;
1143   PetscInt       j,i,jdxm[128],jdxn[256],dim = mat->stencil.dim,*dims = mat->stencil.dims+1,tmp;
1144   PetscInt       *starts = mat->stencil.starts,*dxm = (PetscInt*)idxm,*dxn = (PetscInt*)idxn,sdim = dim - (1 - (PetscInt)mat->stencil.noc);
1145 
1146   PetscFunctionBegin;
1147   if (!m || !n) PetscFunctionReturn(0); /* no values to insert */
1148   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1149   PetscValidType(mat,1);
1150   PetscValidIntPointer(idxm,3);
1151   PetscValidIntPointer(idxn,5);
1152   PetscValidScalarPointer(v,6);
1153 
1154   if (m > 128) SETERRQ1(PETSC_ERR_SUP,"Can only set 128 rows at a time; trying to set %D",m);
1155   if (n > 256) SETERRQ1(PETSC_ERR_SUP,"Can only set 256 columns at a time; trying to set %D",n);
1156 
1157   for (i=0; i<m; i++) {
1158     for (j=0; j<3-sdim; j++) dxm++;
1159     tmp = *dxm++ - starts[0];
1160     for (j=0; j<dim-1; j++) {
1161       if ((*dxm++ - starts[j+1]) < 0 || tmp < 0) tmp = PETSC_MIN_INT;
1162       else                                       tmp = tmp*dims[j] + *(dxm-1) - starts[j+1];
1163     }
1164     if (mat->stencil.noc) dxm++;
1165     jdxm[i] = tmp;
1166   }
1167   for (i=0; i<n; i++) {
1168     for (j=0; j<3-sdim; j++) dxn++;
1169     tmp = *dxn++ - starts[0];
1170     for (j=0; j<dim-1; j++) {
1171       if ((*dxn++ - starts[j+1]) < 0 || tmp < 0) tmp = PETSC_MIN_INT;
1172       else                                       tmp = tmp*dims[j] + *(dxn-1) - starts[j+1];
1173     }
1174     if (mat->stencil.noc) dxn++;
1175     jdxn[i] = tmp;
1176   }
1177   ierr = MatSetValuesLocal(mat,m,jdxm,n,jdxn,v,addv);CHKERRQ(ierr);
1178   PetscFunctionReturn(0);
1179 }
1180 
1181 #undef __FUNCT__
1182 #define __FUNCT__ "MatSetValuesBlockedStencil"
1183 /*@C
1184    MatSetValuesBlockedStencil - Inserts or adds a block of values into a matrix.
1185      Using structured grid indexing
1186 
1187    Not Collective
1188 
1189    Input Parameters:
1190 +  mat - the matrix
1191 .  m - number of rows being entered
1192 .  idxm - grid coordinates for matrix rows being entered
1193 .  n - number of columns being entered
1194 .  idxn - grid coordinates for matrix columns being entered
1195 .  v - a logically two-dimensional array of values
1196 -  addv - either ADD_VALUES or INSERT_VALUES, where
1197    ADD_VALUES adds values to any existing entries, and
1198    INSERT_VALUES replaces existing entries with new values
1199 
1200    Notes:
1201    By default the values, v, are row-oriented and unsorted.
1202    See MatSetOption() for other options.
1203 
1204    Calls to MatSetValuesBlockedStencil() with the INSERT_VALUES and ADD_VALUES
1205    options cannot be mixed without intervening calls to the assembly
1206    routines.
1207 
1208    The grid coordinates are across the entire grid, not just the local portion
1209 
1210    MatSetValuesBlockedStencil() uses 0-based row and column numbers in Fortran
1211    as well as in C.
1212 
1213    For setting/accessing vector values via array coordinates you can use the DAVecGetArray() routine
1214 
1215    In order to use this routine you must either obtain the matrix with DAGetMatrix()
1216    or call MatSetBlockSize(), MatSetLocalToGlobalMapping() and MatSetStencil() first.
1217 
1218    The columns and rows in the stencil passed in MUST be contained within the
1219    ghost region of the given process as set with DACreateXXX() or MatSetStencil(). For example,
1220    if you create a DA with an overlap of one grid level and on a particular process its first
1221    local nonghost x logical coordinate is 6 (so its first ghost x logical coordinate is 5) the
1222    first i index you can use in your column and row indices in MatSetStencil() is 5.
1223 
1224    In Fortran idxm and idxn should be declared as
1225 $     MatStencil idxm(4,m),idxn(4,n)
1226    and the values inserted using
1227 $    idxm(MatStencil_i,1) = i
1228 $    idxm(MatStencil_j,1) = j
1229 $    idxm(MatStencil_k,1) = k
1230    etc
1231 
1232    Negative indices may be passed in idxm and idxn, these rows and columns are
1233    simply ignored. This allows easily inserting element stiffness matrices
1234    with homogeneous Dirchlet boundary conditions that you don't want represented
1235    in the matrix.
1236 
1237    Inspired by the structured grid interface to the HYPRE package
1238    (http://www.llnl.gov/CASC/hypre)
1239 
1240    Level: beginner
1241 
1242    Concepts: matrices^putting entries in
1243 
1244 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal()
1245           MatSetValues(), MatSetValuesStencil(), MatSetStencil(), DAGetMatrix(), DAVecGetArray(), MatStencil,
1246           MatSetBlockSize(), MatSetLocalToGlobalMapping()
1247 @*/
1248 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesBlockedStencil(Mat mat,PetscInt m,const MatStencil idxm[],PetscInt n,const MatStencil idxn[],const PetscScalar v[],InsertMode addv)
1249 {
1250   PetscErrorCode ierr;
1251   PetscInt       j,i,jdxm[128],jdxn[256],dim = mat->stencil.dim,*dims = mat->stencil.dims+1,tmp;
1252   PetscInt       *starts = mat->stencil.starts,*dxm = (PetscInt*)idxm,*dxn = (PetscInt*)idxn,sdim = dim - (1 - (PetscInt)mat->stencil.noc);
1253 
1254   PetscFunctionBegin;
1255   if (!m || !n) PetscFunctionReturn(0); /* no values to insert */
1256   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1257   PetscValidType(mat,1);
1258   PetscValidIntPointer(idxm,3);
1259   PetscValidIntPointer(idxn,5);
1260   PetscValidScalarPointer(v,6);
1261 
1262   if (m > 128) SETERRQ1(PETSC_ERR_SUP,"Can only set 128 rows at a time; trying to set %D",m);
1263   if (n > 128) SETERRQ1(PETSC_ERR_SUP,"Can only set 256 columns at a time; trying to set %D",n);
1264 
1265   for (i=0; i<m; i++) {
1266     for (j=0; j<3-sdim; j++) dxm++;
1267     tmp = *dxm++ - starts[0];
1268     for (j=0; j<sdim-1; j++) {
1269       if ((*dxm++ - starts[j+1]) < 0 || tmp < 0) tmp = PETSC_MIN_INT;
1270       else                                      tmp = tmp*dims[j] + *(dxm-1) - starts[j+1];
1271     }
1272     dxm++;
1273     jdxm[i] = tmp;
1274   }
1275   for (i=0; i<n; i++) {
1276     for (j=0; j<3-sdim; j++) dxn++;
1277     tmp = *dxn++ - starts[0];
1278     for (j=0; j<sdim-1; j++) {
1279       if ((*dxn++ - starts[j+1]) < 0 || tmp < 0) tmp = PETSC_MIN_INT;
1280       else                                       tmp = tmp*dims[j] + *(dxn-1) - starts[j+1];
1281     }
1282     dxn++;
1283     jdxn[i] = tmp;
1284   }
1285   ierr = MatSetValuesBlockedLocal(mat,m,jdxm,n,jdxn,v,addv);CHKERRQ(ierr);
1286   PetscFunctionReturn(0);
1287 }
1288 
1289 #undef __FUNCT__
1290 #define __FUNCT__ "MatSetStencil"
1291 /*@
1292    MatSetStencil - Sets the grid information for setting values into a matrix via
1293         MatSetValuesStencil()
1294 
1295    Not Collective
1296 
1297    Input Parameters:
1298 +  mat - the matrix
1299 .  dim - dimension of the grid 1, 2, or 3
1300 .  dims - number of grid points in x, y, and z direction, including ghost points on your processor
1301 .  starts - starting point of ghost nodes on your processor in x, y, and z direction
1302 -  dof - number of degrees of freedom per node
1303 
1304 
1305    Inspired by the structured grid interface to the HYPRE package
1306    (www.llnl.gov/CASC/hyper)
1307 
1308    For matrices generated with DAGetMatrix() this routine is automatically called and so not needed by the
1309    user.
1310 
1311    Level: beginner
1312 
1313    Concepts: matrices^putting entries in
1314 
1315 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal()
1316           MatSetValues(), MatSetValuesBlockedStencil(), MatSetValuesStencil()
1317 @*/
1318 PetscErrorCode PETSCMAT_DLLEXPORT MatSetStencil(Mat mat,PetscInt dim,const PetscInt dims[],const PetscInt starts[],PetscInt dof)
1319 {
1320   PetscInt i;
1321 
1322   PetscFunctionBegin;
1323   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1324   PetscValidIntPointer(dims,3);
1325   PetscValidIntPointer(starts,4);
1326 
1327   mat->stencil.dim = dim + (dof > 1);
1328   for (i=0; i<dim; i++) {
1329     mat->stencil.dims[i]   = dims[dim-i-1];      /* copy the values in backwards */
1330     mat->stencil.starts[i] = starts[dim-i-1];
1331   }
1332   mat->stencil.dims[dim]   = dof;
1333   mat->stencil.starts[dim] = 0;
1334   mat->stencil.noc         = (PetscTruth)(dof == 1);
1335   PetscFunctionReturn(0);
1336 }
1337 
1338 #undef __FUNCT__
1339 #define __FUNCT__ "MatSetValuesBlocked"
1340 /*@
1341    MatSetValuesBlocked - Inserts or adds a block of values into a matrix.
1342 
1343    Not Collective
1344 
1345    Input Parameters:
1346 +  mat - the matrix
1347 .  v - a logically two-dimensional array of values
1348 .  m, idxm - the number of block rows and their global block indices
1349 .  n, idxn - the number of block columns and their global block indices
1350 -  addv - either ADD_VALUES or INSERT_VALUES, where
1351    ADD_VALUES adds values to any existing entries, and
1352    INSERT_VALUES replaces existing entries with new values
1353 
1354    Notes:
1355    The m and n count the NUMBER of blocks in the row direction and column direction,
1356    NOT the total number of rows/columns; for example, if the block size is 2 and
1357    you are passing in values for rows 2,3,4,5  then m would be 2 (not 4).
1358    The values in idxm would be 1 2; that is the first index for each block divided by
1359    the block size.
1360 
1361    Note that you must call MatSetBlockSize() when constructing this matrix (and before
1362    preallocating it).
1363 
1364    By default the values, v, are row-oriented and unsorted. So the layout of
1365    v is the same as for MatSetValues(). See MatSetOption() for other options.
1366 
1367    Calls to MatSetValuesBlocked() with the INSERT_VALUES and ADD_VALUES
1368    options cannot be mixed without intervening calls to the assembly
1369    routines.
1370 
1371    MatSetValuesBlocked() uses 0-based row and column numbers in Fortran
1372    as well as in C.
1373 
1374    Negative indices may be passed in idxm and idxn, these rows and columns are
1375    simply ignored. This allows easily inserting element stiffness matrices
1376    with homogeneous Dirchlet boundary conditions that you don't want represented
1377    in the matrix.
1378 
1379    Each time an entry is set within a sparse matrix via MatSetValues(),
1380    internal searching must be done to determine where to place the the
1381    data in the matrix storage space.  By instead inserting blocks of
1382    entries via MatSetValuesBlocked(), the overhead of matrix assembly is
1383    reduced.
1384 
1385    Example:
1386 $   Suppose m=n=2 and block size(bs) = 2 The array is
1387 $
1388 $   1  2  | 3  4
1389 $   5  6  | 7  8
1390 $   - - - | - - -
1391 $   9  10 | 11 12
1392 $   13 14 | 15 16
1393 $
1394 $   v[] should be passed in like
1395 $   v[] = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16]
1396 $
1397 $  If you are not using row oriented storage of v (that is you called MatSetOption(mat,MAT_ROW_ORIENTED,PETSC_FALSE)) then
1398 $   v[] = [1,5,9,13,2,6,10,14,3,7,11,15,4,8,12,16]
1399 
1400    Level: intermediate
1401 
1402    Concepts: matrices^putting entries in blocked
1403 
1404 .seealso: MatSetBlockSize(), MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValues(), MatSetValuesBlockedLocal()
1405 @*/
1406 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesBlocked(Mat mat,PetscInt m,const PetscInt idxm[],PetscInt n,const PetscInt idxn[],const PetscScalar v[],InsertMode addv)
1407 {
1408   PetscErrorCode ierr;
1409 
1410   PetscFunctionBegin;
1411   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1412   PetscValidType(mat,1);
1413   if (!m || !n) PetscFunctionReturn(0); /* no values to insert */
1414   PetscValidIntPointer(idxm,3);
1415   PetscValidIntPointer(idxn,5);
1416   PetscValidScalarPointer(v,6);
1417   ierr = MatPreallocated(mat);CHKERRQ(ierr);
1418   if (mat->insertmode == NOT_SET_VALUES) {
1419     mat->insertmode = addv;
1420   }
1421 #if defined(PETSC_USE_DEBUG)
1422   else if (mat->insertmode != addv) {
1423     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
1424   }
1425   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1426 #endif
1427 
1428   if (mat->assembled) {
1429     mat->was_assembled = PETSC_TRUE;
1430     mat->assembled     = PETSC_FALSE;
1431   }
1432   ierr = PetscLogEventBegin(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
1433   if (mat->ops->setvaluesblocked) {
1434     ierr = (*mat->ops->setvaluesblocked)(mat,m,idxm,n,idxn,v,addv);CHKERRQ(ierr);
1435   } else {
1436     PetscInt buf[4096],*ibufm=0,*ibufn=0;
1437     PetscInt i,j,*iidxm,*iidxn,bs=mat->rmap->bs;
1438     if ((m+n)*bs <= 4096) {
1439       iidxm = buf; iidxn = buf + m*bs;
1440     } else {
1441       ierr = PetscMalloc2(m*bs,PetscInt,&ibufm,n*bs,PetscInt,&ibufn);CHKERRQ(ierr);
1442       iidxm = ibufm; iidxn = ibufn;
1443     }
1444     for (i=0; i<m; i++) {
1445       for (j=0; j<bs; j++) {
1446 	iidxm[i*bs+j] = bs*idxm[i] + j;
1447       }
1448     }
1449     for (i=0; i<n; i++) {
1450       for (j=0; j<bs; j++) {
1451 	iidxn[i*bs+j] = bs*idxn[i] + j;
1452       }
1453     }
1454     ierr = MatSetValues(mat,bs*m,iidxm,bs*n,iidxn,v,addv);CHKERRQ(ierr);
1455     ierr = PetscFree2(ibufm,ibufn);CHKERRQ(ierr);
1456   }
1457   ierr = PetscLogEventEnd(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
1458   PetscFunctionReturn(0);
1459 }
1460 
1461 #undef __FUNCT__
1462 #define __FUNCT__ "MatGetValues"
1463 /*@
1464    MatGetValues - Gets a block of values from a matrix.
1465 
1466    Not Collective; currently only returns a local block
1467 
1468    Input Parameters:
1469 +  mat - the matrix
1470 .  v - a logically two-dimensional array for storing the values
1471 .  m, idxm - the number of rows and their global indices
1472 -  n, idxn - the number of columns and their global indices
1473 
1474    Notes:
1475    The user must allocate space (m*n PetscScalars) for the values, v.
1476    The values, v, are then returned in a row-oriented format,
1477    analogous to that used by default in MatSetValues().
1478 
1479    MatGetValues() uses 0-based row and column numbers in
1480    Fortran as well as in C.
1481 
1482    MatGetValues() requires that the matrix has been assembled
1483    with MatAssemblyBegin()/MatAssemblyEnd().  Thus, calls to
1484    MatSetValues() and MatGetValues() CANNOT be made in succession
1485    without intermediate matrix assembly.
1486 
1487    Negative row or column indices will be ignored and those locations in v[] will be
1488    left unchanged.
1489 
1490    Level: advanced
1491 
1492    Concepts: matrices^accessing values
1493 
1494 .seealso: MatGetRow(), MatGetSubMatrices(), MatSetValues()
1495 @*/
1496 PetscErrorCode PETSCMAT_DLLEXPORT MatGetValues(Mat mat,PetscInt m,const PetscInt idxm[],PetscInt n,const PetscInt idxn[],PetscScalar v[])
1497 {
1498   PetscErrorCode ierr;
1499 
1500   PetscFunctionBegin;
1501   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1502   PetscValidType(mat,1);
1503   PetscValidIntPointer(idxm,3);
1504   PetscValidIntPointer(idxn,5);
1505   PetscValidScalarPointer(v,6);
1506   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1507   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1508   if (!mat->ops->getvalues) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
1509   ierr = MatPreallocated(mat);CHKERRQ(ierr);
1510 
1511   ierr = PetscLogEventBegin(MAT_GetValues,mat,0,0,0);CHKERRQ(ierr);
1512   ierr = (*mat->ops->getvalues)(mat,m,idxm,n,idxn,v);CHKERRQ(ierr);
1513   ierr = PetscLogEventEnd(MAT_GetValues,mat,0,0,0);CHKERRQ(ierr);
1514   PetscFunctionReturn(0);
1515 }
1516 
1517 #undef __FUNCT__
1518 #define __FUNCT__ "MatSetLocalToGlobalMapping"
1519 /*@
1520    MatSetLocalToGlobalMapping - Sets a local-to-global numbering for use by
1521    the routine MatSetValuesLocal() to allow users to insert matrix entries
1522    using a local (per-processor) numbering.
1523 
1524    Not Collective
1525 
1526    Input Parameters:
1527 +  x - the matrix
1528 -  mapping - mapping created with ISLocalToGlobalMappingCreate()
1529              or ISLocalToGlobalMappingCreateIS()
1530 
1531    Level: intermediate
1532 
1533    Concepts: matrices^local to global mapping
1534    Concepts: local to global mapping^for matrices
1535 
1536 .seealso:  MatAssemblyBegin(), MatAssemblyEnd(), MatSetValues(), MatSetValuesLocal()
1537 @*/
1538 PetscErrorCode PETSCMAT_DLLEXPORT MatSetLocalToGlobalMapping(Mat x,ISLocalToGlobalMapping mapping)
1539 {
1540   PetscErrorCode ierr;
1541   PetscFunctionBegin;
1542   PetscValidHeaderSpecific(x,MAT_COOKIE,1);
1543   PetscValidType(x,1);
1544   PetscValidHeaderSpecific(mapping,IS_LTOGM_COOKIE,2);
1545   if (x->mapping) {
1546     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Mapping already set for matrix");
1547   }
1548   ierr = MatPreallocated(x);CHKERRQ(ierr);
1549 
1550   if (x->ops->setlocaltoglobalmapping) {
1551     ierr = (*x->ops->setlocaltoglobalmapping)(x,mapping);CHKERRQ(ierr);
1552   } else {
1553     ierr = PetscObjectReference((PetscObject)mapping);CHKERRQ(ierr);
1554     if (x->mapping) { ierr = ISLocalToGlobalMappingDestroy(x->mapping);CHKERRQ(ierr); }
1555     x->mapping = mapping;
1556   }
1557   PetscFunctionReturn(0);
1558 }
1559 
1560 #undef __FUNCT__
1561 #define __FUNCT__ "MatSetLocalToGlobalMappingBlock"
1562 /*@
1563    MatSetLocalToGlobalMappingBlock - Sets a local-to-global numbering for use
1564    by the routine MatSetValuesBlockedLocal() to allow users to insert matrix
1565    entries using a local (per-processor) numbering.
1566 
1567    Not Collective
1568 
1569    Input Parameters:
1570 +  x - the matrix
1571 -  mapping - mapping created with ISLocalToGlobalMappingCreate() or
1572              ISLocalToGlobalMappingCreateIS()
1573 
1574    Level: intermediate
1575 
1576    Concepts: matrices^local to global mapping blocked
1577    Concepts: local to global mapping^for matrices, blocked
1578 
1579 .seealso:  MatAssemblyBegin(), MatAssemblyEnd(), MatSetValues(), MatSetValuesBlockedLocal(),
1580            MatSetValuesBlocked(), MatSetValuesLocal()
1581 @*/
1582 PetscErrorCode PETSCMAT_DLLEXPORT MatSetLocalToGlobalMappingBlock(Mat x,ISLocalToGlobalMapping mapping)
1583 {
1584   PetscErrorCode ierr;
1585   PetscFunctionBegin;
1586   PetscValidHeaderSpecific(x,MAT_COOKIE,1);
1587   PetscValidType(x,1);
1588   PetscValidHeaderSpecific(mapping,IS_LTOGM_COOKIE,2);
1589   if (x->bmapping) {
1590     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Mapping already set for matrix");
1591   }
1592   ierr = PetscObjectReference((PetscObject)mapping);CHKERRQ(ierr);
1593   if (x->bmapping) { ierr = ISLocalToGlobalMappingDestroy(x->bmapping);CHKERRQ(ierr); }
1594   x->bmapping = mapping;
1595   PetscFunctionReturn(0);
1596 }
1597 
1598 #undef __FUNCT__
1599 #define __FUNCT__ "MatSetValuesLocal"
1600 /*@
1601    MatSetValuesLocal - Inserts or adds values into certain locations of a matrix,
1602    using a local ordering of the nodes.
1603 
1604    Not Collective
1605 
1606    Input Parameters:
1607 +  x - the matrix
1608 .  nrow, irow - number of rows and their local indices
1609 .  ncol, icol - number of columns and their local indices
1610 .  y -  a logically two-dimensional array of values
1611 -  addv - either INSERT_VALUES or ADD_VALUES, where
1612    ADD_VALUES adds values to any existing entries, and
1613    INSERT_VALUES replaces existing entries with new values
1614 
1615    Notes:
1616    Before calling MatSetValuesLocal(), the user must first set the
1617    local-to-global mapping by calling MatSetLocalToGlobalMapping().
1618 
1619    Calls to MatSetValuesLocal() with the INSERT_VALUES and ADD_VALUES
1620    options cannot be mixed without intervening calls to the assembly
1621    routines.
1622 
1623    These values may be cached, so MatAssemblyBegin() and MatAssemblyEnd()
1624    MUST be called after all calls to MatSetValuesLocal() have been completed.
1625 
1626    Level: intermediate
1627 
1628    Concepts: matrices^putting entries in with local numbering
1629 
1630 .seealso:  MatAssemblyBegin(), MatAssemblyEnd(), MatSetValues(), MatSetLocalToGlobalMapping(),
1631            MatSetValueLocal()
1632 @*/
1633 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesLocal(Mat mat,PetscInt nrow,const PetscInt irow[],PetscInt ncol,const PetscInt icol[],const PetscScalar y[],InsertMode addv)
1634 {
1635   PetscErrorCode ierr;
1636   PetscInt       irowm[2048],icolm[2048];
1637 
1638   PetscFunctionBegin;
1639   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1640   PetscValidType(mat,1);
1641   if (!nrow || !ncol) PetscFunctionReturn(0); /* no values to insert */
1642   PetscValidIntPointer(irow,3);
1643   PetscValidIntPointer(icol,5);
1644   PetscValidScalarPointer(y,6);
1645   ierr = MatPreallocated(mat);CHKERRQ(ierr);
1646   if (mat->insertmode == NOT_SET_VALUES) {
1647     mat->insertmode = addv;
1648   }
1649 #if defined(PETSC_USE_DEBUG)
1650   else if (mat->insertmode != addv) {
1651     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
1652   }
1653   if (!mat->ops->setvalueslocal && (nrow > 2048 || ncol > 2048)) {
1654     SETERRQ2(PETSC_ERR_SUP,"Number column/row indices must be <= 2048: are %D %D",nrow,ncol);
1655   }
1656   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1657 #endif
1658 
1659   if (mat->assembled) {
1660     mat->was_assembled = PETSC_TRUE;
1661     mat->assembled     = PETSC_FALSE;
1662   }
1663   ierr = PetscLogEventBegin(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
1664   if (!mat->ops->setvalueslocal) {
1665     ierr = ISLocalToGlobalMappingApply(mat->mapping,nrow,irow,irowm);CHKERRQ(ierr);
1666     ierr = ISLocalToGlobalMappingApply(mat->mapping,ncol,icol,icolm);CHKERRQ(ierr);
1667     ierr = (*mat->ops->setvalues)(mat,nrow,irowm,ncol,icolm,y,addv);CHKERRQ(ierr);
1668   } else {
1669     ierr = (*mat->ops->setvalueslocal)(mat,nrow,irow,ncol,icol,y,addv);CHKERRQ(ierr);
1670   }
1671   mat->same_nonzero = PETSC_FALSE;
1672   ierr = PetscLogEventEnd(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
1673   PetscFunctionReturn(0);
1674 }
1675 
1676 #undef __FUNCT__
1677 #define __FUNCT__ "MatSetValuesBlockedLocal"
1678 /*@
1679    MatSetValuesBlockedLocal - Inserts or adds values into certain locations of a matrix,
1680    using a local ordering of the nodes a block at a time.
1681 
1682    Not Collective
1683 
1684    Input Parameters:
1685 +  x - the matrix
1686 .  nrow, irow - number of rows and their local indices
1687 .  ncol, icol - number of columns and their local indices
1688 .  y -  a logically two-dimensional array of values
1689 -  addv - either INSERT_VALUES or ADD_VALUES, where
1690    ADD_VALUES adds values to any existing entries, and
1691    INSERT_VALUES replaces existing entries with new values
1692 
1693    Notes:
1694    Before calling MatSetValuesBlockedLocal(), the user must first set the
1695    block size using MatSetBlockSize(), and the local-to-global mapping by
1696    calling MatSetLocalToGlobalMappingBlock(), where the mapping MUST be
1697    set for matrix blocks, not for matrix elements.
1698 
1699    Calls to MatSetValuesBlockedLocal() with the INSERT_VALUES and ADD_VALUES
1700    options cannot be mixed without intervening calls to the assembly
1701    routines.
1702 
1703    These values may be cached, so MatAssemblyBegin() and MatAssemblyEnd()
1704    MUST be called after all calls to MatSetValuesBlockedLocal() have been completed.
1705 
1706    Level: intermediate
1707 
1708    Concepts: matrices^putting blocked values in with local numbering
1709 
1710 .seealso:  MatSetBlockSize(), MatSetLocalToGlobalMappingBlock(), MatAssemblyBegin(), MatAssemblyEnd(),
1711            MatSetValuesLocal(), MatSetLocalToGlobalMappingBlock(), MatSetValuesBlocked()
1712 @*/
1713 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesBlockedLocal(Mat mat,PetscInt nrow,const PetscInt irow[],PetscInt ncol,const PetscInt icol[],const PetscScalar y[],InsertMode addv)
1714 {
1715   PetscErrorCode ierr;
1716   PetscInt       irowm[2048],icolm[2048];
1717 
1718   PetscFunctionBegin;
1719   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1720   PetscValidType(mat,1);
1721   if (!nrow || !ncol) PetscFunctionReturn(0); /* no values to insert */
1722   PetscValidIntPointer(irow,3);
1723   PetscValidIntPointer(icol,5);
1724   PetscValidScalarPointer(y,6);
1725   ierr = MatPreallocated(mat);CHKERRQ(ierr);
1726   if (mat->insertmode == NOT_SET_VALUES) {
1727     mat->insertmode = addv;
1728   }
1729 #if defined(PETSC_USE_DEBUG)
1730   else if (mat->insertmode != addv) {
1731     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
1732   }
1733   if (!mat->bmapping) {
1734     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Local to global never set with MatSetLocalToGlobalMappingBlock()");
1735   }
1736   if (nrow > 2048 || ncol > 2048) {
1737     SETERRQ2(PETSC_ERR_SUP,"Number column/row indices must be <= 2048: are %D %D",nrow,ncol);
1738   }
1739   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1740 #endif
1741 
1742   if (mat->assembled) {
1743     mat->was_assembled = PETSC_TRUE;
1744     mat->assembled     = PETSC_FALSE;
1745   }
1746   ierr = PetscLogEventBegin(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
1747   ierr = ISLocalToGlobalMappingApply(mat->bmapping,nrow,irow,irowm);CHKERRQ(ierr);
1748   ierr = ISLocalToGlobalMappingApply(mat->bmapping,ncol,icol,icolm);CHKERRQ(ierr);
1749   if (mat->ops->setvaluesblocked) {
1750   ierr = (*mat->ops->setvaluesblocked)(mat,nrow,irowm,ncol,icolm,y,addv);CHKERRQ(ierr);
1751   } else {
1752     PetscInt buf[4096],*ibufm=0,*ibufn=0;
1753     PetscInt i,j,*iirowm,*iicolm,bs=mat->rmap->bs;
1754     if ((nrow+ncol)*bs <= 4096) {
1755       iirowm = buf; iicolm = buf + nrow*bs;
1756     } else {
1757       ierr = PetscMalloc2(nrow*bs,PetscInt,&ibufm,ncol*bs,PetscInt,&ibufn);CHKERRQ(ierr);
1758       iirowm = ibufm; iicolm = ibufn;
1759     }
1760     for (i=0; i<nrow; i++) {
1761       for (j=0; j<bs; j++) {
1762 	iirowm[i*bs+j] = bs*irowm[i] + j;
1763       }
1764     }
1765     for (i=0; i<ncol; i++) {
1766       for (j=0; j<bs; j++) {
1767 	iicolm[i*bs+j] = bs*icolm[i] + j;
1768       }
1769     }
1770     ierr = MatSetValues(mat,bs*nrow,iirowm,bs*ncol,iicolm,y,addv);CHKERRQ(ierr);
1771     ierr = PetscFree2(ibufm,ibufn);CHKERRQ(ierr);
1772   }
1773   ierr = PetscLogEventEnd(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
1774   PetscFunctionReturn(0);
1775 }
1776 
1777 #undef __FUNCT__
1778 #define __FUNCT__ "MatMultDiagonalBlock"
1779 /*@
1780    MatMultDiagonalBlock - Computes the matrix-vector product, y = Dx. Where D is defined by the inode or block structure of the diagonal
1781 
1782    Collective on Mat and Vec
1783 
1784    Input Parameters:
1785 +  mat - the matrix
1786 -  x   - the vector to be multiplied
1787 
1788    Output Parameters:
1789 .  y - the result
1790 
1791    Notes:
1792    The vectors x and y cannot be the same.  I.e., one cannot
1793    call MatMult(A,y,y).
1794 
1795    Level: developer
1796 
1797    Concepts: matrix-vector product
1798 
1799 .seealso: MatMultTranspose(), MatMultAdd(), MatMultTransposeAdd()
1800 @*/
1801 PetscErrorCode PETSCMAT_DLLEXPORT MatMultDiagonalBlock(Mat mat,Vec x,Vec y)
1802 {
1803   PetscErrorCode ierr;
1804 
1805   PetscFunctionBegin;
1806   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1807   PetscValidType(mat,1);
1808   PetscValidHeaderSpecific(x,VEC_COOKIE,2);
1809   PetscValidHeaderSpecific(y,VEC_COOKIE,3);
1810 
1811   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1812   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1813   if (x == y) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"x and y must be different vectors");
1814   ierr = MatPreallocated(mat);CHKERRQ(ierr);
1815 
1816   if (!mat->ops->multdiagonalblock) SETERRQ(PETSC_ERR_SUP,"This matrix type does not have a multiply defined");
1817   ierr = (*mat->ops->multdiagonalblock)(mat,x,y);CHKERRQ(ierr);
1818   ierr = PetscObjectStateIncrease((PetscObject)y);CHKERRQ(ierr);
1819   PetscFunctionReturn(0);
1820 }
1821 
1822 /* --------------------------------------------------------*/
1823 #undef __FUNCT__
1824 #define __FUNCT__ "MatMult"
1825 /*@
1826    MatMult - Computes the matrix-vector product, y = Ax.
1827 
1828    Collective on Mat and Vec
1829 
1830    Input Parameters:
1831 +  mat - the matrix
1832 -  x   - the vector to be multiplied
1833 
1834    Output Parameters:
1835 .  y - the result
1836 
1837    Notes:
1838    The vectors x and y cannot be the same.  I.e., one cannot
1839    call MatMult(A,y,y).
1840 
1841    Level: beginner
1842 
1843    Concepts: matrix-vector product
1844 
1845 .seealso: MatMultTranspose(), MatMultAdd(), MatMultTransposeAdd()
1846 @*/
1847 PetscErrorCode PETSCMAT_DLLEXPORT MatMult(Mat mat,Vec x,Vec y)
1848 {
1849   PetscErrorCode ierr;
1850 
1851   PetscFunctionBegin;
1852   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1853   PetscValidType(mat,1);
1854   PetscValidHeaderSpecific(x,VEC_COOKIE,2);
1855   PetscValidHeaderSpecific(y,VEC_COOKIE,3);
1856 
1857   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1858   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1859   if (x == y) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"x and y must be different vectors");
1860 #ifndef PETSC_HAVE_CONSTRAINTS
1861   if (mat->cmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
1862   if (mat->rmap->N != y->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec y: global dim %D %D",mat->rmap->N,y->map->N);
1863   if (mat->rmap->n != y->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec y: local dim %D %D",mat->rmap->n,y->map->n);
1864 #endif
1865   ierr = MatPreallocated(mat);CHKERRQ(ierr);
1866 
1867   if (mat->nullsp) {
1868     ierr = MatNullSpaceRemove(mat->nullsp,x,&x);CHKERRQ(ierr);
1869   }
1870 
1871   if (!mat->ops->mult) SETERRQ(PETSC_ERR_SUP,"This matrix type does not have a multiply defined");
1872   ierr = PetscLogEventBegin(MAT_Mult,mat,x,y,0);CHKERRQ(ierr);
1873   ierr = (*mat->ops->mult)(mat,x,y);CHKERRQ(ierr);
1874   ierr = PetscLogEventEnd(MAT_Mult,mat,x,y,0);CHKERRQ(ierr);
1875 
1876   if (mat->nullsp) {
1877     ierr = MatNullSpaceRemove(mat->nullsp,y,PETSC_NULL);CHKERRQ(ierr);
1878   }
1879   ierr = PetscObjectStateIncrease((PetscObject)y);CHKERRQ(ierr);
1880   PetscFunctionReturn(0);
1881 }
1882 
1883 #undef __FUNCT__
1884 #define __FUNCT__ "MatMultTranspose"
1885 /*@
1886    MatMultTranspose - Computes matrix transpose times a vector.
1887 
1888    Collective on Mat and Vec
1889 
1890    Input Parameters:
1891 +  mat - the matrix
1892 -  x   - the vector to be multilplied
1893 
1894    Output Parameters:
1895 .  y - the result
1896 
1897    Notes:
1898    The vectors x and y cannot be the same.  I.e., one cannot
1899    call MatMultTranspose(A,y,y).
1900 
1901    Level: beginner
1902 
1903    Concepts: matrix vector product^transpose
1904 
1905 .seealso: MatMult(), MatMultAdd(), MatMultTransposeAdd()
1906 @*/
1907 PetscErrorCode PETSCMAT_DLLEXPORT MatMultTranspose(Mat mat,Vec x,Vec y)
1908 {
1909   PetscErrorCode ierr;
1910 
1911   PetscFunctionBegin;
1912   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1913   PetscValidType(mat,1);
1914   PetscValidHeaderSpecific(x,VEC_COOKIE,2);
1915   PetscValidHeaderSpecific(y,VEC_COOKIE,3);
1916 
1917   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1918   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1919   if (x == y) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"x and y must be different vectors");
1920 #ifndef PETSC_HAVE_CONSTRAINTS
1921   if (mat->rmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->rmap->N,x->map->N);
1922   if (mat->cmap->N != y->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec y: global dim %D %D",mat->cmap->N,y->map->N);
1923 #endif
1924   ierr = MatPreallocated(mat);CHKERRQ(ierr);
1925 
1926   if (!mat->ops->multtranspose) SETERRQ(PETSC_ERR_SUP,"This matrix type does not have a multiply tranpose defined");
1927   ierr = PetscLogEventBegin(MAT_MultTranspose,mat,x,y,0);CHKERRQ(ierr);
1928   ierr = (*mat->ops->multtranspose)(mat,x,y);CHKERRQ(ierr);
1929   ierr = PetscLogEventEnd(MAT_MultTranspose,mat,x,y,0);CHKERRQ(ierr);
1930   ierr = PetscObjectStateIncrease((PetscObject)y);CHKERRQ(ierr);
1931   PetscFunctionReturn(0);
1932 }
1933 
1934 #undef __FUNCT__
1935 #define __FUNCT__ "MatMultAdd"
1936 /*@
1937     MatMultAdd -  Computes v3 = v2 + A * v1.
1938 
1939     Collective on Mat and Vec
1940 
1941     Input Parameters:
1942 +   mat - the matrix
1943 -   v1, v2 - the vectors
1944 
1945     Output Parameters:
1946 .   v3 - the result
1947 
1948     Notes:
1949     The vectors v1 and v3 cannot be the same.  I.e., one cannot
1950     call MatMultAdd(A,v1,v2,v1).
1951 
1952     Level: beginner
1953 
1954     Concepts: matrix vector product^addition
1955 
1956 .seealso: MatMultTranspose(), MatMult(), MatMultTransposeAdd()
1957 @*/
1958 PetscErrorCode PETSCMAT_DLLEXPORT MatMultAdd(Mat mat,Vec v1,Vec v2,Vec v3)
1959 {
1960   PetscErrorCode ierr;
1961 
1962   PetscFunctionBegin;
1963   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1964   PetscValidType(mat,1);
1965   PetscValidHeaderSpecific(v1,VEC_COOKIE,2);
1966   PetscValidHeaderSpecific(v2,VEC_COOKIE,3);
1967   PetscValidHeaderSpecific(v3,VEC_COOKIE,4);
1968 
1969   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1970   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1971   if (mat->cmap->N != v1->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec v1: global dim %D %D",mat->cmap->N,v1->map->N);
1972   /* if (mat->rmap->N != v2->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec v2: global dim %D %D",mat->rmap->N,v2->map->N);
1973      if (mat->rmap->N != v3->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec v3: global dim %D %D",mat->rmap->N,v3->map->N); */
1974   if (mat->rmap->n != v3->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec v3: local dim %D %D",mat->rmap->n,v3->map->n);
1975   if (mat->rmap->n != v2->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec v2: local dim %D %D",mat->rmap->n,v2->map->n);
1976   if (v1 == v3) SETERRQ(PETSC_ERR_ARG_IDN,"v1 and v3 must be different vectors");
1977   ierr = MatPreallocated(mat);CHKERRQ(ierr);
1978 
1979   ierr = PetscLogEventBegin(MAT_MultAdd,mat,v1,v2,v3);CHKERRQ(ierr);
1980   ierr = (*mat->ops->multadd)(mat,v1,v2,v3);CHKERRQ(ierr);
1981   ierr = PetscLogEventEnd(MAT_MultAdd,mat,v1,v2,v3);CHKERRQ(ierr);
1982   ierr = PetscObjectStateIncrease((PetscObject)v3);CHKERRQ(ierr);
1983   PetscFunctionReturn(0);
1984 }
1985 
1986 #undef __FUNCT__
1987 #define __FUNCT__ "MatMultTransposeAdd"
1988 /*@
1989    MatMultTransposeAdd - Computes v3 = v2 + A' * v1.
1990 
1991    Collective on Mat and Vec
1992 
1993    Input Parameters:
1994 +  mat - the matrix
1995 -  v1, v2 - the vectors
1996 
1997    Output Parameters:
1998 .  v3 - the result
1999 
2000    Notes:
2001    The vectors v1 and v3 cannot be the same.  I.e., one cannot
2002    call MatMultTransposeAdd(A,v1,v2,v1).
2003 
2004    Level: beginner
2005 
2006    Concepts: matrix vector product^transpose and addition
2007 
2008 .seealso: MatMultTranspose(), MatMultAdd(), MatMult()
2009 @*/
2010 PetscErrorCode PETSCMAT_DLLEXPORT MatMultTransposeAdd(Mat mat,Vec v1,Vec v2,Vec v3)
2011 {
2012   PetscErrorCode ierr;
2013 
2014   PetscFunctionBegin;
2015   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2016   PetscValidType(mat,1);
2017   PetscValidHeaderSpecific(v1,VEC_COOKIE,2);
2018   PetscValidHeaderSpecific(v2,VEC_COOKIE,3);
2019   PetscValidHeaderSpecific(v3,VEC_COOKIE,4);
2020 
2021   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2022   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2023   if (!mat->ops->multtransposeadd) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2024   if (v1 == v3) SETERRQ(PETSC_ERR_ARG_IDN,"v1 and v3 must be different vectors");
2025   if (mat->rmap->N != v1->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec v1: global dim %D %D",mat->rmap->N,v1->map->N);
2026   if (mat->cmap->N != v2->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec v2: global dim %D %D",mat->cmap->N,v2->map->N);
2027   if (mat->cmap->N != v3->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec v3: global dim %D %D",mat->cmap->N,v3->map->N);
2028   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2029 
2030   ierr = PetscLogEventBegin(MAT_MultTransposeAdd,mat,v1,v2,v3);CHKERRQ(ierr);
2031   ierr = (*mat->ops->multtransposeadd)(mat,v1,v2,v3);CHKERRQ(ierr);
2032   ierr = PetscLogEventEnd(MAT_MultTransposeAdd,mat,v1,v2,v3);CHKERRQ(ierr);
2033   ierr = PetscObjectStateIncrease((PetscObject)v3);CHKERRQ(ierr);
2034   PetscFunctionReturn(0);
2035 }
2036 
2037 #undef __FUNCT__
2038 #define __FUNCT__ "MatMultConstrained"
2039 /*@
2040    MatMultConstrained - The inner multiplication routine for a
2041    constrained matrix P^T A P.
2042 
2043    Collective on Mat and Vec
2044 
2045    Input Parameters:
2046 +  mat - the matrix
2047 -  x   - the vector to be multilplied
2048 
2049    Output Parameters:
2050 .  y - the result
2051 
2052    Notes:
2053    The vectors x and y cannot be the same.  I.e., one cannot
2054    call MatMult(A,y,y).
2055 
2056    Level: beginner
2057 
2058 .keywords: matrix, multiply, matrix-vector product, constraint
2059 .seealso: MatMult(), MatMultTranspose(), MatMultAdd(), MatMultTransposeAdd()
2060 @*/
2061 PetscErrorCode PETSCMAT_DLLEXPORT MatMultConstrained(Mat mat,Vec x,Vec y)
2062 {
2063   PetscErrorCode ierr;
2064 
2065   PetscFunctionBegin;
2066   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2067   PetscValidHeaderSpecific(x,VEC_COOKIE,2);
2068   PetscValidHeaderSpecific(y,VEC_COOKIE,3);
2069   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2070   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2071   if (x == y) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"x and y must be different vectors");
2072   if (mat->cmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
2073   if (mat->rmap->N != y->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec y: global dim %D %D",mat->rmap->N,y->map->N);
2074   if (mat->rmap->n != y->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec y: local dim %D %D",mat->rmap->n,y->map->n);
2075 
2076   ierr = PetscLogEventBegin(MAT_MultConstrained,mat,x,y,0);CHKERRQ(ierr);
2077   ierr = (*mat->ops->multconstrained)(mat,x,y);CHKERRQ(ierr);
2078   ierr = PetscLogEventEnd(MAT_MultConstrained,mat,x,y,0);CHKERRQ(ierr);
2079   ierr = PetscObjectStateIncrease((PetscObject)y);CHKERRQ(ierr);
2080 
2081   PetscFunctionReturn(0);
2082 }
2083 
2084 #undef __FUNCT__
2085 #define __FUNCT__ "MatMultTransposeConstrained"
2086 /*@
2087    MatMultTransposeConstrained - The inner multiplication routine for a
2088    constrained matrix P^T A^T P.
2089 
2090    Collective on Mat and Vec
2091 
2092    Input Parameters:
2093 +  mat - the matrix
2094 -  x   - the vector to be multilplied
2095 
2096    Output Parameters:
2097 .  y - the result
2098 
2099    Notes:
2100    The vectors x and y cannot be the same.  I.e., one cannot
2101    call MatMult(A,y,y).
2102 
2103    Level: beginner
2104 
2105 .keywords: matrix, multiply, matrix-vector product, constraint
2106 .seealso: MatMult(), MatMultTranspose(), MatMultAdd(), MatMultTransposeAdd()
2107 @*/
2108 PetscErrorCode PETSCMAT_DLLEXPORT MatMultTransposeConstrained(Mat mat,Vec x,Vec y)
2109 {
2110   PetscErrorCode ierr;
2111 
2112   PetscFunctionBegin;
2113   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2114   PetscValidHeaderSpecific(x,VEC_COOKIE,2);
2115   PetscValidHeaderSpecific(y,VEC_COOKIE,3);
2116   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2117   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2118   if (x == y) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"x and y must be different vectors");
2119   if (mat->rmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
2120   if (mat->cmap->N != y->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec y: global dim %D %D",mat->rmap->N,y->map->N);
2121 
2122   ierr = PetscLogEventBegin(MAT_MultConstrained,mat,x,y,0);CHKERRQ(ierr);
2123   ierr = (*mat->ops->multtransposeconstrained)(mat,x,y);CHKERRQ(ierr);
2124   ierr = PetscLogEventEnd(MAT_MultConstrained,mat,x,y,0);CHKERRQ(ierr);
2125   ierr = PetscObjectStateIncrease((PetscObject)y);CHKERRQ(ierr);
2126 
2127   PetscFunctionReturn(0);
2128 }
2129 /* ------------------------------------------------------------*/
2130 #undef __FUNCT__
2131 #define __FUNCT__ "MatGetInfo"
2132 /*@C
2133    MatGetInfo - Returns information about matrix storage (number of
2134    nonzeros, memory, etc.).
2135 
2136    Collective on Mat if MAT_GLOBAL_MAX or MAT_GLOBAL_SUM is used
2137    as the flag
2138 
2139    Input Parameters:
2140 .  mat - the matrix
2141 
2142    Output Parameters:
2143 +  flag - flag indicating the type of parameters to be returned
2144    (MAT_LOCAL - local matrix, MAT_GLOBAL_MAX - maximum over all processors,
2145    MAT_GLOBAL_SUM - sum over all processors)
2146 -  info - matrix information context
2147 
2148    Notes:
2149    The MatInfo context contains a variety of matrix data, including
2150    number of nonzeros allocated and used, number of mallocs during
2151    matrix assembly, etc.  Additional information for factored matrices
2152    is provided (such as the fill ratio, number of mallocs during
2153    factorization, etc.).  Much of this info is printed to PETSC_STDOUT
2154    when using the runtime options
2155 $       -info -mat_view_info
2156 
2157    Example for C/C++ Users:
2158    See the file ${PETSC_DIR}/include/petscmat.h for a complete list of
2159    data within the MatInfo context.  For example,
2160 .vb
2161       MatInfo info;
2162       Mat     A;
2163       double  mal, nz_a, nz_u;
2164 
2165       MatGetInfo(A,MAT_LOCAL,&info);
2166       mal  = info.mallocs;
2167       nz_a = info.nz_allocated;
2168 .ve
2169 
2170    Example for Fortran Users:
2171    Fortran users should declare info as a double precision
2172    array of dimension MAT_INFO_SIZE, and then extract the parameters
2173    of interest.  See the file ${PETSC_DIR}/include/finclude/petscmat.h
2174    a complete list of parameter names.
2175 .vb
2176       double  precision info(MAT_INFO_SIZE)
2177       double  precision mal, nz_a
2178       Mat     A
2179       integer ierr
2180 
2181       call MatGetInfo(A,MAT_LOCAL,info,ierr)
2182       mal = info(MAT_INFO_MALLOCS)
2183       nz_a = info(MAT_INFO_NZ_ALLOCATED)
2184 .ve
2185 
2186     Level: intermediate
2187 
2188     Concepts: matrices^getting information on
2189 
2190     Developer Note: fortran interface is not autogenerated as the f90
2191     interface defintion cannot be generated correctly [due to MatInfo]
2192 
2193 @*/
2194 PetscErrorCode PETSCMAT_DLLEXPORT MatGetInfo(Mat mat,MatInfoType flag,MatInfo *info)
2195 {
2196   PetscErrorCode ierr;
2197 
2198   PetscFunctionBegin;
2199   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2200   PetscValidType(mat,1);
2201   PetscValidPointer(info,3);
2202   if (!mat->ops->getinfo) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2203   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2204   ierr = (*mat->ops->getinfo)(mat,flag,info);CHKERRQ(ierr);
2205   PetscFunctionReturn(0);
2206 }
2207 
2208 /* ----------------------------------------------------------*/
2209 #undef __FUNCT__
2210 #define __FUNCT__ "MatILUDTFactor"
2211 /*@C
2212    MatILUDTFactor - Performs a drop tolerance ILU factorization.
2213 
2214    Collective on Mat
2215 
2216    Input Parameters:
2217 +  mat - the matrix
2218 .  row - row permutation
2219 .  col - column permutation
2220 -  info - information about the factorization to be done
2221 
2222    Output Parameters:
2223 .  fact - the factored matrix
2224 
2225    Level: developer
2226 
2227    Notes:
2228    Most users should employ the simplified KSP interface for linear solvers
2229    instead of working directly with matrix algebra routines such as this.
2230    See, e.g., KSPCreate().
2231 
2232     Concepts: matrices^ILUDT factorization
2233 
2234 .seealso: MatLUFactorSymbolic(), MatLUFactorNumeric(), MatCholeskyFactor(), MatFactorInfo
2235 @*/
2236 PetscErrorCode PETSCMAT_DLLEXPORT MatILUDTFactor(Mat mat,IS row,IS col,const MatFactorInfo *info,Mat *fact)
2237 {
2238   PetscErrorCode ierr;
2239 
2240   PetscFunctionBegin;
2241   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2242   PetscValidType(mat,1);
2243   if (row) PetscValidHeaderSpecific(row,IS_COOKIE,2);
2244   if (col) PetscValidHeaderSpecific(col,IS_COOKIE,3);
2245   PetscValidPointer(info,4);
2246   PetscValidPointer(fact,5);
2247   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2248   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2249   if (!mat->ops->iludtfactor) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2250   if (mat->rmap->N != mat->cmap->N) SETERRQ(PETSC_ERR_ARG_WRONG,"matrix must be square");
2251   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2252   ierr = PetscLogEventBegin(MAT_ILUFactor,mat,row,col,0);CHKERRQ(ierr);
2253   ierr = (*mat->ops->iludtfactor)(mat,row,col,info,fact);CHKERRQ(ierr);
2254   ierr = PetscLogEventEnd(MAT_ILUFactor,mat,row,col,0);CHKERRQ(ierr);
2255   ierr = PetscObjectStateIncrease((PetscObject)*fact);CHKERRQ(ierr);
2256 
2257   PetscFunctionReturn(0);
2258 }
2259 
2260 #undef __FUNCT__
2261 #define __FUNCT__ "MatLUFactor"
2262 /*@C
2263    MatLUFactor - Performs in-place LU factorization of matrix.
2264 
2265    Collective on Mat
2266 
2267    Input Parameters:
2268 +  mat - the matrix
2269 .  row - row permutation
2270 .  col - column permutation
2271 -  info - options for factorization, includes
2272 $          fill - expected fill as ratio of original fill.
2273 $          dtcol - pivot tolerance (0 no pivot, 1 full column pivoting)
2274 $                   Run with the option -info to determine an optimal value to use
2275 
2276    Notes:
2277    Most users should employ the simplified KSP interface for linear solvers
2278    instead of working directly with matrix algebra routines such as this.
2279    See, e.g., KSPCreate().
2280 
2281    This changes the state of the matrix to a factored matrix; it cannot be used
2282    for example with MatSetValues() unless one first calls MatSetUnfactored().
2283 
2284    Level: developer
2285 
2286    Concepts: matrices^LU factorization
2287 
2288 .seealso: MatLUFactorSymbolic(), MatLUFactorNumeric(), MatCholeskyFactor(),
2289           MatGetOrdering(), MatSetUnfactored(), MatFactorInfo
2290 
2291     Developer Note: fortran interface is not autogenerated as the f90
2292     interface defintion cannot be generated correctly [due to MatFactorInfo]
2293 
2294 @*/
2295 PetscErrorCode PETSCMAT_DLLEXPORT MatLUFactor(Mat mat,IS row,IS col,const MatFactorInfo *info)
2296 {
2297   PetscErrorCode ierr;
2298 
2299   PetscFunctionBegin;
2300   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2301   if (row) PetscValidHeaderSpecific(row,IS_COOKIE,2);
2302   if (col) PetscValidHeaderSpecific(col,IS_COOKIE,3);
2303   PetscValidPointer(info,4);
2304   PetscValidType(mat,1);
2305   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2306   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2307   if (!mat->ops->lufactor) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2308   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2309 
2310   ierr = PetscLogEventBegin(MAT_LUFactor,mat,row,col,0);CHKERRQ(ierr);
2311   ierr = (*mat->ops->lufactor)(mat,row,col,info);CHKERRQ(ierr);
2312   ierr = PetscLogEventEnd(MAT_LUFactor,mat,row,col,0);CHKERRQ(ierr);
2313   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
2314   PetscFunctionReturn(0);
2315 }
2316 
2317 #undef __FUNCT__
2318 #define __FUNCT__ "MatILUFactor"
2319 /*@C
2320    MatILUFactor - Performs in-place ILU factorization of matrix.
2321 
2322    Collective on Mat
2323 
2324    Input Parameters:
2325 +  mat - the matrix
2326 .  row - row permutation
2327 .  col - column permutation
2328 -  info - structure containing
2329 $      levels - number of levels of fill.
2330 $      expected fill - as ratio of original fill.
2331 $      1 or 0 - indicating force fill on diagonal (improves robustness for matrices
2332                 missing diagonal entries)
2333 
2334    Notes:
2335    Probably really in-place only when level of fill is zero, otherwise allocates
2336    new space to store factored matrix and deletes previous memory.
2337 
2338    Most users should employ the simplified KSP interface for linear solvers
2339    instead of working directly with matrix algebra routines such as this.
2340    See, e.g., KSPCreate().
2341 
2342    Level: developer
2343 
2344    Concepts: matrices^ILU factorization
2345 
2346 .seealso: MatILUFactorSymbolic(), MatLUFactorNumeric(), MatCholeskyFactor(), MatFactorInfo
2347 
2348     Developer Note: fortran interface is not autogenerated as the f90
2349     interface defintion cannot be generated correctly [due to MatFactorInfo]
2350 
2351 @*/
2352 PetscErrorCode PETSCMAT_DLLEXPORT MatILUFactor(Mat mat,IS row,IS col,const MatFactorInfo *info)
2353 {
2354   PetscErrorCode ierr;
2355 
2356   PetscFunctionBegin;
2357   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2358   if (row) PetscValidHeaderSpecific(row,IS_COOKIE,2);
2359   if (col) PetscValidHeaderSpecific(col,IS_COOKIE,3);
2360   PetscValidPointer(info,4);
2361   PetscValidType(mat,1);
2362   if (mat->rmap->N != mat->cmap->N) SETERRQ(PETSC_ERR_ARG_WRONG,"matrix must be square");
2363   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2364   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2365   if (!mat->ops->ilufactor) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2366   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2367 
2368   ierr = PetscLogEventBegin(MAT_ILUFactor,mat,row,col,0);CHKERRQ(ierr);
2369   ierr = (*mat->ops->ilufactor)(mat,row,col,info);CHKERRQ(ierr);
2370   ierr = PetscLogEventEnd(MAT_ILUFactor,mat,row,col,0);CHKERRQ(ierr);
2371   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
2372   PetscFunctionReturn(0);
2373 }
2374 
2375 #undef __FUNCT__
2376 #define __FUNCT__ "MatLUFactorSymbolic"
2377 /*@C
2378    MatLUFactorSymbolic - Performs symbolic LU factorization of matrix.
2379    Call this routine before calling MatLUFactorNumeric().
2380 
2381    Collective on Mat
2382 
2383    Input Parameters:
2384 +  fact - the factor matrix obtained with MatGetFactor()
2385 .  mat - the matrix
2386 .  row, col - row and column permutations
2387 -  info - options for factorization, includes
2388 $          fill - expected fill as ratio of original fill.
2389 $          dtcol - pivot tolerance (0 no pivot, 1 full column pivoting)
2390 $                   Run with the option -info to determine an optimal value to use
2391 
2392 
2393    Notes:
2394    See the users manual for additional information about
2395    choosing the fill factor for better efficiency.
2396 
2397    Most users should employ the simplified KSP interface for linear solvers
2398    instead of working directly with matrix algebra routines such as this.
2399    See, e.g., KSPCreate().
2400 
2401    Level: developer
2402 
2403    Concepts: matrices^LU symbolic factorization
2404 
2405 .seealso: MatLUFactor(), MatLUFactorNumeric(), MatCholeskyFactor(), MatFactorInfo
2406 
2407     Developer Note: fortran interface is not autogenerated as the f90
2408     interface defintion cannot be generated correctly [due to MatFactorInfo]
2409 
2410 @*/
2411 PetscErrorCode PETSCMAT_DLLEXPORT MatLUFactorSymbolic(Mat fact,Mat mat,IS row,IS col,const MatFactorInfo *info)
2412 {
2413   PetscErrorCode ierr;
2414 
2415   PetscFunctionBegin;
2416   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2417   if (row) PetscValidHeaderSpecific(row,IS_COOKIE,2);
2418   if (col) PetscValidHeaderSpecific(col,IS_COOKIE,3);
2419   PetscValidPointer(info,4);
2420   PetscValidType(mat,1);
2421   PetscValidPointer(fact,5);
2422   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2423   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2424   if (!(fact)->ops->lufactorsymbolic) SETERRQ1(PETSC_ERR_SUP,"Matrix type %s  symbolic LU",((PetscObject)mat)->type_name);
2425   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2426 
2427   ierr = PetscLogEventBegin(MAT_LUFactorSymbolic,mat,row,col,0);CHKERRQ(ierr);
2428   ierr = (fact->ops->lufactorsymbolic)(fact,mat,row,col,info);CHKERRQ(ierr);
2429   ierr = PetscLogEventEnd(MAT_LUFactorSymbolic,mat,row,col,0);CHKERRQ(ierr);
2430   ierr = PetscObjectStateIncrease((PetscObject)fact);CHKERRQ(ierr);
2431   PetscFunctionReturn(0);
2432 }
2433 
2434 #undef __FUNCT__
2435 #define __FUNCT__ "MatLUFactorNumeric"
2436 /*@C
2437    MatLUFactorNumeric - Performs numeric LU factorization of a matrix.
2438    Call this routine after first calling MatLUFactorSymbolic().
2439 
2440    Collective on Mat
2441 
2442    Input Parameters:
2443 +  fact - the factor matrix obtained with MatGetFactor()
2444 .  mat - the matrix
2445 -  info - options for factorization
2446 
2447    Notes:
2448    See MatLUFactor() for in-place factorization.  See
2449    MatCholeskyFactorNumeric() for the symmetric, positive definite case.
2450 
2451    Most users should employ the simplified KSP interface for linear solvers
2452    instead of working directly with matrix algebra routines such as this.
2453    See, e.g., KSPCreate().
2454 
2455    Level: developer
2456 
2457    Concepts: matrices^LU numeric factorization
2458 
2459 .seealso: MatLUFactorSymbolic(), MatLUFactor(), MatCholeskyFactor()
2460 
2461     Developer Note: fortran interface is not autogenerated as the f90
2462     interface defintion cannot be generated correctly [due to MatFactorInfo]
2463 
2464 @*/
2465 PetscErrorCode PETSCMAT_DLLEXPORT MatLUFactorNumeric(Mat fact,Mat mat,const MatFactorInfo *info)
2466 {
2467   PetscErrorCode ierr;
2468 
2469   PetscFunctionBegin;
2470   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2471   PetscValidType(mat,1);
2472   PetscValidPointer(fact,2);
2473   PetscValidHeaderSpecific(fact,MAT_COOKIE,2);
2474   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2475   if (mat->rmap->N != (fact)->rmap->N || mat->cmap->N != (fact)->cmap->N) {
2476     SETERRQ4(PETSC_ERR_ARG_SIZ,"Mat mat,Mat fact: global dimensions are different %D should = %D %D should = %D",mat->rmap->N,(fact)->rmap->N,mat->cmap->N,(fact)->cmap->N);
2477   }
2478   if (!(fact)->ops->lufactornumeric) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2479   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2480   ierr = PetscLogEventBegin(MAT_LUFactorNumeric,mat,fact,0,0);CHKERRQ(ierr);
2481   ierr = (fact->ops->lufactornumeric)(fact,mat,info);CHKERRQ(ierr);
2482   ierr = PetscLogEventEnd(MAT_LUFactorNumeric,mat,fact,0,0);CHKERRQ(ierr);
2483 
2484   ierr = MatView_Private(fact);CHKERRQ(ierr);
2485   ierr = PetscObjectStateIncrease((PetscObject)fact);CHKERRQ(ierr);
2486   PetscFunctionReturn(0);
2487 }
2488 
2489 #undef __FUNCT__
2490 #define __FUNCT__ "MatCholeskyFactor"
2491 /*@C
2492    MatCholeskyFactor - Performs in-place Cholesky factorization of a
2493    symmetric matrix.
2494 
2495    Collective on Mat
2496 
2497    Input Parameters:
2498 +  mat - the matrix
2499 .  perm - row and column permutations
2500 -  f - expected fill as ratio of original fill
2501 
2502    Notes:
2503    See MatLUFactor() for the nonsymmetric case.  See also
2504    MatCholeskyFactorSymbolic(), and MatCholeskyFactorNumeric().
2505 
2506    Most users should employ the simplified KSP interface for linear solvers
2507    instead of working directly with matrix algebra routines such as this.
2508    See, e.g., KSPCreate().
2509 
2510    Level: developer
2511 
2512    Concepts: matrices^Cholesky factorization
2513 
2514 .seealso: MatLUFactor(), MatCholeskyFactorSymbolic(), MatCholeskyFactorNumeric()
2515           MatGetOrdering()
2516 
2517     Developer Note: fortran interface is not autogenerated as the f90
2518     interface defintion cannot be generated correctly [due to MatFactorInfo]
2519 
2520 @*/
2521 PetscErrorCode PETSCMAT_DLLEXPORT MatCholeskyFactor(Mat mat,IS perm,const MatFactorInfo *info)
2522 {
2523   PetscErrorCode ierr;
2524 
2525   PetscFunctionBegin;
2526   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2527   PetscValidType(mat,1);
2528   PetscValidHeaderSpecific(perm,IS_COOKIE,2);
2529   PetscValidPointer(info,3);
2530   if (mat->rmap->N != mat->cmap->N) SETERRQ(PETSC_ERR_ARG_WRONG,"Matrix must be square");
2531   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2532   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2533   if (!mat->ops->choleskyfactor) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2534   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2535 
2536   ierr = PetscLogEventBegin(MAT_CholeskyFactor,mat,perm,0,0);CHKERRQ(ierr);
2537   ierr = (*mat->ops->choleskyfactor)(mat,perm,info);CHKERRQ(ierr);
2538   ierr = PetscLogEventEnd(MAT_CholeskyFactor,mat,perm,0,0);CHKERRQ(ierr);
2539   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
2540   PetscFunctionReturn(0);
2541 }
2542 
2543 #undef __FUNCT__
2544 #define __FUNCT__ "MatCholeskyFactorSymbolic"
2545 /*@C
2546    MatCholeskyFactorSymbolic - Performs symbolic Cholesky factorization
2547    of a symmetric matrix.
2548 
2549    Collective on Mat
2550 
2551    Input Parameters:
2552 +  fact - the factor matrix obtained with MatGetFactor()
2553 .  mat - the matrix
2554 .  perm - row and column permutations
2555 -  info - options for factorization, includes
2556 $          fill - expected fill as ratio of original fill.
2557 $          dtcol - pivot tolerance (0 no pivot, 1 full column pivoting)
2558 $                   Run with the option -info to determine an optimal value to use
2559 
2560    Notes:
2561    See MatLUFactorSymbolic() for the nonsymmetric case.  See also
2562    MatCholeskyFactor() and MatCholeskyFactorNumeric().
2563 
2564    Most users should employ the simplified KSP interface for linear solvers
2565    instead of working directly with matrix algebra routines such as this.
2566    See, e.g., KSPCreate().
2567 
2568    Level: developer
2569 
2570    Concepts: matrices^Cholesky symbolic factorization
2571 
2572 .seealso: MatLUFactorSymbolic(), MatCholeskyFactor(), MatCholeskyFactorNumeric()
2573           MatGetOrdering()
2574 
2575     Developer Note: fortran interface is not autogenerated as the f90
2576     interface defintion cannot be generated correctly [due to MatFactorInfo]
2577 
2578 @*/
2579 PetscErrorCode PETSCMAT_DLLEXPORT MatCholeskyFactorSymbolic(Mat fact,Mat mat,IS perm,const MatFactorInfo *info)
2580 {
2581   PetscErrorCode ierr;
2582 
2583   PetscFunctionBegin;
2584   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2585   PetscValidType(mat,1);
2586   if (perm) PetscValidHeaderSpecific(perm,IS_COOKIE,2);
2587   PetscValidPointer(info,3);
2588   PetscValidPointer(fact,4);
2589   if (mat->rmap->N != mat->cmap->N) SETERRQ(PETSC_ERR_ARG_WRONG,"Matrix must be square");
2590   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2591   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2592   if (!(fact)->ops->choleskyfactorsymbolic) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2593   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2594 
2595   ierr = PetscLogEventBegin(MAT_CholeskyFactorSymbolic,mat,perm,0,0);CHKERRQ(ierr);
2596   ierr = (fact->ops->choleskyfactorsymbolic)(fact,mat,perm,info);CHKERRQ(ierr);
2597   ierr = PetscLogEventEnd(MAT_CholeskyFactorSymbolic,mat,perm,0,0);CHKERRQ(ierr);
2598   ierr = PetscObjectStateIncrease((PetscObject)fact);CHKERRQ(ierr);
2599   PetscFunctionReturn(0);
2600 }
2601 
2602 #undef __FUNCT__
2603 #define __FUNCT__ "MatCholeskyFactorNumeric"
2604 /*@C
2605    MatCholeskyFactorNumeric - Performs numeric Cholesky factorization
2606    of a symmetric matrix. Call this routine after first calling
2607    MatCholeskyFactorSymbolic().
2608 
2609    Collective on Mat
2610 
2611    Input Parameters:
2612 +  fact - the factor matrix obtained with MatGetFactor()
2613 .  mat - the initial matrix
2614 .  info - options for factorization
2615 -  fact - the symbolic factor of mat
2616 
2617 
2618    Notes:
2619    Most users should employ the simplified KSP interface for linear solvers
2620    instead of working directly with matrix algebra routines such as this.
2621    See, e.g., KSPCreate().
2622 
2623    Level: developer
2624 
2625    Concepts: matrices^Cholesky numeric factorization
2626 
2627 .seealso: MatCholeskyFactorSymbolic(), MatCholeskyFactor(), MatLUFactorNumeric()
2628 
2629     Developer Note: fortran interface is not autogenerated as the f90
2630     interface defintion cannot be generated correctly [due to MatFactorInfo]
2631 
2632 @*/
2633 PetscErrorCode PETSCMAT_DLLEXPORT MatCholeskyFactorNumeric(Mat fact,Mat mat,const MatFactorInfo *info)
2634 {
2635   PetscErrorCode ierr;
2636 
2637   PetscFunctionBegin;
2638   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2639   PetscValidType(mat,1);
2640   PetscValidPointer(fact,2);
2641   PetscValidHeaderSpecific(fact,MAT_COOKIE,2);
2642   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2643   if (!(fact)->ops->choleskyfactornumeric) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2644   if (mat->rmap->N != (fact)->rmap->N || mat->cmap->N != (fact)->cmap->N) {
2645     SETERRQ4(PETSC_ERR_ARG_SIZ,"Mat mat,Mat fact: global dim %D should = %D %D should = %D",mat->rmap->N,(fact)->rmap->N,mat->cmap->N,(fact)->cmap->N);
2646   }
2647   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2648 
2649   ierr = PetscLogEventBegin(MAT_CholeskyFactorNumeric,mat,fact,0,0);CHKERRQ(ierr);
2650   ierr = (fact->ops->choleskyfactornumeric)(fact,mat,info);CHKERRQ(ierr);
2651   ierr = PetscLogEventEnd(MAT_CholeskyFactorNumeric,mat,fact,0,0);CHKERRQ(ierr);
2652 
2653   ierr = MatView_Private(fact);CHKERRQ(ierr);
2654   ierr = PetscObjectStateIncrease((PetscObject)fact);CHKERRQ(ierr);
2655   PetscFunctionReturn(0);
2656 }
2657 
2658 /* ----------------------------------------------------------------*/
2659 #undef __FUNCT__
2660 #define __FUNCT__ "MatSolve"
2661 /*@
2662    MatSolve - Solves A x = b, given a factored matrix.
2663 
2664    Collective on Mat and Vec
2665 
2666    Input Parameters:
2667 +  mat - the factored matrix
2668 -  b - the right-hand-side vector
2669 
2670    Output Parameter:
2671 .  x - the result vector
2672 
2673    Notes:
2674    The vectors b and x cannot be the same.  I.e., one cannot
2675    call MatSolve(A,x,x).
2676 
2677    Notes:
2678    Most users should employ the simplified KSP interface for linear solvers
2679    instead of working directly with matrix algebra routines such as this.
2680    See, e.g., KSPCreate().
2681 
2682    Level: developer
2683 
2684    Concepts: matrices^triangular solves
2685 
2686 .seealso: MatSolveAdd(), MatSolveTranspose(), MatSolveTransposeAdd()
2687 @*/
2688 PetscErrorCode PETSCMAT_DLLEXPORT MatSolve(Mat mat,Vec b,Vec x)
2689 {
2690   PetscErrorCode ierr;
2691 
2692   PetscFunctionBegin;
2693   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2694   PetscValidType(mat,1);
2695   PetscValidHeaderSpecific(b,VEC_COOKIE,2);
2696   PetscValidHeaderSpecific(x,VEC_COOKIE,3);
2697   PetscCheckSameComm(mat,1,b,2);
2698   PetscCheckSameComm(mat,1,x,3);
2699   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
2700   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2701   if (mat->cmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
2702   if (mat->rmap->N != b->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: global dim %D %D",mat->rmap->N,b->map->N);
2703   if (mat->rmap->n != b->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: local dim %D %D",mat->rmap->n,b->map->n);
2704   if (!mat->rmap->N && !mat->cmap->N) PetscFunctionReturn(0);
2705   if (!mat->ops->solve) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2706   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2707 
2708   ierr = PetscLogEventBegin(MAT_Solve,mat,b,x,0);CHKERRQ(ierr);
2709   ierr = (*mat->ops->solve)(mat,b,x);CHKERRQ(ierr);
2710   ierr = PetscLogEventEnd(MAT_Solve,mat,b,x,0);CHKERRQ(ierr);
2711   ierr = PetscObjectStateIncrease((PetscObject)x);CHKERRQ(ierr);
2712   PetscFunctionReturn(0);
2713 }
2714 
2715 #undef __FUNCT__
2716 #define __FUNCT__ "MatMatSolve_Basic"
2717 PetscErrorCode PETSCMAT_DLLEXPORT MatMatSolve_Basic(Mat A,Mat B,Mat X)
2718 {
2719   PetscErrorCode ierr;
2720   Vec            b,x;
2721   PetscInt       m,N,i;
2722   PetscScalar    *bb,*xx;
2723 
2724   PetscFunctionBegin;
2725   ierr = MatGetArray(B,&bb);CHKERRQ(ierr);
2726   ierr = MatGetArray(X,&xx);CHKERRQ(ierr);
2727   ierr = MatGetLocalSize(B,&m,PETSC_NULL);CHKERRQ(ierr);  /* number local rows */
2728   ierr = MatGetSize(B,PETSC_NULL,&N);CHKERRQ(ierr);       /* total columns in dense matrix */
2729   ierr = MatGetVecs(B,&x,&b);CHKERRQ(ierr);
2730   for (i=0; i<N; i++) {
2731     ierr = VecPlaceArray(b,bb + i*m);CHKERRQ(ierr);
2732     ierr = VecPlaceArray(x,xx + i*m);CHKERRQ(ierr);
2733     ierr = MatSolve(A,b,x);CHKERRQ(ierr);
2734     ierr = VecResetArray(x);CHKERRQ(ierr);
2735     ierr = VecResetArray(b);CHKERRQ(ierr);
2736   }
2737   ierr = VecDestroy(b);CHKERRQ(ierr);
2738   ierr = VecDestroy(x);CHKERRQ(ierr);
2739   ierr = MatRestoreArray(B,&bb);CHKERRQ(ierr);
2740   ierr = MatRestoreArray(X,&xx);CHKERRQ(ierr);
2741   PetscFunctionReturn(0);
2742 }
2743 
2744 #undef __FUNCT__
2745 #define __FUNCT__ "MatMatSolve"
2746 /*@
2747    MatMatSolve - Solves A X = B, given a factored matrix.
2748 
2749    Collective on Mat
2750 
2751    Input Parameters:
2752 +  mat - the factored matrix
2753 -  B - the right-hand-side matrix  (dense matrix)
2754 
2755    Output Parameter:
2756 .  X - the result matrix (dense matrix)
2757 
2758    Notes:
2759    The matrices b and x cannot be the same.  I.e., one cannot
2760    call MatMatSolve(A,x,x).
2761 
2762    Notes:
2763    Most users should usually employ the simplified KSP interface for linear solvers
2764    instead of working directly with matrix algebra routines such as this.
2765    See, e.g., KSPCreate(). However KSP can only solve for one vector (column of X)
2766    at a time.
2767 
2768    Level: developer
2769 
2770    Concepts: matrices^triangular solves
2771 
2772 .seealso: MatMatSolveAdd(), MatMatSolveTranspose(), MatMatSolveTransposeAdd(), MatLUFactor(), MatCholeskyFactor()
2773 @*/
2774 PetscErrorCode PETSCMAT_DLLEXPORT MatMatSolve(Mat A,Mat B,Mat X)
2775 {
2776   PetscErrorCode ierr;
2777 
2778   PetscFunctionBegin;
2779   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
2780   PetscValidType(A,1);
2781   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
2782   PetscValidHeaderSpecific(X,MAT_COOKIE,3);
2783   PetscCheckSameComm(A,1,B,2);
2784   PetscCheckSameComm(A,1,X,3);
2785   if (X == B) SETERRQ(PETSC_ERR_ARG_IDN,"X and B must be different matrices");
2786   if (!A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2787   if (A->cmap->N != X->rmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat A,Mat X: global dim %D %D",A->cmap->N,X->rmap->N);
2788   if (A->rmap->N != B->rmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat A,Mat B: global dim %D %D",A->rmap->N,B->rmap->N);
2789   if (A->rmap->n != B->rmap->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat A,Mat B: local dim %D %D",A->rmap->n,B->rmap->n);
2790   if (!A->rmap->N && !A->cmap->N) PetscFunctionReturn(0);
2791   ierr = MatPreallocated(A);CHKERRQ(ierr);
2792 
2793   ierr = PetscLogEventBegin(MAT_MatSolve,A,B,X,0);CHKERRQ(ierr);
2794   if (!A->ops->matsolve) {
2795     ierr = PetscInfo1(A,"Mat type %s using basic MatMatSolve",((PetscObject)A)->type_name);CHKERRQ(ierr);
2796     ierr = MatMatSolve_Basic(A,B,X);CHKERRQ(ierr);
2797   } else {
2798     ierr = (*A->ops->matsolve)(A,B,X);CHKERRQ(ierr);
2799   }
2800   ierr = PetscLogEventEnd(MAT_MatSolve,A,B,X,0);CHKERRQ(ierr);
2801   ierr = PetscObjectStateIncrease((PetscObject)X);CHKERRQ(ierr);
2802   PetscFunctionReturn(0);
2803 }
2804 
2805 
2806 #undef __FUNCT__
2807 #define __FUNCT__ "MatForwardSolve"
2808 /* @
2809    MatForwardSolve - Solves L x = b, given a factored matrix, A = LU, or
2810                             U^T*D^(1/2) x = b, given a factored symmetric matrix, A = U^T*D*U,
2811 
2812    Collective on Mat and Vec
2813 
2814    Input Parameters:
2815 +  mat - the factored matrix
2816 -  b - the right-hand-side vector
2817 
2818    Output Parameter:
2819 .  x - the result vector
2820 
2821    Notes:
2822    MatSolve() should be used for most applications, as it performs
2823    a forward solve followed by a backward solve.
2824 
2825    The vectors b and x cannot be the same,  i.e., one cannot
2826    call MatForwardSolve(A,x,x).
2827 
2828    For matrix in seqsbaij format with block size larger than 1,
2829    the diagonal blocks are not implemented as D = D^(1/2) * D^(1/2) yet.
2830    MatForwardSolve() solves U^T*D y = b, and
2831    MatBackwardSolve() solves U x = y.
2832    Thus they do not provide a symmetric preconditioner.
2833 
2834    Most users should employ the simplified KSP interface for linear solvers
2835    instead of working directly with matrix algebra routines such as this.
2836    See, e.g., KSPCreate().
2837 
2838    Level: developer
2839 
2840    Concepts: matrices^forward solves
2841 
2842 .seealso: MatSolve(), MatBackwardSolve()
2843 @ */
2844 PetscErrorCode PETSCMAT_DLLEXPORT MatForwardSolve(Mat mat,Vec b,Vec x)
2845 {
2846   PetscErrorCode ierr;
2847 
2848   PetscFunctionBegin;
2849   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2850   PetscValidType(mat,1);
2851   PetscValidHeaderSpecific(b,VEC_COOKIE,2);
2852   PetscValidHeaderSpecific(x,VEC_COOKIE,3);
2853   PetscCheckSameComm(mat,1,b,2);
2854   PetscCheckSameComm(mat,1,x,3);
2855   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
2856   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2857   if (!mat->ops->forwardsolve) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2858   if (mat->cmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
2859   if (mat->rmap->N != b->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: global dim %D %D",mat->rmap->N,b->map->N);
2860   if (mat->rmap->n != b->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: local dim %D %D",mat->rmap->n,b->map->n);
2861   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2862   ierr = PetscLogEventBegin(MAT_ForwardSolve,mat,b,x,0);CHKERRQ(ierr);
2863   ierr = (*mat->ops->forwardsolve)(mat,b,x);CHKERRQ(ierr);
2864   ierr = PetscLogEventEnd(MAT_ForwardSolve,mat,b,x,0);CHKERRQ(ierr);
2865   ierr = PetscObjectStateIncrease((PetscObject)x);CHKERRQ(ierr);
2866   PetscFunctionReturn(0);
2867 }
2868 
2869 #undef __FUNCT__
2870 #define __FUNCT__ "MatBackwardSolve"
2871 /* @
2872    MatBackwardSolve - Solves U x = b, given a factored matrix, A = LU.
2873                              D^(1/2) U x = b, given a factored symmetric matrix, A = U^T*D*U,
2874 
2875    Collective on Mat and Vec
2876 
2877    Input Parameters:
2878 +  mat - the factored matrix
2879 -  b - the right-hand-side vector
2880 
2881    Output Parameter:
2882 .  x - the result vector
2883 
2884    Notes:
2885    MatSolve() should be used for most applications, as it performs
2886    a forward solve followed by a backward solve.
2887 
2888    The vectors b and x cannot be the same.  I.e., one cannot
2889    call MatBackwardSolve(A,x,x).
2890 
2891    For matrix in seqsbaij format with block size larger than 1,
2892    the diagonal blocks are not implemented as D = D^(1/2) * D^(1/2) yet.
2893    MatForwardSolve() solves U^T*D y = b, and
2894    MatBackwardSolve() solves U x = y.
2895    Thus they do not provide a symmetric preconditioner.
2896 
2897    Most users should employ the simplified KSP interface for linear solvers
2898    instead of working directly with matrix algebra routines such as this.
2899    See, e.g., KSPCreate().
2900 
2901    Level: developer
2902 
2903    Concepts: matrices^backward solves
2904 
2905 .seealso: MatSolve(), MatForwardSolve()
2906 @ */
2907 PetscErrorCode PETSCMAT_DLLEXPORT MatBackwardSolve(Mat mat,Vec b,Vec x)
2908 {
2909   PetscErrorCode ierr;
2910 
2911   PetscFunctionBegin;
2912   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2913   PetscValidType(mat,1);
2914   PetscValidHeaderSpecific(b,VEC_COOKIE,2);
2915   PetscValidHeaderSpecific(x,VEC_COOKIE,3);
2916   PetscCheckSameComm(mat,1,b,2);
2917   PetscCheckSameComm(mat,1,x,3);
2918   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
2919   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2920   if (!mat->ops->backwardsolve) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2921   if (mat->cmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
2922   if (mat->rmap->N != b->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: global dim %D %D",mat->rmap->N,b->map->N);
2923   if (mat->rmap->n != b->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: local dim %D %D",mat->rmap->n,b->map->n);
2924   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2925 
2926   ierr = PetscLogEventBegin(MAT_BackwardSolve,mat,b,x,0);CHKERRQ(ierr);
2927   ierr = (*mat->ops->backwardsolve)(mat,b,x);CHKERRQ(ierr);
2928   ierr = PetscLogEventEnd(MAT_BackwardSolve,mat,b,x,0);CHKERRQ(ierr);
2929   ierr = PetscObjectStateIncrease((PetscObject)x);CHKERRQ(ierr);
2930   PetscFunctionReturn(0);
2931 }
2932 
2933 #undef __FUNCT__
2934 #define __FUNCT__ "MatSolveAdd"
2935 /*@
2936    MatSolveAdd - Computes x = y + inv(A)*b, given a factored matrix.
2937 
2938    Collective on Mat and Vec
2939 
2940    Input Parameters:
2941 +  mat - the factored matrix
2942 .  b - the right-hand-side vector
2943 -  y - the vector to be added to
2944 
2945    Output Parameter:
2946 .  x - the result vector
2947 
2948    Notes:
2949    The vectors b and x cannot be the same.  I.e., one cannot
2950    call MatSolveAdd(A,x,y,x).
2951 
2952    Most users should employ the simplified KSP interface for linear solvers
2953    instead of working directly with matrix algebra routines such as this.
2954    See, e.g., KSPCreate().
2955 
2956    Level: developer
2957 
2958    Concepts: matrices^triangular solves
2959 
2960 .seealso: MatSolve(), MatSolveTranspose(), MatSolveTransposeAdd()
2961 @*/
2962 PetscErrorCode PETSCMAT_DLLEXPORT MatSolveAdd(Mat mat,Vec b,Vec y,Vec x)
2963 {
2964   PetscScalar    one = 1.0;
2965   Vec            tmp;
2966   PetscErrorCode ierr;
2967 
2968   PetscFunctionBegin;
2969   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2970   PetscValidType(mat,1);
2971   PetscValidHeaderSpecific(y,VEC_COOKIE,2);
2972   PetscValidHeaderSpecific(b,VEC_COOKIE,3);
2973   PetscValidHeaderSpecific(x,VEC_COOKIE,4);
2974   PetscCheckSameComm(mat,1,b,2);
2975   PetscCheckSameComm(mat,1,y,2);
2976   PetscCheckSameComm(mat,1,x,3);
2977   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
2978   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2979   if (mat->cmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
2980   if (mat->rmap->N != b->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: global dim %D %D",mat->rmap->N,b->map->N);
2981   if (mat->rmap->N != y->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec y: global dim %D %D",mat->rmap->N,y->map->N);
2982   if (mat->rmap->n != b->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: local dim %D %D",mat->rmap->n,b->map->n);
2983   if (x->map->n != y->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Vec x,Vec y: local dim %D %D",x->map->n,y->map->n);
2984   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2985 
2986   ierr = PetscLogEventBegin(MAT_SolveAdd,mat,b,x,y);CHKERRQ(ierr);
2987   if (mat->ops->solveadd)  {
2988     ierr = (*mat->ops->solveadd)(mat,b,y,x);CHKERRQ(ierr);
2989   } else {
2990     /* do the solve then the add manually */
2991     if (x != y) {
2992       ierr = MatSolve(mat,b,x);CHKERRQ(ierr);
2993       ierr = VecAXPY(x,one,y);CHKERRQ(ierr);
2994     } else {
2995       ierr = VecDuplicate(x,&tmp);CHKERRQ(ierr);
2996       ierr = PetscLogObjectParent(mat,tmp);CHKERRQ(ierr);
2997       ierr = VecCopy(x,tmp);CHKERRQ(ierr);
2998       ierr = MatSolve(mat,b,x);CHKERRQ(ierr);
2999       ierr = VecAXPY(x,one,tmp);CHKERRQ(ierr);
3000       ierr = VecDestroy(tmp);CHKERRQ(ierr);
3001     }
3002   }
3003   ierr = PetscLogEventEnd(MAT_SolveAdd,mat,b,x,y);CHKERRQ(ierr);
3004   ierr = PetscObjectStateIncrease((PetscObject)x);CHKERRQ(ierr);
3005   PetscFunctionReturn(0);
3006 }
3007 
3008 #undef __FUNCT__
3009 #define __FUNCT__ "MatSolveTranspose"
3010 /*@
3011    MatSolveTranspose - Solves A' x = b, given a factored matrix.
3012 
3013    Collective on Mat and Vec
3014 
3015    Input Parameters:
3016 +  mat - the factored matrix
3017 -  b - the right-hand-side vector
3018 
3019    Output Parameter:
3020 .  x - the result vector
3021 
3022    Notes:
3023    The vectors b and x cannot be the same.  I.e., one cannot
3024    call MatSolveTranspose(A,x,x).
3025 
3026    Most users should employ the simplified KSP interface for linear solvers
3027    instead of working directly with matrix algebra routines such as this.
3028    See, e.g., KSPCreate().
3029 
3030    Level: developer
3031 
3032    Concepts: matrices^triangular solves
3033 
3034 .seealso: MatSolve(), MatSolveAdd(), MatSolveTransposeAdd()
3035 @*/
3036 PetscErrorCode PETSCMAT_DLLEXPORT MatSolveTranspose(Mat mat,Vec b,Vec x)
3037 {
3038   PetscErrorCode ierr;
3039 
3040   PetscFunctionBegin;
3041   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3042   PetscValidType(mat,1);
3043   PetscValidHeaderSpecific(b,VEC_COOKIE,2);
3044   PetscValidHeaderSpecific(x,VEC_COOKIE,3);
3045   PetscCheckSameComm(mat,1,b,2);
3046   PetscCheckSameComm(mat,1,x,3);
3047   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
3048   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
3049   if (!mat->ops->solvetranspose) SETERRQ1(PETSC_ERR_SUP,"Matrix type %s",((PetscObject)mat)->type_name);
3050   if (mat->rmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->rmap->N,x->map->N);
3051   if (mat->cmap->N != b->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: global dim %D %D",mat->cmap->N,b->map->N);
3052   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3053   ierr = PetscLogEventBegin(MAT_SolveTranspose,mat,b,x,0);CHKERRQ(ierr);
3054   ierr = (*mat->ops->solvetranspose)(mat,b,x);CHKERRQ(ierr);
3055   ierr = PetscLogEventEnd(MAT_SolveTranspose,mat,b,x,0);CHKERRQ(ierr);
3056   ierr = PetscObjectStateIncrease((PetscObject)x);CHKERRQ(ierr);
3057   PetscFunctionReturn(0);
3058 }
3059 
3060 #undef __FUNCT__
3061 #define __FUNCT__ "MatSolveTransposeAdd"
3062 /*@
3063    MatSolveTransposeAdd - Computes x = y + inv(Transpose(A)) b, given a
3064                       factored matrix.
3065 
3066    Collective on Mat and Vec
3067 
3068    Input Parameters:
3069 +  mat - the factored matrix
3070 .  b - the right-hand-side vector
3071 -  y - the vector to be added to
3072 
3073    Output Parameter:
3074 .  x - the result vector
3075 
3076    Notes:
3077    The vectors b and x cannot be the same.  I.e., one cannot
3078    call MatSolveTransposeAdd(A,x,y,x).
3079 
3080    Most users should employ the simplified KSP interface for linear solvers
3081    instead of working directly with matrix algebra routines such as this.
3082    See, e.g., KSPCreate().
3083 
3084    Level: developer
3085 
3086    Concepts: matrices^triangular solves
3087 
3088 .seealso: MatSolve(), MatSolveAdd(), MatSolveTranspose()
3089 @*/
3090 PetscErrorCode PETSCMAT_DLLEXPORT MatSolveTransposeAdd(Mat mat,Vec b,Vec y,Vec x)
3091 {
3092   PetscScalar    one = 1.0;
3093   PetscErrorCode ierr;
3094   Vec            tmp;
3095 
3096   PetscFunctionBegin;
3097   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3098   PetscValidType(mat,1);
3099   PetscValidHeaderSpecific(y,VEC_COOKIE,2);
3100   PetscValidHeaderSpecific(b,VEC_COOKIE,3);
3101   PetscValidHeaderSpecific(x,VEC_COOKIE,4);
3102   PetscCheckSameComm(mat,1,b,2);
3103   PetscCheckSameComm(mat,1,y,3);
3104   PetscCheckSameComm(mat,1,x,4);
3105   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
3106   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
3107   if (mat->rmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->rmap->N,x->map->N);
3108   if (mat->cmap->N != b->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: global dim %D %D",mat->cmap->N,b->map->N);
3109   if (mat->cmap->N != y->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec y: global dim %D %D",mat->cmap->N,y->map->N);
3110   if (x->map->n != y->map->n)   SETERRQ2(PETSC_ERR_ARG_SIZ,"Vec x,Vec y: local dim %D %D",x->map->n,y->map->n);
3111   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3112 
3113   ierr = PetscLogEventBegin(MAT_SolveTransposeAdd,mat,b,x,y);CHKERRQ(ierr);
3114   if (mat->ops->solvetransposeadd) {
3115     ierr = (*mat->ops->solvetransposeadd)(mat,b,y,x);CHKERRQ(ierr);
3116   } else {
3117     /* do the solve then the add manually */
3118     if (x != y) {
3119       ierr = MatSolveTranspose(mat,b,x);CHKERRQ(ierr);
3120       ierr = VecAXPY(x,one,y);CHKERRQ(ierr);
3121     } else {
3122       ierr = VecDuplicate(x,&tmp);CHKERRQ(ierr);
3123       ierr = PetscLogObjectParent(mat,tmp);CHKERRQ(ierr);
3124       ierr = VecCopy(x,tmp);CHKERRQ(ierr);
3125       ierr = MatSolveTranspose(mat,b,x);CHKERRQ(ierr);
3126       ierr = VecAXPY(x,one,tmp);CHKERRQ(ierr);
3127       ierr = VecDestroy(tmp);CHKERRQ(ierr);
3128     }
3129   }
3130   ierr = PetscLogEventEnd(MAT_SolveTransposeAdd,mat,b,x,y);CHKERRQ(ierr);
3131   ierr = PetscObjectStateIncrease((PetscObject)x);CHKERRQ(ierr);
3132   PetscFunctionReturn(0);
3133 }
3134 /* ----------------------------------------------------------------*/
3135 
3136 #undef __FUNCT__
3137 #define __FUNCT__ "MatRelax"
3138 /*@
3139    MatRelax - Computes relaxation (SOR, Gauss-Seidel) sweeps.
3140 
3141    Collective on Mat and Vec
3142 
3143    Input Parameters:
3144 +  mat - the matrix
3145 .  b - the right hand side
3146 .  omega - the relaxation factor
3147 .  flag - flag indicating the type of SOR (see below)
3148 .  shift -  diagonal shift
3149 .  its - the number of iterations
3150 -  lits - the number of local iterations
3151 
3152    Output Parameters:
3153 .  x - the solution (can contain an initial guess)
3154 
3155    SOR Flags:
3156 .     SOR_FORWARD_SWEEP - forward SOR
3157 .     SOR_BACKWARD_SWEEP - backward SOR
3158 .     SOR_SYMMETRIC_SWEEP - SSOR (symmetric SOR)
3159 .     SOR_LOCAL_FORWARD_SWEEP - local forward SOR
3160 .     SOR_LOCAL_BACKWARD_SWEEP - local forward SOR
3161 .     SOR_LOCAL_SYMMETRIC_SWEEP - local SSOR
3162 .     SOR_APPLY_UPPER, SOR_APPLY_LOWER - applies
3163          upper/lower triangular part of matrix to
3164          vector (with omega)
3165 .     SOR_ZERO_INITIAL_GUESS - zero initial guess
3166 
3167    Notes:
3168    SOR_LOCAL_FORWARD_SWEEP, SOR_LOCAL_BACKWARD_SWEEP, and
3169    SOR_LOCAL_SYMMETRIC_SWEEP perform separate independent smoothings
3170    on each processor.
3171 
3172    Application programmers will not generally use MatRelax() directly,
3173    but instead will employ the KSP/PC interface.
3174 
3175    Notes for Advanced Users:
3176    The flags are implemented as bitwise inclusive or operations.
3177    For example, use (SOR_ZERO_INITIAL_GUESS | SOR_SYMMETRIC_SWEEP)
3178    to specify a zero initial guess for SSOR.
3179 
3180    Most users should employ the simplified KSP interface for linear solvers
3181    instead of working directly with matrix algebra routines such as this.
3182    See, e.g., KSPCreate().
3183 
3184    See also, MatPBRelax(). This routine will automatically call the point block
3185    version if the point version is not available.
3186 
3187    Level: developer
3188 
3189    Concepts: matrices^relaxation
3190    Concepts: matrices^SOR
3191    Concepts: matrices^Gauss-Seidel
3192 
3193 @*/
3194 PetscErrorCode PETSCMAT_DLLEXPORT MatRelax(Mat mat,Vec b,PetscReal omega,MatSORType flag,PetscReal shift,PetscInt its,PetscInt lits,Vec x)
3195 {
3196   PetscErrorCode ierr;
3197 
3198   PetscFunctionBegin;
3199   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3200   PetscValidType(mat,1);
3201   PetscValidHeaderSpecific(b,VEC_COOKIE,2);
3202   PetscValidHeaderSpecific(x,VEC_COOKIE,8);
3203   PetscCheckSameComm(mat,1,b,2);
3204   PetscCheckSameComm(mat,1,x,8);
3205   if (!mat->ops->relax && !mat->ops->pbrelax) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3206   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3207   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3208   if (mat->cmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
3209   if (mat->rmap->N != b->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: global dim %D %D",mat->rmap->N,b->map->N);
3210   if (mat->rmap->n != b->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: local dim %D %D",mat->rmap->n,b->map->n);
3211   if (its <= 0) SETERRQ1(PETSC_ERR_ARG_WRONG,"Relaxation requires global its %D positive",its);
3212   if (lits <= 0) SETERRQ1(PETSC_ERR_ARG_WRONG,"Relaxation requires local its %D positive",lits);
3213 
3214   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3215   ierr = PetscLogEventBegin(MAT_Relax,mat,b,x,0);CHKERRQ(ierr);
3216   if (mat->ops->relax) {
3217     ierr =(*mat->ops->relax)(mat,b,omega,flag,shift,its,lits,x);CHKERRQ(ierr);
3218   } else {
3219     ierr =(*mat->ops->pbrelax)(mat,b,omega,flag,shift,its,lits,x);CHKERRQ(ierr);
3220   }
3221   ierr = PetscLogEventEnd(MAT_Relax,mat,b,x,0);CHKERRQ(ierr);
3222   ierr = PetscObjectStateIncrease((PetscObject)x);CHKERRQ(ierr);
3223   PetscFunctionReturn(0);
3224 }
3225 
3226 #undef __FUNCT__
3227 #define __FUNCT__ "MatPBRelax"
3228 /*@
3229    MatPBRelax - Computes relaxation (SOR, Gauss-Seidel) sweeps.
3230 
3231    Collective on Mat and Vec
3232 
3233    See MatRelax() for usage. This is called by MatRelax() when appropriate so need not be called by users.
3234 
3235    For multi-component PDEs where the Jacobian is stored in a point block format
3236    (with the PETSc BAIJ matrix formats) the relaxation is done one point block at
3237    a time. That is, the small (for example, 4 by 4) blocks along the diagonal are solved
3238    simultaneously (that is a 4 by 4 linear solve is done) to update all the values at a point.
3239 
3240    Level: developer
3241 
3242 @*/
3243 PetscErrorCode PETSCMAT_DLLEXPORT MatPBRelax(Mat mat,Vec b,PetscReal omega,MatSORType flag,PetscReal shift,PetscInt its,PetscInt lits,Vec x)
3244 {
3245   PetscErrorCode ierr;
3246 
3247   PetscFunctionBegin;
3248   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3249   PetscValidType(mat,1);
3250   PetscValidHeaderSpecific(b,VEC_COOKIE,2);
3251   PetscValidHeaderSpecific(x,VEC_COOKIE,8);
3252   PetscCheckSameComm(mat,1,b,2);
3253   PetscCheckSameComm(mat,1,x,8);
3254   if (!mat->ops->pbrelax) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3255   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3256   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3257   if (mat->cmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
3258   if (mat->rmap->N != b->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: global dim %D %D",mat->rmap->N,b->map->N);
3259   if (mat->rmap->n != b->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: local dim %D %D",mat->rmap->n,b->map->n);
3260   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3261 
3262   ierr = PetscLogEventBegin(MAT_Relax,mat,b,x,0);CHKERRQ(ierr);
3263   ierr =(*mat->ops->pbrelax)(mat,b,omega,flag,shift,its,lits,x);CHKERRQ(ierr);
3264   ierr = PetscLogEventEnd(MAT_Relax,mat,b,x,0);CHKERRQ(ierr);
3265   ierr = PetscObjectStateIncrease((PetscObject)x);CHKERRQ(ierr);
3266   PetscFunctionReturn(0);
3267 }
3268 
3269 #undef __FUNCT__
3270 #define __FUNCT__ "MatCopy_Basic"
3271 /*
3272       Default matrix copy routine.
3273 */
3274 PetscErrorCode MatCopy_Basic(Mat A,Mat B,MatStructure str)
3275 {
3276   PetscErrorCode    ierr;
3277   PetscInt          i,rstart,rend,nz;
3278   const PetscInt    *cwork;
3279   const PetscScalar *vwork;
3280 
3281   PetscFunctionBegin;
3282   if (B->assembled) {
3283     ierr = MatZeroEntries(B);CHKERRQ(ierr);
3284   }
3285   ierr = MatGetOwnershipRange(A,&rstart,&rend);CHKERRQ(ierr);
3286   for (i=rstart; i<rend; i++) {
3287     ierr = MatGetRow(A,i,&nz,&cwork,&vwork);CHKERRQ(ierr);
3288     ierr = MatSetValues(B,1,&i,nz,cwork,vwork,INSERT_VALUES);CHKERRQ(ierr);
3289     ierr = MatRestoreRow(A,i,&nz,&cwork,&vwork);CHKERRQ(ierr);
3290   }
3291   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3292   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3293   ierr = PetscObjectStateIncrease((PetscObject)B);CHKERRQ(ierr);
3294   PetscFunctionReturn(0);
3295 }
3296 
3297 #undef __FUNCT__
3298 #define __FUNCT__ "MatCopy"
3299 /*@
3300    MatCopy - Copys a matrix to another matrix.
3301 
3302    Collective on Mat
3303 
3304    Input Parameters:
3305 +  A - the matrix
3306 -  str - SAME_NONZERO_PATTERN or DIFFERENT_NONZERO_PATTERN
3307 
3308    Output Parameter:
3309 .  B - where the copy is put
3310 
3311    Notes:
3312    If you use SAME_NONZERO_PATTERN then the two matrices had better have the
3313    same nonzero pattern or the routine will crash.
3314 
3315    MatCopy() copies the matrix entries of a matrix to another existing
3316    matrix (after first zeroing the second matrix).  A related routine is
3317    MatConvert(), which first creates a new matrix and then copies the data.
3318 
3319    Level: intermediate
3320 
3321    Concepts: matrices^copying
3322 
3323 .seealso: MatConvert(), MatDuplicate()
3324 
3325 @*/
3326 PetscErrorCode PETSCMAT_DLLEXPORT MatCopy(Mat A,Mat B,MatStructure str)
3327 {
3328   PetscErrorCode ierr;
3329   PetscInt       i;
3330 
3331   PetscFunctionBegin;
3332   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
3333   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
3334   PetscValidType(A,1);
3335   PetscValidType(B,2);
3336   PetscCheckSameComm(A,1,B,2);
3337   ierr = MatPreallocated(B);CHKERRQ(ierr);
3338   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3339   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3340   if (A->rmap->N != B->rmap->N || A->cmap->N != B->cmap->N) SETERRQ4(PETSC_ERR_ARG_SIZ,"Mat A,Mat B: global dim (%D,%D) (%D,%D)",A->rmap->N,B->rmap->N,A->cmap->N,B->cmap->N);
3341   ierr = MatPreallocated(A);CHKERRQ(ierr);
3342 
3343   ierr = PetscLogEventBegin(MAT_Copy,A,B,0,0);CHKERRQ(ierr);
3344   if (A->ops->copy) {
3345     ierr = (*A->ops->copy)(A,B,str);CHKERRQ(ierr);
3346   } else { /* generic conversion */
3347     ierr = MatCopy_Basic(A,B,str);CHKERRQ(ierr);
3348   }
3349   if (A->mapping) {
3350     if (B->mapping) {ierr = ISLocalToGlobalMappingDestroy(B->mapping);CHKERRQ(ierr);B->mapping = 0;}
3351     ierr = MatSetLocalToGlobalMapping(B,A->mapping);CHKERRQ(ierr);
3352   }
3353   if (A->bmapping) {
3354     if (B->bmapping) {ierr = ISLocalToGlobalMappingDestroy(B->bmapping);CHKERRQ(ierr);B->bmapping = 0;}
3355     ierr = MatSetLocalToGlobalMappingBlock(B,A->mapping);CHKERRQ(ierr);
3356   }
3357 
3358   B->stencil.dim = A->stencil.dim;
3359   B->stencil.noc = A->stencil.noc;
3360   for (i=0; i<=A->stencil.dim; i++) {
3361     B->stencil.dims[i]   = A->stencil.dims[i];
3362     B->stencil.starts[i] = A->stencil.starts[i];
3363   }
3364 
3365   ierr = PetscLogEventEnd(MAT_Copy,A,B,0,0);CHKERRQ(ierr);
3366   ierr = PetscObjectStateIncrease((PetscObject)B);CHKERRQ(ierr);
3367   PetscFunctionReturn(0);
3368 }
3369 
3370 #undef __FUNCT__
3371 #define __FUNCT__ "MatConvert"
3372 /*@C
3373    MatConvert - Converts a matrix to another matrix, either of the same
3374    or different type.
3375 
3376    Collective on Mat
3377 
3378    Input Parameters:
3379 +  mat - the matrix
3380 .  newtype - new matrix type.  Use MATSAME to create a new matrix of the
3381    same type as the original matrix.
3382 -  reuse - denotes if the destination matrix is to be created or reused.  Currently
3383    MAT_REUSE_MATRIX is only supported for inplace conversion, otherwise use
3384    MAT_INITIAL_MATRIX.
3385 
3386    Output Parameter:
3387 .  M - pointer to place new matrix
3388 
3389    Notes:
3390    MatConvert() first creates a new matrix and then copies the data from
3391    the first matrix.  A related routine is MatCopy(), which copies the matrix
3392    entries of one matrix to another already existing matrix context.
3393 
3394    Cannot be used to convert a sequential matrix to parallel or parallel to sequential,
3395    the MPI communicator of the generated matrix is always the same as the communicator
3396    of the input matrix.
3397 
3398    Level: intermediate
3399 
3400    Concepts: matrices^converting between storage formats
3401 
3402 .seealso: MatCopy(), MatDuplicate()
3403 @*/
3404 PetscErrorCode PETSCMAT_DLLEXPORT MatConvert(Mat mat, const MatType newtype,MatReuse reuse,Mat *M)
3405 {
3406   PetscErrorCode         ierr;
3407   PetscTruth             sametype,issame,flg;
3408   char                   convname[256],mtype[256];
3409   Mat                    B;
3410 
3411   PetscFunctionBegin;
3412   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3413   PetscValidType(mat,1);
3414   PetscValidPointer(M,3);
3415   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3416   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3417   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3418 
3419   ierr = PetscOptionsGetString(((PetscObject)mat)->prefix,"-matconvert_type",mtype,256,&flg);CHKERRQ(ierr);
3420   if (flg) {
3421     newtype = mtype;
3422   }
3423   ierr = PetscTypeCompare((PetscObject)mat,newtype,&sametype);CHKERRQ(ierr);
3424   ierr = PetscStrcmp(newtype,"same",&issame);CHKERRQ(ierr);
3425   if ((reuse == MAT_REUSE_MATRIX) && (mat != *M)) {
3426     SETERRQ(PETSC_ERR_SUP,"MAT_REUSE_MATRIX only supported for in-place conversion currently");
3427   }
3428 
3429   if ((reuse == MAT_REUSE_MATRIX) && (issame || sametype)) PetscFunctionReturn(0);
3430 
3431   if ((sametype || issame) && (reuse==MAT_INITIAL_MATRIX) && mat->ops->duplicate) {
3432     ierr = (*mat->ops->duplicate)(mat,MAT_COPY_VALUES,M);CHKERRQ(ierr);
3433   } else {
3434     PetscErrorCode (*conv)(Mat, const MatType,MatReuse,Mat*)=PETSC_NULL;
3435     const char     *prefix[3] = {"seq","mpi",""};
3436     PetscInt       i;
3437     /*
3438        Order of precedence:
3439        1) See if a specialized converter is known to the current matrix.
3440        2) See if a specialized converter is known to the desired matrix class.
3441        3) See if a good general converter is registered for the desired class
3442           (as of 6/27/03 only MATMPIADJ falls into this category).
3443        4) See if a good general converter is known for the current matrix.
3444        5) Use a really basic converter.
3445     */
3446 
3447     /* 1) See if a specialized converter is known to the current matrix and the desired class */
3448     for (i=0; i<3; i++) {
3449       ierr = PetscStrcpy(convname,"MatConvert_");CHKERRQ(ierr);
3450       ierr = PetscStrcat(convname,((PetscObject)mat)->type_name);CHKERRQ(ierr);
3451       ierr = PetscStrcat(convname,"_");CHKERRQ(ierr);
3452       ierr = PetscStrcat(convname,prefix[i]);CHKERRQ(ierr);
3453       ierr = PetscStrcat(convname,newtype);CHKERRQ(ierr);
3454       ierr = PetscStrcat(convname,"_C");CHKERRQ(ierr);
3455       ierr = PetscObjectQueryFunction((PetscObject)mat,convname,(void (**)(void))&conv);CHKERRQ(ierr);
3456       if (conv) goto foundconv;
3457     }
3458 
3459     /* 2)  See if a specialized converter is known to the desired matrix class. */
3460     ierr = MatCreate(((PetscObject)mat)->comm,&B);CHKERRQ(ierr);
3461     ierr = MatSetSizes(B,mat->rmap->n,mat->cmap->n,mat->rmap->N,mat->cmap->N);CHKERRQ(ierr);
3462     ierr = MatSetType(B,newtype);CHKERRQ(ierr);
3463     for (i=0; i<3; i++) {
3464       ierr = PetscStrcpy(convname,"MatConvert_");CHKERRQ(ierr);
3465       ierr = PetscStrcat(convname,((PetscObject)mat)->type_name);CHKERRQ(ierr);
3466       ierr = PetscStrcat(convname,"_");CHKERRQ(ierr);
3467       ierr = PetscStrcat(convname,prefix[i]);CHKERRQ(ierr);
3468       ierr = PetscStrcat(convname,newtype);CHKERRQ(ierr);
3469       ierr = PetscStrcat(convname,"_C");CHKERRQ(ierr);
3470       ierr = PetscObjectQueryFunction((PetscObject)B,convname,(void (**)(void))&conv);CHKERRQ(ierr);
3471       if (conv) {
3472         ierr = MatDestroy(B);CHKERRQ(ierr);
3473         goto foundconv;
3474       }
3475     }
3476 
3477     /* 3) See if a good general converter is registered for the desired class */
3478     conv = B->ops->convertfrom;
3479     ierr = MatDestroy(B);CHKERRQ(ierr);
3480     if (conv) goto foundconv;
3481 
3482     /* 4) See if a good general converter is known for the current matrix */
3483     if (mat->ops->convert) {
3484       conv = mat->ops->convert;
3485     }
3486     if (conv) goto foundconv;
3487 
3488     /* 5) Use a really basic converter. */
3489     conv = MatConvert_Basic;
3490 
3491     foundconv:
3492     ierr = PetscLogEventBegin(MAT_Convert,mat,0,0,0);CHKERRQ(ierr);
3493     ierr = (*conv)(mat,newtype,reuse,M);CHKERRQ(ierr);
3494     ierr = PetscLogEventEnd(MAT_Convert,mat,0,0,0);CHKERRQ(ierr);
3495   }
3496   ierr = PetscObjectStateIncrease((PetscObject)*M);CHKERRQ(ierr);
3497   PetscFunctionReturn(0);
3498 }
3499 
3500 #undef __FUNCT__
3501 #define __FUNCT__ "MatFactorGetSolverPackage"
3502 /*@C
3503    MatFactorGetSolverPackage - Returns name of the package providing the factorization routines
3504 
3505    Not Collective
3506 
3507    Input Parameter:
3508 .  mat - the matrix, must be a factored matrix
3509 
3510    Output Parameter:
3511 .   type - the string name of the package (do not free this string)
3512 
3513    Notes:
3514       In Fortran you pass in a empty string and the package name will be copied into it.
3515     (Make sure the string is long enough)
3516 
3517    Level: intermediate
3518 
3519 .seealso: MatCopy(), MatDuplicate(), MatGetFactorAvailable(), MatGetFactor()
3520 @*/
3521 PetscErrorCode PETSCMAT_DLLEXPORT MatFactorGetSolverPackage(Mat mat, const MatSolverPackage *type)
3522 {
3523   PetscErrorCode         ierr;
3524   PetscErrorCode         (*conv)(Mat,const MatSolverPackage*);
3525 
3526   PetscFunctionBegin;
3527   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3528   PetscValidType(mat,1);
3529   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Only for factored matrix");
3530   ierr = PetscObjectQueryFunction((PetscObject)mat,"MatFactorGetSolverPackage_C",(void (**)(void))&conv);CHKERRQ(ierr);
3531   if (!conv) {
3532     *type = MAT_SOLVER_PETSC;
3533   } else {
3534     ierr = (*conv)(mat,type);CHKERRQ(ierr);
3535   }
3536   PetscFunctionReturn(0);
3537 }
3538 
3539 #undef __FUNCT__
3540 #define __FUNCT__ "MatGetFactor"
3541 /*@C
3542    MatGetFactor - Returns a matrix suitable to calls to MatXXFactorSymbolic()
3543 
3544    Collective on Mat
3545 
3546    Input Parameters:
3547 +  mat - the matrix
3548 .  type - name of solver type, for example, spooles, superlu, plapack, petsc (to use PETSc's default)
3549 -  ftype - factor type, MAT_FACTOR_LU, MAT_FACTOR_CHOLESKY, MAT_FACTOR_ICC, MAT_FACTOR_ILU,
3550 
3551    Output Parameters:
3552 .  f - the factor matrix used with MatXXFactorSymbolic() calls
3553 
3554    Notes:
3555       Some PETSc matrix formats have alternative solvers available that are contained in alternative packages
3556      such as pastix, superlu, mumps, spooles etc.
3557 
3558       PETSc must have been config/configure.py to use the external solver, using the option --download-package
3559 
3560    Level: intermediate
3561 
3562 .seealso: MatCopy(), MatDuplicate(), MatGetFactorAvailable()
3563 @*/
3564 PetscErrorCode PETSCMAT_DLLEXPORT MatGetFactor(Mat mat, const MatSolverPackage type,MatFactorType ftype,Mat *f)
3565 {
3566   PetscErrorCode         ierr;
3567   char                   convname[256];
3568   PetscErrorCode         (*conv)(Mat,MatFactorType,Mat*);
3569 
3570   PetscFunctionBegin;
3571   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3572   PetscValidType(mat,1);
3573 
3574   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3575   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3576 
3577   ierr = PetscStrcpy(convname,"MatGetFactor_");CHKERRQ(ierr);
3578   ierr = PetscStrcat(convname,((PetscObject)mat)->type_name);CHKERRQ(ierr);
3579   ierr = PetscStrcat(convname,"_");CHKERRQ(ierr);
3580   ierr = PetscStrcat(convname,type);CHKERRQ(ierr);
3581   ierr = PetscStrcat(convname,"_C");CHKERRQ(ierr);
3582   ierr = PetscObjectQueryFunction((PetscObject)mat,convname,(void (**)(void))&conv);CHKERRQ(ierr);
3583   if (!conv) {
3584     PetscTruth flag;
3585     ierr = PetscStrcasecmp(MAT_SOLVER_PETSC,type,&flag);CHKERRQ(ierr);
3586     if (flag) {
3587       SETERRQ1(PETSC_ERR_SUP,"Matrix format %s does not have a built-in PETSc direct solver",((PetscObject)mat)->type_name);
3588     } else {
3589       SETERRQ3(PETSC_ERR_SUP,"Matrix format %s does not have a solver %s. Perhaps you must config/configure.py with --download-%s",((PetscObject)mat)->type_name,type,type);
3590     }
3591   }
3592   ierr = (*conv)(mat,ftype,f);CHKERRQ(ierr);
3593   PetscFunctionReturn(0);
3594 }
3595 
3596 #undef __FUNCT__
3597 #define __FUNCT__ "MatGetFactorAvailable"
3598 /*@C
3599    MatGetFactorAvailable - Returns a a flag if matrix supports particular package and factor type
3600 
3601    Collective on Mat
3602 
3603    Input Parameters:
3604 +  mat - the matrix
3605 .  type - name of solver type, for example, spooles, superlu, plapack, petsc (to use PETSc's default)
3606 -  ftype - factor type, MAT_FACTOR_LU, MAT_FACTOR_CHOLESKY, MAT_FACTOR_ICC, MAT_FACTOR_ILU,
3607 
3608    Output Parameter:
3609 .    flg - PETSC_TRUE if the factorization is available
3610 
3611    Notes:
3612       Some PETSc matrix formats have alternative solvers available that are contained in alternative packages
3613      such as pastix, superlu, mumps, spooles etc.
3614 
3615       PETSc must have been config/configure.py to use the external solver, using the option --download-package
3616 
3617    Level: intermediate
3618 
3619 .seealso: MatCopy(), MatDuplicate(), MatGetFactor()
3620 @*/
3621 PetscErrorCode PETSCMAT_DLLEXPORT MatGetFactorAvailable(Mat mat, const MatSolverPackage type,MatFactorType ftype,PetscTruth *flg)
3622 {
3623   PetscErrorCode         ierr;
3624   char                   convname[256];
3625   PetscErrorCode         (*conv)(Mat,MatFactorType,PetscTruth*);
3626 
3627   PetscFunctionBegin;
3628   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3629   PetscValidType(mat,1);
3630 
3631   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3632   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3633 
3634   ierr = PetscStrcpy(convname,"MatGetFactorAvailable_");CHKERRQ(ierr);
3635   ierr = PetscStrcat(convname,((PetscObject)mat)->type_name);CHKERRQ(ierr);
3636   ierr = PetscStrcat(convname,"_");CHKERRQ(ierr);
3637   ierr = PetscStrcat(convname,type);CHKERRQ(ierr);
3638   ierr = PetscStrcat(convname,"_C");CHKERRQ(ierr);
3639   ierr = PetscObjectQueryFunction((PetscObject)mat,convname,(void (**)(void))&conv);CHKERRQ(ierr);
3640   if (!conv) {
3641     *flg = PETSC_FALSE;
3642   } else {
3643     ierr = (*conv)(mat,ftype,flg);CHKERRQ(ierr);
3644   }
3645   PetscFunctionReturn(0);
3646 }
3647 
3648 
3649 #undef __FUNCT__
3650 #define __FUNCT__ "MatDuplicate"
3651 /*@
3652    MatDuplicate - Duplicates a matrix including the non-zero structure.
3653 
3654    Collective on Mat
3655 
3656    Input Parameters:
3657 +  mat - the matrix
3658 -  op - either MAT_DO_NOT_COPY_VALUES or MAT_COPY_VALUES, cause it to copy nonzero
3659         values as well or not or MAT_SHARE_NONZERO_PATTERN
3660 
3661    Output Parameter:
3662 .  M - pointer to place new matrix
3663 
3664    Level: intermediate
3665 
3666    Concepts: matrices^duplicating
3667 
3668 .seealso: MatCopy(), MatConvert()
3669 @*/
3670 PetscErrorCode PETSCMAT_DLLEXPORT MatDuplicate(Mat mat,MatDuplicateOption op,Mat *M)
3671 {
3672   PetscErrorCode ierr;
3673   Mat            B;
3674   PetscInt       i;
3675 
3676   PetscFunctionBegin;
3677   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3678   PetscValidType(mat,1);
3679   PetscValidPointer(M,3);
3680   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3681   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3682   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3683 
3684   *M  = 0;
3685   if (!mat->ops->duplicate) {
3686     SETERRQ(PETSC_ERR_SUP,"Not written for this matrix type");
3687   }
3688   ierr = PetscLogEventBegin(MAT_Convert,mat,0,0,0);CHKERRQ(ierr);
3689   ierr = (*mat->ops->duplicate)(mat,op,M);CHKERRQ(ierr);
3690   B = *M;
3691   if (mat->mapping) {
3692     ierr = MatSetLocalToGlobalMapping(B,mat->mapping);CHKERRQ(ierr);
3693   }
3694   if (mat->bmapping) {
3695     ierr = MatSetLocalToGlobalMappingBlock(B,mat->bmapping);CHKERRQ(ierr);
3696   }
3697   ierr = PetscMapCopy(((PetscObject)mat)->comm,mat->rmap,B->rmap);CHKERRQ(ierr);
3698   ierr = PetscMapCopy(((PetscObject)mat)->comm,mat->cmap,B->cmap);CHKERRQ(ierr);
3699 
3700   B->stencil.dim = mat->stencil.dim;
3701   B->stencil.noc = mat->stencil.noc;
3702   for (i=0; i<=mat->stencil.dim; i++) {
3703     B->stencil.dims[i]   = mat->stencil.dims[i];
3704     B->stencil.starts[i] = mat->stencil.starts[i];
3705   }
3706 
3707   ierr = PetscLogEventEnd(MAT_Convert,mat,0,0,0);CHKERRQ(ierr);
3708   ierr = PetscObjectStateIncrease((PetscObject)B);CHKERRQ(ierr);
3709   PetscFunctionReturn(0);
3710 }
3711 
3712 #undef __FUNCT__
3713 #define __FUNCT__ "MatGetDiagonal"
3714 /*@
3715    MatGetDiagonal - Gets the diagonal of a matrix.
3716 
3717    Collective on Mat and Vec
3718 
3719    Input Parameters:
3720 +  mat - the matrix
3721 -  v - the vector for storing the diagonal
3722 
3723    Output Parameter:
3724 .  v - the diagonal of the matrix
3725 
3726    Level: intermediate
3727 
3728    Concepts: matrices^accessing diagonals
3729 
3730 .seealso: MatGetRow(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMaxAbs()
3731 @*/
3732 PetscErrorCode PETSCMAT_DLLEXPORT MatGetDiagonal(Mat mat,Vec v)
3733 {
3734   PetscErrorCode ierr;
3735 
3736   PetscFunctionBegin;
3737   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3738   PetscValidType(mat,1);
3739   PetscValidHeaderSpecific(v,VEC_COOKIE,2);
3740   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3741   if (!mat->ops->getdiagonal) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3742   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3743 
3744   ierr = (*mat->ops->getdiagonal)(mat,v);CHKERRQ(ierr);
3745   ierr = PetscObjectStateIncrease((PetscObject)v);CHKERRQ(ierr);
3746   PetscFunctionReturn(0);
3747 }
3748 
3749 #undef __FUNCT__
3750 #define __FUNCT__ "MatGetRowMin"
3751 /*@
3752    MatGetRowMin - Gets the minimum value (of the real part) of each
3753         row of the matrix
3754 
3755    Collective on Mat and Vec
3756 
3757    Input Parameters:
3758 .  mat - the matrix
3759 
3760    Output Parameter:
3761 +  v - the vector for storing the maximums
3762 -  idx - the indices of the column found for each row (optional)
3763 
3764    Level: intermediate
3765 
3766    Notes: The result of this call are the same as if one converted the matrix to dense format
3767       and found the minimum value in each row (i.e. the implicit zeros are counted as zeros).
3768 
3769     This code is only implemented for a couple of matrix formats.
3770 
3771    Concepts: matrices^getting row maximums
3772 
3773 .seealso: MatGetDiagonal(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMaxAbs(),
3774           MatGetRowMax()
3775 @*/
3776 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRowMin(Mat mat,Vec v,PetscInt idx[])
3777 {
3778   PetscErrorCode ierr;
3779 
3780   PetscFunctionBegin;
3781   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3782   PetscValidType(mat,1);
3783   PetscValidHeaderSpecific(v,VEC_COOKIE,2);
3784   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3785   if (!mat->ops->getrowmax) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3786   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3787 
3788   ierr = (*mat->ops->getrowmin)(mat,v,idx);CHKERRQ(ierr);
3789   ierr = PetscObjectStateIncrease((PetscObject)v);CHKERRQ(ierr);
3790   PetscFunctionReturn(0);
3791 }
3792 
3793 #undef __FUNCT__
3794 #define __FUNCT__ "MatGetRowMinAbs"
3795 /*@
3796    MatGetRowMinAbs - Gets the minimum value (in absolute value) of each
3797         row of the matrix
3798 
3799    Collective on Mat and Vec
3800 
3801    Input Parameters:
3802 .  mat - the matrix
3803 
3804    Output Parameter:
3805 +  v - the vector for storing the minimums
3806 -  idx - the indices of the column found for each row (optional)
3807 
3808    Level: intermediate
3809 
3810    Notes: if a row is completely empty or has only 0.0 values then the idx[] value for that
3811     row is 0 (the first column).
3812 
3813     This code is only implemented for a couple of matrix formats.
3814 
3815    Concepts: matrices^getting row maximums
3816 
3817 .seealso: MatGetDiagonal(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMax(), MatGetRowMaxAbs(), MatGetRowMin()
3818 @*/
3819 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRowMinAbs(Mat mat,Vec v,PetscInt idx[])
3820 {
3821   PetscErrorCode ierr;
3822 
3823   PetscFunctionBegin;
3824   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3825   PetscValidType(mat,1);
3826   PetscValidHeaderSpecific(v,VEC_COOKIE,2);
3827   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3828   if (!mat->ops->getrowminabs) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3829   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3830   if (idx) {ierr = PetscMemzero(idx,mat->rmap->n*sizeof(PetscInt));CHKERRQ(ierr);}
3831 
3832   ierr = (*mat->ops->getrowminabs)(mat,v,idx);CHKERRQ(ierr);
3833   ierr = PetscObjectStateIncrease((PetscObject)v);CHKERRQ(ierr);
3834   PetscFunctionReturn(0);
3835 }
3836 
3837 #undef __FUNCT__
3838 #define __FUNCT__ "MatGetRowMax"
3839 /*@
3840    MatGetRowMax - Gets the maximum value (of the real part) of each
3841         row of the matrix
3842 
3843    Collective on Mat and Vec
3844 
3845    Input Parameters:
3846 .  mat - the matrix
3847 
3848    Output Parameter:
3849 +  v - the vector for storing the maximums
3850 -  idx - the indices of the column found for each row (optional)
3851 
3852    Level: intermediate
3853 
3854    Notes: The result of this call are the same as if one converted the matrix to dense format
3855       and found the minimum value in each row (i.e. the implicit zeros are counted as zeros).
3856 
3857     This code is only implemented for a couple of matrix formats.
3858 
3859    Concepts: matrices^getting row maximums
3860 
3861 .seealso: MatGetDiagonal(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMaxAbs(), MatGetRowMin()
3862 @*/
3863 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRowMax(Mat mat,Vec v,PetscInt idx[])
3864 {
3865   PetscErrorCode ierr;
3866 
3867   PetscFunctionBegin;
3868   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3869   PetscValidType(mat,1);
3870   PetscValidHeaderSpecific(v,VEC_COOKIE,2);
3871   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3872   if (!mat->ops->getrowmax) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3873   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3874 
3875   ierr = (*mat->ops->getrowmax)(mat,v,idx);CHKERRQ(ierr);
3876   ierr = PetscObjectStateIncrease((PetscObject)v);CHKERRQ(ierr);
3877   PetscFunctionReturn(0);
3878 }
3879 
3880 #undef __FUNCT__
3881 #define __FUNCT__ "MatGetRowMaxAbs"
3882 /*@
3883    MatGetRowMaxAbs - Gets the maximum value (in absolute value) of each
3884         row of the matrix
3885 
3886    Collective on Mat and Vec
3887 
3888    Input Parameters:
3889 .  mat - the matrix
3890 
3891    Output Parameter:
3892 +  v - the vector for storing the maximums
3893 -  idx - the indices of the column found for each row (optional)
3894 
3895    Level: intermediate
3896 
3897    Notes: if a row is completely empty or has only 0.0 values then the idx[] value for that
3898     row is 0 (the first column).
3899 
3900     This code is only implemented for a couple of matrix formats.
3901 
3902    Concepts: matrices^getting row maximums
3903 
3904 .seealso: MatGetDiagonal(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMax(), MatGetRowMin()
3905 @*/
3906 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRowMaxAbs(Mat mat,Vec v,PetscInt idx[])
3907 {
3908   PetscErrorCode ierr;
3909 
3910   PetscFunctionBegin;
3911   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3912   PetscValidType(mat,1);
3913   PetscValidHeaderSpecific(v,VEC_COOKIE,2);
3914   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3915   if (!mat->ops->getrowmaxabs) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3916   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3917   if (idx) {ierr = PetscMemzero(idx,mat->rmap->n*sizeof(PetscInt));CHKERRQ(ierr);}
3918 
3919   ierr = (*mat->ops->getrowmaxabs)(mat,v,idx);CHKERRQ(ierr);
3920   ierr = PetscObjectStateIncrease((PetscObject)v);CHKERRQ(ierr);
3921   PetscFunctionReturn(0);
3922 }
3923 
3924 #undef __FUNCT__
3925 #define __FUNCT__ "MatGetRowSum"
3926 /*@
3927    MatGetRowSum - Gets the sum of each row of the matrix
3928 
3929    Collective on Mat and Vec
3930 
3931    Input Parameters:
3932 .  mat - the matrix
3933 
3934    Output Parameter:
3935 .  v - the vector for storing the maximums
3936 
3937    Level: intermediate
3938 
3939    Notes: This code is slow since it is not currently specialized for different formats
3940 
3941    Concepts: matrices^getting row sums
3942 
3943 .seealso: MatGetDiagonal(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMax(), MatGetRowMin()
3944 @*/
3945 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRowSum(Mat mat, Vec v)
3946 {
3947   PetscInt       start, end, row;
3948   PetscScalar   *array;
3949   PetscErrorCode ierr;
3950 
3951   PetscFunctionBegin;
3952   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3953   PetscValidType(mat,1);
3954   PetscValidHeaderSpecific(v,VEC_COOKIE,2);
3955   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3956   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3957   ierr = MatGetOwnershipRange(mat, &start, &end);CHKERRQ(ierr);
3958   ierr = VecGetArray(v, &array);CHKERRQ(ierr);
3959   for(row = start; row < end; ++row) {
3960     PetscInt           ncols, col;
3961     const PetscInt    *cols;
3962     const PetscScalar *vals;
3963 
3964     array[row - start] = 0.0;
3965     ierr = MatGetRow(mat, row, &ncols, &cols, &vals);CHKERRQ(ierr);
3966     for(col = 0; col < ncols; col++) {
3967       array[row - start] += vals[col];
3968     }
3969     ierr = MatRestoreRow(mat, row, &ncols, &cols, &vals);CHKERRQ(ierr);
3970   }
3971   ierr = VecRestoreArray(v, &array);CHKERRQ(ierr);
3972   ierr = PetscObjectStateIncrease((PetscObject) v);CHKERRQ(ierr);
3973   PetscFunctionReturn(0);
3974 }
3975 
3976 #undef __FUNCT__
3977 #define __FUNCT__ "MatTranspose"
3978 /*@
3979    MatTranspose - Computes an in-place or out-of-place transpose of a matrix.
3980 
3981    Collective on Mat
3982 
3983    Input Parameter:
3984 +  mat - the matrix to transpose
3985 -  reuse - store the transpose matrix in the provided B
3986 
3987    Output Parameters:
3988 .  B - the transpose
3989 
3990    Notes:
3991      If you  pass in &mat for B the transpose will be done in place
3992 
3993    Level: intermediate
3994 
3995    Concepts: matrices^transposing
3996 
3997 .seealso: MatMultTranspose(), MatMultTransposeAdd(), MatIsTranspose()
3998 @*/
3999 PetscErrorCode PETSCMAT_DLLEXPORT MatTranspose(Mat mat,MatReuse reuse,Mat *B)
4000 {
4001   PetscErrorCode ierr;
4002 
4003   PetscFunctionBegin;
4004   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4005   PetscValidType(mat,1);
4006   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4007   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4008   if (!mat->ops->transpose) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
4009   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4010 
4011   ierr = PetscLogEventBegin(MAT_Transpose,mat,0,0,0);CHKERRQ(ierr);
4012   ierr = (*mat->ops->transpose)(mat,reuse,B);CHKERRQ(ierr);
4013   ierr = PetscLogEventEnd(MAT_Transpose,mat,0,0,0);CHKERRQ(ierr);
4014   if (B) {ierr = PetscObjectStateIncrease((PetscObject)*B);CHKERRQ(ierr);}
4015   PetscFunctionReturn(0);
4016 }
4017 
4018 #undef __FUNCT__
4019 #define __FUNCT__ "MatIsTranspose"
4020 /*@
4021    MatIsTranspose - Test whether a matrix is another one's transpose,
4022         or its own, in which case it tests symmetry.
4023 
4024    Collective on Mat
4025 
4026    Input Parameter:
4027 +  A - the matrix to test
4028 -  B - the matrix to test against, this can equal the first parameter
4029 
4030    Output Parameters:
4031 .  flg - the result
4032 
4033    Notes:
4034    Only available for SeqAIJ/MPIAIJ matrices. The sequential algorithm
4035    has a running time of the order of the number of nonzeros; the parallel
4036    test involves parallel copies of the block-offdiagonal parts of the matrix.
4037 
4038    Level: intermediate
4039 
4040    Concepts: matrices^transposing, matrix^symmetry
4041 
4042 .seealso: MatTranspose(), MatIsSymmetric(), MatIsHermitian()
4043 @*/
4044 PetscErrorCode PETSCMAT_DLLEXPORT MatIsTranspose(Mat A,Mat B,PetscReal tol,PetscTruth *flg)
4045 {
4046   PetscErrorCode ierr,(*f)(Mat,Mat,PetscReal,PetscTruth*),(*g)(Mat,Mat,PetscReal,PetscTruth*);
4047 
4048   PetscFunctionBegin;
4049   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
4050   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
4051   PetscValidPointer(flg,3);
4052   ierr = PetscObjectQueryFunction((PetscObject)A,"MatIsTranspose_C",(void (**)(void))&f);CHKERRQ(ierr);
4053   ierr = PetscObjectQueryFunction((PetscObject)B,"MatIsTranspose_C",(void (**)(void))&g);CHKERRQ(ierr);
4054   if (f && g) {
4055     if (f==g) {
4056       ierr = (*f)(A,B,tol,flg);CHKERRQ(ierr);
4057     } else {
4058       SETERRQ(PETSC_ERR_ARG_NOTSAMETYPE,"Matrices do not have the same comparator for symmetry test");
4059     }
4060   }
4061   PetscFunctionReturn(0);
4062 }
4063 
4064 #undef __FUNCT__
4065 #define __FUNCT__ "MatIsHermitianTranspose"
4066 /*@
4067    MatIsHermitianTranspose - Test whether a matrix is another one's Hermitian transpose,
4068 
4069    Collective on Mat
4070 
4071    Input Parameter:
4072 +  A - the matrix to test
4073 -  B - the matrix to test against, this can equal the first parameter
4074 
4075    Output Parameters:
4076 .  flg - the result
4077 
4078    Notes:
4079    Only available for SeqAIJ/MPIAIJ matrices. The sequential algorithm
4080    has a running time of the order of the number of nonzeros; the parallel
4081    test involves parallel copies of the block-offdiagonal parts of the matrix.
4082 
4083    Level: intermediate
4084 
4085    Concepts: matrices^transposing, matrix^symmetry
4086 
4087 .seealso: MatTranspose(), MatIsSymmetric(), MatIsHermitian(), MatIsTranspose()
4088 @*/
4089 PetscErrorCode PETSCMAT_DLLEXPORT MatIsHermitianTranspose(Mat A,Mat B,PetscReal tol,PetscTruth *flg)
4090 {
4091   PetscErrorCode ierr,(*f)(Mat,Mat,PetscReal,PetscTruth*),(*g)(Mat,Mat,PetscReal,PetscTruth*);
4092 
4093   PetscFunctionBegin;
4094   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
4095   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
4096   PetscValidPointer(flg,3);
4097   ierr = PetscObjectQueryFunction((PetscObject)A,"MatIsHermitianTranspose_C",(void (**)(void))&f);CHKERRQ(ierr);
4098   ierr = PetscObjectQueryFunction((PetscObject)B,"MatIsHermitianTranspose_C",(void (**)(void))&g);CHKERRQ(ierr);
4099   if (f && g) {
4100     if (f==g) {
4101       ierr = (*f)(A,B,tol,flg);CHKERRQ(ierr);
4102     } else {
4103       SETERRQ(PETSC_ERR_ARG_NOTSAMETYPE,"Matrices do not have the same comparator for Hermitian test");
4104     }
4105   }
4106   PetscFunctionReturn(0);
4107 }
4108 
4109 #undef __FUNCT__
4110 #define __FUNCT__ "MatPermute"
4111 /*@
4112    MatPermute - Creates a new matrix with rows and columns permuted from the
4113    original.
4114 
4115    Collective on Mat
4116 
4117    Input Parameters:
4118 +  mat - the matrix to permute
4119 .  row - row permutation, each processor supplies only the permutation for its rows
4120 -  col - column permutation, each processor needs the entire column permutation, that is
4121          this is the same size as the total number of columns in the matrix. It can often
4122          be obtained with ISAllGather() on the row permutation
4123 
4124    Output Parameters:
4125 .  B - the permuted matrix
4126 
4127    Level: advanced
4128 
4129    Concepts: matrices^permuting
4130 
4131 .seealso: MatGetOrdering(), ISAllGather()
4132 
4133 @*/
4134 PetscErrorCode PETSCMAT_DLLEXPORT MatPermute(Mat mat,IS row,IS col,Mat *B)
4135 {
4136   PetscErrorCode ierr;
4137 
4138   PetscFunctionBegin;
4139   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4140   PetscValidType(mat,1);
4141   PetscValidHeaderSpecific(row,IS_COOKIE,2);
4142   PetscValidHeaderSpecific(col,IS_COOKIE,3);
4143   PetscValidPointer(B,4);
4144   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4145   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4146   if (!mat->ops->permute) SETERRQ1(PETSC_ERR_SUP,"MatPermute not available for Mat type %s",((PetscObject)mat)->type_name);
4147   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4148 
4149   ierr = (*mat->ops->permute)(mat,row,col,B);CHKERRQ(ierr);
4150   ierr = PetscObjectStateIncrease((PetscObject)*B);CHKERRQ(ierr);
4151   PetscFunctionReturn(0);
4152 }
4153 
4154 #undef __FUNCT__
4155 #define __FUNCT__ "MatPermuteSparsify"
4156 /*@
4157   MatPermuteSparsify - Creates a new matrix with rows and columns permuted from the
4158   original and sparsified to the prescribed tolerance.
4159 
4160   Collective on Mat
4161 
4162   Input Parameters:
4163 + A    - The matrix to permute
4164 . band - The half-bandwidth of the sparsified matrix, or PETSC_DECIDE
4165 . frac - The half-bandwidth as a fraction of the total size, or 0.0
4166 . tol  - The drop tolerance
4167 . rowp - The row permutation
4168 - colp - The column permutation
4169 
4170   Output Parameter:
4171 . B    - The permuted, sparsified matrix
4172 
4173   Level: advanced
4174 
4175   Note:
4176   The default behavior (band = PETSC_DECIDE and frac = 0.0) is to
4177   restrict the half-bandwidth of the resulting matrix to 5% of the
4178   total matrix size.
4179 
4180 .keywords: matrix, permute, sparsify
4181 
4182 .seealso: MatGetOrdering(), MatPermute()
4183 @*/
4184 PetscErrorCode PETSCMAT_DLLEXPORT MatPermuteSparsify(Mat A, PetscInt band, PetscReal frac, PetscReal tol, IS rowp, IS colp, Mat *B)
4185 {
4186   IS                irowp, icolp;
4187   const PetscInt    *rows, *cols;
4188   PetscInt          M, N, locRowStart, locRowEnd;
4189   PetscInt          nz, newNz;
4190   const PetscInt    *cwork;
4191   PetscInt          *cnew;
4192   const PetscScalar *vwork;
4193   PetscScalar       *vnew;
4194   PetscInt          bw, issize;
4195   PetscInt          row, locRow, newRow, col, newCol;
4196   PetscErrorCode    ierr;
4197 
4198   PetscFunctionBegin;
4199   PetscValidHeaderSpecific(A,    MAT_COOKIE,1);
4200   PetscValidHeaderSpecific(rowp, IS_COOKIE,5);
4201   PetscValidHeaderSpecific(colp, IS_COOKIE,6);
4202   PetscValidPointer(B,7);
4203   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE, "Not for unassembled matrix");
4204   if (A->factor)     SETERRQ(PETSC_ERR_ARG_WRONGSTATE, "Not for factored matrix");
4205   if (!A->ops->permutesparsify) {
4206     ierr = MatGetSize(A, &M, &N);CHKERRQ(ierr);
4207     ierr = MatGetOwnershipRange(A, &locRowStart, &locRowEnd);CHKERRQ(ierr);
4208     ierr = ISGetSize(rowp, &issize);CHKERRQ(ierr);
4209     if (issize != M) SETERRQ2(PETSC_ERR_ARG_WRONG, "Wrong size %D for row permutation, should be %D", issize, M);
4210     ierr = ISGetSize(colp, &issize);CHKERRQ(ierr);
4211     if (issize != N) SETERRQ2(PETSC_ERR_ARG_WRONG, "Wrong size %D for column permutation, should be %D", issize, N);
4212     ierr = ISInvertPermutation(rowp, 0, &irowp);CHKERRQ(ierr);
4213     ierr = ISGetIndices(irowp, &rows);CHKERRQ(ierr);
4214     ierr = ISInvertPermutation(colp, 0, &icolp);CHKERRQ(ierr);
4215     ierr = ISGetIndices(icolp, &cols);CHKERRQ(ierr);
4216     ierr = PetscMalloc(N * sizeof(PetscInt),         &cnew);CHKERRQ(ierr);
4217     ierr = PetscMalloc(N * sizeof(PetscScalar), &vnew);CHKERRQ(ierr);
4218 
4219     /* Setup bandwidth to include */
4220     if (band == PETSC_DECIDE) {
4221       if (frac <= 0.0)
4222         bw = (PetscInt) (M * 0.05);
4223       else
4224         bw = (PetscInt) (M * frac);
4225     } else {
4226       if (band <= 0) SETERRQ(PETSC_ERR_ARG_WRONG, "Bandwidth must be a positive integer");
4227       bw = band;
4228     }
4229 
4230     /* Put values into new matrix */
4231     ierr = MatDuplicate(A, MAT_DO_NOT_COPY_VALUES, B);CHKERRQ(ierr);
4232     for(row = locRowStart, locRow = 0; row < locRowEnd; row++, locRow++) {
4233       ierr = MatGetRow(A, row, &nz, &cwork, &vwork);CHKERRQ(ierr);
4234       newRow   = rows[locRow]+locRowStart;
4235       for(col = 0, newNz = 0; col < nz; col++) {
4236         newCol = cols[cwork[col]];
4237         if ((newCol >= newRow - bw) && (newCol < newRow + bw) && (PetscAbsScalar(vwork[col]) >= tol)) {
4238           cnew[newNz] = newCol;
4239           vnew[newNz] = vwork[col];
4240           newNz++;
4241         }
4242       }
4243       ierr = MatSetValues(*B, 1, &newRow, newNz, cnew, vnew, INSERT_VALUES);CHKERRQ(ierr);
4244       ierr = MatRestoreRow(A, row, &nz, &cwork, &vwork);CHKERRQ(ierr);
4245     }
4246     ierr = PetscFree(cnew);CHKERRQ(ierr);
4247     ierr = PetscFree(vnew);CHKERRQ(ierr);
4248     ierr = MatAssemblyBegin(*B, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4249     ierr = MatAssemblyEnd(*B, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4250     ierr = ISRestoreIndices(irowp, &rows);CHKERRQ(ierr);
4251     ierr = ISRestoreIndices(icolp, &cols);CHKERRQ(ierr);
4252     ierr = ISDestroy(irowp);CHKERRQ(ierr);
4253     ierr = ISDestroy(icolp);CHKERRQ(ierr);
4254   } else {
4255     ierr = (*A->ops->permutesparsify)(A, band, frac, tol, rowp, colp, B);CHKERRQ(ierr);
4256   }
4257   ierr = PetscObjectStateIncrease((PetscObject)*B);CHKERRQ(ierr);
4258   PetscFunctionReturn(0);
4259 }
4260 
4261 #undef __FUNCT__
4262 #define __FUNCT__ "MatEqual"
4263 /*@
4264    MatEqual - Compares two matrices.
4265 
4266    Collective on Mat
4267 
4268    Input Parameters:
4269 +  A - the first matrix
4270 -  B - the second matrix
4271 
4272    Output Parameter:
4273 .  flg - PETSC_TRUE if the matrices are equal; PETSC_FALSE otherwise.
4274 
4275    Level: intermediate
4276 
4277    Concepts: matrices^equality between
4278 @*/
4279 PetscErrorCode PETSCMAT_DLLEXPORT MatEqual(Mat A,Mat B,PetscTruth *flg)
4280 {
4281   PetscErrorCode ierr;
4282 
4283   PetscFunctionBegin;
4284   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
4285   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
4286   PetscValidType(A,1);
4287   PetscValidType(B,2);
4288   PetscValidIntPointer(flg,3);
4289   PetscCheckSameComm(A,1,B,2);
4290   ierr = MatPreallocated(B);CHKERRQ(ierr);
4291   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4292   if (!B->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4293   if (A->rmap->N != B->rmap->N || A->cmap->N != B->cmap->N) SETERRQ4(PETSC_ERR_ARG_SIZ,"Mat A,Mat B: global dim %D %D %D %D",A->rmap->N,B->rmap->N,A->cmap->N,B->cmap->N);
4294   if (!A->ops->equal) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)A)->type_name);
4295   if (!B->ops->equal) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)B)->type_name);
4296   if (A->ops->equal != B->ops->equal) SETERRQ2(PETSC_ERR_ARG_INCOMP,"A is type: %s\nB is type: %s",((PetscObject)A)->type_name,((PetscObject)B)->type_name);
4297   ierr = MatPreallocated(A);CHKERRQ(ierr);
4298 
4299   ierr = (*A->ops->equal)(A,B,flg);CHKERRQ(ierr);
4300   PetscFunctionReturn(0);
4301 }
4302 
4303 #undef __FUNCT__
4304 #define __FUNCT__ "MatDiagonalScale"
4305 /*@
4306    MatDiagonalScale - Scales a matrix on the left and right by diagonal
4307    matrices that are stored as vectors.  Either of the two scaling
4308    matrices can be PETSC_NULL.
4309 
4310    Collective on Mat
4311 
4312    Input Parameters:
4313 +  mat - the matrix to be scaled
4314 .  l - the left scaling vector (or PETSC_NULL)
4315 -  r - the right scaling vector (or PETSC_NULL)
4316 
4317    Notes:
4318    MatDiagonalScale() computes A = LAR, where
4319    L = a diagonal matrix (stored as a vector), R = a diagonal matrix (stored as a vector)
4320 
4321    Level: intermediate
4322 
4323    Concepts: matrices^diagonal scaling
4324    Concepts: diagonal scaling of matrices
4325 
4326 .seealso: MatScale()
4327 @*/
4328 PetscErrorCode PETSCMAT_DLLEXPORT MatDiagonalScale(Mat mat,Vec l,Vec r)
4329 {
4330   PetscErrorCode ierr;
4331 
4332   PetscFunctionBegin;
4333   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4334   PetscValidType(mat,1);
4335   if (!mat->ops->diagonalscale) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
4336   if (l) {PetscValidHeaderSpecific(l,VEC_COOKIE,2);PetscCheckSameComm(mat,1,l,2);}
4337   if (r) {PetscValidHeaderSpecific(r,VEC_COOKIE,3);PetscCheckSameComm(mat,1,r,3);}
4338   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4339   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4340   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4341 
4342   ierr = PetscLogEventBegin(MAT_Scale,mat,0,0,0);CHKERRQ(ierr);
4343   ierr = (*mat->ops->diagonalscale)(mat,l,r);CHKERRQ(ierr);
4344   ierr = PetscLogEventEnd(MAT_Scale,mat,0,0,0);CHKERRQ(ierr);
4345   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
4346   PetscFunctionReturn(0);
4347 }
4348 
4349 #undef __FUNCT__
4350 #define __FUNCT__ "MatScale"
4351 /*@
4352     MatScale - Scales all elements of a matrix by a given number.
4353 
4354     Collective on Mat
4355 
4356     Input Parameters:
4357 +   mat - the matrix to be scaled
4358 -   a  - the scaling value
4359 
4360     Output Parameter:
4361 .   mat - the scaled matrix
4362 
4363     Level: intermediate
4364 
4365     Concepts: matrices^scaling all entries
4366 
4367 .seealso: MatDiagonalScale()
4368 @*/
4369 PetscErrorCode PETSCMAT_DLLEXPORT MatScale(Mat mat,PetscScalar a)
4370 {
4371   PetscErrorCode ierr;
4372 
4373   PetscFunctionBegin;
4374   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4375   PetscValidType(mat,1);
4376   if (a != 1.0 && !mat->ops->scale) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
4377   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4378   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4379   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4380 
4381   ierr = PetscLogEventBegin(MAT_Scale,mat,0,0,0);CHKERRQ(ierr);
4382   if (a != 1.0) {
4383     ierr = (*mat->ops->scale)(mat,a);CHKERRQ(ierr);
4384     ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
4385   }
4386   ierr = PetscLogEventEnd(MAT_Scale,mat,0,0,0);CHKERRQ(ierr);
4387   PetscFunctionReturn(0);
4388 }
4389 
4390 #undef __FUNCT__
4391 #define __FUNCT__ "MatNorm"
4392 /*@
4393    MatNorm - Calculates various norms of a matrix.
4394 
4395    Collective on Mat
4396 
4397    Input Parameters:
4398 +  mat - the matrix
4399 -  type - the type of norm, NORM_1, NORM_FROBENIUS, NORM_INFINITY
4400 
4401    Output Parameters:
4402 .  nrm - the resulting norm
4403 
4404    Level: intermediate
4405 
4406    Concepts: matrices^norm
4407    Concepts: norm^of matrix
4408 @*/
4409 PetscErrorCode PETSCMAT_DLLEXPORT MatNorm(Mat mat,NormType type,PetscReal *nrm)
4410 {
4411   PetscErrorCode ierr;
4412 
4413   PetscFunctionBegin;
4414   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4415   PetscValidType(mat,1);
4416   PetscValidScalarPointer(nrm,3);
4417 
4418   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4419   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4420   if (!mat->ops->norm) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
4421   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4422 
4423   ierr = (*mat->ops->norm)(mat,type,nrm);CHKERRQ(ierr);
4424   PetscFunctionReturn(0);
4425 }
4426 
4427 /*
4428      This variable is used to prevent counting of MatAssemblyBegin() that
4429    are called from within a MatAssemblyEnd().
4430 */
4431 static PetscInt MatAssemblyEnd_InUse = 0;
4432 #undef __FUNCT__
4433 #define __FUNCT__ "MatAssemblyBegin"
4434 /*@
4435    MatAssemblyBegin - Begins assembling the matrix.  This routine should
4436    be called after completing all calls to MatSetValues().
4437 
4438    Collective on Mat
4439 
4440    Input Parameters:
4441 +  mat - the matrix
4442 -  type - type of assembly, either MAT_FLUSH_ASSEMBLY or MAT_FINAL_ASSEMBLY
4443 
4444    Notes:
4445    MatSetValues() generally caches the values.  The matrix is ready to
4446    use only after MatAssemblyBegin() and MatAssemblyEnd() have been called.
4447    Use MAT_FLUSH_ASSEMBLY when switching between ADD_VALUES and INSERT_VALUES
4448    in MatSetValues(); use MAT_FINAL_ASSEMBLY for the final assembly before
4449    using the matrix.
4450 
4451    Level: beginner
4452 
4453    Concepts: matrices^assembling
4454 
4455 .seealso: MatAssemblyEnd(), MatSetValues(), MatAssembled()
4456 @*/
4457 PetscErrorCode PETSCMAT_DLLEXPORT MatAssemblyBegin(Mat mat,MatAssemblyType type)
4458 {
4459   PetscErrorCode ierr;
4460 
4461   PetscFunctionBegin;
4462   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4463   PetscValidType(mat,1);
4464   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4465   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix.\nDid you forget to call MatSetUnfactored()?");
4466   if (mat->assembled) {
4467     mat->was_assembled = PETSC_TRUE;
4468     mat->assembled     = PETSC_FALSE;
4469   }
4470   if (!MatAssemblyEnd_InUse) {
4471     ierr = PetscLogEventBegin(MAT_AssemblyBegin,mat,0,0,0);CHKERRQ(ierr);
4472     if (mat->ops->assemblybegin){ierr = (*mat->ops->assemblybegin)(mat,type);CHKERRQ(ierr);}
4473     ierr = PetscLogEventEnd(MAT_AssemblyBegin,mat,0,0,0);CHKERRQ(ierr);
4474   } else {
4475     if (mat->ops->assemblybegin){ierr = (*mat->ops->assemblybegin)(mat,type);CHKERRQ(ierr);}
4476   }
4477   PetscFunctionReturn(0);
4478 }
4479 
4480 #undef __FUNCT__
4481 #define __FUNCT__ "MatAssembed"
4482 /*@
4483    MatAssembled - Indicates if a matrix has been assembled and is ready for
4484      use; for example, in matrix-vector product.
4485 
4486    Collective on Mat
4487 
4488    Input Parameter:
4489 .  mat - the matrix
4490 
4491    Output Parameter:
4492 .  assembled - PETSC_TRUE or PETSC_FALSE
4493 
4494    Level: advanced
4495 
4496    Concepts: matrices^assembled?
4497 
4498 .seealso: MatAssemblyEnd(), MatSetValues(), MatAssemblyBegin()
4499 @*/
4500 PetscErrorCode PETSCMAT_DLLEXPORT MatAssembled(Mat mat,PetscTruth *assembled)
4501 {
4502   PetscFunctionBegin;
4503   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4504   PetscValidType(mat,1);
4505   PetscValidPointer(assembled,2);
4506   *assembled = mat->assembled;
4507   PetscFunctionReturn(0);
4508 }
4509 
4510 #undef __FUNCT__
4511 #define __FUNCT__ "MatView_Private"
4512 /*
4513     Processes command line options to determine if/how a matrix
4514   is to be viewed. Called by MatAssemblyEnd() and MatLoad().
4515 */
4516 PetscErrorCode MatView_Private(Mat mat)
4517 {
4518   PetscErrorCode    ierr;
4519   PetscTruth        flg1 = PETSC_FALSE,flg2 = PETSC_FALSE,flg3 = PETSC_FALSE,flg4 = PETSC_FALSE,flg6 = PETSC_FALSE,flg7 = PETSC_FALSE,flg8 = PETSC_FALSE;
4520   static PetscTruth incall = PETSC_FALSE;
4521 #if defined(PETSC_USE_SOCKET_VIEWER)
4522   PetscTruth        flg5 = PETSC_FALSE;
4523 #endif
4524 
4525   PetscFunctionBegin;
4526   if (incall) PetscFunctionReturn(0);
4527   incall = PETSC_TRUE;
4528   ierr = PetscOptionsBegin(((PetscObject)mat)->comm,((PetscObject)mat)->prefix,"Matrix Options","Mat");CHKERRQ(ierr);
4529     ierr = PetscOptionsTruth("-mat_view_info","Information on matrix size","MatView",flg1,&flg1,PETSC_NULL);CHKERRQ(ierr);
4530     ierr = PetscOptionsTruth("-mat_view_info_detailed","Nonzeros in the matrix","MatView",flg2,&flg2,PETSC_NULL);CHKERRQ(ierr);
4531     ierr = PetscOptionsTruth("-mat_view","Print matrix to stdout","MatView",flg3,&flg3,PETSC_NULL);CHKERRQ(ierr);
4532     ierr = PetscOptionsTruth("-mat_view_matlab","Print matrix to stdout in a format Matlab can read","MatView",flg4,&flg4,PETSC_NULL);CHKERRQ(ierr);
4533 #if defined(PETSC_USE_SOCKET_VIEWER)
4534     ierr = PetscOptionsTruth("-mat_view_socket","Send matrix to socket (can be read from matlab)","MatView",flg5,&flg5,PETSC_NULL);CHKERRQ(ierr);
4535 #endif
4536     ierr = PetscOptionsTruth("-mat_view_binary","Save matrix to file in binary format","MatView",flg6,&flg6,PETSC_NULL);CHKERRQ(ierr);
4537     ierr = PetscOptionsTruth("-mat_view_draw","Draw the matrix nonzero structure","MatView",flg7,&flg7,PETSC_NULL);CHKERRQ(ierr);
4538   ierr = PetscOptionsEnd();CHKERRQ(ierr);
4539 
4540   if (flg1) {
4541     PetscViewer viewer;
4542 
4543     ierr = PetscViewerASCIIGetStdout(((PetscObject)mat)->comm,&viewer);CHKERRQ(ierr);
4544     ierr = PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_INFO);CHKERRQ(ierr);
4545     ierr = MatView(mat,viewer);CHKERRQ(ierr);
4546     ierr = PetscViewerPopFormat(viewer);CHKERRQ(ierr);
4547   }
4548   if (flg2) {
4549     PetscViewer viewer;
4550 
4551     ierr = PetscViewerASCIIGetStdout(((PetscObject)mat)->comm,&viewer);CHKERRQ(ierr);
4552     ierr = PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_INFO_DETAIL);CHKERRQ(ierr);
4553     ierr = MatView(mat,viewer);CHKERRQ(ierr);
4554     ierr = PetscViewerPopFormat(viewer);CHKERRQ(ierr);
4555   }
4556   if (flg3) {
4557     PetscViewer viewer;
4558 
4559     ierr = PetscViewerASCIIGetStdout(((PetscObject)mat)->comm,&viewer);CHKERRQ(ierr);
4560     ierr = MatView(mat,viewer);CHKERRQ(ierr);
4561   }
4562   if (flg4) {
4563     PetscViewer viewer;
4564 
4565     ierr = PetscViewerASCIIGetStdout(((PetscObject)mat)->comm,&viewer);CHKERRQ(ierr);
4566     ierr = PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_MATLAB);CHKERRQ(ierr);
4567     ierr = MatView(mat,viewer);CHKERRQ(ierr);
4568     ierr = PetscViewerPopFormat(viewer);CHKERRQ(ierr);
4569   }
4570 #if defined(PETSC_USE_SOCKET_VIEWER)
4571   if (flg5) {
4572     ierr = MatView(mat,PETSC_VIEWER_SOCKET_(((PetscObject)mat)->comm));CHKERRQ(ierr);
4573     ierr = PetscViewerFlush(PETSC_VIEWER_SOCKET_(((PetscObject)mat)->comm));CHKERRQ(ierr);
4574   }
4575 #endif
4576   if (flg6) {
4577     ierr = MatView(mat,PETSC_VIEWER_BINARY_(((PetscObject)mat)->comm));CHKERRQ(ierr);
4578     ierr = PetscViewerFlush(PETSC_VIEWER_BINARY_(((PetscObject)mat)->comm));CHKERRQ(ierr);
4579   }
4580   if (flg7) {
4581     ierr = PetscOptionsGetTruth(((PetscObject)mat)->prefix,"-mat_view_contour",&flg8,PETSC_NULL);CHKERRQ(ierr);
4582     if (flg8) {
4583       PetscViewerPushFormat(PETSC_VIEWER_DRAW_(((PetscObject)mat)->comm),PETSC_VIEWER_DRAW_CONTOUR);CHKERRQ(ierr);
4584     }
4585     ierr = MatView(mat,PETSC_VIEWER_DRAW_(((PetscObject)mat)->comm));CHKERRQ(ierr);
4586     ierr = PetscViewerFlush(PETSC_VIEWER_DRAW_(((PetscObject)mat)->comm));CHKERRQ(ierr);
4587     if (flg8) {
4588       PetscViewerPopFormat(PETSC_VIEWER_DRAW_(((PetscObject)mat)->comm));CHKERRQ(ierr);
4589     }
4590   }
4591   incall = PETSC_FALSE;
4592   PetscFunctionReturn(0);
4593 }
4594 
4595 #undef __FUNCT__
4596 #define __FUNCT__ "MatAssemblyEnd"
4597 /*@
4598    MatAssemblyEnd - Completes assembling the matrix.  This routine should
4599    be called after MatAssemblyBegin().
4600 
4601    Collective on Mat
4602 
4603    Input Parameters:
4604 +  mat - the matrix
4605 -  type - type of assembly, either MAT_FLUSH_ASSEMBLY or MAT_FINAL_ASSEMBLY
4606 
4607    Options Database Keys:
4608 +  -mat_view_info - Prints info on matrix at conclusion of MatEndAssembly()
4609 .  -mat_view_info_detailed - Prints more detailed info
4610 .  -mat_view - Prints matrix in ASCII format
4611 .  -mat_view_matlab - Prints matrix in Matlab format
4612 .  -mat_view_draw - PetscDraws nonzero structure of matrix, using MatView() and PetscDrawOpenX().
4613 .  -display <name> - Sets display name (default is host)
4614 .  -draw_pause <sec> - Sets number of seconds to pause after display
4615 .  -mat_view_socket - Sends matrix to socket, can be accessed from Matlab (see users manual)
4616 .  -viewer_socket_machine <machine>
4617 .  -viewer_socket_port <port>
4618 .  -mat_view_binary - save matrix to file in binary format
4619 -  -viewer_binary_filename <name>
4620 
4621    Notes:
4622    MatSetValues() generally caches the values.  The matrix is ready to
4623    use only after MatAssemblyBegin() and MatAssemblyEnd() have been called.
4624    Use MAT_FLUSH_ASSEMBLY when switching between ADD_VALUES and INSERT_VALUES
4625    in MatSetValues(); use MAT_FINAL_ASSEMBLY for the final assembly before
4626    using the matrix.
4627 
4628    Level: beginner
4629 
4630 .seealso: MatAssemblyBegin(), MatSetValues(), PetscDrawOpenX(), MatView(), MatAssembled(), PetscViewerSocketOpen()
4631 @*/
4632 PetscErrorCode PETSCMAT_DLLEXPORT MatAssemblyEnd(Mat mat,MatAssemblyType type)
4633 {
4634   PetscErrorCode  ierr;
4635   static PetscInt inassm = 0;
4636   PetscTruth      flg = PETSC_FALSE;
4637 
4638   PetscFunctionBegin;
4639   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4640   PetscValidType(mat,1);
4641 
4642   inassm++;
4643   MatAssemblyEnd_InUse++;
4644   if (MatAssemblyEnd_InUse == 1) { /* Do the logging only the first time through */
4645     ierr = PetscLogEventBegin(MAT_AssemblyEnd,mat,0,0,0);CHKERRQ(ierr);
4646     if (mat->ops->assemblyend) {
4647       ierr = (*mat->ops->assemblyend)(mat,type);CHKERRQ(ierr);
4648     }
4649     ierr = PetscLogEventEnd(MAT_AssemblyEnd,mat,0,0,0);CHKERRQ(ierr);
4650   } else {
4651     if (mat->ops->assemblyend) {
4652       ierr = (*mat->ops->assemblyend)(mat,type);CHKERRQ(ierr);
4653     }
4654   }
4655 
4656   /* Flush assembly is not a true assembly */
4657   if (type != MAT_FLUSH_ASSEMBLY) {
4658     mat->assembled  = PETSC_TRUE; mat->num_ass++;
4659   }
4660   mat->insertmode = NOT_SET_VALUES;
4661   MatAssemblyEnd_InUse--;
4662   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
4663   if (!mat->symmetric_eternal) {
4664     mat->symmetric_set              = PETSC_FALSE;
4665     mat->hermitian_set              = PETSC_FALSE;
4666     mat->structurally_symmetric_set = PETSC_FALSE;
4667   }
4668   if (inassm == 1 && type != MAT_FLUSH_ASSEMBLY) {
4669     ierr = MatView_Private(mat);CHKERRQ(ierr);
4670     ierr = PetscOptionsGetTruth(((PetscObject)mat)->prefix,"-mat_is_symmetric",&flg,PETSC_NULL);CHKERRQ(ierr);
4671     if (flg) {
4672       PetscReal tol = 0.0;
4673       ierr = PetscOptionsGetReal(((PetscObject)mat)->prefix,"-mat_is_symmetric",&tol,PETSC_NULL);CHKERRQ(ierr);
4674       ierr = MatIsSymmetric(mat,tol,&flg);CHKERRQ(ierr);
4675       if (flg) {
4676         ierr = PetscPrintf(((PetscObject)mat)->comm,"Matrix is symmetric (tolerance %G)\n",tol);CHKERRQ(ierr);
4677       } else {
4678         ierr = PetscPrintf(((PetscObject)mat)->comm,"Matrix is not symmetric (tolerance %G)\n",tol);CHKERRQ(ierr);
4679       }
4680     }
4681   }
4682   inassm--;
4683   PetscFunctionReturn(0);
4684 }
4685 
4686 #undef __FUNCT__
4687 #define __FUNCT__ "MatSetOption"
4688 /*@
4689    MatSetOption - Sets a parameter option for a matrix. Some options
4690    may be specific to certain storage formats.  Some options
4691    determine how values will be inserted (or added). Sorted,
4692    row-oriented input will generally assemble the fastest. The default
4693    is row-oriented, nonsorted input.
4694 
4695    Collective on Mat
4696 
4697    Input Parameters:
4698 +  mat - the matrix
4699 .  option - the option, one of those listed below (and possibly others),
4700 -  flg - turn the option on (PETSC_TRUE) or off (PETSC_FALSE)
4701 
4702   Options Describing Matrix Structure:
4703 +    MAT_SYMMETRIC - symmetric in terms of both structure and value
4704 .    MAT_HERMITIAN - transpose is the complex conjugation
4705 .    MAT_STRUCTURALLY_SYMMETRIC - symmetric nonzero structure
4706 -    MAT_SYMMETRY_ETERNAL - if you would like the symmetry/Hermitian flag
4707                             you set to be kept with all future use of the matrix
4708                             including after MatAssemblyBegin/End() which could
4709                             potentially change the symmetry structure, i.e. you
4710                             KNOW the matrix will ALWAYS have the property you set.
4711 
4712 
4713    Options For Use with MatSetValues():
4714    Insert a logically dense subblock, which can be
4715 .    MAT_ROW_ORIENTED - row-oriented (default)
4716 
4717    Note these options reflect the data you pass in with MatSetValues(); it has
4718    nothing to do with how the data is stored internally in the matrix
4719    data structure.
4720 
4721    When (re)assembling a matrix, we can restrict the input for
4722    efficiency/debugging purposes.  These options include
4723 +    MAT_NEW_NONZERO_LOCATIONS - additional insertions will be
4724         allowed if they generate a new nonzero
4725 .    MAT_NEW_DIAGONALS - new diagonals will be allowed (for block diagonal format only)
4726 .    MAT_IGNORE_OFF_PROC_ENTRIES - drops off-processor entries
4727 .    MAT_NEW_NONZERO_LOCATION_ERR - generates an error for new matrix entry
4728 -    MAT_USE_HASH_TABLE - uses a hash table to speed up matrix assembly
4729 
4730    Notes:
4731    Some options are relevant only for particular matrix types and
4732    are thus ignored by others.  Other options are not supported by
4733    certain matrix types and will generate an error message if set.
4734 
4735    If using a Fortran 77 module to compute a matrix, one may need to
4736    use the column-oriented option (or convert to the row-oriented
4737    format).
4738 
4739    MAT_NEW_NONZERO_LOCATIONS set to PETSC_FALSE indicates that any add or insertion
4740    that would generate a new entry in the nonzero structure is instead
4741    ignored.  Thus, if memory has not alredy been allocated for this particular
4742    data, then the insertion is ignored. For dense matrices, in which
4743    the entire array is allocated, no entries are ever ignored.
4744    Set after the first MatAssemblyEnd()
4745 
4746    MAT_NEW_NONZERO_LOCATION_ERR indicates that any add or insertion
4747    that would generate a new entry in the nonzero structure instead produces
4748    an error. (Currently supported for AIJ and BAIJ formats only.)
4749    This is a useful flag when using SAME_NONZERO_PATTERN in calling
4750    KSPSetOperators() to ensure that the nonzero pattern truely does
4751    remain unchanged. Set after the first MatAssemblyEnd()
4752 
4753    MAT_NEW_NONZERO_ALLOCATION_ERR indicates that any add or insertion
4754    that would generate a new entry that has not been preallocated will
4755    instead produce an error. (Currently supported for AIJ and BAIJ formats
4756    only.) This is a useful flag when debugging matrix memory preallocation.
4757 
4758    MAT_IGNORE_OFF_PROC_ENTRIES indicates entries destined for
4759    other processors should be dropped, rather than stashed.
4760    This is useful if you know that the "owning" processor is also
4761    always generating the correct matrix entries, so that PETSc need
4762    not transfer duplicate entries generated on another processor.
4763 
4764    MAT_USE_HASH_TABLE indicates that a hash table be used to improve the
4765    searches during matrix assembly. When this flag is set, the hash table
4766    is created during the first Matrix Assembly. This hash table is
4767    used the next time through, during MatSetVaules()/MatSetVaulesBlocked()
4768    to improve the searching of indices. MAT_NEW_NONZERO_LOCATIONS flag
4769    should be used with MAT_USE_HASH_TABLE flag. This option is currently
4770    supported by MATMPIBAIJ format only.
4771 
4772    MAT_KEEP_NONZERO_PATTERN indicates when MatZeroRows() is called the zeroed entries
4773    are kept in the nonzero structure
4774 
4775    MAT_IGNORE_ZERO_ENTRIES - for AIJ/IS matrices this will stop zero values from creating
4776    a zero location in the matrix
4777 
4778    MAT_USE_INODES - indicates using inode version of the code - works with AIJ and
4779    ROWBS matrix types
4780 
4781    Level: intermediate
4782 
4783    Concepts: matrices^setting options
4784 
4785 @*/
4786 PetscErrorCode PETSCMAT_DLLEXPORT MatSetOption(Mat mat,MatOption op,PetscTruth flg)
4787 {
4788   PetscErrorCode ierr;
4789 
4790   PetscFunctionBegin;
4791   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4792   PetscValidType(mat,1);
4793   if (((int) op) < 0 || ((int) op) >= NUM_MAT_OPTIONS) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Options %d is out of range",(int)op);
4794   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4795   switch (op) {
4796   case MAT_SYMMETRIC:
4797     mat->symmetric                  = flg;
4798     if (flg) mat->structurally_symmetric     = PETSC_TRUE;
4799     mat->symmetric_set              = PETSC_TRUE;
4800     mat->structurally_symmetric_set = flg;
4801     break;
4802   case MAT_HERMITIAN:
4803     mat->hermitian                  = flg;
4804     if (flg) mat->structurally_symmetric     = PETSC_TRUE;
4805     mat->hermitian_set              = PETSC_TRUE;
4806     mat->structurally_symmetric_set = flg;
4807     break;
4808   case MAT_STRUCTURALLY_SYMMETRIC:
4809     mat->structurally_symmetric     = flg;
4810     mat->structurally_symmetric_set = PETSC_TRUE;
4811     break;
4812   case MAT_SYMMETRY_ETERNAL:
4813     mat->symmetric_eternal          = flg;
4814     break;
4815   default:
4816     break;
4817   }
4818   if (mat->ops->setoption) {
4819     ierr = (*mat->ops->setoption)(mat,op,flg);CHKERRQ(ierr);
4820   }
4821   PetscFunctionReturn(0);
4822 }
4823 
4824 #undef __FUNCT__
4825 #define __FUNCT__ "MatZeroEntries"
4826 /*@
4827    MatZeroEntries - Zeros all entries of a matrix.  For sparse matrices
4828    this routine retains the old nonzero structure.
4829 
4830    Collective on Mat
4831 
4832    Input Parameters:
4833 .  mat - the matrix
4834 
4835    Level: intermediate
4836 
4837    Concepts: matrices^zeroing
4838 
4839 .seealso: MatZeroRows()
4840 @*/
4841 PetscErrorCode PETSCMAT_DLLEXPORT MatZeroEntries(Mat mat)
4842 {
4843   PetscErrorCode ierr;
4844 
4845   PetscFunctionBegin;
4846   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4847   PetscValidType(mat,1);
4848   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4849   if (mat->insertmode != NOT_SET_VALUES) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for matrices where you have set values but not yet assembled");
4850   if (!mat->ops->zeroentries) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
4851   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4852 
4853   ierr = PetscLogEventBegin(MAT_ZeroEntries,mat,0,0,0);CHKERRQ(ierr);
4854   ierr = (*mat->ops->zeroentries)(mat);CHKERRQ(ierr);
4855   ierr = PetscLogEventEnd(MAT_ZeroEntries,mat,0,0,0);CHKERRQ(ierr);
4856   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
4857   PetscFunctionReturn(0);
4858 }
4859 
4860 #undef __FUNCT__
4861 #define __FUNCT__ "MatZeroRows"
4862 /*@C
4863    MatZeroRows - Zeros all entries (except possibly the main diagonal)
4864    of a set of rows of a matrix.
4865 
4866    Collective on Mat
4867 
4868    Input Parameters:
4869 +  mat - the matrix
4870 .  numRows - the number of rows to remove
4871 .  rows - the global row indices
4872 -  diag - value put in all diagonals of eliminated rows (0.0 will even eliminate diagonal entry)
4873 
4874    Notes:
4875    For the AIJ and BAIJ matrix formats this removes the old nonzero structure,
4876    but does not release memory.  For the dense and block diagonal
4877    formats this does not alter the nonzero structure.
4878 
4879    If the option MatSetOption(mat,MAT_KEEP_NONZERO_PATTERN,PETSC_TRUE) the nonzero structure
4880    of the matrix is not changed (even for AIJ and BAIJ matrices) the values are
4881    merely zeroed.
4882 
4883    The user can set a value in the diagonal entry (or for the AIJ and
4884    row formats can optionally remove the main diagonal entry from the
4885    nonzero structure as well, by passing 0.0 as the final argument).
4886 
4887    For the parallel case, all processes that share the matrix (i.e.,
4888    those in the communicator used for matrix creation) MUST call this
4889    routine, regardless of whether any rows being zeroed are owned by
4890    them.
4891 
4892    Each processor can indicate any rows in the entire matrix to be zeroed (i.e. each process does NOT have to
4893    list only rows local to itself).
4894 
4895    Level: intermediate
4896 
4897    Concepts: matrices^zeroing rows
4898 
4899 .seealso: MatZeroRowsIS(), MatZeroEntries(), MatZeroRowsLocal(), MatSetOption()
4900 @*/
4901 PetscErrorCode PETSCMAT_DLLEXPORT MatZeroRows(Mat mat,PetscInt numRows,const PetscInt rows[],PetscScalar diag)
4902 {
4903   PetscErrorCode ierr;
4904 
4905   PetscFunctionBegin;
4906   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4907   PetscValidType(mat,1);
4908   if (numRows) PetscValidIntPointer(rows,3);
4909   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4910   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4911   if (!mat->ops->zerorows) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
4912   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4913 
4914   ierr = (*mat->ops->zerorows)(mat,numRows,rows,diag);CHKERRQ(ierr);
4915   ierr = MatView_Private(mat);CHKERRQ(ierr);
4916   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
4917   PetscFunctionReturn(0);
4918 }
4919 
4920 #undef __FUNCT__
4921 #define __FUNCT__ "MatZeroRowsIS"
4922 /*@C
4923    MatZeroRowsIS - Zeros all entries (except possibly the main diagonal)
4924    of a set of rows of a matrix.
4925 
4926    Collective on Mat
4927 
4928    Input Parameters:
4929 +  mat - the matrix
4930 .  is - index set of rows to remove
4931 -  diag - value put in all diagonals of eliminated rows
4932 
4933    Notes:
4934    For the AIJ and BAIJ matrix formats this removes the old nonzero structure,
4935    but does not release memory.  For the dense and block diagonal
4936    formats this does not alter the nonzero structure.
4937 
4938    If the option MatSetOption(mat,MAT_KEEP_NONZERO_PATTERN,PETSC_TRUE) the nonzero structure
4939    of the matrix is not changed (even for AIJ and BAIJ matrices) the values are
4940    merely zeroed.
4941 
4942    The user can set a value in the diagonal entry (or for the AIJ and
4943    row formats can optionally remove the main diagonal entry from the
4944    nonzero structure as well, by passing 0.0 as the final argument).
4945 
4946    For the parallel case, all processes that share the matrix (i.e.,
4947    those in the communicator used for matrix creation) MUST call this
4948    routine, regardless of whether any rows being zeroed are owned by
4949    them.
4950 
4951    Each processor should list the rows that IT wants zeroed
4952 
4953    Level: intermediate
4954 
4955    Concepts: matrices^zeroing rows
4956 
4957 .seealso: MatZeroRows(), MatZeroEntries(), MatZeroRowsLocal(), MatSetOption()
4958 @*/
4959 PetscErrorCode PETSCMAT_DLLEXPORT MatZeroRowsIS(Mat mat,IS is,PetscScalar diag)
4960 {
4961   PetscInt       numRows;
4962   const PetscInt *rows;
4963   PetscErrorCode ierr;
4964 
4965   PetscFunctionBegin;
4966   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4967   PetscValidType(mat,1);
4968   PetscValidHeaderSpecific(is,IS_COOKIE,2);
4969   ierr = ISGetLocalSize(is,&numRows);CHKERRQ(ierr);
4970   ierr = ISGetIndices(is,&rows);CHKERRQ(ierr);
4971   ierr = MatZeroRows(mat,numRows,rows,diag);CHKERRQ(ierr);
4972   ierr = ISRestoreIndices(is,&rows);CHKERRQ(ierr);
4973   PetscFunctionReturn(0);
4974 }
4975 
4976 #undef __FUNCT__
4977 #define __FUNCT__ "MatZeroRowsLocal"
4978 /*@C
4979    MatZeroRowsLocal - Zeros all entries (except possibly the main diagonal)
4980    of a set of rows of a matrix; using local numbering of rows.
4981 
4982    Collective on Mat
4983 
4984    Input Parameters:
4985 +  mat - the matrix
4986 .  numRows - the number of rows to remove
4987 .  rows - the global row indices
4988 -  diag - value put in all diagonals of eliminated rows
4989 
4990    Notes:
4991    Before calling MatZeroRowsLocal(), the user must first set the
4992    local-to-global mapping by calling MatSetLocalToGlobalMapping().
4993 
4994    For the AIJ matrix formats this removes the old nonzero structure,
4995    but does not release memory.  For the dense and block diagonal
4996    formats this does not alter the nonzero structure.
4997 
4998    If the option MatSetOption(mat,MAT_KEEP_NONZERO_PATTERN,PETSC_TRUE) the nonzero structure
4999    of the matrix is not changed (even for AIJ and BAIJ matrices) the values are
5000    merely zeroed.
5001 
5002    The user can set a value in the diagonal entry (or for the AIJ and
5003    row formats can optionally remove the main diagonal entry from the
5004    nonzero structure as well, by passing 0.0 as the final argument).
5005 
5006    Level: intermediate
5007 
5008    Concepts: matrices^zeroing
5009 
5010 .seealso: MatZeroRows(), MatZeroRowsLocalIS(), MatZeroEntries(), MatZeroRows(), MatSetLocalToGlobalMapping
5011 @*/
5012 PetscErrorCode PETSCMAT_DLLEXPORT MatZeroRowsLocal(Mat mat,PetscInt numRows,const PetscInt rows[],PetscScalar diag)
5013 {
5014   PetscErrorCode ierr;
5015 
5016   PetscFunctionBegin;
5017   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5018   PetscValidType(mat,1);
5019   if (numRows) PetscValidIntPointer(rows,3);
5020   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
5021   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
5022   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5023 
5024   if (mat->ops->zerorowslocal) {
5025     ierr = (*mat->ops->zerorowslocal)(mat,numRows,rows,diag);CHKERRQ(ierr);
5026   } else {
5027     IS             is, newis;
5028     const PetscInt *newRows;
5029 
5030     if (!mat->mapping) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Need to provide local to global mapping to matrix first");
5031     ierr = ISCreateGeneral(PETSC_COMM_SELF,numRows,rows,&is);CHKERRQ(ierr);
5032     ierr = ISLocalToGlobalMappingApplyIS(mat->mapping,is,&newis);CHKERRQ(ierr);
5033     ierr = ISGetIndices(newis,&newRows);CHKERRQ(ierr);
5034     ierr = (*mat->ops->zerorows)(mat,numRows,newRows,diag);CHKERRQ(ierr);
5035     ierr = ISRestoreIndices(newis,&newRows);CHKERRQ(ierr);
5036     ierr = ISDestroy(newis);CHKERRQ(ierr);
5037     ierr = ISDestroy(is);CHKERRQ(ierr);
5038   }
5039   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
5040   PetscFunctionReturn(0);
5041 }
5042 
5043 #undef __FUNCT__
5044 #define __FUNCT__ "MatZeroRowsLocalIS"
5045 /*@C
5046    MatZeroRowsLocalIS - Zeros all entries (except possibly the main diagonal)
5047    of a set of rows of a matrix; using local numbering of rows.
5048 
5049    Collective on Mat
5050 
5051    Input Parameters:
5052 +  mat - the matrix
5053 .  is - index set of rows to remove
5054 -  diag - value put in all diagonals of eliminated rows
5055 
5056    Notes:
5057    Before calling MatZeroRowsLocalIS(), the user must first set the
5058    local-to-global mapping by calling MatSetLocalToGlobalMapping().
5059 
5060    For the AIJ matrix formats this removes the old nonzero structure,
5061    but does not release memory.  For the dense and block diagonal
5062    formats this does not alter the nonzero structure.
5063 
5064    If the option MatSetOption(mat,MAT_KEEP_NONZERO_PATTERN,PETSC_TRUE) the nonzero structure
5065    of the matrix is not changed (even for AIJ and BAIJ matrices) the values are
5066    merely zeroed.
5067 
5068    The user can set a value in the diagonal entry (or for the AIJ and
5069    row formats can optionally remove the main diagonal entry from the
5070    nonzero structure as well, by passing 0.0 as the final argument).
5071 
5072    Level: intermediate
5073 
5074    Concepts: matrices^zeroing
5075 
5076 .seealso: MatZeroRows(), MatZeroRowsLocal(), MatZeroEntries(), MatZeroRows(), MatSetLocalToGlobalMapping
5077 @*/
5078 PetscErrorCode PETSCMAT_DLLEXPORT MatZeroRowsLocalIS(Mat mat,IS is,PetscScalar diag)
5079 {
5080   PetscErrorCode ierr;
5081   PetscInt       numRows;
5082   const PetscInt *rows;
5083 
5084   PetscFunctionBegin;
5085   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5086   PetscValidType(mat,1);
5087   PetscValidHeaderSpecific(is,IS_COOKIE,2);
5088   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
5089   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
5090   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5091 
5092   ierr = ISGetLocalSize(is,&numRows);CHKERRQ(ierr);
5093   ierr = ISGetIndices(is,&rows);CHKERRQ(ierr);
5094   ierr = MatZeroRowsLocal(mat,numRows,rows,diag);CHKERRQ(ierr);
5095   ierr = ISRestoreIndices(is,&rows);CHKERRQ(ierr);
5096   PetscFunctionReturn(0);
5097 }
5098 
5099 #undef __FUNCT__
5100 #define __FUNCT__ "MatGetSize"
5101 /*@
5102    MatGetSize - Returns the numbers of rows and columns in a matrix.
5103 
5104    Not Collective
5105 
5106    Input Parameter:
5107 .  mat - the matrix
5108 
5109    Output Parameters:
5110 +  m - the number of global rows
5111 -  n - the number of global columns
5112 
5113    Note: both output parameters can be PETSC_NULL on input.
5114 
5115    Level: beginner
5116 
5117    Concepts: matrices^size
5118 
5119 .seealso: MatGetLocalSize()
5120 @*/
5121 PetscErrorCode PETSCMAT_DLLEXPORT MatGetSize(Mat mat,PetscInt *m,PetscInt* n)
5122 {
5123   PetscFunctionBegin;
5124   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5125   if (m) *m = mat->rmap->N;
5126   if (n) *n = mat->cmap->N;
5127   PetscFunctionReturn(0);
5128 }
5129 
5130 #undef __FUNCT__
5131 #define __FUNCT__ "MatGetLocalSize"
5132 /*@
5133    MatGetLocalSize - Returns the number of rows and columns in a matrix
5134    stored locally.  This information may be implementation dependent, so
5135    use with care.
5136 
5137    Not Collective
5138 
5139    Input Parameters:
5140 .  mat - the matrix
5141 
5142    Output Parameters:
5143 +  m - the number of local rows
5144 -  n - the number of local columns
5145 
5146    Note: both output parameters can be PETSC_NULL on input.
5147 
5148    Level: beginner
5149 
5150    Concepts: matrices^local size
5151 
5152 .seealso: MatGetSize()
5153 @*/
5154 PetscErrorCode PETSCMAT_DLLEXPORT MatGetLocalSize(Mat mat,PetscInt *m,PetscInt* n)
5155 {
5156   PetscFunctionBegin;
5157   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5158   if (m) PetscValidIntPointer(m,2);
5159   if (n) PetscValidIntPointer(n,3);
5160   if (m) *m = mat->rmap->n;
5161   if (n) *n = mat->cmap->n;
5162   PetscFunctionReturn(0);
5163 }
5164 
5165 #undef __FUNCT__
5166 #define __FUNCT__ "MatGetOwnershipRangeColumn"
5167 /*@
5168    MatGetOwnershipRangeColumn - Returns the range of matrix columns owned by
5169    this processor.
5170 
5171    Not Collective, unless matrix has not been allocated, then collective on Mat
5172 
5173    Input Parameters:
5174 .  mat - the matrix
5175 
5176    Output Parameters:
5177 +  m - the global index of the first local column
5178 -  n - one more than the global index of the last local column
5179 
5180    Notes: both output parameters can be PETSC_NULL on input.
5181 
5182    Level: developer
5183 
5184    Concepts: matrices^column ownership
5185 
5186 .seealso:  MatGetOwnershipRange(), MatGetOwnershipRanges(), MatGetOwnershipRangesColumn()
5187 
5188 @*/
5189 PetscErrorCode PETSCMAT_DLLEXPORT MatGetOwnershipRangeColumn(Mat mat,PetscInt *m,PetscInt* n)
5190 {
5191   PetscErrorCode ierr;
5192 
5193   PetscFunctionBegin;
5194   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5195   PetscValidType(mat,1);
5196   if (m) PetscValidIntPointer(m,2);
5197   if (n) PetscValidIntPointer(n,3);
5198   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5199   if (m) *m = mat->cmap->rstart;
5200   if (n) *n = mat->cmap->rend;
5201   PetscFunctionReturn(0);
5202 }
5203 
5204 #undef __FUNCT__
5205 #define __FUNCT__ "MatGetOwnershipRange"
5206 /*@
5207    MatGetOwnershipRange - Returns the range of matrix rows owned by
5208    this processor, assuming that the matrix is laid out with the first
5209    n1 rows on the first processor, the next n2 rows on the second, etc.
5210    For certain parallel layouts this range may not be well defined.
5211 
5212    Not Collective, unless matrix has not been allocated, then collective on Mat
5213 
5214    Input Parameters:
5215 .  mat - the matrix
5216 
5217    Output Parameters:
5218 +  m - the global index of the first local row
5219 -  n - one more than the global index of the last local row
5220 
5221    Note: both output parameters can be PETSC_NULL on input.
5222 
5223    Level: beginner
5224 
5225    Concepts: matrices^row ownership
5226 
5227 .seealso:   MatGetOwnershipRanges(), MatGetOwnershipRangeColumn(), MatGetOwnershipRangesColumn()
5228 
5229 @*/
5230 PetscErrorCode PETSCMAT_DLLEXPORT MatGetOwnershipRange(Mat mat,PetscInt *m,PetscInt* n)
5231 {
5232   PetscErrorCode ierr;
5233 
5234   PetscFunctionBegin;
5235   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5236   PetscValidType(mat,1);
5237   if (m) PetscValidIntPointer(m,2);
5238   if (n) PetscValidIntPointer(n,3);
5239   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5240   if (m) *m = mat->rmap->rstart;
5241   if (n) *n = mat->rmap->rend;
5242   PetscFunctionReturn(0);
5243 }
5244 
5245 #undef __FUNCT__
5246 #define __FUNCT__ "MatGetOwnershipRanges"
5247 /*@C
5248    MatGetOwnershipRanges - Returns the range of matrix rows owned by
5249    each process
5250 
5251    Not Collective, unless matrix has not been allocated, then collective on Mat
5252 
5253    Input Parameters:
5254 .  mat - the matrix
5255 
5256    Output Parameters:
5257 .  ranges - start of each processors portion plus one more then the total length at the end
5258 
5259    Level: beginner
5260 
5261    Concepts: matrices^row ownership
5262 
5263 .seealso:   MatGetOwnershipRange(), MatGetOwnershipRangeColumn(), MatGetOwnershipRangesColumn()
5264 
5265 @*/
5266 PetscErrorCode PETSCMAT_DLLEXPORT MatGetOwnershipRanges(Mat mat,const PetscInt **ranges)
5267 {
5268   PetscErrorCode ierr;
5269 
5270   PetscFunctionBegin;
5271   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5272   PetscValidType(mat,1);
5273   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5274   ierr = PetscMapGetRanges(mat->rmap,ranges);CHKERRQ(ierr);
5275   PetscFunctionReturn(0);
5276 }
5277 
5278 #undef __FUNCT__
5279 #define __FUNCT__ "MatGetOwnershipRangesColumn"
5280 /*@C
5281    MatGetOwnershipRangesColumn - Returns the range of local columns for each process
5282 
5283    Not Collective, unless matrix has not been allocated, then collective on Mat
5284 
5285    Input Parameters:
5286 .  mat - the matrix
5287 
5288    Output Parameters:
5289 .  ranges - start of each processors portion plus one more then the total length at the end
5290 
5291    Level: beginner
5292 
5293    Concepts: matrices^column ownership
5294 
5295 .seealso:   MatGetOwnershipRange(), MatGetOwnershipRangeColumn(), MatGetOwnershipRanges()
5296 
5297 @*/
5298 PetscErrorCode PETSCMAT_DLLEXPORT MatGetOwnershipRangesColumn(Mat mat,const PetscInt **ranges)
5299 {
5300   PetscErrorCode ierr;
5301 
5302   PetscFunctionBegin;
5303   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5304   PetscValidType(mat,1);
5305   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5306   ierr = PetscMapGetRanges(mat->cmap,ranges);CHKERRQ(ierr);
5307   PetscFunctionReturn(0);
5308 }
5309 
5310 #undef __FUNCT__
5311 #define __FUNCT__ "MatILUFactorSymbolic"
5312 /*@C
5313    MatILUFactorSymbolic - Performs symbolic ILU factorization of a matrix.
5314    Uses levels of fill only, not drop tolerance. Use MatLUFactorNumeric()
5315    to complete the factorization.
5316 
5317    Collective on Mat
5318 
5319    Input Parameters:
5320 +  mat - the matrix
5321 .  row - row permutation
5322 .  column - column permutation
5323 -  info - structure containing
5324 $      levels - number of levels of fill.
5325 $      expected fill - as ratio of original fill.
5326 $      1 or 0 - indicating force fill on diagonal (improves robustness for matrices
5327                 missing diagonal entries)
5328 
5329    Output Parameters:
5330 .  fact - new matrix that has been symbolically factored
5331 
5332    Notes:
5333    See the users manual for additional information about
5334    choosing the fill factor for better efficiency.
5335 
5336    Most users should employ the simplified KSP interface for linear solvers
5337    instead of working directly with matrix algebra routines such as this.
5338    See, e.g., KSPCreate().
5339 
5340    Level: developer
5341 
5342   Concepts: matrices^symbolic LU factorization
5343   Concepts: matrices^factorization
5344   Concepts: LU^symbolic factorization
5345 
5346 .seealso: MatLUFactorSymbolic(), MatLUFactorNumeric(), MatCholeskyFactor()
5347           MatGetOrdering(), MatFactorInfo
5348 
5349     Developer Note: fortran interface is not autogenerated as the f90
5350     interface defintion cannot be generated correctly [due to MatFactorInfo]
5351 
5352 @*/
5353 PetscErrorCode PETSCMAT_DLLEXPORT MatILUFactorSymbolic(Mat fact,Mat mat,IS row,IS col,const MatFactorInfo *info)
5354 {
5355   PetscErrorCode ierr;
5356 
5357   PetscFunctionBegin;
5358   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5359   PetscValidType(mat,1);
5360   PetscValidHeaderSpecific(row,IS_COOKIE,2);
5361   PetscValidHeaderSpecific(col,IS_COOKIE,3);
5362   PetscValidPointer(info,4);
5363   PetscValidPointer(fact,5);
5364   if (info->levels < 0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Levels of fill negative %D",(PetscInt)info->levels);
5365   if (info->fill < 1.0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Expected fill less than 1.0 %G",info->fill);
5366   if (!(fact)->ops->ilufactorsymbolic) SETERRQ1(PETSC_ERR_SUP,"Matrix type %s  symbolic ILU",((PetscObject)mat)->type_name);
5367   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
5368   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
5369   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5370 
5371   ierr = PetscLogEventBegin(MAT_ILUFactorSymbolic,mat,row,col,0);CHKERRQ(ierr);
5372   ierr = (fact->ops->ilufactorsymbolic)(fact,mat,row,col,info);CHKERRQ(ierr);
5373   ierr = PetscLogEventEnd(MAT_ILUFactorSymbolic,mat,row,col,0);CHKERRQ(ierr);
5374   PetscFunctionReturn(0);
5375 }
5376 
5377 #undef __FUNCT__
5378 #define __FUNCT__ "MatICCFactorSymbolic"
5379 /*@C
5380    MatICCFactorSymbolic - Performs symbolic incomplete
5381    Cholesky factorization for a symmetric matrix.  Use
5382    MatCholeskyFactorNumeric() to complete the factorization.
5383 
5384    Collective on Mat
5385 
5386    Input Parameters:
5387 +  mat - the matrix
5388 .  perm - row and column permutation
5389 -  info - structure containing
5390 $      levels - number of levels of fill.
5391 $      expected fill - as ratio of original fill.
5392 
5393    Output Parameter:
5394 .  fact - the factored matrix
5395 
5396    Notes:
5397    Most users should employ the KSP interface for linear solvers
5398    instead of working directly with matrix algebra routines such as this.
5399    See, e.g., KSPCreate().
5400 
5401    Level: developer
5402 
5403   Concepts: matrices^symbolic incomplete Cholesky factorization
5404   Concepts: matrices^factorization
5405   Concepts: Cholsky^symbolic factorization
5406 
5407 .seealso: MatCholeskyFactorNumeric(), MatCholeskyFactor(), MatFactorInfo
5408 
5409     Developer Note: fortran interface is not autogenerated as the f90
5410     interface defintion cannot be generated correctly [due to MatFactorInfo]
5411 
5412 @*/
5413 PetscErrorCode PETSCMAT_DLLEXPORT MatICCFactorSymbolic(Mat fact,Mat mat,IS perm,const MatFactorInfo *info)
5414 {
5415   PetscErrorCode ierr;
5416 
5417   PetscFunctionBegin;
5418   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5419   PetscValidType(mat,1);
5420   PetscValidHeaderSpecific(perm,IS_COOKIE,2);
5421   PetscValidPointer(info,3);
5422   PetscValidPointer(fact,4);
5423   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
5424   if (info->levels < 0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Levels negative %D",(PetscInt) info->levels);
5425   if (info->fill < 1.0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Expected fill less than 1.0 %G",info->fill);
5426   if (!(fact)->ops->iccfactorsymbolic) SETERRQ1(PETSC_ERR_SUP,"Matrix type %s  symbolic ICC",((PetscObject)mat)->type_name);
5427   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
5428   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5429 
5430   ierr = PetscLogEventBegin(MAT_ICCFactorSymbolic,mat,perm,0,0);CHKERRQ(ierr);
5431   ierr = (fact->ops->iccfactorsymbolic)(fact,mat,perm,info);CHKERRQ(ierr);
5432   ierr = PetscLogEventEnd(MAT_ICCFactorSymbolic,mat,perm,0,0);CHKERRQ(ierr);
5433   PetscFunctionReturn(0);
5434 }
5435 
5436 #undef __FUNCT__
5437 #define __FUNCT__ "MatILUDTFactorSymbolic"
5438 /*@
5439    MatILUDTFactorSymbolic - Performs symbolic pivoting drop-tolerance ILU factorization of a matrix.
5440    User provides the drop tolerance(dt) and the maximum nonzeros to be allowed per row(dtcount).
5441    Use MatILUDTFactorNumeric() to complete the factorization.
5442 
5443    Collective on Mat
5444 
5445    Input Parameters:
5446 +  mat - the matrix
5447 .  row - row permutation
5448 .  column - column permutation
5449 -  info - structure containing
5450 $      dt - drop tolerance.
5451 $      dtcount - maximum nonzeros to be allowed per row.
5452 
5453    Output Parameters:
5454 .  fact - factor matrix with memory preallocated
5455 
5456    Notes:
5457    See the ILUT algorithm written by Yousef Saad.
5458 
5459    Most users should employ the simplified KSP interface for linear solvers
5460    instead of working directly with matrix algebra routines such as this.
5461    See, e.g., KSPCreate().
5462 
5463    Level: developer
5464 
5465   Concepts: matrices^symbolic ILU factorization
5466   Concepts: matrices^factorization
5467 
5468 .seealso: MatILUDTFactorNumeric()
5469           MatGetOrdering(), MatGetFactor(), MatFactorInfo
5470 
5471 @*/
5472 PetscErrorCode PETSCMAT_DLLEXPORT MatILUDTFactorSymbolic(Mat fact,Mat mat,IS row,IS col,const MatFactorInfo *info)
5473 {
5474   PetscErrorCode ierr;
5475 
5476   PetscFunctionBegin;
5477   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5478   PetscValidType(mat,1);
5479   PetscValidHeaderSpecific(row,IS_COOKIE,2);
5480   PetscValidHeaderSpecific(col,IS_COOKIE,3);
5481   PetscValidPointer(info,4);
5482   PetscValidPointer(fact,5);
5483   if (info->dt < 0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"drop tolerance negative %G",(PetscInt)info->dt);
5484   if (info->dtcount < 0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"nonzeros per row %D <0",info->dtcount);
5485   if (!(fact)->ops->iludtfactorsymbolic) SETERRQ1(PETSC_ERR_SUP,"Matrix type %s  symbolic ILUDT",((PetscObject)mat)->type_name);
5486   if (mat->rmap->N != mat->cmap->N) SETERRQ(PETSC_ERR_ARG_WRONG,"matrix must be square");
5487   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
5488   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
5489   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5490 
5491   ierr = PetscLogEventBegin(MAT_ILUDTFactorSymbolic,mat,row,col,0);CHKERRQ(ierr);
5492   ierr = (fact->ops->iludtfactorsymbolic)(fact,mat,row,col,info);CHKERRQ(ierr);
5493   ierr = PetscLogEventEnd(MAT_ILUDTFactorSymbolic,mat,row,col,0);CHKERRQ(ierr);
5494   PetscFunctionReturn(0);
5495 }
5496 
5497 #undef __FUNCT__
5498 #define __FUNCT__ "MatILUDTFactorNumeric"
5499 /*@
5500    MatILUDTFactorNumeric - Performs numeric pivoting drop-tolerance ILU factorization of a matrix.
5501    Call this routine after first calling MatILUDTFactorSymbolic().
5502 
5503    Collective on Mat
5504 
5505    Input Parameters:
5506 +  fact - the factor matrix obtained with MatGetFactor()
5507 .  mat - the matrix
5508 -  info - options for factorization
5509 
5510    Output Parameters:
5511 .  fact - assembled factor matrix
5512 
5513    Notes:
5514    Most users should employ the simplified KSP interface for linear solvers
5515    instead of working directly with matrix algebra routines such as this.
5516    See, e.g., KSPCreate().
5517 
5518    Level: developer
5519 
5520 .seealso: MatILUDTFactorSymbolic()
5521 @*/
5522 PetscErrorCode PETSCMAT_DLLEXPORT MatILUDTFactorNumeric(Mat fact,Mat mat,const MatFactorInfo *info)
5523 {
5524   PetscErrorCode ierr;
5525 
5526   PetscFunctionBegin;
5527   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5528   PetscValidType(mat,1);
5529   PetscValidPointer(fact,2);
5530   PetscValidHeaderSpecific(fact,MAT_COOKIE,2);
5531   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
5532   if (mat->rmap->N != (fact)->rmap->N || mat->cmap->N != (fact)->cmap->N) {
5533     SETERRQ4(PETSC_ERR_ARG_SIZ,"Mat mat,Mat fact: global dimensions are different %D should = %D %D should = %D",mat->rmap->N,(fact)->rmap->N,mat->cmap->N,(fact)->cmap->N);
5534   }
5535   if (!(fact)->ops->iludtfactornumeric) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
5536   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5537   ierr = PetscLogEventBegin(MAT_ILUDTFactorNumeric,mat,fact,0,0);CHKERRQ(ierr);
5538   ierr = (fact->ops->iludtfactornumeric)(fact,mat,info);CHKERRQ(ierr);
5539   ierr = PetscLogEventEnd(MAT_ILUDTFactorNumeric,mat,fact,0,0);CHKERRQ(ierr);
5540 
5541   ierr = MatView_Private(fact);CHKERRQ(ierr);
5542   ierr = PetscObjectStateIncrease((PetscObject)fact);CHKERRQ(ierr);
5543   PetscFunctionReturn(0);
5544 }
5545 
5546 #undef __FUNCT__
5547 #define __FUNCT__ "MatGetArray"
5548 /*@C
5549    MatGetArray - Returns a pointer to the element values in the matrix.
5550    The result of this routine is dependent on the underlying matrix data
5551    structure, and may not even work for certain matrix types.  You MUST
5552    call MatRestoreArray() when you no longer need to access the array.
5553 
5554    Not Collective
5555 
5556    Input Parameter:
5557 .  mat - the matrix
5558 
5559    Output Parameter:
5560 .  v - the location of the values
5561 
5562 
5563    Fortran Note:
5564    This routine is used differently from Fortran, e.g.,
5565 .vb
5566         Mat         mat
5567         PetscScalar mat_array(1)
5568         PetscOffset i_mat
5569         PetscErrorCode ierr
5570         call MatGetArray(mat,mat_array,i_mat,ierr)
5571 
5572   C  Access first local entry in matrix; note that array is
5573   C  treated as one dimensional
5574         value = mat_array(i_mat + 1)
5575 
5576         [... other code ...]
5577         call MatRestoreArray(mat,mat_array,i_mat,ierr)
5578 .ve
5579 
5580    See the Fortran chapter of the users manual and
5581    petsc/src/mat/examples/tests for details.
5582 
5583    Level: advanced
5584 
5585    Concepts: matrices^access array
5586 
5587 .seealso: MatRestoreArray(), MatGetArrayF90(), MatGetRowIJ()
5588 @*/
5589 PetscErrorCode PETSCMAT_DLLEXPORT MatGetArray(Mat mat,PetscScalar *v[])
5590 {
5591   PetscErrorCode ierr;
5592 
5593   PetscFunctionBegin;
5594   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5595   PetscValidType(mat,1);
5596   PetscValidPointer(v,2);
5597   if (!mat->ops->getarray) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
5598   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5599   ierr = (*mat->ops->getarray)(mat,v);CHKERRQ(ierr);
5600   CHKMEMQ;
5601   PetscFunctionReturn(0);
5602 }
5603 
5604 #undef __FUNCT__
5605 #define __FUNCT__ "MatRestoreArray"
5606 /*@C
5607    MatRestoreArray - Restores the matrix after MatGetArray() has been called.
5608 
5609    Not Collective
5610 
5611    Input Parameter:
5612 +  mat - the matrix
5613 -  v - the location of the values
5614 
5615    Fortran Note:
5616    This routine is used differently from Fortran, e.g.,
5617 .vb
5618         Mat         mat
5619         PetscScalar mat_array(1)
5620         PetscOffset i_mat
5621         PetscErrorCode ierr
5622         call MatGetArray(mat,mat_array,i_mat,ierr)
5623 
5624   C  Access first local entry in matrix; note that array is
5625   C  treated as one dimensional
5626         value = mat_array(i_mat + 1)
5627 
5628         [... other code ...]
5629         call MatRestoreArray(mat,mat_array,i_mat,ierr)
5630 .ve
5631 
5632    See the Fortran chapter of the users manual and
5633    petsc/src/mat/examples/tests for details
5634 
5635    Level: advanced
5636 
5637 .seealso: MatGetArray(), MatRestoreArrayF90()
5638 @*/
5639 PetscErrorCode PETSCMAT_DLLEXPORT MatRestoreArray(Mat mat,PetscScalar *v[])
5640 {
5641   PetscErrorCode ierr;
5642 
5643   PetscFunctionBegin;
5644   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5645   PetscValidType(mat,1);
5646   PetscValidPointer(v,2);
5647 #if defined(PETSC_USE_DEBUG)
5648   CHKMEMQ;
5649 #endif
5650   if (!mat->ops->restorearray) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
5651   ierr = (*mat->ops->restorearray)(mat,v);CHKERRQ(ierr);
5652   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
5653   PetscFunctionReturn(0);
5654 }
5655 
5656 #undef __FUNCT__
5657 #define __FUNCT__ "MatGetSubMatrices"
5658 /*@C
5659    MatGetSubMatrices - Extracts several submatrices from a matrix. If submat
5660    points to an array of valid matrices, they may be reused to store the new
5661    submatrices.
5662 
5663    Collective on Mat
5664 
5665    Input Parameters:
5666 +  mat - the matrix
5667 .  n   - the number of submatrixes to be extracted (on this processor, may be zero)
5668 .  irow, icol - index sets of rows and columns to extract
5669 -  scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
5670 
5671    Output Parameter:
5672 .  submat - the array of submatrices
5673 
5674    Notes:
5675    MatGetSubMatrices() can extract ONLY sequential submatrices
5676    (from both sequential and parallel matrices). Use MatGetSubMatrix()
5677    to extract a parallel submatrix.
5678 
5679    When extracting submatrices from a parallel matrix, each processor can
5680    form a different submatrix by setting the rows and columns of its
5681    individual index sets according to the local submatrix desired.
5682 
5683    When finished using the submatrices, the user should destroy
5684    them with MatDestroyMatrices().
5685 
5686    MAT_REUSE_MATRIX can only be used when the nonzero structure of the
5687    original matrix has not changed from that last call to MatGetSubMatrices().
5688 
5689    This routine creates the matrices in submat; you should NOT create them before
5690    calling it. It also allocates the array of matrix pointers submat.
5691 
5692    For BAIJ matrices the index sets must respect the block structure, that is if they
5693    request one row/column in a block, they must request all rows/columns that are in
5694    that block. For example, if the block size is 2 you cannot request just row 0 and
5695    column 0.
5696 
5697    Fortran Note:
5698    The Fortran interface is slightly different from that given below; it
5699    requires one to pass in  as submat a Mat (integer) array of size at least m.
5700 
5701    Level: advanced
5702 
5703    Concepts: matrices^accessing submatrices
5704    Concepts: submatrices
5705 
5706 .seealso: MatDestroyMatrices(), MatGetSubMatrix(), MatGetRow(), MatGetDiagonal(), MatReuse
5707 @*/
5708 PetscErrorCode PETSCMAT_DLLEXPORT MatGetSubMatrices(Mat mat,PetscInt n,const IS irow[],const IS icol[],MatReuse scall,Mat *submat[])
5709 {
5710   PetscErrorCode ierr;
5711   PetscInt        i;
5712   PetscTruth      eq;
5713 
5714   PetscFunctionBegin;
5715   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5716   PetscValidType(mat,1);
5717   if (n) {
5718     PetscValidPointer(irow,3);
5719     PetscValidHeaderSpecific(*irow,IS_COOKIE,3);
5720     PetscValidPointer(icol,4);
5721     PetscValidHeaderSpecific(*icol,IS_COOKIE,4);
5722   }
5723   PetscValidPointer(submat,6);
5724   if (n && scall == MAT_REUSE_MATRIX) {
5725     PetscValidPointer(*submat,6);
5726     PetscValidHeaderSpecific(**submat,MAT_COOKIE,6);
5727   }
5728   if (!mat->ops->getsubmatrices) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
5729   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
5730   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
5731   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5732 
5733   ierr = PetscLogEventBegin(MAT_GetSubMatrices,mat,0,0,0);CHKERRQ(ierr);
5734   ierr = (*mat->ops->getsubmatrices)(mat,n,irow,icol,scall,submat);CHKERRQ(ierr);
5735   ierr = PetscLogEventEnd(MAT_GetSubMatrices,mat,0,0,0);CHKERRQ(ierr);
5736   for (i=0; i<n; i++) {
5737     if (mat->symmetric || mat->structurally_symmetric || mat->hermitian) {
5738       ierr = ISEqual(irow[i],icol[i],&eq);CHKERRQ(ierr);
5739       if (eq) {
5740 	if (mat->symmetric){
5741 	  ierr = MatSetOption((*submat)[i],MAT_SYMMETRIC,PETSC_TRUE);CHKERRQ(ierr);
5742 	} else if (mat->hermitian) {
5743 	  ierr = MatSetOption((*submat)[i],MAT_HERMITIAN,PETSC_TRUE);CHKERRQ(ierr);
5744 	} else if (mat->structurally_symmetric) {
5745 	  ierr = MatSetOption((*submat)[i],MAT_STRUCTURALLY_SYMMETRIC,PETSC_TRUE);CHKERRQ(ierr);
5746 	}
5747       }
5748     }
5749   }
5750   PetscFunctionReturn(0);
5751 }
5752 
5753 #undef __FUNCT__
5754 #define __FUNCT__ "MatDestroyMatrices"
5755 /*@C
5756    MatDestroyMatrices - Destroys a set of matrices obtained with MatGetSubMatrices().
5757 
5758    Collective on Mat
5759 
5760    Input Parameters:
5761 +  n - the number of local matrices
5762 -  mat - the matrices (note that this is a pointer to the array of matrices, just to match the calling
5763                        sequence of MatGetSubMatrices())
5764 
5765    Level: advanced
5766 
5767     Notes: Frees not only the matrices, but also the array that contains the matrices
5768            In Fortran will not free the array.
5769 
5770 .seealso: MatGetSubMatrices()
5771 @*/
5772 PetscErrorCode PETSCMAT_DLLEXPORT MatDestroyMatrices(PetscInt n,Mat *mat[])
5773 {
5774   PetscErrorCode ierr;
5775   PetscInt       i;
5776 
5777   PetscFunctionBegin;
5778   if (n < 0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Trying to destroy negative number of matrices %D",n);
5779   PetscValidPointer(mat,2);
5780   for (i=0; i<n; i++) {
5781     ierr = MatDestroy((*mat)[i]);CHKERRQ(ierr);
5782   }
5783   /* memory is allocated even if n = 0 */
5784   ierr = PetscFree(*mat);CHKERRQ(ierr);
5785   PetscFunctionReturn(0);
5786 }
5787 
5788 #undef __FUNCT__
5789 #define __FUNCT__ "MatGetSeqNonzeroStructure"
5790 /*@C
5791    MatGetSeqNonzeroStructure - Extracts the sequential nonzero structure from a matrix.
5792 
5793    Collective on Mat
5794 
5795    Input Parameters:
5796 .  mat - the matrix
5797 
5798    Output Parameter:
5799 .  matstruct - the sequential matrix with the nonzero structure of mat
5800 
5801   Level: intermediate
5802 
5803 .seealso: MatDestroySeqNonzeroStructure(), MatGetSubMatrices(), MatDestroyMatrices()
5804 @*/
5805 PetscErrorCode PETSCMAT_DLLEXPORT MatGetSeqNonzeroStructure(Mat mat,Mat *matstruct)
5806 {
5807   PetscErrorCode ierr;
5808 
5809   PetscFunctionBegin;
5810   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5811   PetscValidPointer(matstruct,2);
5812 
5813   PetscValidType(mat,1);
5814   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
5815   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5816 
5817   if (!mat->ops->getseqnonzerostructure) SETERRQ1(PETSC_ERR_SUP,"Not for matrix type %s\n",((PetscObject)mat)->type_name);
5818   ierr = PetscLogEventBegin(MAT_GetSeqNonzeroStructure,mat,0,0,0);CHKERRQ(ierr);
5819   ierr = (*mat->ops->getseqnonzerostructure)(mat,matstruct);CHKERRQ(ierr);
5820   ierr = PetscLogEventEnd(MAT_GetSeqNonzeroStructure,mat,0,0,0);CHKERRQ(ierr);
5821   PetscFunctionReturn(0);
5822 }
5823 
5824 #undef __FUNCT__
5825 #define __FUNCT__ "MatDestroySeqNonzeroStructure"
5826 /*@C
5827    MatDestroySeqNonzeroStructure - Destroys matrix obtained with MatGetSeqNonzeroStructure().
5828 
5829    Collective on Mat
5830 
5831    Input Parameters:
5832 .  mat - the matrix (note that this is a pointer to the array of matrices, just to match the calling
5833                        sequence of MatGetSequentialNonzeroStructure())
5834 
5835    Level: advanced
5836 
5837     Notes: Frees not only the matrices, but also the array that contains the matrices
5838 
5839 .seealso: MatGetSeqNonzeroStructure()
5840 @*/
5841 PetscErrorCode PETSCMAT_DLLEXPORT MatDestroySeqNonzeroStructure(Mat *mat)
5842 {
5843   PetscErrorCode ierr;
5844 
5845   PetscFunctionBegin;
5846   PetscValidPointer(mat,1);
5847   ierr = MatDestroy(*mat);CHKERRQ(ierr);
5848   PetscFunctionReturn(0);
5849 }
5850 
5851 #undef __FUNCT__
5852 #define __FUNCT__ "MatIncreaseOverlap"
5853 /*@
5854    MatIncreaseOverlap - Given a set of submatrices indicated by index sets,
5855    replaces the index sets by larger ones that represent submatrices with
5856    additional overlap.
5857 
5858    Collective on Mat
5859 
5860    Input Parameters:
5861 +  mat - the matrix
5862 .  n   - the number of index sets
5863 .  is  - the array of index sets (these index sets will changed during the call)
5864 -  ov  - the additional overlap requested
5865 
5866    Level: developer
5867 
5868    Concepts: overlap
5869    Concepts: ASM^computing overlap
5870 
5871 .seealso: MatGetSubMatrices()
5872 @*/
5873 PetscErrorCode PETSCMAT_DLLEXPORT MatIncreaseOverlap(Mat mat,PetscInt n,IS is[],PetscInt ov)
5874 {
5875   PetscErrorCode ierr;
5876 
5877   PetscFunctionBegin;
5878   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5879   PetscValidType(mat,1);
5880   if (n < 0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Must have one or more domains, you have %D",n);
5881   if (n) {
5882     PetscValidPointer(is,3);
5883     PetscValidHeaderSpecific(*is,IS_COOKIE,3);
5884   }
5885   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
5886   if (mat->factor)     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
5887   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5888 
5889   if (!ov) PetscFunctionReturn(0);
5890   if (!mat->ops->increaseoverlap) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
5891   ierr = PetscLogEventBegin(MAT_IncreaseOverlap,mat,0,0,0);CHKERRQ(ierr);
5892   ierr = (*mat->ops->increaseoverlap)(mat,n,is,ov);CHKERRQ(ierr);
5893   ierr = PetscLogEventEnd(MAT_IncreaseOverlap,mat,0,0,0);CHKERRQ(ierr);
5894   PetscFunctionReturn(0);
5895 }
5896 
5897 #undef __FUNCT__
5898 #define __FUNCT__ "MatGetBlockSize"
5899 /*@
5900    MatGetBlockSize - Returns the matrix block size; useful especially for the
5901    block row and block diagonal formats.
5902 
5903    Not Collective
5904 
5905    Input Parameter:
5906 .  mat - the matrix
5907 
5908    Output Parameter:
5909 .  bs - block size
5910 
5911    Notes:
5912    Block row formats are MATSEQBAIJ, MATMPIBAIJ, MATSEQSBAIJ, MATMPISBAIJ
5913 
5914    Level: intermediate
5915 
5916    Concepts: matrices^block size
5917 
5918 .seealso: MatCreateSeqBAIJ(), MatCreateMPIBAIJ()
5919 @*/
5920 PetscErrorCode PETSCMAT_DLLEXPORT MatGetBlockSize(Mat mat,PetscInt *bs)
5921 {
5922   PetscErrorCode ierr;
5923 
5924   PetscFunctionBegin;
5925   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5926   PetscValidType(mat,1);
5927   PetscValidIntPointer(bs,2);
5928   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5929   *bs = mat->rmap->bs;
5930   PetscFunctionReturn(0);
5931 }
5932 
5933 #undef __FUNCT__
5934 #define __FUNCT__ "MatSetBlockSize"
5935 /*@
5936    MatSetBlockSize - Sets the matrix block size; for many matrix types you
5937      cannot use this and MUST set the blocksize when you preallocate the matrix
5938 
5939    Collective on Mat
5940 
5941    Input Parameters:
5942 +  mat - the matrix
5943 -  bs - block size
5944 
5945    Notes:
5946      Only works for shell and AIJ matrices
5947 
5948    Level: intermediate
5949 
5950    Concepts: matrices^block size
5951 
5952 .seealso: MatCreateSeqBAIJ(), MatCreateMPIBAIJ(), MatGetBlockSize()
5953 @*/
5954 PetscErrorCode PETSCMAT_DLLEXPORT MatSetBlockSize(Mat mat,PetscInt bs)
5955 {
5956   PetscErrorCode ierr;
5957 
5958   PetscFunctionBegin;
5959   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5960   PetscValidType(mat,1);
5961   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5962   if (mat->ops->setblocksize) {
5963     /* XXX should check if (bs < 1) ??? */
5964     ierr = PetscMapSetBlockSize(mat->rmap,bs);CHKERRQ(ierr);
5965     ierr = PetscMapSetBlockSize(mat->cmap,bs);CHKERRQ(ierr);
5966     ierr = (*mat->ops->setblocksize)(mat,bs);CHKERRQ(ierr);
5967   } else {
5968     SETERRQ1(PETSC_ERR_ARG_INCOMP,"Cannot set the blocksize for matrix type %s",((PetscObject)mat)->type_name);
5969   }
5970   PetscFunctionReturn(0);
5971 }
5972 
5973 #undef __FUNCT__
5974 #define __FUNCT__ "MatGetRowIJ"
5975 /*@C
5976     MatGetRowIJ - Returns the compressed row storage i and j indices for sequential matrices.
5977 
5978    Collective on Mat
5979 
5980     Input Parameters:
5981 +   mat - the matrix
5982 .   shift -  0 or 1 indicating we want the indices starting at 0 or 1
5983 .   symmetric - PETSC_TRUE or PETSC_FALSE indicating the matrix data structure should be
5984                 symmetrized
5985 -   inodecompressed - PETSC_TRUE or PETSC_FALSE  indicating if the nonzero structure of the
5986                  inodes or the nonzero elements is wanted. For BAIJ matrices the compressed version is
5987                  always used.
5988 
5989     Output Parameters:
5990 +   n - number of rows in the (possibly compressed) matrix
5991 .   ia - the row pointers [of length n+1]
5992 .   ja - the column indices
5993 -   done - indicates if the routine actually worked and returned appropriate ia[] and ja[] arrays; callers
5994            are responsible for handling the case when done == PETSC_FALSE and ia and ja are not set
5995 
5996     Level: developer
5997 
5998     Notes: You CANNOT change any of the ia[] or ja[] values.
5999 
6000            Use MatRestoreRowIJ() when you are finished accessing the ia[] and ja[] values
6001 
6002     Fortran Node
6003 
6004            In Fortran use
6005 $           PetscInt ia(1), ja(1)
6006 $           PetscOffset iia, jja
6007 $      call MatGetRowIJ(mat,shift,symmetric,inodecompressed,n,ia,iia,ja,jja,done,ierr)
6008 
6009        Acess the ith and jth entries via ia(iia + i) and ja(jja + j)
6010 
6011 .seealso: MatGetColumnIJ(), MatRestoreRowIJ(), MatGetArray()
6012 @*/
6013 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRowIJ(Mat mat,PetscInt shift,PetscTruth symmetric,PetscTruth inodecompressed,PetscInt *n,PetscInt *ia[],PetscInt* ja[],PetscTruth *done)
6014 {
6015   PetscErrorCode ierr;
6016 
6017   PetscFunctionBegin;
6018   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6019   PetscValidType(mat,1);
6020   PetscValidIntPointer(n,4);
6021   if (ia) PetscValidIntPointer(ia,5);
6022   if (ja) PetscValidIntPointer(ja,6);
6023   PetscValidIntPointer(done,7);
6024   ierr = MatPreallocated(mat);CHKERRQ(ierr);
6025   if (!mat->ops->getrowij) *done = PETSC_FALSE;
6026   else {
6027     *done = PETSC_TRUE;
6028     ierr = PetscLogEventBegin(MAT_GetRowIJ,mat,0,0,0);CHKERRQ(ierr);
6029     ierr  = (*mat->ops->getrowij)(mat,shift,symmetric,inodecompressed,n,ia,ja,done);CHKERRQ(ierr);
6030     ierr = PetscLogEventEnd(MAT_GetRowIJ,mat,0,0,0);CHKERRQ(ierr);
6031   }
6032   PetscFunctionReturn(0);
6033 }
6034 
6035 #undef __FUNCT__
6036 #define __FUNCT__ "MatGetColumnIJ"
6037 /*@C
6038     MatGetColumnIJ - Returns the compressed column storage i and j indices for sequential matrices.
6039 
6040     Collective on Mat
6041 
6042     Input Parameters:
6043 +   mat - the matrix
6044 .   shift - 1 or zero indicating we want the indices starting at 0 or 1
6045 .   symmetric - PETSC_TRUE or PETSC_FALSE indicating the matrix data structure should be
6046                 symmetrized
6047 -   inodecompressed - PETSC_TRUE or PETSC_FALSE indicating if the nonzero structure of the
6048                  inodes or the nonzero elements is wanted. For BAIJ matrices the compressed version is
6049                  always used.
6050 
6051     Output Parameters:
6052 +   n - number of columns in the (possibly compressed) matrix
6053 .   ia - the column pointers
6054 .   ja - the row indices
6055 -   done - PETSC_TRUE or PETSC_FALSE, indicating whether the values have been returned
6056 
6057     Level: developer
6058 
6059 .seealso: MatGetRowIJ(), MatRestoreColumnIJ()
6060 @*/
6061 PetscErrorCode PETSCMAT_DLLEXPORT MatGetColumnIJ(Mat mat,PetscInt shift,PetscTruth symmetric,PetscTruth inodecompressed,PetscInt *n,PetscInt *ia[],PetscInt* ja[],PetscTruth *done)
6062 {
6063   PetscErrorCode ierr;
6064 
6065   PetscFunctionBegin;
6066   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6067   PetscValidType(mat,1);
6068   PetscValidIntPointer(n,4);
6069   if (ia) PetscValidIntPointer(ia,5);
6070   if (ja) PetscValidIntPointer(ja,6);
6071   PetscValidIntPointer(done,7);
6072   ierr = MatPreallocated(mat);CHKERRQ(ierr);
6073   if (!mat->ops->getcolumnij) *done = PETSC_FALSE;
6074   else {
6075     *done = PETSC_TRUE;
6076     ierr  = (*mat->ops->getcolumnij)(mat,shift,symmetric,inodecompressed,n,ia,ja,done);CHKERRQ(ierr);
6077   }
6078   PetscFunctionReturn(0);
6079 }
6080 
6081 #undef __FUNCT__
6082 #define __FUNCT__ "MatRestoreRowIJ"
6083 /*@C
6084     MatRestoreRowIJ - Call after you are completed with the ia,ja indices obtained with
6085     MatGetRowIJ().
6086 
6087     Collective on Mat
6088 
6089     Input Parameters:
6090 +   mat - the matrix
6091 .   shift - 1 or zero indicating we want the indices starting at 0 or 1
6092 .   symmetric - PETSC_TRUE or PETSC_FALSE indicating the matrix data structure should be
6093                 symmetrized
6094 -   inodecompressed -  PETSC_TRUE or PETSC_FALSE indicating if the nonzero structure of the
6095                  inodes or the nonzero elements is wanted. For BAIJ matrices the compressed version is
6096                  always used.
6097 
6098     Output Parameters:
6099 +   n - size of (possibly compressed) matrix
6100 .   ia - the row pointers
6101 .   ja - the column indices
6102 -   done - PETSC_TRUE or PETSC_FALSE indicated that the values have been returned
6103 
6104     Level: developer
6105 
6106 .seealso: MatGetRowIJ(), MatRestoreColumnIJ()
6107 @*/
6108 PetscErrorCode PETSCMAT_DLLEXPORT MatRestoreRowIJ(Mat mat,PetscInt shift,PetscTruth symmetric,PetscTruth inodecompressed,PetscInt *n,PetscInt *ia[],PetscInt* ja[],PetscTruth *done)
6109 {
6110   PetscErrorCode ierr;
6111 
6112   PetscFunctionBegin;
6113   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6114   PetscValidType(mat,1);
6115   if (ia) PetscValidIntPointer(ia,5);
6116   if (ja) PetscValidIntPointer(ja,6);
6117   PetscValidIntPointer(done,7);
6118   ierr = MatPreallocated(mat);CHKERRQ(ierr);
6119 
6120   if (!mat->ops->restorerowij) *done = PETSC_FALSE;
6121   else {
6122     *done = PETSC_TRUE;
6123     ierr  = (*mat->ops->restorerowij)(mat,shift,symmetric,inodecompressed,n,ia,ja,done);CHKERRQ(ierr);
6124   }
6125   PetscFunctionReturn(0);
6126 }
6127 
6128 #undef __FUNCT__
6129 #define __FUNCT__ "MatRestoreColumnIJ"
6130 /*@C
6131     MatRestoreColumnIJ - Call after you are completed with the ia,ja indices obtained with
6132     MatGetColumnIJ().
6133 
6134     Collective on Mat
6135 
6136     Input Parameters:
6137 +   mat - the matrix
6138 .   shift - 1 or zero indicating we want the indices starting at 0 or 1
6139 -   symmetric - PETSC_TRUE or PETSC_FALSE indicating the matrix data structure should be
6140                 symmetrized
6141 -   inodecompressed - PETSC_TRUE or PETSC_FALSE indicating if the nonzero structure of the
6142                  inodes or the nonzero elements is wanted. For BAIJ matrices the compressed version is
6143                  always used.
6144 
6145     Output Parameters:
6146 +   n - size of (possibly compressed) matrix
6147 .   ia - the column pointers
6148 .   ja - the row indices
6149 -   done - PETSC_TRUE or PETSC_FALSE indicated that the values have been returned
6150 
6151     Level: developer
6152 
6153 .seealso: MatGetColumnIJ(), MatRestoreRowIJ()
6154 @*/
6155 PetscErrorCode PETSCMAT_DLLEXPORT MatRestoreColumnIJ(Mat mat,PetscInt shift,PetscTruth symmetric,PetscTruth inodecompressed,PetscInt *n,PetscInt *ia[],PetscInt* ja[],PetscTruth *done)
6156 {
6157   PetscErrorCode ierr;
6158 
6159   PetscFunctionBegin;
6160   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6161   PetscValidType(mat,1);
6162   if (ia) PetscValidIntPointer(ia,5);
6163   if (ja) PetscValidIntPointer(ja,6);
6164   PetscValidIntPointer(done,7);
6165   ierr = MatPreallocated(mat);CHKERRQ(ierr);
6166 
6167   if (!mat->ops->restorecolumnij) *done = PETSC_FALSE;
6168   else {
6169     *done = PETSC_TRUE;
6170     ierr  = (*mat->ops->restorecolumnij)(mat,shift,symmetric,inodecompressed,n,ia,ja,done);CHKERRQ(ierr);
6171   }
6172   PetscFunctionReturn(0);
6173 }
6174 
6175 #undef __FUNCT__
6176 #define __FUNCT__ "MatColoringPatch"
6177 /*@C
6178     MatColoringPatch -Used inside matrix coloring routines that
6179     use MatGetRowIJ() and/or MatGetColumnIJ().
6180 
6181     Collective on Mat
6182 
6183     Input Parameters:
6184 +   mat - the matrix
6185 .   ncolors - max color value
6186 .   n   - number of entries in colorarray
6187 -   colorarray - array indicating color for each column
6188 
6189     Output Parameters:
6190 .   iscoloring - coloring generated using colorarray information
6191 
6192     Level: developer
6193 
6194 .seealso: MatGetRowIJ(), MatGetColumnIJ()
6195 
6196 @*/
6197 PetscErrorCode PETSCMAT_DLLEXPORT MatColoringPatch(Mat mat,PetscInt ncolors,PetscInt n,ISColoringValue colorarray[],ISColoring *iscoloring)
6198 {
6199   PetscErrorCode ierr;
6200 
6201   PetscFunctionBegin;
6202   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6203   PetscValidType(mat,1);
6204   PetscValidIntPointer(colorarray,4);
6205   PetscValidPointer(iscoloring,5);
6206   ierr = MatPreallocated(mat);CHKERRQ(ierr);
6207 
6208   if (!mat->ops->coloringpatch){
6209     ierr = ISColoringCreate(((PetscObject)mat)->comm,ncolors,n,colorarray,iscoloring);CHKERRQ(ierr);
6210   } else {
6211     ierr = (*mat->ops->coloringpatch)(mat,ncolors,n,colorarray,iscoloring);CHKERRQ(ierr);
6212   }
6213   PetscFunctionReturn(0);
6214 }
6215 
6216 
6217 #undef __FUNCT__
6218 #define __FUNCT__ "MatSetUnfactored"
6219 /*@
6220    MatSetUnfactored - Resets a factored matrix to be treated as unfactored.
6221 
6222    Collective on Mat
6223 
6224    Input Parameter:
6225 .  mat - the factored matrix to be reset
6226 
6227    Notes:
6228    This routine should be used only with factored matrices formed by in-place
6229    factorization via ILU(0) (or by in-place LU factorization for the MATSEQDENSE
6230    format).  This option can save memory, for example, when solving nonlinear
6231    systems with a matrix-free Newton-Krylov method and a matrix-based, in-place
6232    ILU(0) preconditioner.
6233 
6234    Note that one can specify in-place ILU(0) factorization by calling
6235 .vb
6236      PCType(pc,PCILU);
6237      PCFactorSeUseInPlace(pc);
6238 .ve
6239    or by using the options -pc_type ilu -pc_factor_in_place
6240 
6241    In-place factorization ILU(0) can also be used as a local
6242    solver for the blocks within the block Jacobi or additive Schwarz
6243    methods (runtime option: -sub_pc_factor_in_place).  See the discussion
6244    of these preconditioners in the users manual for details on setting
6245    local solver options.
6246 
6247    Most users should employ the simplified KSP interface for linear solvers
6248    instead of working directly with matrix algebra routines such as this.
6249    See, e.g., KSPCreate().
6250 
6251    Level: developer
6252 
6253 .seealso: PCFactorSetUseInPlace()
6254 
6255    Concepts: matrices^unfactored
6256 
6257 @*/
6258 PetscErrorCode PETSCMAT_DLLEXPORT MatSetUnfactored(Mat mat)
6259 {
6260   PetscErrorCode ierr;
6261 
6262   PetscFunctionBegin;
6263   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6264   PetscValidType(mat,1);
6265   ierr = MatPreallocated(mat);CHKERRQ(ierr);
6266   mat->factor = MAT_FACTOR_NONE;
6267   if (!mat->ops->setunfactored) PetscFunctionReturn(0);
6268   ierr = (*mat->ops->setunfactored)(mat);CHKERRQ(ierr);
6269   PetscFunctionReturn(0);
6270 }
6271 
6272 /*MC
6273     MatGetArrayF90 - Accesses a matrix array from Fortran90.
6274 
6275     Synopsis:
6276     MatGetArrayF90(Mat x,{Scalar, pointer :: xx_v(:)},integer ierr)
6277 
6278     Not collective
6279 
6280     Input Parameter:
6281 .   x - matrix
6282 
6283     Output Parameters:
6284 +   xx_v - the Fortran90 pointer to the array
6285 -   ierr - error code
6286 
6287     Example of Usage:
6288 .vb
6289       PetscScalar, pointer xx_v(:)
6290       ....
6291       call MatGetArrayF90(x,xx_v,ierr)
6292       a = xx_v(3)
6293       call MatRestoreArrayF90(x,xx_v,ierr)
6294 .ve
6295 
6296     Notes:
6297     Not yet supported for all F90 compilers
6298 
6299     Level: advanced
6300 
6301 .seealso:  MatRestoreArrayF90(), MatGetArray(), MatRestoreArray()
6302 
6303     Concepts: matrices^accessing array
6304 
6305 M*/
6306 
6307 /*MC
6308     MatRestoreArrayF90 - Restores a matrix array that has been
6309     accessed with MatGetArrayF90().
6310 
6311     Synopsis:
6312     MatRestoreArrayF90(Mat x,{Scalar, pointer :: xx_v(:)},integer ierr)
6313 
6314     Not collective
6315 
6316     Input Parameters:
6317 +   x - matrix
6318 -   xx_v - the Fortran90 pointer to the array
6319 
6320     Output Parameter:
6321 .   ierr - error code
6322 
6323     Example of Usage:
6324 .vb
6325        PetscScalar, pointer xx_v(:)
6326        ....
6327        call MatGetArrayF90(x,xx_v,ierr)
6328        a = xx_v(3)
6329        call MatRestoreArrayF90(x,xx_v,ierr)
6330 .ve
6331 
6332     Notes:
6333     Not yet supported for all F90 compilers
6334 
6335     Level: advanced
6336 
6337 .seealso:  MatGetArrayF90(), MatGetArray(), MatRestoreArray()
6338 
6339 M*/
6340 
6341 
6342 #undef __FUNCT__
6343 #define __FUNCT__ "MatGetSubMatrix"
6344 /*@
6345     MatGetSubMatrix - Gets a single submatrix on the same number of processors
6346                       as the original matrix.
6347 
6348     Collective on Mat
6349 
6350     Input Parameters:
6351 +   mat - the original matrix
6352 .   isrow - parallel IS containing the rows this processor should obtain
6353 .   iscol - parallel IS containing all columns you wish to keep
6354 -   cll - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
6355 
6356     Output Parameter:
6357 .   newmat - the new submatrix, of the same type as the old
6358 
6359     Level: advanced
6360 
6361     Notes:
6362     The submatrix will be able to be multiplied with vectors using the same layout as iscol.
6363 
6364     The rows is isrow will be sorted into the same order as the original matrix.
6365 
6366       The first time this is called you should use a cll of MAT_INITIAL_MATRIX,
6367    the MatGetSubMatrix() routine will create the newmat for you. Any additional calls
6368    to this routine with a mat of the same nonzero structure and with a call of MAT_REUSE_MATRIX
6369    will reuse the matrix generated the first time.  You should call MatDestroy() on newmat when
6370    you are finished using it.
6371 
6372     The communicator of the newly obtained matrix is ALWAYS the same as the communicator of
6373     the input matrix.
6374 
6375     If iscol is PETSC_NULL then all columns are obtained (not supported in Fortran).
6376 
6377    Example usage:
6378    Consider the following 8x8 matrix with 34 non-zero values, that is
6379    assembled across 3 processors. Lets assume that proc0 owns 3 rows,
6380    proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
6381    as follows:
6382 
6383 .vb
6384             1  2  0  |  0  3  0  |  0  4
6385     Proc0   0  5  6  |  7  0  0  |  8  0
6386             9  0 10  | 11  0  0  | 12  0
6387     -------------------------------------
6388            13  0 14  | 15 16 17  |  0  0
6389     Proc1   0 18  0  | 19 20 21  |  0  0
6390             0  0  0  | 22 23  0  | 24  0
6391     -------------------------------------
6392     Proc2  25 26 27  |  0  0 28  | 29  0
6393            30  0  0  | 31 32 33  |  0 34
6394 .ve
6395 
6396     Suppose isrow = [0 1 | 4 | 5 6] and iscol = [1 2 | 3 4 5 | 6].  The resulting submatrix is
6397 
6398 .vb
6399             2  0  |  0  3  0  |  0
6400     Proc0   5  6  |  7  0  0  |  8
6401     -------------------------------
6402     Proc1  18  0  | 19 20 21  |  0
6403     -------------------------------
6404     Proc2  26 27  |  0  0 28  | 29
6405             0  0  | 31 32 33  |  0
6406 .ve
6407 
6408 
6409     Concepts: matrices^submatrices
6410 
6411 .seealso: MatGetSubMatrices()
6412 @*/
6413 PetscErrorCode PETSCMAT_DLLEXPORT MatGetSubMatrix(Mat mat,IS isrow,IS iscol,MatReuse cll,Mat *newmat)
6414 {
6415   PetscErrorCode ierr;
6416   PetscMPIInt    size;
6417   Mat            *local;
6418   IS             iscoltmp;
6419 
6420   PetscFunctionBegin;
6421   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6422   PetscValidHeaderSpecific(isrow,IS_COOKIE,2);
6423   if (iscol) PetscValidHeaderSpecific(iscol,IS_COOKIE,3);
6424   PetscValidPointer(newmat,6);
6425   if (cll == MAT_REUSE_MATRIX) PetscValidHeaderSpecific(*newmat,MAT_COOKIE,6);
6426   PetscValidType(mat,1);
6427   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
6428   ierr = MatPreallocated(mat);CHKERRQ(ierr);
6429   ierr = MPI_Comm_size(((PetscObject)mat)->comm,&size);CHKERRQ(ierr);
6430 
6431   if (!iscol) {
6432     ierr = ISCreateStride(((PetscObject)mat)->comm,mat->cmap->n,mat->cmap->rstart,1,&iscoltmp);CHKERRQ(ierr);
6433   } else {
6434     iscoltmp = iscol;
6435   }
6436 
6437   /* if original matrix is on just one processor then use submatrix generated */
6438   if (mat->ops->getsubmatrices && !mat->ops->getsubmatrix && size == 1 && cll == MAT_REUSE_MATRIX) {
6439     ierr = MatGetSubMatrices(mat,1,&isrow,&iscoltmp,MAT_REUSE_MATRIX,&newmat);CHKERRQ(ierr);
6440     if (!iscol) {ierr = ISDestroy(iscoltmp);CHKERRQ(ierr);}
6441     PetscFunctionReturn(0);
6442   } else if (mat->ops->getsubmatrices && !mat->ops->getsubmatrix && size == 1) {
6443     ierr    = MatGetSubMatrices(mat,1,&isrow,&iscoltmp,MAT_INITIAL_MATRIX,&local);CHKERRQ(ierr);
6444     *newmat = *local;
6445     ierr    = PetscFree(local);CHKERRQ(ierr);
6446     if (!iscol) {ierr = ISDestroy(iscoltmp);CHKERRQ(ierr);}
6447     PetscFunctionReturn(0);
6448   } else if (!mat->ops->getsubmatrix) {
6449     /* Create a new matrix type that implements the operation using the full matrix */
6450     switch (cll) {
6451       case MAT_INITIAL_MATRIX:
6452         ierr = MatCreateSubMatrix(mat,isrow,iscoltmp,newmat);CHKERRQ(ierr);
6453         break;
6454       case MAT_REUSE_MATRIX:
6455         ierr = MatSubMatrixUpdate(*newmat,mat,isrow,iscoltmp);CHKERRQ(ierr);
6456         break;
6457       default: SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Invalid MatReuse, must be either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX");
6458     }
6459     if (!iscol) {ierr = ISDestroy(iscoltmp);CHKERRQ(ierr);}
6460     PetscFunctionReturn(0);
6461   }
6462 
6463   if (!mat->ops->getsubmatrix) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
6464   ierr = (*mat->ops->getsubmatrix)(mat,isrow,iscoltmp,cll,newmat);CHKERRQ(ierr);
6465   if (!iscol) {ierr = ISDestroy(iscoltmp);CHKERRQ(ierr);}
6466   ierr = PetscObjectStateIncrease((PetscObject)*newmat);CHKERRQ(ierr);
6467   PetscFunctionReturn(0);
6468 }
6469 
6470 #undef __FUNCT__
6471 #define __FUNCT__ "MatStashSetInitialSize"
6472 /*@
6473    MatStashSetInitialSize - sets the sizes of the matrix stash, that is
6474    used during the assembly process to store values that belong to
6475    other processors.
6476 
6477    Not Collective
6478 
6479    Input Parameters:
6480 +  mat   - the matrix
6481 .  size  - the initial size of the stash.
6482 -  bsize - the initial size of the block-stash(if used).
6483 
6484    Options Database Keys:
6485 +   -matstash_initial_size <size> or <size0,size1,...sizep-1>
6486 -   -matstash_block_initial_size <bsize>  or <bsize0,bsize1,...bsizep-1>
6487 
6488    Level: intermediate
6489 
6490    Notes:
6491      The block-stash is used for values set with MatSetValuesBlocked() while
6492      the stash is used for values set with MatSetValues()
6493 
6494      Run with the option -info and look for output of the form
6495      MatAssemblyBegin_MPIXXX:Stash has MM entries, uses nn mallocs.
6496      to determine the appropriate value, MM, to use for size and
6497      MatAssemblyBegin_MPIXXX:Block-Stash has BMM entries, uses nn mallocs.
6498      to determine the value, BMM to use for bsize
6499 
6500    Concepts: stash^setting matrix size
6501    Concepts: matrices^stash
6502 
6503 .seealso: MatAssemblyBegin(), MatAssemblyEnd(), Mat, MatStashGetInfo()
6504 
6505 @*/
6506 PetscErrorCode PETSCMAT_DLLEXPORT MatStashSetInitialSize(Mat mat,PetscInt size, PetscInt bsize)
6507 {
6508   PetscErrorCode ierr;
6509 
6510   PetscFunctionBegin;
6511   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6512   PetscValidType(mat,1);
6513   ierr = MatStashSetInitialSize_Private(&mat->stash,size);CHKERRQ(ierr);
6514   ierr = MatStashSetInitialSize_Private(&mat->bstash,bsize);CHKERRQ(ierr);
6515   PetscFunctionReturn(0);
6516 }
6517 
6518 #undef __FUNCT__
6519 #define __FUNCT__ "MatInterpolateAdd"
6520 /*@
6521    MatInterpolateAdd - w = y + A*x or A'*x depending on the shape of
6522      the matrix
6523 
6524    Collective on Mat
6525 
6526    Input Parameters:
6527 +  mat   - the matrix
6528 .  x,y - the vectors
6529 -  w - where the result is stored
6530 
6531    Level: intermediate
6532 
6533    Notes:
6534     w may be the same vector as y.
6535 
6536     This allows one to use either the restriction or interpolation (its transpose)
6537     matrix to do the interpolation
6538 
6539     Concepts: interpolation
6540 
6541 .seealso: MatMultAdd(), MatMultTransposeAdd(), MatRestrict()
6542 
6543 @*/
6544 PetscErrorCode PETSCMAT_DLLEXPORT MatInterpolateAdd(Mat A,Vec x,Vec y,Vec w)
6545 {
6546   PetscErrorCode ierr;
6547   PetscInt       M,N;
6548 
6549   PetscFunctionBegin;
6550   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
6551   PetscValidHeaderSpecific(x,VEC_COOKIE,2);
6552   PetscValidHeaderSpecific(y,VEC_COOKIE,3);
6553   PetscValidHeaderSpecific(w,VEC_COOKIE,4);
6554   PetscValidType(A,1);
6555   ierr = MatPreallocated(A);CHKERRQ(ierr);
6556   ierr = MatGetSize(A,&M,&N);CHKERRQ(ierr);
6557   if (N > M) {
6558     ierr = MatMultTransposeAdd(A,x,y,w);CHKERRQ(ierr);
6559   } else {
6560     ierr = MatMultAdd(A,x,y,w);CHKERRQ(ierr);
6561   }
6562   PetscFunctionReturn(0);
6563 }
6564 
6565 #undef __FUNCT__
6566 #define __FUNCT__ "MatInterpolate"
6567 /*@
6568    MatInterpolate - y = A*x or A'*x depending on the shape of
6569      the matrix
6570 
6571    Collective on Mat
6572 
6573    Input Parameters:
6574 +  mat   - the matrix
6575 -  x,y - the vectors
6576 
6577    Level: intermediate
6578 
6579    Notes:
6580     This allows one to use either the restriction or interpolation (its transpose)
6581     matrix to do the interpolation
6582 
6583    Concepts: matrices^interpolation
6584 
6585 .seealso: MatMultAdd(), MatMultTransposeAdd(), MatRestrict()
6586 
6587 @*/
6588 PetscErrorCode PETSCMAT_DLLEXPORT MatInterpolate(Mat A,Vec x,Vec y)
6589 {
6590   PetscErrorCode ierr;
6591   PetscInt       M,N;
6592 
6593   PetscFunctionBegin;
6594   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
6595   PetscValidHeaderSpecific(x,VEC_COOKIE,2);
6596   PetscValidHeaderSpecific(y,VEC_COOKIE,3);
6597   PetscValidType(A,1);
6598   ierr = MatPreallocated(A);CHKERRQ(ierr);
6599   ierr = MatGetSize(A,&M,&N);CHKERRQ(ierr);
6600   if (N > M) {
6601     ierr = MatMultTranspose(A,x,y);CHKERRQ(ierr);
6602   } else {
6603     ierr = MatMult(A,x,y);CHKERRQ(ierr);
6604   }
6605   PetscFunctionReturn(0);
6606 }
6607 
6608 #undef __FUNCT__
6609 #define __FUNCT__ "MatRestrict"
6610 /*@
6611    MatRestrict - y = A*x or A'*x
6612 
6613    Collective on Mat
6614 
6615    Input Parameters:
6616 +  mat   - the matrix
6617 -  x,y - the vectors
6618 
6619    Level: intermediate
6620 
6621    Notes:
6622     This allows one to use either the restriction or interpolation (its transpose)
6623     matrix to do the restriction
6624 
6625    Concepts: matrices^restriction
6626 
6627 .seealso: MatMultAdd(), MatMultTransposeAdd(), MatInterpolate()
6628 
6629 @*/
6630 PetscErrorCode PETSCMAT_DLLEXPORT MatRestrict(Mat A,Vec x,Vec y)
6631 {
6632   PetscErrorCode ierr;
6633   PetscInt       M,N;
6634 
6635   PetscFunctionBegin;
6636   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
6637   PetscValidHeaderSpecific(x,VEC_COOKIE,2);
6638   PetscValidHeaderSpecific(y,VEC_COOKIE,3);
6639   PetscValidType(A,1);
6640   ierr = MatPreallocated(A);CHKERRQ(ierr);
6641 
6642   ierr = MatGetSize(A,&M,&N);CHKERRQ(ierr);
6643   if (N > M) {
6644     ierr = MatMult(A,x,y);CHKERRQ(ierr);
6645   } else {
6646     ierr = MatMultTranspose(A,x,y);CHKERRQ(ierr);
6647   }
6648   PetscFunctionReturn(0);
6649 }
6650 
6651 #undef __FUNCT__
6652 #define __FUNCT__ "MatNullSpaceAttach"
6653 /*@
6654    MatNullSpaceAttach - attaches a null space to a matrix.
6655         This null space will be removed from the resulting vector whenever
6656         MatMult() is called
6657 
6658    Collective on Mat
6659 
6660    Input Parameters:
6661 +  mat - the matrix
6662 -  nullsp - the null space object
6663 
6664    Level: developer
6665 
6666    Notes:
6667       Overwrites any previous null space that may have been attached
6668 
6669    Concepts: null space^attaching to matrix
6670 
6671 .seealso: MatCreate(), MatNullSpaceCreate()
6672 @*/
6673 PetscErrorCode PETSCMAT_DLLEXPORT MatNullSpaceAttach(Mat mat,MatNullSpace nullsp)
6674 {
6675   PetscErrorCode ierr;
6676 
6677   PetscFunctionBegin;
6678   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6679   PetscValidType(mat,1);
6680   PetscValidHeaderSpecific(nullsp,MAT_NULLSPACE_COOKIE,2);
6681   ierr = MatPreallocated(mat);CHKERRQ(ierr);
6682   ierr = PetscObjectReference((PetscObject)nullsp);CHKERRQ(ierr);
6683   if (mat->nullsp) { ierr = MatNullSpaceDestroy(mat->nullsp);CHKERRQ(ierr); }
6684   mat->nullsp = nullsp;
6685   PetscFunctionReturn(0);
6686 }
6687 
6688 #undef __FUNCT__
6689 #define __FUNCT__ "MatICCFactor"
6690 /*@C
6691    MatICCFactor - Performs in-place incomplete Cholesky factorization of matrix.
6692 
6693    Collective on Mat
6694 
6695    Input Parameters:
6696 +  mat - the matrix
6697 .  row - row/column permutation
6698 .  fill - expected fill factor >= 1.0
6699 -  level - level of fill, for ICC(k)
6700 
6701    Notes:
6702    Probably really in-place only when level of fill is zero, otherwise allocates
6703    new space to store factored matrix and deletes previous memory.
6704 
6705    Most users should employ the simplified KSP interface for linear solvers
6706    instead of working directly with matrix algebra routines such as this.
6707    See, e.g., KSPCreate().
6708 
6709    Level: developer
6710 
6711    Concepts: matrices^incomplete Cholesky factorization
6712    Concepts: Cholesky factorization
6713 
6714 .seealso: MatICCFactorSymbolic(), MatLUFactorNumeric(), MatCholeskyFactor()
6715 
6716     Developer Note: fortran interface is not autogenerated as the f90
6717     interface defintion cannot be generated correctly [due to MatFactorInfo]
6718 
6719 @*/
6720 PetscErrorCode PETSCMAT_DLLEXPORT MatICCFactor(Mat mat,IS row,const MatFactorInfo* info)
6721 {
6722   PetscErrorCode ierr;
6723 
6724   PetscFunctionBegin;
6725   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6726   PetscValidType(mat,1);
6727   if (row) PetscValidHeaderSpecific(row,IS_COOKIE,2);
6728   PetscValidPointer(info,3);
6729   if (mat->rmap->N != mat->cmap->N) SETERRQ(PETSC_ERR_ARG_WRONG,"matrix must be square");
6730   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
6731   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
6732   if (!mat->ops->iccfactor) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
6733   ierr = MatPreallocated(mat);CHKERRQ(ierr);
6734   ierr = (*mat->ops->iccfactor)(mat,row,info);CHKERRQ(ierr);
6735   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
6736   PetscFunctionReturn(0);
6737 }
6738 
6739 #undef __FUNCT__
6740 #define __FUNCT__ "MatSetValuesAdic"
6741 /*@
6742    MatSetValuesAdic - Sets values computed with ADIC automatic differentiation into a matrix.
6743 
6744    Not Collective
6745 
6746    Input Parameters:
6747 +  mat - the matrix
6748 -  v - the values compute with ADIC
6749 
6750    Level: developer
6751 
6752    Notes:
6753      Must call MatSetColoring() before using this routine. Also this matrix must already
6754      have its nonzero pattern determined.
6755 
6756 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal(),
6757           MatSetValues(), MatSetColoring(), MatSetValuesAdifor()
6758 @*/
6759 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesAdic(Mat mat,void *v)
6760 {
6761   PetscErrorCode ierr;
6762 
6763   PetscFunctionBegin;
6764   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6765   PetscValidType(mat,1);
6766   PetscValidPointer(mat,2);
6767 
6768   if (!mat->assembled) {
6769     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Matrix must be already assembled");
6770   }
6771   ierr = PetscLogEventBegin(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
6772   if (!mat->ops->setvaluesadic) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
6773   ierr = (*mat->ops->setvaluesadic)(mat,v);CHKERRQ(ierr);
6774   ierr = PetscLogEventEnd(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
6775   ierr = MatView_Private(mat);CHKERRQ(ierr);
6776   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
6777   PetscFunctionReturn(0);
6778 }
6779 
6780 
6781 #undef __FUNCT__
6782 #define __FUNCT__ "MatSetColoring"
6783 /*@
6784    MatSetColoring - Sets a coloring used by calls to MatSetValuesAdic()
6785 
6786    Not Collective
6787 
6788    Input Parameters:
6789 +  mat - the matrix
6790 -  coloring - the coloring
6791 
6792    Level: developer
6793 
6794 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal(),
6795           MatSetValues(), MatSetValuesAdic()
6796 @*/
6797 PetscErrorCode PETSCMAT_DLLEXPORT MatSetColoring(Mat mat,ISColoring coloring)
6798 {
6799   PetscErrorCode ierr;
6800 
6801   PetscFunctionBegin;
6802   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6803   PetscValidType(mat,1);
6804   PetscValidPointer(coloring,2);
6805 
6806   if (!mat->assembled) {
6807     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Matrix must be already assembled");
6808   }
6809   if (!mat->ops->setcoloring) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
6810   ierr = (*mat->ops->setcoloring)(mat,coloring);CHKERRQ(ierr);
6811   PetscFunctionReturn(0);
6812 }
6813 
6814 #undef __FUNCT__
6815 #define __FUNCT__ "MatSetValuesAdifor"
6816 /*@
6817    MatSetValuesAdifor - Sets values computed with automatic differentiation into a matrix.
6818 
6819    Not Collective
6820 
6821    Input Parameters:
6822 +  mat - the matrix
6823 .  nl - leading dimension of v
6824 -  v - the values compute with ADIFOR
6825 
6826    Level: developer
6827 
6828    Notes:
6829      Must call MatSetColoring() before using this routine. Also this matrix must already
6830      have its nonzero pattern determined.
6831 
6832 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal(),
6833           MatSetValues(), MatSetColoring()
6834 @*/
6835 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesAdifor(Mat mat,PetscInt nl,void *v)
6836 {
6837   PetscErrorCode ierr;
6838 
6839   PetscFunctionBegin;
6840   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6841   PetscValidType(mat,1);
6842   PetscValidPointer(v,3);
6843 
6844   if (!mat->assembled) {
6845     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Matrix must be already assembled");
6846   }
6847   ierr = PetscLogEventBegin(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
6848   if (!mat->ops->setvaluesadifor) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
6849   ierr = (*mat->ops->setvaluesadifor)(mat,nl,v);CHKERRQ(ierr);
6850   ierr = PetscLogEventEnd(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
6851   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
6852   PetscFunctionReturn(0);
6853 }
6854 
6855 #undef __FUNCT__
6856 #define __FUNCT__ "MatDiagonalScaleLocal"
6857 /*@
6858    MatDiagonalScaleLocal - Scales columns of a matrix given the scaling values including the
6859          ghosted ones.
6860 
6861    Not Collective
6862 
6863    Input Parameters:
6864 +  mat - the matrix
6865 -  diag = the diagonal values, including ghost ones
6866 
6867    Level: developer
6868 
6869    Notes: Works only for MPIAIJ and MPIBAIJ matrices
6870 
6871 .seealso: MatDiagonalScale()
6872 @*/
6873 PetscErrorCode PETSCMAT_DLLEXPORT MatDiagonalScaleLocal(Mat mat,Vec diag)
6874 {
6875   PetscErrorCode ierr;
6876   PetscMPIInt    size;
6877 
6878   PetscFunctionBegin;
6879   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6880   PetscValidHeaderSpecific(diag,VEC_COOKIE,2);
6881   PetscValidType(mat,1);
6882 
6883   if (!mat->assembled) {
6884     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Matrix must be already assembled");
6885   }
6886   ierr = PetscLogEventBegin(MAT_Scale,mat,0,0,0);CHKERRQ(ierr);
6887   ierr = MPI_Comm_size(((PetscObject)mat)->comm,&size);CHKERRQ(ierr);
6888   if (size == 1) {
6889     PetscInt n,m;
6890     ierr = VecGetSize(diag,&n);CHKERRQ(ierr);
6891     ierr = MatGetSize(mat,0,&m);CHKERRQ(ierr);
6892     if (m == n) {
6893       ierr = MatDiagonalScale(mat,0,diag);CHKERRQ(ierr);
6894     } else {
6895       SETERRQ(PETSC_ERR_SUP,"Only supported for sequential matrices when no ghost points/periodic conditions");
6896     }
6897   } else {
6898     PetscErrorCode (*f)(Mat,Vec);
6899     ierr = PetscObjectQueryFunction((PetscObject)mat,"MatDiagonalScaleLocal_C",(void (**)(void))&f);CHKERRQ(ierr);
6900     if (f) {
6901       ierr = (*f)(mat,diag);CHKERRQ(ierr);
6902     } else {
6903       SETERRQ(PETSC_ERR_SUP,"Only supported for MPIAIJ and MPIBAIJ parallel matrices");
6904     }
6905   }
6906   ierr = PetscLogEventEnd(MAT_Scale,mat,0,0,0);CHKERRQ(ierr);
6907   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
6908   PetscFunctionReturn(0);
6909 }
6910 
6911 #undef __FUNCT__
6912 #define __FUNCT__ "MatGetInertia"
6913 /*@
6914    MatGetInertia - Gets the inertia from a factored matrix
6915 
6916    Collective on Mat
6917 
6918    Input Parameter:
6919 .  mat - the matrix
6920 
6921    Output Parameters:
6922 +   nneg - number of negative eigenvalues
6923 .   nzero - number of zero eigenvalues
6924 -   npos - number of positive eigenvalues
6925 
6926    Level: advanced
6927 
6928    Notes: Matrix must have been factored by MatCholeskyFactor()
6929 
6930 
6931 @*/
6932 PetscErrorCode PETSCMAT_DLLEXPORT MatGetInertia(Mat mat,PetscInt *nneg,PetscInt *nzero,PetscInt *npos)
6933 {
6934   PetscErrorCode ierr;
6935 
6936   PetscFunctionBegin;
6937   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6938   PetscValidType(mat,1);
6939   if (!mat->factor)    SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
6940   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Numeric factor mat is not assembled");
6941   if (!mat->ops->getinertia) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
6942   ierr = (*mat->ops->getinertia)(mat,nneg,nzero,npos);CHKERRQ(ierr);
6943   PetscFunctionReturn(0);
6944 }
6945 
6946 /* ----------------------------------------------------------------*/
6947 #undef __FUNCT__
6948 #define __FUNCT__ "MatSolves"
6949 /*@C
6950    MatSolves - Solves A x = b, given a factored matrix, for a collection of vectors
6951 
6952    Collective on Mat and Vecs
6953 
6954    Input Parameters:
6955 +  mat - the factored matrix
6956 -  b - the right-hand-side vectors
6957 
6958    Output Parameter:
6959 .  x - the result vectors
6960 
6961    Notes:
6962    The vectors b and x cannot be the same.  I.e., one cannot
6963    call MatSolves(A,x,x).
6964 
6965    Notes:
6966    Most users should employ the simplified KSP interface for linear solvers
6967    instead of working directly with matrix algebra routines such as this.
6968    See, e.g., KSPCreate().
6969 
6970    Level: developer
6971 
6972    Concepts: matrices^triangular solves
6973 
6974 .seealso: MatSolveAdd(), MatSolveTranspose(), MatSolveTransposeAdd(), MatSolve()
6975 @*/
6976 PetscErrorCode PETSCMAT_DLLEXPORT MatSolves(Mat mat,Vecs b,Vecs x)
6977 {
6978   PetscErrorCode ierr;
6979 
6980   PetscFunctionBegin;
6981   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6982   PetscValidType(mat,1);
6983   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
6984   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
6985   if (!mat->rmap->N && !mat->cmap->N) PetscFunctionReturn(0);
6986 
6987   if (!mat->ops->solves) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
6988   ierr = MatPreallocated(mat);CHKERRQ(ierr);
6989   ierr = PetscLogEventBegin(MAT_Solves,mat,0,0,0);CHKERRQ(ierr);
6990   ierr = (*mat->ops->solves)(mat,b,x);CHKERRQ(ierr);
6991   ierr = PetscLogEventEnd(MAT_Solves,mat,0,0,0);CHKERRQ(ierr);
6992   PetscFunctionReturn(0);
6993 }
6994 
6995 #undef __FUNCT__
6996 #define __FUNCT__ "MatIsSymmetric"
6997 /*@
6998    MatIsSymmetric - Test whether a matrix is symmetric
6999 
7000    Collective on Mat
7001 
7002    Input Parameter:
7003 +  A - the matrix to test
7004 -  tol - difference between value and its transpose less than this amount counts as equal (use 0.0 for exact transpose)
7005 
7006    Output Parameters:
7007 .  flg - the result
7008 
7009    Level: intermediate
7010 
7011    Concepts: matrix^symmetry
7012 
7013 .seealso: MatTranspose(), MatIsTranspose(), MatIsHermitian(), MatIsStructurallySymmetric(), MatSetOption(), MatIsSymmetricKnown()
7014 @*/
7015 PetscErrorCode PETSCMAT_DLLEXPORT MatIsSymmetric(Mat A,PetscReal tol,PetscTruth *flg)
7016 {
7017   PetscErrorCode ierr;
7018 
7019   PetscFunctionBegin;
7020   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
7021   PetscValidPointer(flg,2);
7022   if (!A->symmetric_set) {
7023     if (!A->ops->issymmetric) {
7024       const MatType mattype;
7025       ierr = MatGetType(A,&mattype);CHKERRQ(ierr);
7026       SETERRQ1(PETSC_ERR_SUP,"Matrix of type <%s> does not support checking for symmetric",mattype);
7027     }
7028     ierr = (*A->ops->issymmetric)(A,tol,&A->symmetric);CHKERRQ(ierr);
7029     A->symmetric_set = PETSC_TRUE;
7030     if (A->symmetric) {
7031       A->structurally_symmetric_set = PETSC_TRUE;
7032       A->structurally_symmetric     = PETSC_TRUE;
7033     }
7034   }
7035   *flg = A->symmetric;
7036   PetscFunctionReturn(0);
7037 }
7038 
7039 #undef __FUNCT__
7040 #define __FUNCT__ "MatIsHermitian"
7041 /*@
7042    MatIsHermitian - Test whether a matrix is Hermitian
7043 
7044    Collective on Mat
7045 
7046    Input Parameter:
7047 +  A - the matrix to test
7048 -  tol - difference between value and its transpose less than this amount counts as equal (use 0.0 for exact Hermitian)
7049 
7050    Output Parameters:
7051 .  flg - the result
7052 
7053    Level: intermediate
7054 
7055    Concepts: matrix^symmetry
7056 
7057 .seealso: MatTranspose(), MatIsTranspose(), MatIsHermitian(), MatIsStructurallySymmetric(), MatSetOption(), MatIsSymmetricKnown()
7058 @*/
7059 PetscErrorCode PETSCMAT_DLLEXPORT MatIsHermitian(Mat A,PetscReal tol,PetscTruth *flg)
7060 {
7061   PetscErrorCode ierr;
7062 
7063   PetscFunctionBegin;
7064   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
7065   PetscValidPointer(flg,2);
7066   if (!A->hermitian_set) {
7067     if (!A->ops->ishermitian) {
7068       const MatType mattype;
7069       ierr = MatGetType(A,&mattype);CHKERRQ(ierr);
7070       SETERRQ1(PETSC_ERR_SUP,"Matrix of type <%s> does not support checking for Hermitian",mattype);
7071     }
7072     ierr = (*A->ops->ishermitian)(A,tol,&A->hermitian);CHKERRQ(ierr);
7073     A->hermitian_set = PETSC_TRUE;
7074     if (A->hermitian) {
7075       A->structurally_symmetric_set = PETSC_TRUE;
7076       A->structurally_symmetric     = PETSC_TRUE;
7077     }
7078   }
7079   *flg = A->hermitian;
7080   PetscFunctionReturn(0);
7081 }
7082 
7083 #undef __FUNCT__
7084 #define __FUNCT__ "MatIsSymmetricKnown"
7085 /*@
7086    MatIsSymmetricKnown - Checks the flag on the matrix to see if it is symmetric.
7087 
7088    Collective on Mat
7089 
7090    Input Parameter:
7091 .  A - the matrix to check
7092 
7093    Output Parameters:
7094 +  set - if the symmetric flag is set (this tells you if the next flag is valid)
7095 -  flg - the result
7096 
7097    Level: advanced
7098 
7099    Concepts: matrix^symmetry
7100 
7101    Note: Does not check the matrix values directly, so this may return unknown (set = PETSC_FALSE). Use MatIsSymmetric()
7102          if you want it explicitly checked
7103 
7104 .seealso: MatTranspose(), MatIsTranspose(), MatIsHermitian(), MatIsStructurallySymmetric(), MatSetOption(), MatIsSymmetric()
7105 @*/
7106 PetscErrorCode PETSCMAT_DLLEXPORT MatIsSymmetricKnown(Mat A,PetscTruth *set,PetscTruth *flg)
7107 {
7108   PetscFunctionBegin;
7109   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
7110   PetscValidPointer(set,2);
7111   PetscValidPointer(flg,3);
7112   if (A->symmetric_set) {
7113     *set = PETSC_TRUE;
7114     *flg = A->symmetric;
7115   } else {
7116     *set = PETSC_FALSE;
7117   }
7118   PetscFunctionReturn(0);
7119 }
7120 
7121 #undef __FUNCT__
7122 #define __FUNCT__ "MatIsHermitianKnown"
7123 /*@
7124    MatIsHermitianKnown - Checks the flag on the matrix to see if it is hermitian.
7125 
7126    Collective on Mat
7127 
7128    Input Parameter:
7129 .  A - the matrix to check
7130 
7131    Output Parameters:
7132 +  set - if the hermitian flag is set (this tells you if the next flag is valid)
7133 -  flg - the result
7134 
7135    Level: advanced
7136 
7137    Concepts: matrix^symmetry
7138 
7139    Note: Does not check the matrix values directly, so this may return unknown (set = PETSC_FALSE). Use MatIsHermitian()
7140          if you want it explicitly checked
7141 
7142 .seealso: MatTranspose(), MatIsTranspose(), MatIsHermitian(), MatIsStructurallySymmetric(), MatSetOption(), MatIsSymmetric()
7143 @*/
7144 PetscErrorCode PETSCMAT_DLLEXPORT MatIsHermitianKnown(Mat A,PetscTruth *set,PetscTruth *flg)
7145 {
7146   PetscFunctionBegin;
7147   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
7148   PetscValidPointer(set,2);
7149   PetscValidPointer(flg,3);
7150   if (A->hermitian_set) {
7151     *set = PETSC_TRUE;
7152     *flg = A->hermitian;
7153   } else {
7154     *set = PETSC_FALSE;
7155   }
7156   PetscFunctionReturn(0);
7157 }
7158 
7159 #undef __FUNCT__
7160 #define __FUNCT__ "MatIsStructurallySymmetric"
7161 /*@
7162    MatIsStructurallySymmetric - Test whether a matrix is structurally symmetric
7163 
7164    Collective on Mat
7165 
7166    Input Parameter:
7167 .  A - the matrix to test
7168 
7169    Output Parameters:
7170 .  flg - the result
7171 
7172    Level: intermediate
7173 
7174    Concepts: matrix^symmetry
7175 
7176 .seealso: MatTranspose(), MatIsTranspose(), MatIsHermitian(), MatIsSymmetric(), MatSetOption()
7177 @*/
7178 PetscErrorCode PETSCMAT_DLLEXPORT MatIsStructurallySymmetric(Mat A,PetscTruth *flg)
7179 {
7180   PetscErrorCode ierr;
7181 
7182   PetscFunctionBegin;
7183   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
7184   PetscValidPointer(flg,2);
7185   if (!A->structurally_symmetric_set) {
7186     if (!A->ops->isstructurallysymmetric) SETERRQ(PETSC_ERR_SUP,"Matrix does not support checking for structural symmetric");
7187     ierr = (*A->ops->isstructurallysymmetric)(A,&A->structurally_symmetric);CHKERRQ(ierr);
7188     A->structurally_symmetric_set = PETSC_TRUE;
7189   }
7190   *flg = A->structurally_symmetric;
7191   PetscFunctionReturn(0);
7192 }
7193 
7194 #undef __FUNCT__
7195 #define __FUNCT__ "MatStashGetInfo"
7196 extern PetscErrorCode MatStashGetInfo_Private(MatStash*,PetscInt*,PetscInt*);
7197 /*@
7198    MatStashGetInfo - Gets how many values are currently in the vector stash, i.e. need
7199        to be communicated to other processors during the MatAssemblyBegin/End() process
7200 
7201     Not collective
7202 
7203    Input Parameter:
7204 .   vec - the vector
7205 
7206    Output Parameters:
7207 +   nstash   - the size of the stash
7208 .   reallocs - the number of additional mallocs incurred.
7209 .   bnstash   - the size of the block stash
7210 -   breallocs - the number of additional mallocs incurred.in the block stash
7211 
7212    Level: advanced
7213 
7214 .seealso: MatAssemblyBegin(), MatAssemblyEnd(), Mat, MatStashSetInitialSize()
7215 
7216 @*/
7217 PetscErrorCode PETSCMAT_DLLEXPORT MatStashGetInfo(Mat mat,PetscInt *nstash,PetscInt *reallocs,PetscInt *bnstash,PetscInt *breallocs)
7218 {
7219   PetscErrorCode ierr;
7220   PetscFunctionBegin;
7221   ierr = MatStashGetInfo_Private(&mat->stash,nstash,reallocs);CHKERRQ(ierr);
7222   ierr = MatStashGetInfo_Private(&mat->bstash,bnstash,breallocs);CHKERRQ(ierr);
7223   PetscFunctionReturn(0);
7224 }
7225 
7226 #undef __FUNCT__
7227 #define __FUNCT__ "MatGetVecs"
7228 /*@C
7229    MatGetVecs - Get vector(s) compatible with the matrix, i.e. with the same
7230      parallel layout
7231 
7232    Collective on Mat
7233 
7234    Input Parameter:
7235 .  mat - the matrix
7236 
7237    Output Parameter:
7238 +   right - (optional) vector that the matrix can be multiplied against
7239 -   left - (optional) vector that the matrix vector product can be stored in
7240 
7241   Level: advanced
7242 
7243 .seealso: MatCreate()
7244 @*/
7245 PetscErrorCode PETSCMAT_DLLEXPORT MatGetVecs(Mat mat,Vec *right,Vec *left)
7246 {
7247   PetscErrorCode ierr;
7248 
7249   PetscFunctionBegin;
7250   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
7251   PetscValidType(mat,1);
7252   ierr = MatPreallocated(mat);CHKERRQ(ierr);
7253   if (mat->ops->getvecs) {
7254     ierr = (*mat->ops->getvecs)(mat,right,left);CHKERRQ(ierr);
7255   } else {
7256     PetscMPIInt size;
7257     ierr = MPI_Comm_size(((PetscObject)mat)->comm, &size);CHKERRQ(ierr);
7258     if (right) {
7259       ierr = VecCreate(((PetscObject)mat)->comm,right);CHKERRQ(ierr);
7260       ierr = VecSetSizes(*right,mat->cmap->n,PETSC_DETERMINE);CHKERRQ(ierr);
7261       ierr = VecSetBlockSize(*right,mat->rmap->bs);CHKERRQ(ierr);
7262       if (size > 1) {
7263         /* New vectors uses Mat cmap and does not create a new one */
7264 	ierr = PetscMapDestroy((*right)->map);CHKERRQ(ierr);
7265 	(*right)->map = mat->cmap;
7266 	mat->cmap->refcnt++;
7267 
7268         ierr = VecSetType(*right,VECMPI);CHKERRQ(ierr);
7269       } else {ierr = VecSetType(*right,VECSEQ);CHKERRQ(ierr);}
7270     }
7271     if (left) {
7272       ierr = VecCreate(((PetscObject)mat)->comm,left);CHKERRQ(ierr);
7273       ierr = VecSetSizes(*left,mat->rmap->n,PETSC_DETERMINE);CHKERRQ(ierr);
7274       ierr = VecSetBlockSize(*left,mat->rmap->bs);CHKERRQ(ierr);
7275       if (size > 1) {
7276         /* New vectors uses Mat rmap and does not create a new one */
7277 	ierr = PetscMapDestroy((*left)->map);CHKERRQ(ierr);
7278 	(*left)->map = mat->rmap;
7279 	mat->rmap->refcnt++;
7280 
7281         ierr = VecSetType(*left,VECMPI);CHKERRQ(ierr);
7282       } else {ierr = VecSetType(*left,VECSEQ);CHKERRQ(ierr);}
7283     }
7284   }
7285   if (mat->mapping) {
7286     if (right) {ierr = VecSetLocalToGlobalMapping(*right,mat->mapping);CHKERRQ(ierr);}
7287     if (left) {ierr = VecSetLocalToGlobalMapping(*left,mat->mapping);CHKERRQ(ierr);}
7288   }
7289   if (mat->bmapping) {
7290     if (right) {ierr = VecSetLocalToGlobalMappingBlock(*right,mat->bmapping);CHKERRQ(ierr);}
7291     if (left) {ierr = VecSetLocalToGlobalMappingBlock(*left,mat->bmapping);CHKERRQ(ierr);}
7292   }
7293   PetscFunctionReturn(0);
7294 }
7295 
7296 #undef __FUNCT__
7297 #define __FUNCT__ "MatFactorInfoInitialize"
7298 /*@C
7299    MatFactorInfoInitialize - Initializes a MatFactorInfo data structure
7300      with default values.
7301 
7302    Not Collective
7303 
7304    Input Parameters:
7305 .    info - the MatFactorInfo data structure
7306 
7307 
7308    Notes: The solvers are generally used through the KSP and PC objects, for example
7309           PCLU, PCILU, PCCHOLESKY, PCICC
7310 
7311    Level: developer
7312 
7313 .seealso: MatFactorInfo
7314 
7315     Developer Note: fortran interface is not autogenerated as the f90
7316     interface defintion cannot be generated correctly [due to MatFactorInfo]
7317 
7318 @*/
7319 
7320 PetscErrorCode PETSCMAT_DLLEXPORT MatFactorInfoInitialize(MatFactorInfo *info)
7321 {
7322   PetscErrorCode ierr;
7323 
7324   PetscFunctionBegin;
7325   ierr = PetscMemzero(info,sizeof(MatFactorInfo));CHKERRQ(ierr);
7326   PetscFunctionReturn(0);
7327 }
7328 
7329 #undef __FUNCT__
7330 #define __FUNCT__ "MatPtAP"
7331 /*@
7332    MatPtAP - Creates the matrix projection C = P^T * A * P
7333 
7334    Collective on Mat
7335 
7336    Input Parameters:
7337 +  A - the matrix
7338 .  P - the projection matrix
7339 .  scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
7340 -  fill - expected fill as ratio of nnz(C)/nnz(A)
7341 
7342    Output Parameters:
7343 .  C - the product matrix
7344 
7345    Notes:
7346    C will be created and must be destroyed by the user with MatDestroy().
7347 
7348    This routine is currently only implemented for pairs of AIJ matrices and classes
7349    which inherit from AIJ.
7350 
7351    Level: intermediate
7352 
7353 .seealso: MatPtAPSymbolic(), MatPtAPNumeric(), MatMatMult()
7354 @*/
7355 PetscErrorCode PETSCMAT_DLLEXPORT MatPtAP(Mat A,Mat P,MatReuse scall,PetscReal fill,Mat *C)
7356 {
7357   PetscErrorCode ierr;
7358 
7359   PetscFunctionBegin;
7360   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
7361   PetscValidType(A,1);
7362   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7363   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7364   PetscValidHeaderSpecific(P,MAT_COOKIE,2);
7365   PetscValidType(P,2);
7366   ierr = MatPreallocated(P);CHKERRQ(ierr);
7367   if (!P->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7368   if (P->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7369   PetscValidPointer(C,3);
7370   if (P->rmap->N!=A->cmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",P->rmap->N,A->cmap->N);
7371   if (fill < 1.0) SETERRQ1(PETSC_ERR_ARG_SIZ,"Expected fill=%G must be >= 1.0",fill);
7372   ierr = MatPreallocated(A);CHKERRQ(ierr);
7373 
7374   ierr = PetscLogEventBegin(MAT_PtAP,A,P,0,0);CHKERRQ(ierr);
7375   ierr = (*A->ops->ptap)(A,P,scall,fill,C);CHKERRQ(ierr);
7376   ierr = PetscLogEventEnd(MAT_PtAP,A,P,0,0);CHKERRQ(ierr);
7377 
7378   PetscFunctionReturn(0);
7379 }
7380 
7381 #undef __FUNCT__
7382 #define __FUNCT__ "MatPtAPNumeric"
7383 /*@
7384    MatPtAPNumeric - Computes the matrix projection C = P^T * A * P
7385 
7386    Collective on Mat
7387 
7388    Input Parameters:
7389 +  A - the matrix
7390 -  P - the projection matrix
7391 
7392    Output Parameters:
7393 .  C - the product matrix
7394 
7395    Notes:
7396    C must have been created by calling MatPtAPSymbolic and must be destroyed by
7397    the user using MatDeatroy().
7398 
7399    This routine is currently only implemented for pairs of AIJ matrices and classes
7400    which inherit from AIJ.  C will be of type MATAIJ.
7401 
7402    Level: intermediate
7403 
7404 .seealso: MatPtAP(), MatPtAPSymbolic(), MatMatMultNumeric()
7405 @*/
7406 PetscErrorCode PETSCMAT_DLLEXPORT MatPtAPNumeric(Mat A,Mat P,Mat C)
7407 {
7408   PetscErrorCode ierr;
7409 
7410   PetscFunctionBegin;
7411   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
7412   PetscValidType(A,1);
7413   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7414   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7415   PetscValidHeaderSpecific(P,MAT_COOKIE,2);
7416   PetscValidType(P,2);
7417   ierr = MatPreallocated(P);CHKERRQ(ierr);
7418   if (!P->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7419   if (P->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7420   PetscValidHeaderSpecific(C,MAT_COOKIE,3);
7421   PetscValidType(C,3);
7422   ierr = MatPreallocated(C);CHKERRQ(ierr);
7423   if (C->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7424   if (P->cmap->N!=C->rmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",P->cmap->N,C->rmap->N);
7425   if (P->rmap->N!=A->cmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",P->rmap->N,A->cmap->N);
7426   if (A->rmap->N!=A->cmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix 'A' must be square, %D != %D",A->rmap->N,A->cmap->N);
7427   if (P->cmap->N!=C->cmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",P->cmap->N,C->cmap->N);
7428   ierr = MatPreallocated(A);CHKERRQ(ierr);
7429 
7430   ierr = PetscLogEventBegin(MAT_PtAPNumeric,A,P,0,0);CHKERRQ(ierr);
7431   ierr = (*A->ops->ptapnumeric)(A,P,C);CHKERRQ(ierr);
7432   ierr = PetscLogEventEnd(MAT_PtAPNumeric,A,P,0,0);CHKERRQ(ierr);
7433   PetscFunctionReturn(0);
7434 }
7435 
7436 #undef __FUNCT__
7437 #define __FUNCT__ "MatPtAPSymbolic"
7438 /*@
7439    MatPtAPSymbolic - Creates the (i,j) structure of the matrix projection C = P^T * A * P
7440 
7441    Collective on Mat
7442 
7443    Input Parameters:
7444 +  A - the matrix
7445 -  P - the projection matrix
7446 
7447    Output Parameters:
7448 .  C - the (i,j) structure of the product matrix
7449 
7450    Notes:
7451    C will be created and must be destroyed by the user with MatDestroy().
7452 
7453    This routine is currently only implemented for pairs of SeqAIJ matrices and classes
7454    which inherit from SeqAIJ.  C will be of type MATSEQAIJ.  The product is computed using
7455    this (i,j) structure by calling MatPtAPNumeric().
7456 
7457    Level: intermediate
7458 
7459 .seealso: MatPtAP(), MatPtAPNumeric(), MatMatMultSymbolic()
7460 @*/
7461 PetscErrorCode PETSCMAT_DLLEXPORT MatPtAPSymbolic(Mat A,Mat P,PetscReal fill,Mat *C)
7462 {
7463   PetscErrorCode ierr;
7464 
7465   PetscFunctionBegin;
7466   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
7467   PetscValidType(A,1);
7468   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7469   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7470   if (fill <1.0) SETERRQ1(PETSC_ERR_ARG_SIZ,"Expected fill=%G must be >= 1.0",fill);
7471   PetscValidHeaderSpecific(P,MAT_COOKIE,2);
7472   PetscValidType(P,2);
7473   ierr = MatPreallocated(P);CHKERRQ(ierr);
7474   if (!P->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7475   if (P->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7476   PetscValidPointer(C,3);
7477 
7478   if (P->rmap->N!=A->cmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",P->rmap->N,A->cmap->N);
7479   if (A->rmap->N!=A->cmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix 'A' must be square, %D != %D",A->rmap->N,A->cmap->N);
7480   ierr = MatPreallocated(A);CHKERRQ(ierr);
7481   ierr = PetscLogEventBegin(MAT_PtAPSymbolic,A,P,0,0);CHKERRQ(ierr);
7482   ierr = (*A->ops->ptapsymbolic)(A,P,fill,C);CHKERRQ(ierr);
7483   ierr = PetscLogEventEnd(MAT_PtAPSymbolic,A,P,0,0);CHKERRQ(ierr);
7484 
7485   ierr = MatSetBlockSize(*C,A->rmap->bs);CHKERRQ(ierr);
7486 
7487   PetscFunctionReturn(0);
7488 }
7489 
7490 #undef __FUNCT__
7491 #define __FUNCT__ "MatMatMult"
7492 /*@
7493    MatMatMult - Performs Matrix-Matrix Multiplication C=A*B.
7494 
7495    Collective on Mat
7496 
7497    Input Parameters:
7498 +  A - the left matrix
7499 .  B - the right matrix
7500 .  scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
7501 -  fill - expected fill as ratio of nnz(C)/(nnz(A) + nnz(B)), use PETSC_DEFAULT if you do not have a good estimate
7502           if the result is a dense matrix this is irrelevent
7503 
7504    Output Parameters:
7505 .  C - the product matrix
7506 
7507    Notes:
7508    Unless scall is MAT_REUSE_MATRIX C will be created.
7509 
7510    MAT_REUSE_MATRIX can only be used if the matrices A and B have the same nonzero pattern as in the previous call
7511 
7512    To determine the correct fill value, run with -info and search for the string "Fill ratio" to see the value
7513    actually needed.
7514 
7515    If you have many matrices with the same non-zero structure to multiply, you
7516    should either
7517 $   1) use MAT_REUSE_MATRIX in all calls but the first or
7518 $   2) call MatMatMultSymbolic() once and then MatMatMultNumeric() for each product needed
7519 
7520    Level: intermediate
7521 
7522 .seealso: MatMatMultSymbolic(), MatMatMultNumeric(), MatPtAP()
7523 @*/
7524 PetscErrorCode PETSCMAT_DLLEXPORT MatMatMult(Mat A,Mat B,MatReuse scall,PetscReal fill,Mat *C)
7525 {
7526   PetscErrorCode ierr;
7527   PetscErrorCode (*fA)(Mat,Mat,MatReuse,PetscReal,Mat*);
7528   PetscErrorCode (*fB)(Mat,Mat,MatReuse,PetscReal,Mat*);
7529   PetscErrorCode (*mult)(Mat,Mat,MatReuse,PetscReal,Mat *)=PETSC_NULL;
7530 
7531   PetscFunctionBegin;
7532   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
7533   PetscValidType(A,1);
7534   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7535   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7536   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
7537   PetscValidType(B,2);
7538   ierr = MatPreallocated(B);CHKERRQ(ierr);
7539   if (!B->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7540   if (B->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7541   PetscValidPointer(C,3);
7542   if (B->rmap->N!=A->cmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",B->rmap->N,A->cmap->N);
7543   if (scall == MAT_REUSE_MATRIX){
7544     PetscValidPointer(*C,5);
7545     PetscValidHeaderSpecific(*C,MAT_COOKIE,5);
7546   }
7547   if (fill == PETSC_DEFAULT || fill == PETSC_DECIDE) fill = 2.0;
7548   if (fill < 1.0) SETERRQ1(PETSC_ERR_ARG_SIZ,"Expected fill=%G must be >= 1.0",fill);
7549   ierr = MatPreallocated(A);CHKERRQ(ierr);
7550 
7551   fA = A->ops->matmult;
7552   fB = B->ops->matmult;
7553   if (fB == fA) {
7554     if (!fB) SETERRQ1(PETSC_ERR_SUP,"MatMatMult not supported for B of type %s",((PetscObject)B)->type_name);
7555     mult = fB;
7556   } else {
7557     /* dispatch based on the type of A and B */
7558     char  multname[256];
7559     ierr = PetscStrcpy(multname,"MatMatMult_");CHKERRQ(ierr);
7560     ierr = PetscStrcat(multname,((PetscObject)A)->type_name);CHKERRQ(ierr);
7561     ierr = PetscStrcat(multname,"_");CHKERRQ(ierr);
7562     ierr = PetscStrcat(multname,((PetscObject)B)->type_name);CHKERRQ(ierr);
7563     ierr = PetscStrcat(multname,"_C");CHKERRQ(ierr); /* e.g., multname = "MatMatMult_seqdense_seqaij_C" */
7564     ierr = PetscObjectQueryFunction((PetscObject)B,multname,(void (**)(void))&mult);CHKERRQ(ierr);
7565     if (!mult) SETERRQ2(PETSC_ERR_ARG_INCOMP,"MatMatMult requires A, %s, to be compatible with B, %s",((PetscObject)A)->type_name,((PetscObject)B)->type_name);
7566   }
7567   ierr = PetscLogEventBegin(MAT_MatMult,A,B,0,0);CHKERRQ(ierr);
7568   ierr = (*mult)(A,B,scall,fill,C);CHKERRQ(ierr);
7569   ierr = PetscLogEventEnd(MAT_MatMult,A,B,0,0);CHKERRQ(ierr);
7570   PetscFunctionReturn(0);
7571 }
7572 
7573 #undef __FUNCT__
7574 #define __FUNCT__ "MatMatMultSymbolic"
7575 /*@
7576    MatMatMultSymbolic - Performs construction, preallocation, and computes the ij structure
7577    of the matrix-matrix product C=A*B.  Call this routine before calling MatMatMultNumeric().
7578 
7579    Collective on Mat
7580 
7581    Input Parameters:
7582 +  A - the left matrix
7583 .  B - the right matrix
7584 -  fill - expected fill as ratio of nnz(C)/(nnz(A) + nnz(B)), use PETSC_DEFAULT if you do not have a good estimate,
7585       if C is a dense matrix this is irrelevent
7586 
7587    Output Parameters:
7588 .  C - the product matrix
7589 
7590    Notes:
7591    Unless scall is MAT_REUSE_MATRIX C will be created.
7592 
7593    To determine the correct fill value, run with -info and search for the string "Fill ratio" to see the value
7594    actually needed.
7595 
7596    This routine is currently implemented for
7597     - pairs of AIJ matrices and classes which inherit from AIJ, C will be of type AIJ
7598     - pairs of AIJ (A) and Dense (B) matrix, C will be of type Dense.
7599     - pairs of Dense (A) and AIJ (B) matrix, C will be of type Dense.
7600 
7601    Level: intermediate
7602 
7603 .seealso: MatMatMult(), MatMatMultNumeric()
7604 @*/
7605 PetscErrorCode PETSCMAT_DLLEXPORT MatMatMultSymbolic(Mat A,Mat B,PetscReal fill,Mat *C)
7606 {
7607   PetscErrorCode ierr;
7608   PetscErrorCode (*Asymbolic)(Mat,Mat,PetscReal,Mat *);
7609   PetscErrorCode (*Bsymbolic)(Mat,Mat,PetscReal,Mat *);
7610   PetscErrorCode (*symbolic)(Mat,Mat,PetscReal,Mat *)=PETSC_NULL;
7611 
7612   PetscFunctionBegin;
7613   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
7614   PetscValidType(A,1);
7615   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7616   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7617 
7618   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
7619   PetscValidType(B,2);
7620   ierr = MatPreallocated(B);CHKERRQ(ierr);
7621   if (!B->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7622   if (B->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7623   PetscValidPointer(C,3);
7624 
7625   if (B->rmap->N!=A->cmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",B->rmap->N,A->cmap->N);
7626   if (fill == PETSC_DEFAULT) fill = 2.0;
7627   if (fill < 1.0) SETERRQ1(PETSC_ERR_ARG_SIZ,"Expected fill=%G must be > 1.0",fill);
7628   ierr = MatPreallocated(A);CHKERRQ(ierr);
7629 
7630   Asymbolic = A->ops->matmultsymbolic;
7631   Bsymbolic = B->ops->matmultsymbolic;
7632   if (Asymbolic == Bsymbolic){
7633     if (!Bsymbolic) SETERRQ1(PETSC_ERR_SUP,"C=A*B not implemented for B of type %s",((PetscObject)B)->type_name);
7634     symbolic = Bsymbolic;
7635   } else { /* dispatch based on the type of A and B */
7636     char  symbolicname[256];
7637     ierr = PetscStrcpy(symbolicname,"MatMatMultSymbolic_");CHKERRQ(ierr);
7638     ierr = PetscStrcat(symbolicname,((PetscObject)A)->type_name);CHKERRQ(ierr);
7639     ierr = PetscStrcat(symbolicname,"_");CHKERRQ(ierr);
7640     ierr = PetscStrcat(symbolicname,((PetscObject)B)->type_name);CHKERRQ(ierr);
7641     ierr = PetscStrcat(symbolicname,"_C");CHKERRQ(ierr);
7642     ierr = PetscObjectQueryFunction((PetscObject)B,symbolicname,(void (**)(void))&symbolic);CHKERRQ(ierr);
7643     if (!symbolic) SETERRQ2(PETSC_ERR_ARG_INCOMP,"MatMatMultSymbolic requires A, %s, to be compatible with B, %s",((PetscObject)A)->type_name,((PetscObject)B)->type_name);
7644   }
7645   ierr = PetscLogEventBegin(MAT_MatMultSymbolic,A,B,0,0);CHKERRQ(ierr);
7646   ierr = (*symbolic)(A,B,fill,C);CHKERRQ(ierr);
7647   ierr = PetscLogEventEnd(MAT_MatMultSymbolic,A,B,0,0);CHKERRQ(ierr);
7648   PetscFunctionReturn(0);
7649 }
7650 
7651 #undef __FUNCT__
7652 #define __FUNCT__ "MatMatMultNumeric"
7653 /*@
7654    MatMatMultNumeric - Performs the numeric matrix-matrix product.
7655    Call this routine after first calling MatMatMultSymbolic().
7656 
7657    Collective on Mat
7658 
7659    Input Parameters:
7660 +  A - the left matrix
7661 -  B - the right matrix
7662 
7663    Output Parameters:
7664 .  C - the product matrix, which was created by from MatMatMultSymbolic() or a call to MatMatMult().
7665 
7666    Notes:
7667    C must have been created with MatMatMultSymbolic().
7668 
7669    This routine is currently implemented for
7670     - pairs of AIJ matrices and classes which inherit from AIJ, C will be of type MATAIJ.
7671     - pairs of AIJ (A) and Dense (B) matrix, C will be of type Dense.
7672     - pairs of Dense (A) and AIJ (B) matrix, C will be of type Dense.
7673 
7674    Level: intermediate
7675 
7676 .seealso: MatMatMult(), MatMatMultSymbolic()
7677 @*/
7678 PetscErrorCode PETSCMAT_DLLEXPORT MatMatMultNumeric(Mat A,Mat B,Mat C)
7679 {
7680   PetscErrorCode ierr;
7681   PetscErrorCode (*Anumeric)(Mat,Mat,Mat);
7682   PetscErrorCode (*Bnumeric)(Mat,Mat,Mat);
7683   PetscErrorCode (*numeric)(Mat,Mat,Mat)=PETSC_NULL;
7684 
7685   PetscFunctionBegin;
7686   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
7687   PetscValidType(A,1);
7688   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7689   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7690 
7691   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
7692   PetscValidType(B,2);
7693   ierr = MatPreallocated(B);CHKERRQ(ierr);
7694   if (!B->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7695   if (B->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7696 
7697   PetscValidHeaderSpecific(C,MAT_COOKIE,3);
7698   PetscValidType(C,3);
7699   ierr = MatPreallocated(C);CHKERRQ(ierr);
7700   if (!C->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7701   if (C->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7702 
7703   if (B->cmap->N!=C->cmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",B->cmap->N,C->cmap->N);
7704   if (B->rmap->N!=A->cmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",B->rmap->N,A->cmap->N);
7705   if (A->rmap->N!=C->rmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",A->rmap->N,C->rmap->N);
7706   ierr = MatPreallocated(A);CHKERRQ(ierr);
7707 
7708   Anumeric = A->ops->matmultnumeric;
7709   Bnumeric = B->ops->matmultnumeric;
7710   if (Anumeric == Bnumeric){
7711     if (!Bnumeric) SETERRQ1(PETSC_ERR_SUP,"MatMatMultNumeric not supported for B of type %s",((PetscObject)B)->type_name);
7712     numeric = Bnumeric;
7713   } else {
7714     char  numericname[256];
7715     ierr = PetscStrcpy(numericname,"MatMatMultNumeric_");CHKERRQ(ierr);
7716     ierr = PetscStrcat(numericname,((PetscObject)A)->type_name);CHKERRQ(ierr);
7717     ierr = PetscStrcat(numericname,"_");CHKERRQ(ierr);
7718     ierr = PetscStrcat(numericname,((PetscObject)B)->type_name);CHKERRQ(ierr);
7719     ierr = PetscStrcat(numericname,"_C");CHKERRQ(ierr);
7720     ierr = PetscObjectQueryFunction((PetscObject)B,numericname,(void (**)(void))&numeric);CHKERRQ(ierr);
7721     if (!numeric)
7722       SETERRQ2(PETSC_ERR_ARG_INCOMP,"MatMatMultNumeric requires A, %s, to be compatible with B, %s",((PetscObject)A)->type_name,((PetscObject)B)->type_name);
7723   }
7724   ierr = PetscLogEventBegin(MAT_MatMultNumeric,A,B,0,0);CHKERRQ(ierr);
7725   ierr = (*numeric)(A,B,C);CHKERRQ(ierr);
7726   ierr = PetscLogEventEnd(MAT_MatMultNumeric,A,B,0,0);CHKERRQ(ierr);
7727   PetscFunctionReturn(0);
7728 }
7729 
7730 #undef __FUNCT__
7731 #define __FUNCT__ "MatMatMultTranspose"
7732 /*@
7733    MatMatMultTranspose - Performs Matrix-Matrix Multiplication C=A^T*B.
7734 
7735    Collective on Mat
7736 
7737    Input Parameters:
7738 +  A - the left matrix
7739 .  B - the right matrix
7740 .  scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
7741 -  fill - expected fill as ratio of nnz(C)/(nnz(A) + nnz(B)), use PETSC_DEFAULT if not known
7742 
7743    Output Parameters:
7744 .  C - the product matrix
7745 
7746    Notes:
7747    C will be created if MAT_INITIAL_MATRIX and must be destroyed by the user with MatDestroy().
7748 
7749    MAT_REUSE_MATRIX can only be used if the matrices A and B have the same nonzero pattern as in the previous call
7750 
7751   To determine the correct fill value, run with -info and search for the string "Fill ratio" to see the value
7752    actually needed.
7753 
7754    This routine is currently only implemented for pairs of SeqAIJ matrices and pairs of SeqDense matrices and classes
7755    which inherit from SeqAIJ.  C will be of type MATSEQAIJ.
7756 
7757    Level: intermediate
7758 
7759 .seealso: MatMatMultTransposeSymbolic(), MatMatMultTransposeNumeric(), MatPtAP()
7760 @*/
7761 PetscErrorCode PETSCMAT_DLLEXPORT MatMatMultTranspose(Mat A,Mat B,MatReuse scall,PetscReal fill,Mat *C)
7762 {
7763   PetscErrorCode ierr;
7764   PetscErrorCode (*fA)(Mat,Mat,MatReuse,PetscReal,Mat*);
7765   PetscErrorCode (*fB)(Mat,Mat,MatReuse,PetscReal,Mat*);
7766 
7767   PetscFunctionBegin;
7768   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
7769   PetscValidType(A,1);
7770   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7771   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7772   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
7773   PetscValidType(B,2);
7774   ierr = MatPreallocated(B);CHKERRQ(ierr);
7775   if (!B->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7776   if (B->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7777   PetscValidPointer(C,3);
7778   if (B->rmap->N!=A->rmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",B->rmap->N,A->rmap->N);
7779   if (fill < 1.0) SETERRQ1(PETSC_ERR_ARG_SIZ,"Expected fill=%G must be > 1.0",fill);
7780   ierr = MatPreallocated(A);CHKERRQ(ierr);
7781 
7782   fA = A->ops->matmulttranspose;
7783   if (!fA) SETERRQ1(PETSC_ERR_SUP,"MatMatMultTranspose not supported for A of type %s",((PetscObject)A)->type_name);
7784   fB = B->ops->matmulttranspose;
7785   if (!fB) SETERRQ1(PETSC_ERR_SUP,"MatMatMultTranspose not supported for B of type %s",((PetscObject)B)->type_name);
7786   if (fB!=fA) SETERRQ2(PETSC_ERR_ARG_INCOMP,"MatMatMultTranspose requires A, %s, to be compatible with B, %s",((PetscObject)A)->type_name,((PetscObject)B)->type_name);
7787 
7788   ierr = PetscLogEventBegin(MAT_MatMultTranspose,A,B,0,0);CHKERRQ(ierr);
7789   ierr = (*A->ops->matmulttranspose)(A,B,scall,fill,C);CHKERRQ(ierr);
7790   ierr = PetscLogEventEnd(MAT_MatMultTranspose,A,B,0,0);CHKERRQ(ierr);
7791 
7792   PetscFunctionReturn(0);
7793 }
7794 
7795 #undef __FUNCT__
7796 #define __FUNCT__ "MatGetRedundantMatrix"
7797 /*@C
7798    MatGetRedundantMatrix - Create redundant matrices and put them into processors of subcommunicators.
7799 
7800    Collective on Mat
7801 
7802    Input Parameters:
7803 +  mat - the matrix
7804 .  nsubcomm - the number of subcommunicators (= number of redundant pareallel or sequential matrices)
7805 .  subcomm - MPI communicator split from the communicator where mat resides in
7806 .  mlocal_red - number of local rows of the redundant matrix
7807 -  reuse - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
7808 
7809    Output Parameter:
7810 .  matredundant - redundant matrix
7811 
7812    Notes:
7813    MAT_REUSE_MATRIX can only be used when the nonzero structure of the
7814    original matrix has not changed from that last call to MatGetRedundantMatrix().
7815 
7816    This routine creates the duplicated matrices in subcommunicators; you should NOT create them before
7817    calling it.
7818 
7819    Only MPIAIJ matrix is supported.
7820 
7821    Level: advanced
7822 
7823    Concepts: subcommunicator
7824    Concepts: duplicate matrix
7825 
7826 .seealso: MatDestroy()
7827 @*/
7828 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRedundantMatrix(Mat mat,PetscInt nsubcomm,MPI_Comm subcomm,PetscInt mlocal_red,MatReuse reuse,Mat *matredundant)
7829 {
7830   PetscErrorCode ierr;
7831 
7832   PetscFunctionBegin;
7833   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
7834   if (nsubcomm && reuse == MAT_REUSE_MATRIX) {
7835     PetscValidPointer(*matredundant,6);
7836     PetscValidHeaderSpecific(*matredundant,MAT_COOKIE,6);
7837   }
7838   if (!mat->ops->getredundantmatrix) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
7839   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7840   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7841   ierr = MatPreallocated(mat);CHKERRQ(ierr);
7842 
7843   ierr = PetscLogEventBegin(MAT_GetRedundantMatrix,mat,0,0,0);CHKERRQ(ierr);
7844   ierr = (*mat->ops->getredundantmatrix)(mat,nsubcomm,subcomm,mlocal_red,reuse,matredundant);CHKERRQ(ierr);
7845   ierr = PetscLogEventEnd(MAT_GetRedundantMatrix,mat,0,0,0);CHKERRQ(ierr);
7846   PetscFunctionReturn(0);
7847 }
7848