xref: /petsc/src/mat/interface/matrix.c (revision e87984cd163c0437b1c3d817d886654dc645598d)
1 #define PETSCMAT_DLL
2 
3 /*
4    This is where the abstract matrix operations are defined
5 */
6 
7 #include "include/private/matimpl.h"        /*I "petscmat.h" I*/
8 #include "private/vecimpl.h"
9 
10 /* Logging support */
11 PetscCookie PETSCMAT_DLLEXPORT MAT_COOKIE = 0;
12 PetscEvent  MAT_Mult = 0, MAT_Mults = 0, MAT_MultConstrained = 0, MAT_MultAdd = 0, MAT_MultTranspose = 0;
13 PetscEvent  MAT_MultTransposeConstrained = 0, MAT_MultTransposeAdd = 0, MAT_Solve = 0, MAT_Solves = 0, MAT_SolveAdd = 0, MAT_SolveTranspose = 0, MAT_MatSolve = 0;
14 PetscEvent  MAT_SolveTransposeAdd = 0, MAT_Relax = 0, MAT_ForwardSolve = 0, MAT_BackwardSolve = 0, MAT_LUFactor = 0, MAT_LUFactorSymbolic = 0;
15 PetscEvent  MAT_LUFactorNumeric = 0, MAT_CholeskyFactor = 0, MAT_CholeskyFactorSymbolic = 0, MAT_CholeskyFactorNumeric = 0, MAT_ILUFactor = 0;
16 PetscEvent  MAT_ILUFactorSymbolic = 0, MAT_ICCFactorSymbolic = 0, MAT_Copy = 0, MAT_Convert = 0, MAT_Scale = 0, MAT_AssemblyBegin = 0;
17 PetscEvent  MAT_AssemblyEnd = 0, MAT_SetValues = 0, MAT_GetValues = 0, MAT_GetRow = 0, MAT_GetRowIJ = 0, MAT_GetSubMatrices = 0, MAT_GetColoring = 0, MAT_GetOrdering = 0, MAT_GetRedundantMatrix = 0, MAT_GetSeqNonzeroStructure = 0;
18 PetscEvent  MAT_IncreaseOverlap = 0, MAT_Partitioning = 0, MAT_ZeroEntries = 0, MAT_Load = 0, MAT_View = 0, MAT_AXPY = 0, MAT_FDColoringCreate = 0;
19 PetscEvent  MAT_FDColoringApply = 0,MAT_Transpose = 0,MAT_FDColoringFunction = 0;
20 PetscEvent  MAT_MatMult = 0, MAT_MatMultSymbolic = 0, MAT_MatMultNumeric = 0;
21 PetscEvent  MAT_PtAP = 0, MAT_PtAPSymbolic = 0, MAT_PtAPNumeric = 0;
22 PetscEvent  MAT_MatMultTranspose = 0, MAT_MatMultTransposeSymbolic = 0, MAT_MatMultTransposeNumeric = 0;
23 PetscEvent  MAT_Getsymtranspose = 0, MAT_Getsymtransreduced = 0, MAT_Transpose_SeqAIJ = 0, MAT_GetBrowsOfAcols = 0;
24 PetscEvent  MAT_GetBrowsOfAocols = 0, MAT_Getlocalmat = 0, MAT_Getlocalmatcondensed = 0, MAT_Seqstompi = 0, MAT_Seqstompinum = 0, MAT_Seqstompisym = 0;
25 PetscEvent  MAT_Applypapt = 0, MAT_Applypapt_numeric = 0, MAT_Applypapt_symbolic = 0, MAT_GetSequentialNonzeroStructure = 0;
26 
27 /* nasty global values for MatSetValue() */
28 PetscInt    PETSCMAT_DLLEXPORT MatSetValue_Row = 0;
29 PetscInt    PETSCMAT_DLLEXPORT MatSetValue_Column = 0;
30 PetscScalar PETSCMAT_DLLEXPORT MatSetValue_Value = 0.0;
31 
32 #undef __FUNCT__
33 #define __FUNCT__ "MatRealPart"
34 /*@
35    MatRealPart - Zeros out the imaginary part of the matrix
36 
37    Collective on Mat
38 
39    Input Parameters:
40 .  mat - the matrix
41 
42    Level: advanced
43 
44 
45 .seealso: MatImaginaryPart()
46 @*/
47 
48 PetscErrorCode PETSCMAT_DLLEXPORT MatRealPart(Mat mat)
49 {
50   PetscErrorCode ierr;
51 
52   PetscFunctionBegin;
53   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
54   PetscValidType(mat,1);
55   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
56   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
57   if (!mat->ops->realpart) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
58   ierr = MatPreallocated(mat);CHKERRQ(ierr);
59   ierr = (*mat->ops->realpart)(mat);CHKERRQ(ierr);
60   PetscFunctionReturn(0);
61 }
62 
63 
64 #undef __FUNCT__
65 #define __FUNCT__ "MatImaginaryPart"
66 /*@
67    MatImaginaryPart - Moves the imaginary part of the matrix to the real part and zeros the imaginary part
68 
69    Collective on Mat
70 
71    Input Parameters:
72 .  mat - the matrix
73 
74    Level: advanced
75 
76 
77 .seealso: MatRealPart()
78 @*/
79 
80 PetscErrorCode PETSCMAT_DLLEXPORT MatImaginaryPart(Mat mat)
81 {
82   PetscErrorCode ierr;
83 
84   PetscFunctionBegin;
85   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
86   PetscValidType(mat,1);
87   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
88   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
89   if (!mat->ops->imaginarypart) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
90   ierr = MatPreallocated(mat);CHKERRQ(ierr);
91   ierr = (*mat->ops->imaginarypart)(mat);CHKERRQ(ierr);
92   PetscFunctionReturn(0);
93 }
94 
95 #undef __FUNCT__
96 #define __FUNCT__ "MatMissingDiagonal"
97 /*@
98    MatMissingDiagonal - Determine if sparse matrix is missing a diagonal entry (or block entry for BAIJ matrices)
99 
100    Collective on Mat
101 
102    Input Parameter:
103 .  mat - the matrix
104 
105    Output Parameters:
106 +  missing - is any diagonal missing
107 -  dd - first diagonal entry that is missing (optional)
108 
109    Level: advanced
110 
111 
112 .seealso: MatRealPart()
113 @*/
114 
115 PetscErrorCode PETSCMAT_DLLEXPORT MatMissingDiagonal(Mat mat,PetscTruth *missing,PetscInt *dd)
116 {
117   PetscErrorCode ierr;
118 
119   PetscFunctionBegin;
120   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
121   PetscValidType(mat,1);
122   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
123   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
124   if (!mat->ops->missingdiagonal) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
125   ierr = (*mat->ops->missingdiagonal)(mat,missing,dd);CHKERRQ(ierr);
126   PetscFunctionReturn(0);
127 }
128 
129 #undef __FUNCT__
130 #define __FUNCT__ "MatGetRow"
131 /*@C
132    MatGetRow - Gets a row of a matrix.  You MUST call MatRestoreRow()
133    for each row that you get to ensure that your application does
134    not bleed memory.
135 
136    Not Collective
137 
138    Input Parameters:
139 +  mat - the matrix
140 -  row - the row to get
141 
142    Output Parameters:
143 +  ncols -  if not NULL, the number of nonzeros in the row
144 .  cols - if not NULL, the column numbers
145 -  vals - if not NULL, the values
146 
147    Notes:
148    This routine is provided for people who need to have direct access
149    to the structure of a matrix.  We hope that we provide enough
150    high-level matrix routines that few users will need it.
151 
152    MatGetRow() always returns 0-based column indices, regardless of
153    whether the internal representation is 0-based (default) or 1-based.
154 
155    For better efficiency, set cols and/or vals to PETSC_NULL if you do
156    not wish to extract these quantities.
157 
158    The user can only examine the values extracted with MatGetRow();
159    the values cannot be altered.  To change the matrix entries, one
160    must use MatSetValues().
161 
162    You can only have one call to MatGetRow() outstanding for a particular
163    matrix at a time, per processor. MatGetRow() can only obtain rows
164    associated with the given processor, it cannot get rows from the
165    other processors; for that we suggest using MatGetSubMatrices(), then
166    MatGetRow() on the submatrix. The row indix passed to MatGetRows()
167    is in the global number of rows.
168 
169    Fortran Notes:
170    The calling sequence from Fortran is
171 .vb
172    MatGetRow(matrix,row,ncols,cols,values,ierr)
173          Mat     matrix (input)
174          integer row    (input)
175          integer ncols  (output)
176          integer cols(maxcols) (output)
177          double precision (or double complex) values(maxcols) output
178 .ve
179    where maxcols >= maximum nonzeros in any row of the matrix.
180 
181 
182    Caution:
183    Do not try to change the contents of the output arrays (cols and vals).
184    In some cases, this may corrupt the matrix.
185 
186    Level: advanced
187 
188    Concepts: matrices^row access
189 
190 .seealso: MatRestoreRow(), MatSetValues(), MatGetValues(), MatGetSubMatrices(), MatGetDiagonal()
191 @*/
192 
193 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRow(Mat mat,PetscInt row,PetscInt *ncols,const PetscInt *cols[],const PetscScalar *vals[])
194 {
195   PetscErrorCode ierr;
196   PetscInt       incols;
197 
198   PetscFunctionBegin;
199   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
200   PetscValidType(mat,1);
201   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
202   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
203   if (!mat->ops->getrow) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
204   ierr = MatPreallocated(mat);CHKERRQ(ierr);
205   ierr = PetscLogEventBegin(MAT_GetRow,mat,0,0,0);CHKERRQ(ierr);
206   ierr = (*mat->ops->getrow)(mat,row,&incols,(PetscInt **)cols,(PetscScalar **)vals);CHKERRQ(ierr);
207   if (ncols) *ncols = incols;
208   ierr = PetscLogEventEnd(MAT_GetRow,mat,0,0,0);CHKERRQ(ierr);
209   PetscFunctionReturn(0);
210 }
211 
212 #undef __FUNCT__
213 #define __FUNCT__ "MatConjugate"
214 /*@
215    MatConjugate - replaces the matrix values with their complex conjugates
216 
217    Collective on Mat
218 
219    Input Parameters:
220 .  mat - the matrix
221 
222    Level: advanced
223 
224 .seealso:  VecConjugate()
225 @*/
226 PetscErrorCode PETSCMAT_DLLEXPORT MatConjugate(Mat mat)
227 {
228   PetscErrorCode ierr;
229 
230   PetscFunctionBegin;
231   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
232   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
233   if (!mat->ops->conjugate) SETERRQ(PETSC_ERR_SUP,"Not provided for this matrix format, send email to petsc-maint@mcs.anl.gov");
234   ierr = (*mat->ops->conjugate)(mat);CHKERRQ(ierr);
235   PetscFunctionReturn(0);
236 }
237 
238 #undef __FUNCT__
239 #define __FUNCT__ "MatRestoreRow"
240 /*@C
241    MatRestoreRow - Frees any temporary space allocated by MatGetRow().
242 
243    Not Collective
244 
245    Input Parameters:
246 +  mat - the matrix
247 .  row - the row to get
248 .  ncols, cols - the number of nonzeros and their columns
249 -  vals - if nonzero the column values
250 
251    Notes:
252    This routine should be called after you have finished examining the entries.
253 
254    Fortran Notes:
255    The calling sequence from Fortran is
256 .vb
257    MatRestoreRow(matrix,row,ncols,cols,values,ierr)
258       Mat     matrix (input)
259       integer row    (input)
260       integer ncols  (output)
261       integer cols(maxcols) (output)
262       double precision (or double complex) values(maxcols) output
263 .ve
264    Where maxcols >= maximum nonzeros in any row of the matrix.
265 
266    In Fortran MatRestoreRow() MUST be called after MatGetRow()
267    before another call to MatGetRow() can be made.
268 
269    Level: advanced
270 
271 .seealso:  MatGetRow()
272 @*/
273 PetscErrorCode PETSCMAT_DLLEXPORT MatRestoreRow(Mat mat,PetscInt row,PetscInt *ncols,const PetscInt *cols[],const PetscScalar *vals[])
274 {
275   PetscErrorCode ierr;
276 
277   PetscFunctionBegin;
278   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
279   PetscValidIntPointer(ncols,3);
280   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
281   if (!mat->ops->restorerow) PetscFunctionReturn(0);
282   ierr = (*mat->ops->restorerow)(mat,row,ncols,(PetscInt **)cols,(PetscScalar **)vals);CHKERRQ(ierr);
283   PetscFunctionReturn(0);
284 }
285 
286 #undef __FUNCT__
287 #define __FUNCT__ "MatGetRowUpperTriangular"
288 /*@C
289    MatGetRowUpperTriangular - Sets a flag to enable calls to MatGetRow() for matrix in MATSBAIJ format.
290    You should call MatRestoreRowUpperTriangular() after calling MatGetRow/MatRestoreRow() to disable the flag.
291 
292    Not Collective
293 
294    Input Parameters:
295 +  mat - the matrix
296 
297    Notes:
298    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.
299 
300    Level: advanced
301 
302    Concepts: matrices^row access
303 
304 .seealso: MatRestoreRowRowUpperTriangular()
305 @*/
306 
307 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRowUpperTriangular(Mat mat)
308 {
309   PetscErrorCode ierr;
310 
311   PetscFunctionBegin;
312   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
313   PetscValidType(mat,1);
314   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
315   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
316   if (!mat->ops->getrowuppertriangular) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
317   ierr = MatPreallocated(mat);CHKERRQ(ierr);
318   ierr = (*mat->ops->getrowuppertriangular)(mat);CHKERRQ(ierr);
319   PetscFunctionReturn(0);
320 }
321 
322 #undef __FUNCT__
323 #define __FUNCT__ "MatRestoreRowUpperTriangular"
324 /*@C
325    MatRestoreRowUpperTriangular - Disable calls to MatGetRow() for matrix in MATSBAIJ format.
326 
327    Not Collective
328 
329    Input Parameters:
330 +  mat - the matrix
331 
332    Notes:
333    This routine should be called after you have finished MatGetRow/MatRestoreRow().
334 
335 
336    Level: advanced
337 
338 .seealso:  MatGetRowUpperTriangular()
339 @*/
340 PetscErrorCode PETSCMAT_DLLEXPORT MatRestoreRowUpperTriangular(Mat mat)
341 {
342   PetscErrorCode ierr;
343 
344   PetscFunctionBegin;
345   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
346   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
347   if (!mat->ops->restorerowuppertriangular) PetscFunctionReturn(0);
348   ierr = (*mat->ops->restorerowuppertriangular)(mat);CHKERRQ(ierr);
349   PetscFunctionReturn(0);
350 }
351 
352 #undef __FUNCT__
353 #define __FUNCT__ "MatSetOptionsPrefix"
354 /*@C
355    MatSetOptionsPrefix - Sets the prefix used for searching for all
356    Mat options in the database.
357 
358    Collective on Mat
359 
360    Input Parameter:
361 +  A - the Mat context
362 -  prefix - the prefix to prepend to all option names
363 
364    Notes:
365    A hyphen (-) must NOT be given at the beginning of the prefix name.
366    The first character of all runtime options is AUTOMATICALLY the hyphen.
367 
368    Level: advanced
369 
370 .keywords: Mat, set, options, prefix, database
371 
372 .seealso: MatSetFromOptions()
373 @*/
374 PetscErrorCode PETSCMAT_DLLEXPORT MatSetOptionsPrefix(Mat A,const char prefix[])
375 {
376   PetscErrorCode ierr;
377 
378   PetscFunctionBegin;
379   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
380   ierr = PetscObjectSetOptionsPrefix((PetscObject)A,prefix);CHKERRQ(ierr);
381   PetscFunctionReturn(0);
382 }
383 
384 #undef __FUNCT__
385 #define __FUNCT__ "MatAppendOptionsPrefix"
386 /*@C
387    MatAppendOptionsPrefix - Appends to the prefix used for searching for all
388    Mat options in the database.
389 
390    Collective on Mat
391 
392    Input Parameters:
393 +  A - the Mat context
394 -  prefix - the prefix to prepend to all option names
395 
396    Notes:
397    A hyphen (-) must NOT be given at the beginning of the prefix name.
398    The first character of all runtime options is AUTOMATICALLY the hyphen.
399 
400    Level: advanced
401 
402 .keywords: Mat, append, options, prefix, database
403 
404 .seealso: MatGetOptionsPrefix()
405 @*/
406 PetscErrorCode PETSCMAT_DLLEXPORT MatAppendOptionsPrefix(Mat A,const char prefix[])
407 {
408   PetscErrorCode ierr;
409 
410   PetscFunctionBegin;
411   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
412   ierr = PetscObjectAppendOptionsPrefix((PetscObject)A,prefix);CHKERRQ(ierr);
413   PetscFunctionReturn(0);
414 }
415 
416 #undef __FUNCT__
417 #define __FUNCT__ "MatGetOptionsPrefix"
418 /*@C
419    MatGetOptionsPrefix - Sets the prefix used for searching for all
420    Mat options in the database.
421 
422    Not Collective
423 
424    Input Parameter:
425 .  A - the Mat context
426 
427    Output Parameter:
428 .  prefix - pointer to the prefix string used
429 
430    Notes: On the fortran side, the user should pass in a string 'prefix' of
431    sufficient length to hold the prefix.
432 
433    Level: advanced
434 
435 .keywords: Mat, get, options, prefix, database
436 
437 .seealso: MatAppendOptionsPrefix()
438 @*/
439 PetscErrorCode PETSCMAT_DLLEXPORT MatGetOptionsPrefix(Mat A,const char *prefix[])
440 {
441   PetscErrorCode ierr;
442 
443   PetscFunctionBegin;
444   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
445   ierr = PetscObjectGetOptionsPrefix((PetscObject)A,prefix);CHKERRQ(ierr);
446   PetscFunctionReturn(0);
447 }
448 
449 #undef __FUNCT__
450 #define __FUNCT__ "MatSetUp"
451 /*@
452    MatSetUp - Sets up the internal matrix data structures for the later use.
453 
454    Collective on Mat
455 
456    Input Parameters:
457 .  A - the Mat context
458 
459    Notes:
460    For basic use of the Mat classes the user need not explicitly call
461    MatSetUp(), since these actions will happen automatically.
462 
463    Level: advanced
464 
465 .keywords: Mat, setup
466 
467 .seealso: MatCreate(), MatDestroy()
468 @*/
469 PetscErrorCode PETSCMAT_DLLEXPORT MatSetUp(Mat A)
470 {
471   PetscMPIInt    size;
472   PetscErrorCode ierr;
473 
474   PetscFunctionBegin;
475   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
476   if (!((PetscObject)A)->type_name) {
477     ierr = MPI_Comm_size(((PetscObject)A)->comm, &size);CHKERRQ(ierr);
478     if (size == 1) {
479       ierr = MatSetType(A, MATSEQAIJ);CHKERRQ(ierr);
480     } else {
481       ierr = MatSetType(A, MATMPIAIJ);CHKERRQ(ierr);
482     }
483   }
484   ierr = MatSetUpPreallocation(A);CHKERRQ(ierr);
485   PetscFunctionReturn(0);
486 }
487 
488 #undef __FUNCT__
489 #define __FUNCT__ "MatView"
490 /*@C
491    MatView - Visualizes a matrix object.
492 
493    Collective on Mat
494 
495    Input Parameters:
496 +  mat - the matrix
497 -  viewer - visualization context
498 
499   Notes:
500   The available visualization contexts include
501 +    PETSC_VIEWER_STDOUT_SELF - standard output (default)
502 .    PETSC_VIEWER_STDOUT_WORLD - synchronized standard
503         output where only the first processor opens
504         the file.  All other processors send their
505         data to the first processor to print.
506 -     PETSC_VIEWER_DRAW_WORLD - graphical display of nonzero structure
507 
508    The user can open alternative visualization contexts with
509 +    PetscViewerASCIIOpen() - Outputs matrix to a specified file
510 .    PetscViewerBinaryOpen() - Outputs matrix in binary to a
511          specified file; corresponding input uses MatLoad()
512 .    PetscViewerDrawOpen() - Outputs nonzero matrix structure to
513          an X window display
514 -    PetscViewerSocketOpen() - Outputs matrix to Socket viewer.
515          Currently only the sequential dense and AIJ
516          matrix types support the Socket viewer.
517 
518    The user can call PetscViewerSetFormat() to specify the output
519    format of ASCII printed objects (when using PETSC_VIEWER_STDOUT_SELF,
520    PETSC_VIEWER_STDOUT_WORLD and PetscViewerASCIIOpen).  Available formats include
521 +    PETSC_VIEWER_ASCII_DEFAULT - default, prints matrix contents
522 .    PETSC_VIEWER_ASCII_MATLAB - prints matrix contents in Matlab format
523 .    PETSC_VIEWER_ASCII_DENSE - prints entire matrix including zeros
524 .    PETSC_VIEWER_ASCII_COMMON - prints matrix contents, using a sparse
525          format common among all matrix types
526 .    PETSC_VIEWER_ASCII_IMPL - prints matrix contents, using an implementation-specific
527          format (which is in many cases the same as the default)
528 .    PETSC_VIEWER_ASCII_INFO - prints basic information about the matrix
529          size and structure (not the matrix entries)
530 .    PETSC_VIEWER_ASCII_INFO_DETAIL - prints more detailed information about
531          the matrix structure
532 
533    Options Database Keys:
534 +  -mat_view_info - Prints info on matrix at conclusion of MatEndAssembly()
535 .  -mat_view_info_detailed - Prints more detailed info
536 .  -mat_view - Prints matrix in ASCII format
537 .  -mat_view_matlab - Prints matrix in Matlab format
538 .  -mat_view_draw - PetscDraws nonzero structure of matrix, using MatView() and PetscDrawOpenX().
539 .  -display <name> - Sets display name (default is host)
540 .  -draw_pause <sec> - Sets number of seconds to pause after display
541 .  -mat_view_socket - Sends matrix to socket, can be accessed from Matlab (see users manual)
542 .  -viewer_socket_machine <machine>
543 .  -viewer_socket_port <port>
544 .  -mat_view_binary - save matrix to file in binary format
545 -  -viewer_binary_filename <name>
546    Level: beginner
547 
548    Concepts: matrices^viewing
549    Concepts: matrices^plotting
550    Concepts: matrices^printing
551 
552 .seealso: PetscViewerSetFormat(), PetscViewerASCIIOpen(), PetscViewerDrawOpen(),
553           PetscViewerSocketOpen(), PetscViewerBinaryOpen(), MatLoad()
554 @*/
555 PetscErrorCode PETSCMAT_DLLEXPORT MatView(Mat mat,PetscViewer viewer)
556 {
557   PetscErrorCode    ierr;
558   PetscInt          rows,cols;
559   PetscTruth        iascii;
560   const char        *cstr;
561   PetscViewerFormat format;
562 
563   PetscFunctionBegin;
564   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
565   PetscValidType(mat,1);
566   if (!viewer) {
567     ierr = PetscViewerASCIIGetStdout(((PetscObject)mat)->comm,&viewer);CHKERRQ(ierr);
568   }
569   PetscValidHeaderSpecific(viewer,PETSC_VIEWER_COOKIE,2);
570   PetscCheckSameComm(mat,1,viewer,2);
571   if (!mat->assembled) SETERRQ(PETSC_ERR_ORDER,"Must call MatAssemblyBegin/End() before viewing matrix");
572   ierr = MatPreallocated(mat);CHKERRQ(ierr);
573 
574   ierr = PetscTypeCompare((PetscObject)viewer,PETSC_VIEWER_ASCII,&iascii);CHKERRQ(ierr);
575   if (iascii) {
576     ierr = PetscViewerGetFormat(viewer,&format);CHKERRQ(ierr);
577     if (format == PETSC_VIEWER_ASCII_INFO || format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
578       if (((PetscObject)mat)->prefix) {
579         ierr = PetscViewerASCIIPrintf(viewer,"Matrix Object:(%s)\n",((PetscObject)mat)->prefix);CHKERRQ(ierr);
580       } else {
581         ierr = PetscViewerASCIIPrintf(viewer,"Matrix Object:\n");CHKERRQ(ierr);
582       }
583       ierr = PetscViewerASCIIPushTab(viewer);CHKERRQ(ierr);
584       ierr = MatGetType(mat,&cstr);CHKERRQ(ierr);
585       ierr = MatGetSize(mat,&rows,&cols);CHKERRQ(ierr);
586       ierr = PetscViewerASCIIPrintf(viewer,"type=%s, rows=%D, cols=%D\n",cstr,rows,cols);CHKERRQ(ierr);
587       if (mat->ops->getinfo) {
588         MatInfo info;
589         ierr = MatGetInfo(mat,MAT_GLOBAL_SUM,&info);CHKERRQ(ierr);
590         ierr = PetscViewerASCIIPrintf(viewer,"total: nonzeros=%D, allocated nonzeros=%D\n",
591                           (PetscInt)info.nz_used,(PetscInt)info.nz_allocated);CHKERRQ(ierr);
592       }
593     }
594   }
595   if (mat->ops->view) {
596     ierr = PetscViewerASCIIPushTab(viewer);CHKERRQ(ierr);
597     ierr = (*mat->ops->view)(mat,viewer);CHKERRQ(ierr);
598     ierr = PetscViewerASCIIPopTab(viewer);CHKERRQ(ierr);
599   } else if (!iascii) {
600     SETERRQ1(PETSC_ERR_SUP,"Viewer type %s not supported",((PetscObject)viewer)->type_name);
601   }
602   if (iascii) {
603     ierr = PetscViewerGetFormat(viewer,&format);CHKERRQ(ierr);
604     if (format == PETSC_VIEWER_ASCII_INFO || format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
605       ierr = PetscViewerASCIIPopTab(viewer);CHKERRQ(ierr);
606     }
607   }
608   PetscFunctionReturn(0);
609 }
610 
611 #undef __FUNCT__
612 #define __FUNCT__ "MatScaleSystem"
613 /*@
614    MatScaleSystem - Scale a vector solution and right hand side to
615    match the scaling of a scaled matrix.
616 
617    Collective on Mat
618 
619    Input Parameter:
620 +  mat - the matrix
621 .  b - right hand side vector (or PETSC_NULL)
622 -  x - solution vector (or PETSC_NULL)
623 
624 
625    Notes:
626    For AIJ, and BAIJ matrix formats, the matrices are not
627    internally scaled, so this does nothing. For MPIROWBS it
628    permutes and diagonally scales.
629 
630    The KSP methods automatically call this routine when required
631    (via PCPreSolve()) so it is rarely used directly.
632 
633    Level: Developer
634 
635    Concepts: matrices^scaling
636 
637 .seealso: MatUseScaledForm(), MatUnScaleSystem()
638 @*/
639 PetscErrorCode PETSCMAT_DLLEXPORT MatScaleSystem(Mat mat,Vec b,Vec x)
640 {
641   PetscErrorCode ierr;
642 
643   PetscFunctionBegin;
644   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
645   PetscValidType(mat,1);
646   ierr = MatPreallocated(mat);CHKERRQ(ierr);
647   if (x) {PetscValidHeaderSpecific(x,VEC_COOKIE,2);PetscCheckSameComm(mat,1,x,2);}
648   if (b) {PetscValidHeaderSpecific(b,VEC_COOKIE,3);PetscCheckSameComm(mat,1,b,3);}
649 
650   if (mat->ops->scalesystem) {
651     ierr = (*mat->ops->scalesystem)(mat,b,x);CHKERRQ(ierr);
652   }
653   PetscFunctionReturn(0);
654 }
655 
656 #undef __FUNCT__
657 #define __FUNCT__ "MatUnScaleSystem"
658 /*@
659    MatUnScaleSystem - Unscales a vector solution and right hand side to
660    match the original scaling of a scaled matrix.
661 
662    Collective on Mat
663 
664    Input Parameter:
665 +  mat - the matrix
666 .  b - right hand side vector (or PETSC_NULL)
667 -  x - solution vector (or PETSC_NULL)
668 
669 
670    Notes:
671    For AIJ and BAIJ matrix formats, the matrices are not
672    internally scaled, so this does nothing. For MPIROWBS it
673    permutes and diagonally scales.
674 
675    The KSP methods automatically call this routine when required
676    (via PCPreSolve()) so it is rarely used directly.
677 
678    Level: Developer
679 
680 .seealso: MatUseScaledForm(), MatScaleSystem()
681 @*/
682 PetscErrorCode PETSCMAT_DLLEXPORT MatUnScaleSystem(Mat mat,Vec b,Vec x)
683 {
684   PetscErrorCode ierr;
685 
686   PetscFunctionBegin;
687   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
688   PetscValidType(mat,1);
689   ierr = MatPreallocated(mat);CHKERRQ(ierr);
690   if (x) {PetscValidHeaderSpecific(x,VEC_COOKIE,2);PetscCheckSameComm(mat,1,x,2);}
691   if (b) {PetscValidHeaderSpecific(b,VEC_COOKIE,3);PetscCheckSameComm(mat,1,b,3);}
692   if (mat->ops->unscalesystem) {
693     ierr = (*mat->ops->unscalesystem)(mat,b,x);CHKERRQ(ierr);
694   }
695   PetscFunctionReturn(0);
696 }
697 
698 #undef __FUNCT__
699 #define __FUNCT__ "MatUseScaledForm"
700 /*@
701    MatUseScaledForm - For matrix storage formats that scale the
702    matrix (for example MPIRowBS matrices are diagonally scaled on
703    assembly) indicates matrix operations (MatMult() etc) are
704    applied using the scaled matrix.
705 
706    Collective on Mat
707 
708    Input Parameter:
709 +  mat - the matrix
710 -  scaled - PETSC_TRUE for applying the scaled, PETSC_FALSE for
711             applying the original matrix
712 
713    Notes:
714    For scaled matrix formats, applying the original, unscaled matrix
715    will be slightly more expensive
716 
717    Level: Developer
718 
719 .seealso: MatScaleSystem(), MatUnScaleSystem()
720 @*/
721 PetscErrorCode PETSCMAT_DLLEXPORT MatUseScaledForm(Mat mat,PetscTruth scaled)
722 {
723   PetscErrorCode ierr;
724 
725   PetscFunctionBegin;
726   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
727   PetscValidType(mat,1);
728   ierr = MatPreallocated(mat);CHKERRQ(ierr);
729   if (mat->ops->usescaledform) {
730     ierr = (*mat->ops->usescaledform)(mat,scaled);CHKERRQ(ierr);
731   }
732   PetscFunctionReturn(0);
733 }
734 
735 #undef __FUNCT__
736 #define __FUNCT__ "MatDestroy"
737 /*@
738    MatDestroy - Frees space taken by a matrix.
739 
740    Collective on Mat
741 
742    Input Parameter:
743 .  A - the matrix
744 
745    Level: beginner
746 
747 @*/
748 PetscErrorCode PETSCMAT_DLLEXPORT MatDestroy(Mat A)
749 {
750   PetscErrorCode ierr;
751   PetscFunctionBegin;
752   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
753   if (--((PetscObject)A)->refct > 0) PetscFunctionReturn(0);
754   ierr = MatPreallocated(A);CHKERRQ(ierr);
755   /* if memory was published with AMS then destroy it */
756   ierr = PetscObjectDepublish(A);CHKERRQ(ierr);
757   if (A->ops->destroy) {
758     ierr = (*A->ops->destroy)(A);CHKERRQ(ierr);
759   }
760   if (A->mapping) {
761     ierr = ISLocalToGlobalMappingDestroy(A->mapping);CHKERRQ(ierr);
762   }
763   if (A->bmapping) {
764     ierr = ISLocalToGlobalMappingDestroy(A->bmapping);CHKERRQ(ierr);
765   }
766   ierr = PetscFree(A->rmap.range);CHKERRQ(ierr);
767   ierr = PetscFree(A->cmap.range);CHKERRQ(ierr);
768   if (A->spptr){ierr = PetscFree(A->spptr);CHKERRQ(ierr);}
769   ierr = PetscHeaderDestroy(A);CHKERRQ(ierr);
770   PetscFunctionReturn(0);
771 }
772 
773 #undef __FUNCT__
774 #define __FUNCT__ "MatValid"
775 /*@
776    MatValid - Checks whether a matrix object is valid.
777 
778    Collective on Mat
779 
780    Input Parameter:
781 .  m - the matrix to check
782 
783    Output Parameter:
784    flg - flag indicating matrix status, either
785    PETSC_TRUE if matrix is valid, or PETSC_FALSE otherwise.
786 
787    Level: developer
788 
789    Concepts: matrices^validity
790 @*/
791 PetscErrorCode PETSCMAT_DLLEXPORT MatValid(Mat m,PetscTruth *flg)
792 {
793   PetscFunctionBegin;
794   PetscValidIntPointer(flg,1);
795   if (!m)                                          *flg = PETSC_FALSE;
796   else if (((PetscObject)m)->cookie != MAT_COOKIE) *flg = PETSC_FALSE;
797   else                                             *flg = PETSC_TRUE;
798   PetscFunctionReturn(0);
799 }
800 
801 #undef __FUNCT__
802 #define __FUNCT__ "MatSetValues"
803 /*@
804    MatSetValues - Inserts or adds a block of values into a matrix.
805    These values may be cached, so MatAssemblyBegin() and MatAssemblyEnd()
806    MUST be called after all calls to MatSetValues() have been completed.
807 
808    Not Collective
809 
810    Input Parameters:
811 +  mat - the matrix
812 .  v - a logically two-dimensional array of values
813 .  m, idxm - the number of rows and their global indices
814 .  n, idxn - the number of columns and their global indices
815 -  addv - either ADD_VALUES or INSERT_VALUES, where
816    ADD_VALUES adds values to any existing entries, and
817    INSERT_VALUES replaces existing entries with new values
818 
819    Notes:
820    By default the values, v, are row-oriented and unsorted.
821    See MatSetOption() for other options.
822 
823    Calls to MatSetValues() with the INSERT_VALUES and ADD_VALUES
824    options cannot be mixed without intervening calls to the assembly
825    routines.
826 
827    MatSetValues() uses 0-based row and column numbers in Fortran
828    as well as in C.
829 
830    Negative indices may be passed in idxm and idxn, these rows and columns are
831    simply ignored. This allows easily inserting element stiffness matrices
832    with homogeneous Dirchlet boundary conditions that you don't want represented
833    in the matrix.
834 
835    Efficiency Alert:
836    The routine MatSetValuesBlocked() may offer much better efficiency
837    for users of block sparse formats (MATSEQBAIJ and MATMPIBAIJ).
838 
839    Level: beginner
840 
841    Concepts: matrices^putting entries in
842 
843 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal(),
844           InsertMode, INSERT_VALUES, ADD_VALUES
845 @*/
846 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValues(Mat mat,PetscInt m,const PetscInt idxm[],PetscInt n,const PetscInt idxn[],const PetscScalar v[],InsertMode addv)
847 {
848   PetscErrorCode ierr;
849 
850   PetscFunctionBegin;
851   if (!m || !n) PetscFunctionReturn(0); /* no values to insert */
852   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
853   PetscValidType(mat,1);
854   PetscValidIntPointer(idxm,3);
855   PetscValidIntPointer(idxn,5);
856   PetscValidScalarPointer(v,6);
857   ierr = MatPreallocated(mat);CHKERRQ(ierr);
858   if (mat->insertmode == NOT_SET_VALUES) {
859     mat->insertmode = addv;
860   }
861 #if defined(PETSC_USE_DEBUG)
862   else if (mat->insertmode != addv) {
863     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
864   }
865   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
866 #endif
867 
868   if (mat->assembled) {
869     mat->was_assembled = PETSC_TRUE;
870     mat->assembled     = PETSC_FALSE;
871   }
872   ierr = PetscLogEventBegin(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
873   if (!mat->ops->setvalues) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
874   ierr = (*mat->ops->setvalues)(mat,m,idxm,n,idxn,v,addv);CHKERRQ(ierr);
875   ierr = PetscLogEventEnd(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
876   PetscFunctionReturn(0);
877 }
878 
879 
880 #undef __FUNCT__
881 #define __FUNCT__ "MatSetValuesRowLocal"
882 /*@
883    MatSetValuesRowLocal - Inserts a row (block row for BAIJ matrices) of nonzero
884         values into a matrix
885 
886    Not Collective
887 
888    Input Parameters:
889 +  mat - the matrix
890 .  row - the (block) row to set
891 -  v - a logically two-dimensional array of values
892 
893    Notes:
894    By the values, v, are column-oriented (for the block version) and sorted
895 
896    All the nonzeros in the row must be provided
897 
898    The matrix must have previously had its column indices set
899 
900    The row must belong to this process
901 
902    Level: intermediate
903 
904    Concepts: matrices^putting entries in
905 
906 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal(),
907           InsertMode, INSERT_VALUES, ADD_VALUES, MatSetValues(), MatSetValuesRow(), MatSetLocalToGlobalMapping()
908 @*/
909 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesRowLocal(Mat mat,PetscInt row,const PetscScalar v[])
910 {
911   PetscErrorCode ierr;
912 
913   PetscFunctionBegin;
914   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
915   PetscValidType(mat,1);
916   PetscValidScalarPointer(v,2);
917   ierr = MatSetValuesRow(mat, mat->mapping->indices[row],v);CHKERRQ(ierr);
918   PetscFunctionReturn(0);
919 }
920 
921 #undef __FUNCT__
922 #define __FUNCT__ "MatSetValuesRow"
923 /*@
924    MatSetValuesRow - Inserts a row (block row for BAIJ matrices) of nonzero
925         values into a matrix
926 
927    Not Collective
928 
929    Input Parameters:
930 +  mat - the matrix
931 .  row - the (block) row to set
932 -  v - a logically two-dimensional array of values
933 
934    Notes:
935    By the values, v, are column-oriented (for the block version) and sorted
936 
937    All the nonzeros in the row must be provided
938 
939    The matrix must have previously had its column indices set
940 
941    The row must belong to this process
942 
943    Level: intermediate
944 
945    Concepts: matrices^putting entries in
946 
947 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal(),
948           InsertMode, INSERT_VALUES, ADD_VALUES, MatSetValues()
949 @*/
950 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesRow(Mat mat,PetscInt row,const PetscScalar v[])
951 {
952   PetscErrorCode ierr;
953 
954   PetscFunctionBegin;
955   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
956   PetscValidType(mat,1);
957   PetscValidScalarPointer(v,2);
958 #if defined(PETSC_USE_DEBUG)
959   if (mat->insertmode == ADD_VALUES) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add and insert values");
960   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
961 #endif
962   mat->insertmode = INSERT_VALUES;
963 
964   if (mat->assembled) {
965     mat->was_assembled = PETSC_TRUE;
966     mat->assembled     = PETSC_FALSE;
967   }
968   ierr = PetscLogEventBegin(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
969   if (!mat->ops->setvaluesrow) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
970   ierr = (*mat->ops->setvaluesrow)(mat,row,v);CHKERRQ(ierr);
971   ierr = PetscLogEventEnd(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
972   PetscFunctionReturn(0);
973 }
974 
975 #undef __FUNCT__
976 #define __FUNCT__ "MatSetValuesStencil"
977 /*@
978    MatSetValuesStencil - Inserts or adds a block of values into a matrix.
979      Using structured grid indexing
980 
981    Not Collective
982 
983    Input Parameters:
984 +  mat - the matrix
985 .  v - a logically two-dimensional array of values
986 .  m - number of rows being entered
987 .  idxm - grid coordinates (and component number when dof > 1) for matrix rows being entered
988 .  n - number of columns being entered
989 .  idxn - grid coordinates (and component number when dof > 1) for matrix columns being entered
990 -  addv - either ADD_VALUES or INSERT_VALUES, where
991    ADD_VALUES adds values to any existing entries, and
992    INSERT_VALUES replaces existing entries with new values
993 
994    Notes:
995    By default the values, v, are row-oriented and unsorted.
996    See MatSetOption() for other options.
997 
998    Calls to MatSetValuesStencil() with the INSERT_VALUES and ADD_VALUES
999    options cannot be mixed without intervening calls to the assembly
1000    routines.
1001 
1002    The grid coordinates are across the entire grid, not just the local portion
1003 
1004    MatSetValuesStencil() uses 0-based row and column numbers in Fortran
1005    as well as in C.
1006 
1007    For setting/accessing vector values via array coordinates you can use the DAVecGetArray() routine
1008 
1009    In order to use this routine you must either obtain the matrix with DAGetMatrix()
1010    or call MatSetLocalToGlobalMapping() and MatSetStencil() first.
1011 
1012    The columns and rows in the stencil passed in MUST be contained within the
1013    ghost region of the given process as set with DACreateXXX() or MatSetStencil(). For example,
1014    if you create a DA with an overlap of one grid level and on a particular process its first
1015    local nonghost x logical coordinate is 6 (so its first ghost x logical coordinate is 5) the
1016    first i index you can use in your column and row indices in MatSetStencil() is 5.
1017 
1018    In Fortran idxm and idxn should be declared as
1019 $     MatStencil idxm(4,m),idxn(4,n)
1020    and the values inserted using
1021 $    idxm(MatStencil_i,1) = i
1022 $    idxm(MatStencil_j,1) = j
1023 $    idxm(MatStencil_k,1) = k
1024 $    idxm(MatStencil_c,1) = c
1025    etc
1026 
1027    For periodic boundary conditions use negative indices for values to the left (below 0; that are to be
1028    obtained by wrapping values from right edge). For values to the right of the last entry using that index plus one
1029    etc to obtain values that obtained by wrapping the values from the left edge.
1030 
1031    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
1032    a single value per point) you can skip filling those indices.
1033 
1034    Inspired by the structured grid interface to the HYPRE package
1035    (http://www.llnl.gov/CASC/hypre)
1036 
1037    Efficiency Alert:
1038    The routine MatSetValuesBlockedStencil() may offer much better efficiency
1039    for users of block sparse formats (MATSEQBAIJ and MATMPIBAIJ).
1040 
1041    Level: beginner
1042 
1043    Concepts: matrices^putting entries in
1044 
1045 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal()
1046           MatSetValues(), MatSetValuesBlockedStencil(), MatSetStencil(), DAGetMatrix(), DAVecGetArray(), MatStencil
1047 @*/
1048 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesStencil(Mat mat,PetscInt m,const MatStencil idxm[],PetscInt n,const MatStencil idxn[],const PetscScalar v[],InsertMode addv)
1049 {
1050   PetscErrorCode ierr;
1051   PetscInt       j,i,jdxm[128],jdxn[256],dim = mat->stencil.dim,*dims = mat->stencil.dims+1,tmp;
1052   PetscInt       *starts = mat->stencil.starts,*dxm = (PetscInt*)idxm,*dxn = (PetscInt*)idxn,sdim = dim - (1 - (PetscInt)mat->stencil.noc);
1053 
1054   PetscFunctionBegin;
1055   if (!m || !n) PetscFunctionReturn(0); /* no values to insert */
1056   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1057   PetscValidType(mat,1);
1058   PetscValidIntPointer(idxm,3);
1059   PetscValidIntPointer(idxn,5);
1060   PetscValidScalarPointer(v,6);
1061 
1062   if (m > 128) SETERRQ1(PETSC_ERR_SUP,"Can only set 128 rows at a time; trying to set %D",m);
1063   if (n > 256) SETERRQ1(PETSC_ERR_SUP,"Can only set 256 columns at a time; trying to set %D",n);
1064 
1065   for (i=0; i<m; i++) {
1066     for (j=0; j<3-sdim; j++) dxm++;
1067     tmp = *dxm++ - starts[0];
1068     for (j=0; j<dim-1; j++) {
1069       if ((*dxm++ - starts[j+1]) < 0 || tmp < 0) tmp = PETSC_MIN_INT;
1070       else                                       tmp = tmp*dims[j] + *(dxm-1) - starts[j+1];
1071     }
1072     if (mat->stencil.noc) dxm++;
1073     jdxm[i] = tmp;
1074   }
1075   for (i=0; i<n; i++) {
1076     for (j=0; j<3-sdim; j++) dxn++;
1077     tmp = *dxn++ - starts[0];
1078     for (j=0; j<dim-1; j++) {
1079       if ((*dxn++ - starts[j+1]) < 0 || tmp < 0) tmp = PETSC_MIN_INT;
1080       else                                       tmp = tmp*dims[j] + *(dxn-1) - starts[j+1];
1081     }
1082     if (mat->stencil.noc) dxn++;
1083     jdxn[i] = tmp;
1084   }
1085   ierr = MatSetValuesLocal(mat,m,jdxm,n,jdxn,v,addv);CHKERRQ(ierr);
1086   PetscFunctionReturn(0);
1087 }
1088 
1089 #undef __FUNCT__
1090 #define __FUNCT__ "MatSetValuesBlockedStencil"
1091 /*@C
1092    MatSetValuesBlockedStencil - Inserts or adds a block of values into a matrix.
1093      Using structured grid indexing
1094 
1095    Not Collective
1096 
1097    Input Parameters:
1098 +  mat - the matrix
1099 .  v - a logically two-dimensional array of values
1100 .  m - number of rows being entered
1101 .  idxm - grid coordinates for matrix rows being entered
1102 .  n - number of columns being entered
1103 .  idxn - grid coordinates for matrix columns being entered
1104 -  addv - either ADD_VALUES or INSERT_VALUES, where
1105    ADD_VALUES adds values to any existing entries, and
1106    INSERT_VALUES replaces existing entries with new values
1107 
1108    Notes:
1109    By default the values, v, are row-oriented and unsorted.
1110    See MatSetOption() for other options.
1111 
1112    Calls to MatSetValuesBlockedStencil() with the INSERT_VALUES and ADD_VALUES
1113    options cannot be mixed without intervening calls to the assembly
1114    routines.
1115 
1116    The grid coordinates are across the entire grid, not just the local portion
1117 
1118    MatSetValuesBlockedStencil() uses 0-based row and column numbers in Fortran
1119    as well as in C.
1120 
1121    For setting/accessing vector values via array coordinates you can use the DAVecGetArray() routine
1122 
1123    In order to use this routine you must either obtain the matrix with DAGetMatrix()
1124    or call MatSetLocalToGlobalMapping() and MatSetStencil() first.
1125 
1126    The columns and rows in the stencil passed in MUST be contained within the
1127    ghost region of the given process as set with DACreateXXX() or MatSetStencil(). For example,
1128    if you create a DA with an overlap of one grid level and on a particular process its first
1129    local nonghost x logical coordinate is 6 (so its first ghost x logical coordinate is 5) the
1130    first i index you can use in your column and row indices in MatSetStencil() is 5.
1131 
1132    In Fortran idxm and idxn should be declared as
1133 $     MatStencil idxm(4,m),idxn(4,n)
1134    and the values inserted using
1135 $    idxm(MatStencil_i,1) = i
1136 $    idxm(MatStencil_j,1) = j
1137 $    idxm(MatStencil_k,1) = k
1138    etc
1139 
1140    Negative indices may be passed in idxm and idxn, these rows and columns are
1141    simply ignored. This allows easily inserting element stiffness matrices
1142    with homogeneous Dirchlet boundary conditions that you don't want represented
1143    in the matrix.
1144 
1145    Inspired by the structured grid interface to the HYPRE package
1146    (http://www.llnl.gov/CASC/hypre)
1147 
1148    Level: beginner
1149 
1150    Concepts: matrices^putting entries in
1151 
1152 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal()
1153           MatSetValues(), MatSetValuesStencil(), MatSetStencil(), DAGetMatrix(), DAVecGetArray(), MatStencil
1154 @*/
1155 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesBlockedStencil(Mat mat,PetscInt m,const MatStencil idxm[],PetscInt n,const MatStencil idxn[],const PetscScalar v[],InsertMode addv)
1156 {
1157   PetscErrorCode ierr;
1158   PetscInt       j,i,jdxm[128],jdxn[256],dim = mat->stencil.dim,*dims = mat->stencil.dims+1,tmp;
1159   PetscInt       *starts = mat->stencil.starts,*dxm = (PetscInt*)idxm,*dxn = (PetscInt*)idxn,sdim = dim - (1 - (PetscInt)mat->stencil.noc);
1160 
1161   PetscFunctionBegin;
1162   if (!m || !n) PetscFunctionReturn(0); /* no values to insert */
1163   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1164   PetscValidType(mat,1);
1165   PetscValidIntPointer(idxm,3);
1166   PetscValidIntPointer(idxn,5);
1167   PetscValidScalarPointer(v,6);
1168 
1169   if (m > 128) SETERRQ1(PETSC_ERR_SUP,"Can only set 128 rows at a time; trying to set %D",m);
1170   if (n > 128) SETERRQ1(PETSC_ERR_SUP,"Can only set 256 columns at a time; trying to set %D",n);
1171 
1172   for (i=0; i<m; i++) {
1173     for (j=0; j<3-sdim; j++) dxm++;
1174     tmp = *dxm++ - starts[0];
1175     for (j=0; j<sdim-1; j++) {
1176       if ((*dxm++ - starts[j+1]) < 0 || tmp < 0) tmp = PETSC_MIN_INT;
1177       else                                      tmp = tmp*dims[j] + *(dxm-1) - starts[j+1];
1178     }
1179     dxm++;
1180     jdxm[i] = tmp;
1181   }
1182   for (i=0; i<n; i++) {
1183     for (j=0; j<3-sdim; j++) dxn++;
1184     tmp = *dxn++ - starts[0];
1185     for (j=0; j<sdim-1; j++) {
1186       if ((*dxn++ - starts[j+1]) < 0 || tmp < 0) tmp = PETSC_MIN_INT;
1187       else                                       tmp = tmp*dims[j] + *(dxn-1) - starts[j+1];
1188     }
1189     dxn++;
1190     jdxn[i] = tmp;
1191   }
1192   ierr = MatSetValuesBlockedLocal(mat,m,jdxm,n,jdxn,v,addv);CHKERRQ(ierr);
1193   PetscFunctionReturn(0);
1194 }
1195 
1196 #undef __FUNCT__
1197 #define __FUNCT__ "MatSetStencil"
1198 /*@
1199    MatSetStencil - Sets the grid information for setting values into a matrix via
1200         MatSetValuesStencil()
1201 
1202    Not Collective
1203 
1204    Input Parameters:
1205 +  mat - the matrix
1206 .  dim - dimension of the grid 1, 2, or 3
1207 .  dims - number of grid points in x, y, and z direction, including ghost points on your processor
1208 .  starts - starting point of ghost nodes on your processor in x, y, and z direction
1209 -  dof - number of degrees of freedom per node
1210 
1211 
1212    Inspired by the structured grid interface to the HYPRE package
1213    (www.llnl.gov/CASC/hyper)
1214 
1215    For matrices generated with DAGetMatrix() this routine is automatically called and so not needed by the
1216    user.
1217 
1218    Level: beginner
1219 
1220    Concepts: matrices^putting entries in
1221 
1222 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal()
1223           MatSetValues(), MatSetValuesBlockedStencil(), MatSetValuesStencil()
1224 @*/
1225 PetscErrorCode PETSCMAT_DLLEXPORT MatSetStencil(Mat mat,PetscInt dim,const PetscInt dims[],const PetscInt starts[],PetscInt dof)
1226 {
1227   PetscInt i;
1228 
1229   PetscFunctionBegin;
1230   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1231   PetscValidIntPointer(dims,3);
1232   PetscValidIntPointer(starts,4);
1233 
1234   mat->stencil.dim = dim + (dof > 1);
1235   for (i=0; i<dim; i++) {
1236     mat->stencil.dims[i]   = dims[dim-i-1];      /* copy the values in backwards */
1237     mat->stencil.starts[i] = starts[dim-i-1];
1238   }
1239   mat->stencil.dims[dim]   = dof;
1240   mat->stencil.starts[dim] = 0;
1241   mat->stencil.noc         = (PetscTruth)(dof == 1);
1242   PetscFunctionReturn(0);
1243 }
1244 
1245 #undef __FUNCT__
1246 #define __FUNCT__ "MatSetValuesBlocked"
1247 /*@
1248    MatSetValuesBlocked - Inserts or adds a block of values into a matrix.
1249 
1250    Not Collective
1251 
1252    Input Parameters:
1253 +  mat - the matrix
1254 .  v - a logically two-dimensional array of values
1255 .  m, idxm - the number of block rows and their global block indices
1256 .  n, idxn - the number of block columns and their global block indices
1257 -  addv - either ADD_VALUES or INSERT_VALUES, where
1258    ADD_VALUES adds values to any existing entries, and
1259    INSERT_VALUES replaces existing entries with new values
1260 
1261    Notes:
1262    The m and n count the NUMBER of blocks in the row direction and column direction,
1263    NOT the total number of rows/columns; for example, if the block size is 2 and
1264    you are passing in values for rows 2,3,4,5  then m would be 2 (not 4).
1265 
1266    By default the values, v, are row-oriented and unsorted. So the layout of
1267    v is the same as for MatSetValues(). See MatSetOption() for other options.
1268 
1269    Calls to MatSetValuesBlocked() with the INSERT_VALUES and ADD_VALUES
1270    options cannot be mixed without intervening calls to the assembly
1271    routines.
1272 
1273    MatSetValuesBlocked() uses 0-based row and column numbers in Fortran
1274    as well as in C.
1275 
1276    Negative indices may be passed in idxm and idxn, these rows and columns are
1277    simply ignored. This allows easily inserting element stiffness matrices
1278    with homogeneous Dirchlet boundary conditions that you don't want represented
1279    in the matrix.
1280 
1281    Each time an entry is set within a sparse matrix via MatSetValues(),
1282    internal searching must be done to determine where to place the the
1283    data in the matrix storage space.  By instead inserting blocks of
1284    entries via MatSetValuesBlocked(), the overhead of matrix assembly is
1285    reduced.
1286 
1287    Example:
1288 $   Suppose m=n=2 and block size(bs) = 2 The matrix is
1289 $
1290 $   1  2  | 3  4
1291 $   5  6  | 7  8
1292 $   - - - | - - -
1293 $   9  10 | 11 12
1294 $   13 14 | 15 16
1295 $
1296 $   v[] should be passed in like
1297 $   v[] = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16]
1298 
1299    Restrictions:
1300    MatSetValuesBlocked() is currently supported only for the BAIJ and SBAIJ formats
1301 
1302    Level: intermediate
1303 
1304    Concepts: matrices^putting entries in blocked
1305 
1306 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValues(), MatSetValuesBlockedLocal()
1307 @*/
1308 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesBlocked(Mat mat,PetscInt m,const PetscInt idxm[],PetscInt n,const PetscInt idxn[],const PetscScalar v[],InsertMode addv)
1309 {
1310   PetscErrorCode ierr;
1311 
1312   PetscFunctionBegin;
1313   if (!m || !n) PetscFunctionReturn(0); /* no values to insert */
1314   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1315   PetscValidType(mat,1);
1316   PetscValidIntPointer(idxm,3);
1317   PetscValidIntPointer(idxn,5);
1318   PetscValidScalarPointer(v,6);
1319   ierr = MatPreallocated(mat);CHKERRQ(ierr);
1320   if (mat->insertmode == NOT_SET_VALUES) {
1321     mat->insertmode = addv;
1322   }
1323 #if defined(PETSC_USE_DEBUG)
1324   else if (mat->insertmode != addv) {
1325     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
1326   }
1327   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1328 #endif
1329 
1330   if (mat->assembled) {
1331     mat->was_assembled = PETSC_TRUE;
1332     mat->assembled     = PETSC_FALSE;
1333   }
1334   ierr = PetscLogEventBegin(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
1335   if (!mat->ops->setvaluesblocked) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
1336   ierr = (*mat->ops->setvaluesblocked)(mat,m,idxm,n,idxn,v,addv);CHKERRQ(ierr);
1337   ierr = PetscLogEventEnd(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
1338   PetscFunctionReturn(0);
1339 }
1340 
1341 #undef __FUNCT__
1342 #define __FUNCT__ "MatGetValues"
1343 /*@
1344    MatGetValues - Gets a block of values from a matrix.
1345 
1346    Not Collective; currently only returns a local block
1347 
1348    Input Parameters:
1349 +  mat - the matrix
1350 .  v - a logically two-dimensional array for storing the values
1351 .  m, idxm - the number of rows and their global indices
1352 -  n, idxn - the number of columns and their global indices
1353 
1354    Notes:
1355    The user must allocate space (m*n PetscScalars) for the values, v.
1356    The values, v, are then returned in a row-oriented format,
1357    analogous to that used by default in MatSetValues().
1358 
1359    MatGetValues() uses 0-based row and column numbers in
1360    Fortran as well as in C.
1361 
1362    MatGetValues() requires that the matrix has been assembled
1363    with MatAssemblyBegin()/MatAssemblyEnd().  Thus, calls to
1364    MatSetValues() and MatGetValues() CANNOT be made in succession
1365    without intermediate matrix assembly.
1366 
1367    Negative row or column indices will be ignored and those locations in v[] will be
1368    left unchanged.
1369 
1370    Level: advanced
1371 
1372    Concepts: matrices^accessing values
1373 
1374 .seealso: MatGetRow(), MatGetSubMatrices(), MatSetValues()
1375 @*/
1376 PetscErrorCode PETSCMAT_DLLEXPORT MatGetValues(Mat mat,PetscInt m,const PetscInt idxm[],PetscInt n,const PetscInt idxn[],PetscScalar v[])
1377 {
1378   PetscErrorCode ierr;
1379 
1380   PetscFunctionBegin;
1381   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1382   PetscValidType(mat,1);
1383   PetscValidIntPointer(idxm,3);
1384   PetscValidIntPointer(idxn,5);
1385   PetscValidScalarPointer(v,6);
1386   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1387   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1388   if (!mat->ops->getvalues) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
1389   ierr = MatPreallocated(mat);CHKERRQ(ierr);
1390 
1391   ierr = PetscLogEventBegin(MAT_GetValues,mat,0,0,0);CHKERRQ(ierr);
1392   ierr = (*mat->ops->getvalues)(mat,m,idxm,n,idxn,v);CHKERRQ(ierr);
1393   ierr = PetscLogEventEnd(MAT_GetValues,mat,0,0,0);CHKERRQ(ierr);
1394   PetscFunctionReturn(0);
1395 }
1396 
1397 #undef __FUNCT__
1398 #define __FUNCT__ "MatSetLocalToGlobalMapping"
1399 /*@
1400    MatSetLocalToGlobalMapping - Sets a local-to-global numbering for use by
1401    the routine MatSetValuesLocal() to allow users to insert matrix entries
1402    using a local (per-processor) numbering.
1403 
1404    Not Collective
1405 
1406    Input Parameters:
1407 +  x - the matrix
1408 -  mapping - mapping created with ISLocalToGlobalMappingCreate()
1409              or ISLocalToGlobalMappingCreateIS()
1410 
1411    Level: intermediate
1412 
1413    Concepts: matrices^local to global mapping
1414    Concepts: local to global mapping^for matrices
1415 
1416 .seealso:  MatAssemblyBegin(), MatAssemblyEnd(), MatSetValues(), MatSetValuesLocal()
1417 @*/
1418 PetscErrorCode PETSCMAT_DLLEXPORT MatSetLocalToGlobalMapping(Mat x,ISLocalToGlobalMapping mapping)
1419 {
1420   PetscErrorCode ierr;
1421   PetscFunctionBegin;
1422   PetscValidHeaderSpecific(x,MAT_COOKIE,1);
1423   PetscValidType(x,1);
1424   PetscValidHeaderSpecific(mapping,IS_LTOGM_COOKIE,2);
1425   if (x->mapping) {
1426     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Mapping already set for matrix");
1427   }
1428   ierr = MatPreallocated(x);CHKERRQ(ierr);
1429 
1430   if (x->ops->setlocaltoglobalmapping) {
1431     ierr = (*x->ops->setlocaltoglobalmapping)(x,mapping);CHKERRQ(ierr);
1432   } else {
1433     ierr = PetscObjectReference((PetscObject)mapping);CHKERRQ(ierr);
1434     if (x->mapping) { ierr = ISLocalToGlobalMappingDestroy(x->mapping);CHKERRQ(ierr); }
1435     x->mapping = mapping;
1436   }
1437   PetscFunctionReturn(0);
1438 }
1439 
1440 #undef __FUNCT__
1441 #define __FUNCT__ "MatSetLocalToGlobalMappingBlock"
1442 /*@
1443    MatSetLocalToGlobalMappingBlock - Sets a local-to-global numbering for use
1444    by the routine MatSetValuesBlockedLocal() to allow users to insert matrix
1445    entries using a local (per-processor) numbering.
1446 
1447    Not Collective
1448 
1449    Input Parameters:
1450 +  x - the matrix
1451 -  mapping - mapping created with ISLocalToGlobalMappingCreate() or
1452              ISLocalToGlobalMappingCreateIS()
1453 
1454    Level: intermediate
1455 
1456    Concepts: matrices^local to global mapping blocked
1457    Concepts: local to global mapping^for matrices, blocked
1458 
1459 .seealso:  MatAssemblyBegin(), MatAssemblyEnd(), MatSetValues(), MatSetValuesBlockedLocal(),
1460            MatSetValuesBlocked(), MatSetValuesLocal()
1461 @*/
1462 PetscErrorCode PETSCMAT_DLLEXPORT MatSetLocalToGlobalMappingBlock(Mat x,ISLocalToGlobalMapping mapping)
1463 {
1464   PetscErrorCode ierr;
1465   PetscFunctionBegin;
1466   PetscValidHeaderSpecific(x,MAT_COOKIE,1);
1467   PetscValidType(x,1);
1468   PetscValidHeaderSpecific(mapping,IS_LTOGM_COOKIE,2);
1469   if (x->bmapping) {
1470     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Mapping already set for matrix");
1471   }
1472   ierr = PetscObjectReference((PetscObject)mapping);CHKERRQ(ierr);
1473   if (x->bmapping) { ierr = ISLocalToGlobalMappingDestroy(x->mapping);CHKERRQ(ierr); }
1474   x->bmapping = mapping;
1475   PetscFunctionReturn(0);
1476 }
1477 
1478 #undef __FUNCT__
1479 #define __FUNCT__ "MatSetValuesLocal"
1480 /*@
1481    MatSetValuesLocal - Inserts or adds values into certain locations of a matrix,
1482    using a local ordering of the nodes.
1483 
1484    Not Collective
1485 
1486    Input Parameters:
1487 +  x - the matrix
1488 .  nrow, irow - number of rows and their local indices
1489 .  ncol, icol - number of columns and their local indices
1490 .  y -  a logically two-dimensional array of values
1491 -  addv - either INSERT_VALUES or ADD_VALUES, where
1492    ADD_VALUES adds values to any existing entries, and
1493    INSERT_VALUES replaces existing entries with new values
1494 
1495    Notes:
1496    Before calling MatSetValuesLocal(), the user must first set the
1497    local-to-global mapping by calling MatSetLocalToGlobalMapping().
1498 
1499    Calls to MatSetValuesLocal() with the INSERT_VALUES and ADD_VALUES
1500    options cannot be mixed without intervening calls to the assembly
1501    routines.
1502 
1503    These values may be cached, so MatAssemblyBegin() and MatAssemblyEnd()
1504    MUST be called after all calls to MatSetValuesLocal() have been completed.
1505 
1506    Level: intermediate
1507 
1508    Concepts: matrices^putting entries in with local numbering
1509 
1510 .seealso:  MatAssemblyBegin(), MatAssemblyEnd(), MatSetValues(), MatSetLocalToGlobalMapping(),
1511            MatSetValueLocal()
1512 @*/
1513 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesLocal(Mat mat,PetscInt nrow,const PetscInt irow[],PetscInt ncol,const PetscInt icol[],const PetscScalar y[],InsertMode addv)
1514 {
1515   PetscErrorCode ierr;
1516   PetscInt       irowm[2048],icolm[2048];
1517 
1518   PetscFunctionBegin;
1519   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1520   PetscValidType(mat,1);
1521   PetscValidIntPointer(irow,3);
1522   PetscValidIntPointer(icol,5);
1523   PetscValidScalarPointer(y,6);
1524   ierr = MatPreallocated(mat);CHKERRQ(ierr);
1525   if (mat->insertmode == NOT_SET_VALUES) {
1526     mat->insertmode = addv;
1527   }
1528 #if defined(PETSC_USE_DEBUG)
1529   else if (mat->insertmode != addv) {
1530     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
1531   }
1532   if (!mat->ops->setvalueslocal && (nrow > 2048 || ncol > 2048)) {
1533     SETERRQ2(PETSC_ERR_SUP,"Number column/row indices must be <= 2048: are %D %D",nrow,ncol);
1534   }
1535   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1536 #endif
1537 
1538   if (mat->assembled) {
1539     mat->was_assembled = PETSC_TRUE;
1540     mat->assembled     = PETSC_FALSE;
1541   }
1542   ierr = PetscLogEventBegin(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
1543   if (!mat->ops->setvalueslocal) {
1544     ierr = ISLocalToGlobalMappingApply(mat->mapping,nrow,irow,irowm);CHKERRQ(ierr);
1545     ierr = ISLocalToGlobalMappingApply(mat->mapping,ncol,icol,icolm);CHKERRQ(ierr);
1546     ierr = (*mat->ops->setvalues)(mat,nrow,irowm,ncol,icolm,y,addv);CHKERRQ(ierr);
1547   } else {
1548     ierr = (*mat->ops->setvalueslocal)(mat,nrow,irow,ncol,icol,y,addv);CHKERRQ(ierr);
1549   }
1550   mat->same_nonzero = PETSC_FALSE;
1551   ierr = PetscLogEventEnd(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
1552   PetscFunctionReturn(0);
1553 }
1554 
1555 #undef __FUNCT__
1556 #define __FUNCT__ "MatSetValuesBlockedLocal"
1557 /*@
1558    MatSetValuesBlockedLocal - Inserts or adds values into certain locations of a matrix,
1559    using a local ordering of the nodes a block at a time.
1560 
1561    Not Collective
1562 
1563    Input Parameters:
1564 +  x - the matrix
1565 .  nrow, irow - number of rows and their local indices
1566 .  ncol, icol - number of columns and their local indices
1567 .  y -  a logically two-dimensional array of values
1568 -  addv - either INSERT_VALUES or ADD_VALUES, where
1569    ADD_VALUES adds values to any existing entries, and
1570    INSERT_VALUES replaces existing entries with new values
1571 
1572    Notes:
1573    Before calling MatSetValuesBlockedLocal(), the user must first set the
1574    local-to-global mapping by calling MatSetLocalToGlobalMappingBlock(),
1575    where the mapping MUST be set for matrix blocks, not for matrix elements.
1576 
1577    Calls to MatSetValuesBlockedLocal() with the INSERT_VALUES and ADD_VALUES
1578    options cannot be mixed without intervening calls to the assembly
1579    routines.
1580 
1581    These values may be cached, so MatAssemblyBegin() and MatAssemblyEnd()
1582    MUST be called after all calls to MatSetValuesBlockedLocal() have been completed.
1583 
1584    Level: intermediate
1585 
1586    Concepts: matrices^putting blocked values in with local numbering
1587 
1588 .seealso:  MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesLocal(), MatSetLocalToGlobalMappingBlock(), MatSetValuesBlocked()
1589 @*/
1590 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesBlockedLocal(Mat mat,PetscInt nrow,const PetscInt irow[],PetscInt ncol,const PetscInt icol[],const PetscScalar y[],InsertMode addv)
1591 {
1592   PetscErrorCode ierr;
1593   PetscInt       irowm[2048],icolm[2048];
1594 
1595   PetscFunctionBegin;
1596   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1597   PetscValidType(mat,1);
1598   PetscValidIntPointer(irow,3);
1599   PetscValidIntPointer(icol,5);
1600   PetscValidScalarPointer(y,6);
1601   ierr = MatPreallocated(mat);CHKERRQ(ierr);
1602   if (mat->insertmode == NOT_SET_VALUES) {
1603     mat->insertmode = addv;
1604   }
1605 #if defined(PETSC_USE_DEBUG)
1606   else if (mat->insertmode != addv) {
1607     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
1608   }
1609   if (!mat->bmapping) {
1610     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Local to global never set with MatSetLocalToGlobalMappingBlock()");
1611   }
1612   if (nrow > 2048 || ncol > 2048) {
1613     SETERRQ2(PETSC_ERR_SUP,"Number column/row indices must be <= 2048: are %D %D",nrow,ncol);
1614   }
1615   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1616 #endif
1617 
1618   if (mat->assembled) {
1619     mat->was_assembled = PETSC_TRUE;
1620     mat->assembled     = PETSC_FALSE;
1621   }
1622   ierr = PetscLogEventBegin(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
1623   ierr = ISLocalToGlobalMappingApply(mat->bmapping,nrow,irow,irowm);CHKERRQ(ierr);
1624   ierr = ISLocalToGlobalMappingApply(mat->bmapping,ncol,icol,icolm);CHKERRQ(ierr);
1625   ierr = (*mat->ops->setvaluesblocked)(mat,nrow,irowm,ncol,icolm,y,addv);CHKERRQ(ierr);
1626   ierr = PetscLogEventEnd(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
1627   PetscFunctionReturn(0);
1628 }
1629 
1630 /* --------------------------------------------------------*/
1631 #undef __FUNCT__
1632 #define __FUNCT__ "MatMult"
1633 /*@
1634    MatMult - Computes the matrix-vector product, y = Ax.
1635 
1636    Collective on Mat and Vec
1637 
1638    Input Parameters:
1639 +  mat - the matrix
1640 -  x   - the vector to be multiplied
1641 
1642    Output Parameters:
1643 .  y - the result
1644 
1645    Notes:
1646    The vectors x and y cannot be the same.  I.e., one cannot
1647    call MatMult(A,y,y).
1648 
1649    Level: beginner
1650 
1651    Concepts: matrix-vector product
1652 
1653 .seealso: MatMultTranspose(), MatMultAdd(), MatMultTransposeAdd()
1654 @*/
1655 PetscErrorCode PETSCMAT_DLLEXPORT MatMult(Mat mat,Vec x,Vec y)
1656 {
1657   PetscErrorCode ierr;
1658 
1659   PetscFunctionBegin;
1660   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1661   PetscValidType(mat,1);
1662   PetscValidHeaderSpecific(x,VEC_COOKIE,2);
1663   PetscValidHeaderSpecific(y,VEC_COOKIE,3);
1664 
1665   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1666   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1667   if (x == y) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"x and y must be different vectors");
1668 #ifndef PETSC_HAVE_CONSTRAINTS
1669   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);
1670   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);
1671   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);
1672 #endif
1673   ierr = MatPreallocated(mat);CHKERRQ(ierr);
1674 
1675   if (mat->nullsp) {
1676     ierr = MatNullSpaceRemove(mat->nullsp,x,&x);CHKERRQ(ierr);
1677   }
1678 
1679   if (!mat->ops->mult) SETERRQ(PETSC_ERR_SUP,"This matrix type does not have a multiply defined");
1680   ierr = PetscLogEventBegin(MAT_Mult,mat,x,y,0);CHKERRQ(ierr);
1681   ierr = (*mat->ops->mult)(mat,x,y);CHKERRQ(ierr);
1682   ierr = PetscLogEventEnd(MAT_Mult,mat,x,y,0);CHKERRQ(ierr);
1683 
1684   if (mat->nullsp) {
1685     ierr = MatNullSpaceRemove(mat->nullsp,y,PETSC_NULL);CHKERRQ(ierr);
1686   }
1687   ierr = PetscObjectStateIncrease((PetscObject)y);CHKERRQ(ierr);
1688   PetscFunctionReturn(0);
1689 }
1690 
1691 #undef __FUNCT__
1692 #define __FUNCT__ "MatMultTranspose"
1693 /*@
1694    MatMultTranspose - Computes matrix transpose times a vector.
1695 
1696    Collective on Mat and Vec
1697 
1698    Input Parameters:
1699 +  mat - the matrix
1700 -  x   - the vector to be multilplied
1701 
1702    Output Parameters:
1703 .  y - the result
1704 
1705    Notes:
1706    The vectors x and y cannot be the same.  I.e., one cannot
1707    call MatMultTranspose(A,y,y).
1708 
1709    Level: beginner
1710 
1711    Concepts: matrix vector product^transpose
1712 
1713 .seealso: MatMult(), MatMultAdd(), MatMultTransposeAdd()
1714 @*/
1715 PetscErrorCode PETSCMAT_DLLEXPORT MatMultTranspose(Mat mat,Vec x,Vec y)
1716 {
1717   PetscErrorCode ierr;
1718 
1719   PetscFunctionBegin;
1720   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1721   PetscValidType(mat,1);
1722   PetscValidHeaderSpecific(x,VEC_COOKIE,2);
1723   PetscValidHeaderSpecific(y,VEC_COOKIE,3);
1724 
1725   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1726   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1727   if (x == y) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"x and y must be different vectors");
1728 #ifndef PETSC_HAVE_CONSTRAINTS
1729   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);
1730   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);
1731 #endif
1732   ierr = MatPreallocated(mat);CHKERRQ(ierr);
1733 
1734   if (!mat->ops->multtranspose) SETERRQ(PETSC_ERR_SUP,"This matrix type does not have a multiply tranpose defined");
1735   ierr = PetscLogEventBegin(MAT_MultTranspose,mat,x,y,0);CHKERRQ(ierr);
1736   ierr = (*mat->ops->multtranspose)(mat,x,y);CHKERRQ(ierr);
1737   ierr = PetscLogEventEnd(MAT_MultTranspose,mat,x,y,0);CHKERRQ(ierr);
1738   ierr = PetscObjectStateIncrease((PetscObject)y);CHKERRQ(ierr);
1739   PetscFunctionReturn(0);
1740 }
1741 
1742 #undef __FUNCT__
1743 #define __FUNCT__ "MatMultAdd"
1744 /*@
1745     MatMultAdd -  Computes v3 = v2 + A * v1.
1746 
1747     Collective on Mat and Vec
1748 
1749     Input Parameters:
1750 +   mat - the matrix
1751 -   v1, v2 - the vectors
1752 
1753     Output Parameters:
1754 .   v3 - the result
1755 
1756     Notes:
1757     The vectors v1 and v3 cannot be the same.  I.e., one cannot
1758     call MatMultAdd(A,v1,v2,v1).
1759 
1760     Level: beginner
1761 
1762     Concepts: matrix vector product^addition
1763 
1764 .seealso: MatMultTranspose(), MatMult(), MatMultTransposeAdd()
1765 @*/
1766 PetscErrorCode PETSCMAT_DLLEXPORT MatMultAdd(Mat mat,Vec v1,Vec v2,Vec v3)
1767 {
1768   PetscErrorCode ierr;
1769 
1770   PetscFunctionBegin;
1771   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1772   PetscValidType(mat,1);
1773   PetscValidHeaderSpecific(v1,VEC_COOKIE,2);
1774   PetscValidHeaderSpecific(v2,VEC_COOKIE,3);
1775   PetscValidHeaderSpecific(v3,VEC_COOKIE,4);
1776 
1777   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1778   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1779   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);
1780   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);
1781   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);
1782   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);
1783   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);
1784   if (v1 == v3) SETERRQ(PETSC_ERR_ARG_IDN,"v1 and v3 must be different vectors");
1785   ierr = MatPreallocated(mat);CHKERRQ(ierr);
1786 
1787   ierr = PetscLogEventBegin(MAT_MultAdd,mat,v1,v2,v3);CHKERRQ(ierr);
1788   ierr = (*mat->ops->multadd)(mat,v1,v2,v3);CHKERRQ(ierr);
1789   ierr = PetscLogEventEnd(MAT_MultAdd,mat,v1,v2,v3);CHKERRQ(ierr);
1790   ierr = PetscObjectStateIncrease((PetscObject)v3);CHKERRQ(ierr);
1791   PetscFunctionReturn(0);
1792 }
1793 
1794 #undef __FUNCT__
1795 #define __FUNCT__ "MatMultTransposeAdd"
1796 /*@
1797    MatMultTransposeAdd - Computes v3 = v2 + A' * v1.
1798 
1799    Collective on Mat and Vec
1800 
1801    Input Parameters:
1802 +  mat - the matrix
1803 -  v1, v2 - the vectors
1804 
1805    Output Parameters:
1806 .  v3 - the result
1807 
1808    Notes:
1809    The vectors v1 and v3 cannot be the same.  I.e., one cannot
1810    call MatMultTransposeAdd(A,v1,v2,v1).
1811 
1812    Level: beginner
1813 
1814    Concepts: matrix vector product^transpose and addition
1815 
1816 .seealso: MatMultTranspose(), MatMultAdd(), MatMult()
1817 @*/
1818 PetscErrorCode PETSCMAT_DLLEXPORT MatMultTransposeAdd(Mat mat,Vec v1,Vec v2,Vec v3)
1819 {
1820   PetscErrorCode ierr;
1821 
1822   PetscFunctionBegin;
1823   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1824   PetscValidType(mat,1);
1825   PetscValidHeaderSpecific(v1,VEC_COOKIE,2);
1826   PetscValidHeaderSpecific(v2,VEC_COOKIE,3);
1827   PetscValidHeaderSpecific(v3,VEC_COOKIE,4);
1828 
1829   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1830   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1831   if (!mat->ops->multtransposeadd) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
1832   if (v1 == v3) SETERRQ(PETSC_ERR_ARG_IDN,"v1 and v3 must be different vectors");
1833   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);
1834   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);
1835   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);
1836   ierr = MatPreallocated(mat);CHKERRQ(ierr);
1837 
1838   ierr = PetscLogEventBegin(MAT_MultTransposeAdd,mat,v1,v2,v3);CHKERRQ(ierr);
1839   ierr = (*mat->ops->multtransposeadd)(mat,v1,v2,v3);CHKERRQ(ierr);
1840   ierr = PetscLogEventEnd(MAT_MultTransposeAdd,mat,v1,v2,v3);CHKERRQ(ierr);
1841   ierr = PetscObjectStateIncrease((PetscObject)v3);CHKERRQ(ierr);
1842   PetscFunctionReturn(0);
1843 }
1844 
1845 #undef __FUNCT__
1846 #define __FUNCT__ "MatMultConstrained"
1847 /*@
1848    MatMultConstrained - The inner multiplication routine for a
1849    constrained matrix P^T A P.
1850 
1851    Collective on Mat and Vec
1852 
1853    Input Parameters:
1854 +  mat - the matrix
1855 -  x   - the vector to be multilplied
1856 
1857    Output Parameters:
1858 .  y - the result
1859 
1860    Notes:
1861    The vectors x and y cannot be the same.  I.e., one cannot
1862    call MatMult(A,y,y).
1863 
1864    Level: beginner
1865 
1866 .keywords: matrix, multiply, matrix-vector product, constraint
1867 .seealso: MatMult(), MatMultTrans(), MatMultAdd(), MatMultTransAdd()
1868 @*/
1869 PetscErrorCode PETSCMAT_DLLEXPORT MatMultConstrained(Mat mat,Vec x,Vec y)
1870 {
1871   PetscErrorCode ierr;
1872 
1873   PetscFunctionBegin;
1874   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1875   PetscValidHeaderSpecific(x,VEC_COOKIE,2);
1876   PetscValidHeaderSpecific(y,VEC_COOKIE,3);
1877   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1878   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1879   if (x == y) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"x and y must be different vectors");
1880   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);
1881   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);
1882   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);
1883 
1884   ierr = PetscLogEventBegin(MAT_MultConstrained,mat,x,y,0);CHKERRQ(ierr);
1885   ierr = (*mat->ops->multconstrained)(mat,x,y);CHKERRQ(ierr);
1886   ierr = PetscLogEventEnd(MAT_MultConstrained,mat,x,y,0);CHKERRQ(ierr);
1887   ierr = PetscObjectStateIncrease((PetscObject)y);CHKERRQ(ierr);
1888 
1889   PetscFunctionReturn(0);
1890 }
1891 
1892 #undef __FUNCT__
1893 #define __FUNCT__ "MatMultTransposeConstrained"
1894 /*@
1895    MatMultTransposeConstrained - The inner multiplication routine for a
1896    constrained matrix P^T A^T P.
1897 
1898    Collective on Mat and Vec
1899 
1900    Input Parameters:
1901 +  mat - the matrix
1902 -  x   - the vector to be multilplied
1903 
1904    Output Parameters:
1905 .  y - the result
1906 
1907    Notes:
1908    The vectors x and y cannot be the same.  I.e., one cannot
1909    call MatMult(A,y,y).
1910 
1911    Level: beginner
1912 
1913 .keywords: matrix, multiply, matrix-vector product, constraint
1914 .seealso: MatMult(), MatMultTrans(), MatMultAdd(), MatMultTransAdd()
1915 @*/
1916 PetscErrorCode PETSCMAT_DLLEXPORT MatMultTransposeConstrained(Mat mat,Vec x,Vec y)
1917 {
1918   PetscErrorCode ierr;
1919 
1920   PetscFunctionBegin;
1921   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
1922   PetscValidHeaderSpecific(x,VEC_COOKIE,2);
1923   PetscValidHeaderSpecific(y,VEC_COOKIE,3);
1924   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1925   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1926   if (x == y) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"x and y must be different vectors");
1927   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);
1928   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);
1929 
1930   ierr = PetscLogEventBegin(MAT_MultConstrained,mat,x,y,0);CHKERRQ(ierr);
1931   ierr = (*mat->ops->multtransposeconstrained)(mat,x,y);CHKERRQ(ierr);
1932   ierr = PetscLogEventEnd(MAT_MultConstrained,mat,x,y,0);CHKERRQ(ierr);
1933   ierr = PetscObjectStateIncrease((PetscObject)y);CHKERRQ(ierr);
1934 
1935   PetscFunctionReturn(0);
1936 }
1937 /* ------------------------------------------------------------*/
1938 #undef __FUNCT__
1939 #define __FUNCT__ "MatGetInfo"
1940 /*@
1941    MatGetInfo - Returns information about matrix storage (number of
1942    nonzeros, memory, etc.).
1943 
1944    Collective on Mat if MAT_GLOBAL_MAX or MAT_GLOBAL_SUM is used
1945    as the flag
1946 
1947    Input Parameters:
1948 .  mat - the matrix
1949 
1950    Output Parameters:
1951 +  flag - flag indicating the type of parameters to be returned
1952    (MAT_LOCAL - local matrix, MAT_GLOBAL_MAX - maximum over all processors,
1953    MAT_GLOBAL_SUM - sum over all processors)
1954 -  info - matrix information context
1955 
1956    Notes:
1957    The MatInfo context contains a variety of matrix data, including
1958    number of nonzeros allocated and used, number of mallocs during
1959    matrix assembly, etc.  Additional information for factored matrices
1960    is provided (such as the fill ratio, number of mallocs during
1961    factorization, etc.).  Much of this info is printed to PETSC_STDOUT
1962    when using the runtime options
1963 $       -info -mat_view_info
1964 
1965    Example for C/C++ Users:
1966    See the file ${PETSC_DIR}/include/petscmat.h for a complete list of
1967    data within the MatInfo context.  For example,
1968 .vb
1969       MatInfo info;
1970       Mat     A;
1971       double  mal, nz_a, nz_u;
1972 
1973       MatGetInfo(A,MAT_LOCAL,&info);
1974       mal  = info.mallocs;
1975       nz_a = info.nz_allocated;
1976 .ve
1977 
1978    Example for Fortran Users:
1979    Fortran users should declare info as a double precision
1980    array of dimension MAT_INFO_SIZE, and then extract the parameters
1981    of interest.  See the file ${PETSC_DIR}/include/finclude/petscmat.h
1982    a complete list of parameter names.
1983 .vb
1984       double  precision info(MAT_INFO_SIZE)
1985       double  precision mal, nz_a
1986       Mat     A
1987       integer ierr
1988 
1989       call MatGetInfo(A,MAT_LOCAL,info,ierr)
1990       mal = info(MAT_INFO_MALLOCS)
1991       nz_a = info(MAT_INFO_NZ_ALLOCATED)
1992 .ve
1993 
1994     Level: intermediate
1995 
1996     Concepts: matrices^getting information on
1997 
1998 @*/
1999 PetscErrorCode PETSCMAT_DLLEXPORT MatGetInfo(Mat mat,MatInfoType flag,MatInfo *info)
2000 {
2001   PetscErrorCode ierr;
2002 
2003   PetscFunctionBegin;
2004   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2005   PetscValidType(mat,1);
2006   PetscValidPointer(info,3);
2007   if (!mat->ops->getinfo) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2008   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2009   ierr = (*mat->ops->getinfo)(mat,flag,info);CHKERRQ(ierr);
2010   PetscFunctionReturn(0);
2011 }
2012 
2013 /* ----------------------------------------------------------*/
2014 #undef __FUNCT__
2015 #define __FUNCT__ "MatILUDTFactor"
2016 /*@C
2017    MatILUDTFactor - Performs a drop tolerance ILU factorization.
2018 
2019    Collective on Mat
2020 
2021    Input Parameters:
2022 +  mat - the matrix
2023 .  row - row permutation
2024 .  col - column permutation
2025 -  info - information about the factorization to be done
2026 
2027    Output Parameters:
2028 .  fact - the factored matrix
2029 
2030    Level: developer
2031 
2032    Notes:
2033    Most users should employ the simplified KSP interface for linear solvers
2034    instead of working directly with matrix algebra routines such as this.
2035    See, e.g., KSPCreate().
2036 
2037    This is currently only supported for the SeqAIJ matrix format using code
2038    from Yousef Saad's SPARSEKIT2  package (translated to C with f2c) and/or
2039    Matlab. SPARSEKIT2 is copyrighted by Yousef Saad with the GNU copyright
2040    and thus can be distributed with PETSc.
2041 
2042     Concepts: matrices^ILUDT factorization
2043 
2044 .seealso: MatLUFactorSymbolic(), MatLUFactorNumeric(), MatCholeskyFactor(), MatFactorInfo
2045 @*/
2046 PetscErrorCode PETSCMAT_DLLEXPORT MatILUDTFactor(Mat mat,IS row,IS col,MatFactorInfo *info,Mat *fact)
2047 {
2048   PetscErrorCode ierr;
2049 
2050   PetscFunctionBegin;
2051   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2052   PetscValidType(mat,1);
2053   if (row) PetscValidHeaderSpecific(row,IS_COOKIE,2);
2054   if (col) PetscValidHeaderSpecific(col,IS_COOKIE,3);
2055   PetscValidPointer(info,4);
2056   PetscValidPointer(fact,5);
2057   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2058   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2059   if (!mat->ops->iludtfactor) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2060   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2061   ierr = PetscLogEventBegin(MAT_ILUFactor,mat,row,col,0);CHKERRQ(ierr);
2062   ierr = (*mat->ops->iludtfactor)(mat,row,col,info,fact);CHKERRQ(ierr);
2063   ierr = PetscLogEventEnd(MAT_ILUFactor,mat,row,col,0);CHKERRQ(ierr);
2064   ierr = PetscObjectStateIncrease((PetscObject)*fact);CHKERRQ(ierr);
2065 
2066   PetscFunctionReturn(0);
2067 }
2068 
2069 #undef __FUNCT__
2070 #define __FUNCT__ "MatLUFactor"
2071 /*@
2072    MatLUFactor - Performs in-place LU factorization of matrix.
2073 
2074    Collective on Mat
2075 
2076    Input Parameters:
2077 +  mat - the matrix
2078 .  row - row permutation
2079 .  col - column permutation
2080 -  info - options for factorization, includes
2081 $          fill - expected fill as ratio of original fill.
2082 $          dtcol - pivot tolerance (0 no pivot, 1 full column pivoting)
2083 $                   Run with the option -info to determine an optimal value to use
2084 
2085    Notes:
2086    Most users should employ the simplified KSP interface for linear solvers
2087    instead of working directly with matrix algebra routines such as this.
2088    See, e.g., KSPCreate().
2089 
2090    This changes the state of the matrix to a factored matrix; it cannot be used
2091    for example with MatSetValues() unless one first calls MatSetUnfactored().
2092 
2093    Level: developer
2094 
2095    Concepts: matrices^LU factorization
2096 
2097 .seealso: MatLUFactorSymbolic(), MatLUFactorNumeric(), MatCholeskyFactor(),
2098           MatGetOrdering(), MatSetUnfactored(), MatFactorInfo
2099 
2100 @*/
2101 PetscErrorCode PETSCMAT_DLLEXPORT MatLUFactor(Mat mat,IS row,IS col,MatFactorInfo *info)
2102 {
2103   PetscErrorCode ierr;
2104 
2105   PetscFunctionBegin;
2106   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2107   if (row) PetscValidHeaderSpecific(row,IS_COOKIE,2);
2108   if (col) PetscValidHeaderSpecific(col,IS_COOKIE,3);
2109   PetscValidPointer(info,4);
2110   PetscValidType(mat,1);
2111   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2112   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2113   if (!mat->ops->lufactor) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2114   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2115 
2116   ierr = PetscLogEventBegin(MAT_LUFactor,mat,row,col,0);CHKERRQ(ierr);
2117   ierr = (*mat->ops->lufactor)(mat,row,col,info);CHKERRQ(ierr);
2118   ierr = PetscLogEventEnd(MAT_LUFactor,mat,row,col,0);CHKERRQ(ierr);
2119   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
2120   PetscFunctionReturn(0);
2121 }
2122 
2123 #undef __FUNCT__
2124 #define __FUNCT__ "MatILUFactor"
2125 /*@
2126    MatILUFactor - Performs in-place ILU factorization of matrix.
2127 
2128    Collective on Mat
2129 
2130    Input Parameters:
2131 +  mat - the matrix
2132 .  row - row permutation
2133 .  col - column permutation
2134 -  info - structure containing
2135 $      levels - number of levels of fill.
2136 $      expected fill - as ratio of original fill.
2137 $      1 or 0 - indicating force fill on diagonal (improves robustness for matrices
2138                 missing diagonal entries)
2139 
2140    Notes:
2141    Probably really in-place only when level of fill is zero, otherwise allocates
2142    new space to store factored matrix and deletes previous memory.
2143 
2144    Most users should employ the simplified KSP interface for linear solvers
2145    instead of working directly with matrix algebra routines such as this.
2146    See, e.g., KSPCreate().
2147 
2148    Level: developer
2149 
2150    Concepts: matrices^ILU factorization
2151 
2152 .seealso: MatILUFactorSymbolic(), MatLUFactorNumeric(), MatCholeskyFactor(), MatFactorInfo
2153 @*/
2154 PetscErrorCode PETSCMAT_DLLEXPORT MatILUFactor(Mat mat,IS row,IS col,MatFactorInfo *info)
2155 {
2156   PetscErrorCode ierr;
2157 
2158   PetscFunctionBegin;
2159   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2160   if (row) PetscValidHeaderSpecific(row,IS_COOKIE,2);
2161   if (col) PetscValidHeaderSpecific(col,IS_COOKIE,3);
2162   PetscValidPointer(info,4);
2163   PetscValidType(mat,1);
2164   if (mat->rmap.N != mat->cmap.N) SETERRQ(PETSC_ERR_ARG_WRONG,"matrix must be square");
2165   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2166   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2167   if (!mat->ops->ilufactor) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2168   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2169 
2170   ierr = PetscLogEventBegin(MAT_ILUFactor,mat,row,col,0);CHKERRQ(ierr);
2171   ierr = (*mat->ops->ilufactor)(mat,row,col,info);CHKERRQ(ierr);
2172   ierr = PetscLogEventEnd(MAT_ILUFactor,mat,row,col,0);CHKERRQ(ierr);
2173   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
2174   PetscFunctionReturn(0);
2175 }
2176 
2177 #undef __FUNCT__
2178 #define __FUNCT__ "MatLUFactorSymbolic"
2179 /*@
2180    MatLUFactorSymbolic - Performs symbolic LU factorization of matrix.
2181    Call this routine before calling MatLUFactorNumeric().
2182 
2183    Collective on Mat
2184 
2185    Input Parameters:
2186 +  mat - the matrix
2187 .  row, col - row and column permutations
2188 -  info - options for factorization, includes
2189 $          fill - expected fill as ratio of original fill.
2190 $          dtcol - pivot tolerance (0 no pivot, 1 full column pivoting)
2191 $                   Run with the option -info to determine an optimal value to use
2192 
2193    Output Parameter:
2194 .  fact - new matrix that has been symbolically factored
2195 
2196    Notes:
2197    See the users manual for additional information about
2198    choosing the fill factor for better efficiency.
2199 
2200    Most users should employ the simplified KSP interface for linear solvers
2201    instead of working directly with matrix algebra routines such as this.
2202    See, e.g., KSPCreate().
2203 
2204    Level: developer
2205 
2206    Concepts: matrices^LU symbolic factorization
2207 
2208 .seealso: MatLUFactor(), MatLUFactorNumeric(), MatCholeskyFactor(), MatFactorInfo
2209 @*/
2210 PetscErrorCode PETSCMAT_DLLEXPORT MatLUFactorSymbolic(Mat mat,IS row,IS col,MatFactorInfo *info,Mat *fact)
2211 {
2212   PetscErrorCode ierr;
2213 
2214   PetscFunctionBegin;
2215   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2216   if (row) PetscValidHeaderSpecific(row,IS_COOKIE,2);
2217   if (col) PetscValidHeaderSpecific(col,IS_COOKIE,3);
2218   PetscValidPointer(info,4);
2219   PetscValidType(mat,1);
2220   PetscValidPointer(fact,5);
2221   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2222   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2223   if (!mat->ops->lufactorsymbolic) SETERRQ1(PETSC_ERR_SUP,"Matrix type %s  symbolic LU",((PetscObject)mat)->type_name);
2224   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2225 
2226   ierr = PetscLogEventBegin(MAT_LUFactorSymbolic,mat,row,col,0);CHKERRQ(ierr);
2227   ierr = (*mat->ops->lufactorsymbolic)(mat,row,col,info,fact);CHKERRQ(ierr);
2228   ierr = PetscLogEventEnd(MAT_LUFactorSymbolic,mat,row,col,0);CHKERRQ(ierr);
2229   ierr = PetscObjectStateIncrease((PetscObject)*fact);CHKERRQ(ierr);
2230   PetscFunctionReturn(0);
2231 }
2232 
2233 #undef __FUNCT__
2234 #define __FUNCT__ "MatLUFactorNumeric"
2235 /*@
2236    MatLUFactorNumeric - Performs numeric LU factorization of a matrix.
2237    Call this routine after first calling MatLUFactorSymbolic().
2238 
2239    Collective on Mat
2240 
2241    Input Parameters:
2242 +  mat - the matrix
2243 .  info - options for factorization
2244 -  fact - the matrix generated for the factor, from MatLUFactorSymbolic()
2245 
2246    Notes:
2247    See MatLUFactor() for in-place factorization.  See
2248    MatCholeskyFactorNumeric() for the symmetric, positive definite case.
2249 
2250    Most users should employ the simplified KSP interface for linear solvers
2251    instead of working directly with matrix algebra routines such as this.
2252    See, e.g., KSPCreate().
2253 
2254    Level: developer
2255 
2256    Concepts: matrices^LU numeric factorization
2257 
2258 .seealso: MatLUFactorSymbolic(), MatLUFactor(), MatCholeskyFactor()
2259 @*/
2260 PetscErrorCode PETSCMAT_DLLEXPORT MatLUFactorNumeric(Mat mat,MatFactorInfo *info,Mat *fact)
2261 {
2262   PetscErrorCode ierr;
2263 
2264   PetscFunctionBegin;
2265   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2266   PetscValidType(mat,1);
2267   PetscValidPointer(fact,2);
2268   PetscValidHeaderSpecific(*fact,MAT_COOKIE,2);
2269   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2270   if (mat->rmap.N != (*fact)->rmap.N || mat->cmap.N != (*fact)->cmap.N) {
2271     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);
2272   }
2273   if (!(*fact)->ops->lufactornumeric) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2274   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2275   ierr = PetscLogEventBegin(MAT_LUFactorNumeric,mat,*fact,0,0);CHKERRQ(ierr);
2276   ierr = (*(*fact)->ops->lufactornumeric)(mat,info,fact);CHKERRQ(ierr);
2277   ierr = PetscLogEventEnd(MAT_LUFactorNumeric,mat,*fact,0,0);CHKERRQ(ierr);
2278 
2279   ierr = MatView_Private(*fact);CHKERRQ(ierr);
2280   ierr = PetscObjectStateIncrease((PetscObject)*fact);CHKERRQ(ierr);
2281   PetscFunctionReturn(0);
2282 }
2283 
2284 #undef __FUNCT__
2285 #define __FUNCT__ "MatCholeskyFactor"
2286 /*@
2287    MatCholeskyFactor - Performs in-place Cholesky factorization of a
2288    symmetric matrix.
2289 
2290    Collective on Mat
2291 
2292    Input Parameters:
2293 +  mat - the matrix
2294 .  perm - row and column permutations
2295 -  f - expected fill as ratio of original fill
2296 
2297    Notes:
2298    See MatLUFactor() for the nonsymmetric case.  See also
2299    MatCholeskyFactorSymbolic(), and MatCholeskyFactorNumeric().
2300 
2301    Most users should employ the simplified KSP interface for linear solvers
2302    instead of working directly with matrix algebra routines such as this.
2303    See, e.g., KSPCreate().
2304 
2305    Level: developer
2306 
2307    Concepts: matrices^Cholesky factorization
2308 
2309 .seealso: MatLUFactor(), MatCholeskyFactorSymbolic(), MatCholeskyFactorNumeric()
2310           MatGetOrdering()
2311 
2312 @*/
2313 PetscErrorCode PETSCMAT_DLLEXPORT MatCholeskyFactor(Mat mat,IS perm,MatFactorInfo *info)
2314 {
2315   PetscErrorCode ierr;
2316 
2317   PetscFunctionBegin;
2318   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2319   PetscValidType(mat,1);
2320   PetscValidHeaderSpecific(perm,IS_COOKIE,2);
2321   PetscValidPointer(info,3);
2322   if (mat->rmap.N != mat->cmap.N) SETERRQ(PETSC_ERR_ARG_WRONG,"Matrix must be square");
2323   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2324   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2325   if (!mat->ops->choleskyfactor) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2326   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2327 
2328   ierr = PetscLogEventBegin(MAT_CholeskyFactor,mat,perm,0,0);CHKERRQ(ierr);
2329   ierr = (*mat->ops->choleskyfactor)(mat,perm,info);CHKERRQ(ierr);
2330   ierr = PetscLogEventEnd(MAT_CholeskyFactor,mat,perm,0,0);CHKERRQ(ierr);
2331   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
2332   PetscFunctionReturn(0);
2333 }
2334 
2335 #undef __FUNCT__
2336 #define __FUNCT__ "MatCholeskyFactorSymbolic"
2337 /*@
2338    MatCholeskyFactorSymbolic - Performs symbolic Cholesky factorization
2339    of a symmetric matrix.
2340 
2341    Collective on Mat
2342 
2343    Input Parameters:
2344 +  mat - the matrix
2345 .  perm - row and column permutations
2346 -  info - options for factorization, includes
2347 $          fill - expected fill as ratio of original fill.
2348 $          dtcol - pivot tolerance (0 no pivot, 1 full column pivoting)
2349 $                   Run with the option -info to determine an optimal value to use
2350 
2351    Output Parameter:
2352 .  fact - the factored matrix
2353 
2354    Notes:
2355    See MatLUFactorSymbolic() for the nonsymmetric case.  See also
2356    MatCholeskyFactor() and MatCholeskyFactorNumeric().
2357 
2358    Most users should employ the simplified KSP interface for linear solvers
2359    instead of working directly with matrix algebra routines such as this.
2360    See, e.g., KSPCreate().
2361 
2362    Level: developer
2363 
2364    Concepts: matrices^Cholesky symbolic factorization
2365 
2366 .seealso: MatLUFactorSymbolic(), MatCholeskyFactor(), MatCholeskyFactorNumeric()
2367           MatGetOrdering()
2368 
2369 @*/
2370 PetscErrorCode PETSCMAT_DLLEXPORT MatCholeskyFactorSymbolic(Mat mat,IS perm,MatFactorInfo *info,Mat *fact)
2371 {
2372   PetscErrorCode ierr;
2373 
2374   PetscFunctionBegin;
2375   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2376   PetscValidType(mat,1);
2377   if (perm) PetscValidHeaderSpecific(perm,IS_COOKIE,2);
2378   PetscValidPointer(info,3);
2379   PetscValidPointer(fact,4);
2380   if (mat->rmap.N != mat->cmap.N) SETERRQ(PETSC_ERR_ARG_WRONG,"Matrix must be square");
2381   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2382   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2383   if (!mat->ops->choleskyfactorsymbolic) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2384   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2385 
2386   ierr = PetscLogEventBegin(MAT_CholeskyFactorSymbolic,mat,perm,0,0);CHKERRQ(ierr);
2387   ierr = (*mat->ops->choleskyfactorsymbolic)(mat,perm,info,fact);CHKERRQ(ierr);
2388   ierr = PetscLogEventEnd(MAT_CholeskyFactorSymbolic,mat,perm,0,0);CHKERRQ(ierr);
2389   ierr = PetscObjectStateIncrease((PetscObject)*fact);CHKERRQ(ierr);
2390   PetscFunctionReturn(0);
2391 }
2392 
2393 #undef __FUNCT__
2394 #define __FUNCT__ "MatCholeskyFactorNumeric"
2395 /*@
2396    MatCholeskyFactorNumeric - Performs numeric Cholesky factorization
2397    of a symmetric matrix. Call this routine after first calling
2398    MatCholeskyFactorSymbolic().
2399 
2400    Collective on Mat
2401 
2402    Input Parameter:
2403 .  mat - the initial matrix
2404 .  info - options for factorization
2405 -  fact - the symbolic factor of mat
2406 
2407    Output Parameter:
2408 .  fact - the factored matrix
2409 
2410    Notes:
2411    Most users should employ the simplified KSP interface for linear solvers
2412    instead of working directly with matrix algebra routines such as this.
2413    See, e.g., KSPCreate().
2414 
2415    Level: developer
2416 
2417    Concepts: matrices^Cholesky numeric factorization
2418 
2419 .seealso: MatCholeskyFactorSymbolic(), MatCholeskyFactor(), MatLUFactorNumeric()
2420 @*/
2421 PetscErrorCode PETSCMAT_DLLEXPORT MatCholeskyFactorNumeric(Mat mat,MatFactorInfo *info,Mat *fact)
2422 {
2423   PetscErrorCode ierr;
2424 
2425   PetscFunctionBegin;
2426   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2427   PetscValidType(mat,1);
2428   PetscValidPointer(fact,2);
2429   PetscValidHeaderSpecific(*fact,MAT_COOKIE,2);
2430   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2431   if (!(*fact)->ops->choleskyfactornumeric) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2432   if (mat->rmap.N != (*fact)->rmap.N || mat->cmap.N != (*fact)->cmap.N) {
2433     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);
2434   }
2435   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2436 
2437   ierr = PetscLogEventBegin(MAT_CholeskyFactorNumeric,mat,*fact,0,0);CHKERRQ(ierr);
2438   ierr = (*(*fact)->ops->choleskyfactornumeric)(mat,info,fact);CHKERRQ(ierr);
2439   ierr = PetscLogEventEnd(MAT_CholeskyFactorNumeric,mat,*fact,0,0);CHKERRQ(ierr);
2440 
2441   ierr = MatView_Private(*fact);CHKERRQ(ierr);
2442   ierr = PetscObjectStateIncrease((PetscObject)*fact);CHKERRQ(ierr);
2443   PetscFunctionReturn(0);
2444 }
2445 
2446 /* ----------------------------------------------------------------*/
2447 #undef __FUNCT__
2448 #define __FUNCT__ "MatSolve"
2449 /*@
2450    MatSolve - Solves A x = b, given a factored matrix.
2451 
2452    Collective on Mat and Vec
2453 
2454    Input Parameters:
2455 +  mat - the factored matrix
2456 -  b - the right-hand-side vector
2457 
2458    Output Parameter:
2459 .  x - the result vector
2460 
2461    Notes:
2462    The vectors b and x cannot be the same.  I.e., one cannot
2463    call MatSolve(A,x,x).
2464 
2465    Notes:
2466    Most users should employ the simplified KSP interface for linear solvers
2467    instead of working directly with matrix algebra routines such as this.
2468    See, e.g., KSPCreate().
2469 
2470    Level: developer
2471 
2472    Concepts: matrices^triangular solves
2473 
2474 .seealso: MatSolveAdd(), MatSolveTranspose(), MatSolveTransposeAdd()
2475 @*/
2476 PetscErrorCode PETSCMAT_DLLEXPORT MatSolve(Mat mat,Vec b,Vec x)
2477 {
2478   PetscErrorCode ierr;
2479 
2480   PetscFunctionBegin;
2481   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2482   PetscValidType(mat,1);
2483   PetscValidHeaderSpecific(b,VEC_COOKIE,2);
2484   PetscValidHeaderSpecific(x,VEC_COOKIE,3);
2485   PetscCheckSameComm(mat,1,b,2);
2486   PetscCheckSameComm(mat,1,x,3);
2487   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
2488   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2489   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);
2490   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);
2491   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);
2492   if (!mat->rmap.N && !mat->cmap.N) PetscFunctionReturn(0);
2493   if (!mat->ops->solve) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2494   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2495 
2496   ierr = PetscLogEventBegin(MAT_Solve,mat,b,x,0);CHKERRQ(ierr);
2497   ierr = (*mat->ops->solve)(mat,b,x);CHKERRQ(ierr);
2498   ierr = PetscLogEventEnd(MAT_Solve,mat,b,x,0);CHKERRQ(ierr);
2499   ierr = PetscObjectStateIncrease((PetscObject)x);CHKERRQ(ierr);
2500   PetscFunctionReturn(0);
2501 }
2502 
2503 #undef __FUNCT__
2504 #define __FUNCT__ "MatMatSolve_Basic"
2505 PetscErrorCode PETSCMAT_DLLEXPORT MatMatSolve_Basic(Mat A,Mat B,Mat X)
2506 {
2507   PetscErrorCode ierr;
2508   Vec            b,x;
2509   PetscInt       m,N,i;
2510   PetscScalar    *bb,*xx;
2511 
2512   PetscFunctionBegin;
2513   ierr = MatGetArray(B,&bb);CHKERRQ(ierr);
2514   ierr = MatGetArray(X,&xx);CHKERRQ(ierr);
2515   ierr = MatGetLocalSize(B,&m,PETSC_NULL);CHKERRQ(ierr);  /* number local rows */
2516   ierr = MatGetSize(B,PETSC_NULL,&N);CHKERRQ(ierr);       /* total columns in dense matrix */
2517   ierr = VecCreateMPIWithArray(A->hdr.comm,m,PETSC_DETERMINE,PETSC_NULL,&b);CHKERRQ(ierr);
2518   ierr = VecCreateMPIWithArray(A->hdr.comm,m,PETSC_DETERMINE,PETSC_NULL,&x);CHKERRQ(ierr);
2519   for (i=0; i<N; i++) {
2520     ierr = VecPlaceArray(b,bb + i*m);CHKERRQ(ierr);
2521     ierr = VecPlaceArray(x,xx + i*m);CHKERRQ(ierr);
2522     ierr = MatSolve(A,b,x);CHKERRQ(ierr);
2523   }
2524   ierr = VecDestroy(b);CHKERRQ(ierr);
2525   ierr = VecDestroy(x);CHKERRQ(ierr);
2526   ierr = MatRestoreArray(B,&bb);CHKERRQ(ierr);
2527   ierr = MatRestoreArray(X,&xx);CHKERRQ(ierr);
2528   PetscFunctionReturn(0);
2529 }
2530 
2531 #undef __FUNCT__
2532 #define __FUNCT__ "MatMatSolve"
2533 /*@
2534    MatMatSolve - Solves A X = B, given a factored matrix.
2535 
2536    Collective on Mat
2537 
2538    Input Parameters:
2539 +  mat - the factored matrix
2540 -  B - the right-hand-side matrix  (dense matrix)
2541 
2542    Output Parameter:
2543 .  B - the result matrix (dense matrix)
2544 
2545    Notes:
2546    The matrices b and x cannot be the same.  I.e., one cannot
2547    call MatMatSolve(A,x,x).
2548 
2549    Notes:
2550    Most users should usually employ the simplified KSP interface for linear solvers
2551    instead of working directly with matrix algebra routines such as this.
2552    See, e.g., KSPCreate(). However KSP can only solve for one vector (column of X)
2553    at a time.
2554 
2555    Level: developer
2556 
2557    Concepts: matrices^triangular solves
2558 
2559 .seealso: MatMatSolveAdd(), MatMatSolveTranspose(), MatMatSolveTransposeAdd(), MatLUFactor(), MatCholeskyFactor()
2560 @*/
2561 PetscErrorCode PETSCMAT_DLLEXPORT MatMatSolve(Mat A,Mat B,Mat X)
2562 {
2563   PetscErrorCode ierr;
2564 
2565   PetscFunctionBegin;
2566   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
2567   PetscValidType(A,1);
2568   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
2569   PetscValidHeaderSpecific(X,MAT_COOKIE,3);
2570   PetscCheckSameComm(A,1,B,2);
2571   PetscCheckSameComm(A,1,X,3);
2572   if (X == B) SETERRQ(PETSC_ERR_ARG_IDN,"X and B must be different matrices");
2573   if (!A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2574   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);
2575   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);
2576   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);
2577   if (!A->rmap.N && !A->cmap.N) PetscFunctionReturn(0);
2578   ierr = MatPreallocated(A);CHKERRQ(ierr);
2579 
2580   ierr = PetscLogEventBegin(MAT_MatSolve,A,B,X,0);CHKERRQ(ierr);
2581   if (!A->ops->matsolve) {
2582     ierr = PetscInfo1(A,"Mat type %s using basic MatMatSolve",((PetscObject)A)->type_name);CHKERRQ(ierr);
2583     ierr = MatMatSolve_Basic(A,B,X);CHKERRQ(ierr);
2584   } else {
2585     ierr = (*A->ops->matsolve)(A,B,X);CHKERRQ(ierr);
2586   }
2587   ierr = PetscLogEventEnd(MAT_MatSolve,A,B,X,0);CHKERRQ(ierr);
2588   ierr = PetscObjectStateIncrease((PetscObject)X);CHKERRQ(ierr);
2589   PetscFunctionReturn(0);
2590 }
2591 
2592 
2593 #undef __FUNCT__
2594 #define __FUNCT__ "MatForwardSolve"
2595 /* @
2596    MatForwardSolve - Solves L x = b, given a factored matrix, A = LU, or
2597                             U^T*D^(1/2) x = b, given a factored symmetric matrix, A = U^T*D*U,
2598 
2599    Collective on Mat and Vec
2600 
2601    Input Parameters:
2602 +  mat - the factored matrix
2603 -  b - the right-hand-side vector
2604 
2605    Output Parameter:
2606 .  x - the result vector
2607 
2608    Notes:
2609    MatSolve() should be used for most applications, as it performs
2610    a forward solve followed by a backward solve.
2611 
2612    The vectors b and x cannot be the same,  i.e., one cannot
2613    call MatForwardSolve(A,x,x).
2614 
2615    For matrix in seqsbaij format with block size larger than 1,
2616    the diagonal blocks are not implemented as D = D^(1/2) * D^(1/2) yet.
2617    MatForwardSolve() solves U^T*D y = b, and
2618    MatBackwardSolve() solves U x = y.
2619    Thus they do not provide a symmetric preconditioner.
2620 
2621    Most users should employ the simplified KSP interface for linear solvers
2622    instead of working directly with matrix algebra routines such as this.
2623    See, e.g., KSPCreate().
2624 
2625    Level: developer
2626 
2627    Concepts: matrices^forward solves
2628 
2629 .seealso: MatSolve(), MatBackwardSolve()
2630 @ */
2631 PetscErrorCode PETSCMAT_DLLEXPORT MatForwardSolve(Mat mat,Vec b,Vec x)
2632 {
2633   PetscErrorCode ierr;
2634 
2635   PetscFunctionBegin;
2636   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2637   PetscValidType(mat,1);
2638   PetscValidHeaderSpecific(b,VEC_COOKIE,2);
2639   PetscValidHeaderSpecific(x,VEC_COOKIE,3);
2640   PetscCheckSameComm(mat,1,b,2);
2641   PetscCheckSameComm(mat,1,x,3);
2642   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
2643   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2644   if (!mat->ops->forwardsolve) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2645   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);
2646   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);
2647   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);
2648   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2649   ierr = PetscLogEventBegin(MAT_ForwardSolve,mat,b,x,0);CHKERRQ(ierr);
2650   ierr = (*mat->ops->forwardsolve)(mat,b,x);CHKERRQ(ierr);
2651   ierr = PetscLogEventEnd(MAT_ForwardSolve,mat,b,x,0);CHKERRQ(ierr);
2652   ierr = PetscObjectStateIncrease((PetscObject)x);CHKERRQ(ierr);
2653   PetscFunctionReturn(0);
2654 }
2655 
2656 #undef __FUNCT__
2657 #define __FUNCT__ "MatBackwardSolve"
2658 /* @
2659    MatBackwardSolve - Solves U x = b, given a factored matrix, A = LU.
2660                              D^(1/2) U x = b, given a factored symmetric matrix, A = U^T*D*U,
2661 
2662    Collective on Mat and Vec
2663 
2664    Input Parameters:
2665 +  mat - the factored matrix
2666 -  b - the right-hand-side vector
2667 
2668    Output Parameter:
2669 .  x - the result vector
2670 
2671    Notes:
2672    MatSolve() should be used for most applications, as it performs
2673    a forward solve followed by a backward solve.
2674 
2675    The vectors b and x cannot be the same.  I.e., one cannot
2676    call MatBackwardSolve(A,x,x).
2677 
2678    For matrix in seqsbaij format with block size larger than 1,
2679    the diagonal blocks are not implemented as D = D^(1/2) * D^(1/2) yet.
2680    MatForwardSolve() solves U^T*D y = b, and
2681    MatBackwardSolve() solves U x = y.
2682    Thus they do not provide a symmetric preconditioner.
2683 
2684    Most users should employ the simplified KSP interface for linear solvers
2685    instead of working directly with matrix algebra routines such as this.
2686    See, e.g., KSPCreate().
2687 
2688    Level: developer
2689 
2690    Concepts: matrices^backward solves
2691 
2692 .seealso: MatSolve(), MatForwardSolve()
2693 @ */
2694 PetscErrorCode PETSCMAT_DLLEXPORT MatBackwardSolve(Mat mat,Vec b,Vec x)
2695 {
2696   PetscErrorCode ierr;
2697 
2698   PetscFunctionBegin;
2699   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2700   PetscValidType(mat,1);
2701   PetscValidHeaderSpecific(b,VEC_COOKIE,2);
2702   PetscValidHeaderSpecific(x,VEC_COOKIE,3);
2703   PetscCheckSameComm(mat,1,b,2);
2704   PetscCheckSameComm(mat,1,x,3);
2705   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
2706   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2707   if (!mat->ops->backwardsolve) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2708   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);
2709   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);
2710   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);
2711   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2712 
2713   ierr = PetscLogEventBegin(MAT_BackwardSolve,mat,b,x,0);CHKERRQ(ierr);
2714   ierr = (*mat->ops->backwardsolve)(mat,b,x);CHKERRQ(ierr);
2715   ierr = PetscLogEventEnd(MAT_BackwardSolve,mat,b,x,0);CHKERRQ(ierr);
2716   ierr = PetscObjectStateIncrease((PetscObject)x);CHKERRQ(ierr);
2717   PetscFunctionReturn(0);
2718 }
2719 
2720 #undef __FUNCT__
2721 #define __FUNCT__ "MatSolveAdd"
2722 /*@
2723    MatSolveAdd - Computes x = y + inv(A)*b, given a factored matrix.
2724 
2725    Collective on Mat and Vec
2726 
2727    Input Parameters:
2728 +  mat - the factored matrix
2729 .  b - the right-hand-side vector
2730 -  y - the vector to be added to
2731 
2732    Output Parameter:
2733 .  x - the result vector
2734 
2735    Notes:
2736    The vectors b and x cannot be the same.  I.e., one cannot
2737    call MatSolveAdd(A,x,y,x).
2738 
2739    Most users should employ the simplified KSP interface for linear solvers
2740    instead of working directly with matrix algebra routines such as this.
2741    See, e.g., KSPCreate().
2742 
2743    Level: developer
2744 
2745    Concepts: matrices^triangular solves
2746 
2747 .seealso: MatSolve(), MatSolveTranspose(), MatSolveTransposeAdd()
2748 @*/
2749 PetscErrorCode PETSCMAT_DLLEXPORT MatSolveAdd(Mat mat,Vec b,Vec y,Vec x)
2750 {
2751   PetscScalar    one = 1.0;
2752   Vec            tmp;
2753   PetscErrorCode ierr;
2754 
2755   PetscFunctionBegin;
2756   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2757   PetscValidType(mat,1);
2758   PetscValidHeaderSpecific(y,VEC_COOKIE,2);
2759   PetscValidHeaderSpecific(b,VEC_COOKIE,3);
2760   PetscValidHeaderSpecific(x,VEC_COOKIE,4);
2761   PetscCheckSameComm(mat,1,b,2);
2762   PetscCheckSameComm(mat,1,y,2);
2763   PetscCheckSameComm(mat,1,x,3);
2764   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
2765   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2766   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);
2767   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);
2768   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);
2769   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);
2770   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);
2771   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2772 
2773   ierr = PetscLogEventBegin(MAT_SolveAdd,mat,b,x,y);CHKERRQ(ierr);
2774   if (mat->ops->solveadd)  {
2775     ierr = (*mat->ops->solveadd)(mat,b,y,x);CHKERRQ(ierr);
2776   } else {
2777     /* do the solve then the add manually */
2778     if (x != y) {
2779       ierr = MatSolve(mat,b,x);CHKERRQ(ierr);
2780       ierr = VecAXPY(x,one,y);CHKERRQ(ierr);
2781     } else {
2782       ierr = VecDuplicate(x,&tmp);CHKERRQ(ierr);
2783       ierr = PetscLogObjectParent(mat,tmp);CHKERRQ(ierr);
2784       ierr = VecCopy(x,tmp);CHKERRQ(ierr);
2785       ierr = MatSolve(mat,b,x);CHKERRQ(ierr);
2786       ierr = VecAXPY(x,one,tmp);CHKERRQ(ierr);
2787       ierr = VecDestroy(tmp);CHKERRQ(ierr);
2788     }
2789   }
2790   ierr = PetscLogEventEnd(MAT_SolveAdd,mat,b,x,y);CHKERRQ(ierr);
2791   ierr = PetscObjectStateIncrease((PetscObject)x);CHKERRQ(ierr);
2792   PetscFunctionReturn(0);
2793 }
2794 
2795 #undef __FUNCT__
2796 #define __FUNCT__ "MatSolveTranspose"
2797 /*@
2798    MatSolveTranspose - Solves A' x = b, given a factored matrix.
2799 
2800    Collective on Mat and Vec
2801 
2802    Input Parameters:
2803 +  mat - the factored matrix
2804 -  b - the right-hand-side vector
2805 
2806    Output Parameter:
2807 .  x - the result vector
2808 
2809    Notes:
2810    The vectors b and x cannot be the same.  I.e., one cannot
2811    call MatSolveTranspose(A,x,x).
2812 
2813    Most users should employ the simplified KSP interface for linear solvers
2814    instead of working directly with matrix algebra routines such as this.
2815    See, e.g., KSPCreate().
2816 
2817    Level: developer
2818 
2819    Concepts: matrices^triangular solves
2820 
2821 .seealso: MatSolve(), MatSolveAdd(), MatSolveTransposeAdd()
2822 @*/
2823 PetscErrorCode PETSCMAT_DLLEXPORT MatSolveTranspose(Mat mat,Vec b,Vec x)
2824 {
2825   PetscErrorCode ierr;
2826 
2827   PetscFunctionBegin;
2828   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2829   PetscValidType(mat,1);
2830   PetscValidHeaderSpecific(b,VEC_COOKIE,2);
2831   PetscValidHeaderSpecific(x,VEC_COOKIE,3);
2832   PetscCheckSameComm(mat,1,b,2);
2833   PetscCheckSameComm(mat,1,x,3);
2834   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2835   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
2836   if (!mat->ops->solvetranspose) SETERRQ1(PETSC_ERR_SUP,"Matrix type %s",((PetscObject)mat)->type_name);
2837   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);
2838   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);
2839   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2840   ierr = PetscLogEventBegin(MAT_SolveTranspose,mat,b,x,0);CHKERRQ(ierr);
2841   ierr = (*mat->ops->solvetranspose)(mat,b,x);CHKERRQ(ierr);
2842   ierr = PetscLogEventEnd(MAT_SolveTranspose,mat,b,x,0);CHKERRQ(ierr);
2843   ierr = PetscObjectStateIncrease((PetscObject)x);CHKERRQ(ierr);
2844   PetscFunctionReturn(0);
2845 }
2846 
2847 #undef __FUNCT__
2848 #define __FUNCT__ "MatSolveTransposeAdd"
2849 /*@
2850    MatSolveTransposeAdd - Computes x = y + inv(Transpose(A)) b, given a
2851                       factored matrix.
2852 
2853    Collective on Mat and Vec
2854 
2855    Input Parameters:
2856 +  mat - the factored matrix
2857 .  b - the right-hand-side vector
2858 -  y - the vector to be added to
2859 
2860    Output Parameter:
2861 .  x - the result vector
2862 
2863    Notes:
2864    The vectors b and x cannot be the same.  I.e., one cannot
2865    call MatSolveTransposeAdd(A,x,y,x).
2866 
2867    Most users should employ the simplified KSP interface for linear solvers
2868    instead of working directly with matrix algebra routines such as this.
2869    See, e.g., KSPCreate().
2870 
2871    Level: developer
2872 
2873    Concepts: matrices^triangular solves
2874 
2875 .seealso: MatSolve(), MatSolveAdd(), MatSolveTranspose()
2876 @*/
2877 PetscErrorCode PETSCMAT_DLLEXPORT MatSolveTransposeAdd(Mat mat,Vec b,Vec y,Vec x)
2878 {
2879   PetscScalar    one = 1.0;
2880   PetscErrorCode ierr;
2881   Vec            tmp;
2882 
2883   PetscFunctionBegin;
2884   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2885   PetscValidType(mat,1);
2886   PetscValidHeaderSpecific(y,VEC_COOKIE,2);
2887   PetscValidHeaderSpecific(b,VEC_COOKIE,3);
2888   PetscValidHeaderSpecific(x,VEC_COOKIE,4);
2889   PetscCheckSameComm(mat,1,b,2);
2890   PetscCheckSameComm(mat,1,y,3);
2891   PetscCheckSameComm(mat,1,x,4);
2892   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
2893   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2894   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);
2895   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);
2896   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);
2897   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);
2898   ierr = MatPreallocated(mat);CHKERRQ(ierr);
2899 
2900   ierr = PetscLogEventBegin(MAT_SolveTransposeAdd,mat,b,x,y);CHKERRQ(ierr);
2901   if (mat->ops->solvetransposeadd) {
2902     ierr = (*mat->ops->solvetransposeadd)(mat,b,y,x);CHKERRQ(ierr);
2903   } else {
2904     /* do the solve then the add manually */
2905     if (x != y) {
2906       ierr = MatSolveTranspose(mat,b,x);CHKERRQ(ierr);
2907       ierr = VecAXPY(x,one,y);CHKERRQ(ierr);
2908     } else {
2909       ierr = VecDuplicate(x,&tmp);CHKERRQ(ierr);
2910       ierr = PetscLogObjectParent(mat,tmp);CHKERRQ(ierr);
2911       ierr = VecCopy(x,tmp);CHKERRQ(ierr);
2912       ierr = MatSolveTranspose(mat,b,x);CHKERRQ(ierr);
2913       ierr = VecAXPY(x,one,tmp);CHKERRQ(ierr);
2914       ierr = VecDestroy(tmp);CHKERRQ(ierr);
2915     }
2916   }
2917   ierr = PetscLogEventEnd(MAT_SolveTransposeAdd,mat,b,x,y);CHKERRQ(ierr);
2918   ierr = PetscObjectStateIncrease((PetscObject)x);CHKERRQ(ierr);
2919   PetscFunctionReturn(0);
2920 }
2921 /* ----------------------------------------------------------------*/
2922 
2923 #undef __FUNCT__
2924 #define __FUNCT__ "MatRelax"
2925 /*@
2926    MatRelax - Computes relaxation (SOR, Gauss-Seidel) sweeps.
2927 
2928    Collective on Mat and Vec
2929 
2930    Input Parameters:
2931 +  mat - the matrix
2932 .  b - the right hand side
2933 .  omega - the relaxation factor
2934 .  flag - flag indicating the type of SOR (see below)
2935 .  shift -  diagonal shift
2936 .  its - the number of iterations
2937 -  lits - the number of local iterations
2938 
2939    Output Parameters:
2940 .  x - the solution (can contain an initial guess)
2941 
2942    SOR Flags:
2943 .     SOR_FORWARD_SWEEP - forward SOR
2944 .     SOR_BACKWARD_SWEEP - backward SOR
2945 .     SOR_SYMMETRIC_SWEEP - SSOR (symmetric SOR)
2946 .     SOR_LOCAL_FORWARD_SWEEP - local forward SOR
2947 .     SOR_LOCAL_BACKWARD_SWEEP - local forward SOR
2948 .     SOR_LOCAL_SYMMETRIC_SWEEP - local SSOR
2949 .     SOR_APPLY_UPPER, SOR_APPLY_LOWER - applies
2950          upper/lower triangular part of matrix to
2951          vector (with omega)
2952 .     SOR_ZERO_INITIAL_GUESS - zero initial guess
2953 
2954    Notes:
2955    SOR_LOCAL_FORWARD_SWEEP, SOR_LOCAL_BACKWARD_SWEEP, and
2956    SOR_LOCAL_SYMMETRIC_SWEEP perform separate independent smoothings
2957    on each processor.
2958 
2959    Application programmers will not generally use MatRelax() directly,
2960    but instead will employ the KSP/PC interface.
2961 
2962    Notes for Advanced Users:
2963    The flags are implemented as bitwise inclusive or operations.
2964    For example, use (SOR_ZERO_INITIAL_GUESS | SOR_SYMMETRIC_SWEEP)
2965    to specify a zero initial guess for SSOR.
2966 
2967    Most users should employ the simplified KSP interface for linear solvers
2968    instead of working directly with matrix algebra routines such as this.
2969    See, e.g., KSPCreate().
2970 
2971    See also, MatPBRelax(). This routine will automatically call the point block
2972    version if the point version is not available.
2973 
2974    Level: developer
2975 
2976    Concepts: matrices^relaxation
2977    Concepts: matrices^SOR
2978    Concepts: matrices^Gauss-Seidel
2979 
2980 @*/
2981 PetscErrorCode PETSCMAT_DLLEXPORT MatRelax(Mat mat,Vec b,PetscReal omega,MatSORType flag,PetscReal shift,PetscInt its,PetscInt lits,Vec x)
2982 {
2983   PetscErrorCode ierr;
2984 
2985   PetscFunctionBegin;
2986   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
2987   PetscValidType(mat,1);
2988   PetscValidHeaderSpecific(b,VEC_COOKIE,2);
2989   PetscValidHeaderSpecific(x,VEC_COOKIE,8);
2990   PetscCheckSameComm(mat,1,b,2);
2991   PetscCheckSameComm(mat,1,x,8);
2992   if (!mat->ops->relax && !mat->ops->pbrelax) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2993   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2994   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2995   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);
2996   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);
2997   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);
2998   if (its <= 0) SETERRQ1(PETSC_ERR_ARG_WRONG,"Relaxation requires global its %D positive",its);
2999   if (lits <= 0) SETERRQ1(PETSC_ERR_ARG_WRONG,"Relaxation requires local its %D positive",lits);
3000 
3001   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3002   ierr = PetscLogEventBegin(MAT_Relax,mat,b,x,0);CHKERRQ(ierr);
3003   if (mat->ops->relax) {
3004     ierr =(*mat->ops->relax)(mat,b,omega,flag,shift,its,lits,x);CHKERRQ(ierr);
3005   } else {
3006     ierr =(*mat->ops->pbrelax)(mat,b,omega,flag,shift,its,lits,x);CHKERRQ(ierr);
3007   }
3008   ierr = PetscLogEventEnd(MAT_Relax,mat,b,x,0);CHKERRQ(ierr);
3009   ierr = PetscObjectStateIncrease((PetscObject)x);CHKERRQ(ierr);
3010   PetscFunctionReturn(0);
3011 }
3012 
3013 #undef __FUNCT__
3014 #define __FUNCT__ "MatPBRelax"
3015 /*@
3016    MatPBRelax - Computes relaxation (SOR, Gauss-Seidel) sweeps.
3017 
3018    Collective on Mat and Vec
3019 
3020    See MatRelax() for usage
3021 
3022    For multi-component PDEs where the Jacobian is stored in a point block format
3023    (with the PETSc BAIJ matrix formats) the relaxation is done one point block at
3024    a time. That is, the small (for example, 4 by 4) blocks along the diagonal are solved
3025    simultaneously (that is a 4 by 4 linear solve is done) to update all the values at a point.
3026 
3027    Level: developer
3028 
3029 @*/
3030 PetscErrorCode PETSCMAT_DLLEXPORT MatPBRelax(Mat mat,Vec b,PetscReal omega,MatSORType flag,PetscReal shift,PetscInt its,PetscInt lits,Vec x)
3031 {
3032   PetscErrorCode ierr;
3033 
3034   PetscFunctionBegin;
3035   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3036   PetscValidType(mat,1);
3037   PetscValidHeaderSpecific(b,VEC_COOKIE,2);
3038   PetscValidHeaderSpecific(x,VEC_COOKIE,8);
3039   PetscCheckSameComm(mat,1,b,2);
3040   PetscCheckSameComm(mat,1,x,8);
3041   if (!mat->ops->pbrelax) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3042   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3043   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3044   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);
3045   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);
3046   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);
3047   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3048 
3049   ierr = PetscLogEventBegin(MAT_Relax,mat,b,x,0);CHKERRQ(ierr);
3050   ierr =(*mat->ops->pbrelax)(mat,b,omega,flag,shift,its,lits,x);CHKERRQ(ierr);
3051   ierr = PetscLogEventEnd(MAT_Relax,mat,b,x,0);CHKERRQ(ierr);
3052   ierr = PetscObjectStateIncrease((PetscObject)x);CHKERRQ(ierr);
3053   PetscFunctionReturn(0);
3054 }
3055 
3056 #undef __FUNCT__
3057 #define __FUNCT__ "MatCopy_Basic"
3058 /*
3059       Default matrix copy routine.
3060 */
3061 PetscErrorCode MatCopy_Basic(Mat A,Mat B,MatStructure str)
3062 {
3063   PetscErrorCode    ierr;
3064   PetscInt          i,rstart,rend,nz;
3065   const PetscInt    *cwork;
3066   const PetscScalar *vwork;
3067 
3068   PetscFunctionBegin;
3069   if (B->assembled) {
3070     ierr = MatZeroEntries(B);CHKERRQ(ierr);
3071   }
3072   ierr = MatGetOwnershipRange(A,&rstart,&rend);CHKERRQ(ierr);
3073   for (i=rstart; i<rend; i++) {
3074     ierr = MatGetRow(A,i,&nz,&cwork,&vwork);CHKERRQ(ierr);
3075     ierr = MatSetValues(B,1,&i,nz,cwork,vwork,INSERT_VALUES);CHKERRQ(ierr);
3076     ierr = MatRestoreRow(A,i,&nz,&cwork,&vwork);CHKERRQ(ierr);
3077   }
3078   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3079   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3080   ierr = PetscObjectStateIncrease((PetscObject)B);CHKERRQ(ierr);
3081   PetscFunctionReturn(0);
3082 }
3083 
3084 #undef __FUNCT__
3085 #define __FUNCT__ "MatCopy"
3086 /*@
3087    MatCopy - Copys a matrix to another matrix.
3088 
3089    Collective on Mat
3090 
3091    Input Parameters:
3092 +  A - the matrix
3093 -  str - SAME_NONZERO_PATTERN or DIFFERENT_NONZERO_PATTERN
3094 
3095    Output Parameter:
3096 .  B - where the copy is put
3097 
3098    Notes:
3099    If you use SAME_NONZERO_PATTERN then the two matrices had better have the
3100    same nonzero pattern or the routine will crash.
3101 
3102    MatCopy() copies the matrix entries of a matrix to another existing
3103    matrix (after first zeroing the second matrix).  A related routine is
3104    MatConvert(), which first creates a new matrix and then copies the data.
3105 
3106    Level: intermediate
3107 
3108    Concepts: matrices^copying
3109 
3110 .seealso: MatConvert(), MatDuplicate()
3111 
3112 @*/
3113 PetscErrorCode PETSCMAT_DLLEXPORT MatCopy(Mat A,Mat B,MatStructure str)
3114 {
3115   PetscErrorCode ierr;
3116 
3117   PetscFunctionBegin;
3118   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
3119   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
3120   PetscValidType(A,1);
3121   PetscValidType(B,2);
3122   MatPreallocated(B);
3123   PetscCheckSameComm(A,1,B,2);
3124   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3125   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3126   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);
3127   ierr = MatPreallocated(A);CHKERRQ(ierr);
3128 
3129   ierr = PetscLogEventBegin(MAT_Copy,A,B,0,0);CHKERRQ(ierr);
3130   if (A->ops->copy) {
3131     ierr = (*A->ops->copy)(A,B,str);CHKERRQ(ierr);
3132   } else { /* generic conversion */
3133     ierr = MatCopy_Basic(A,B,str);CHKERRQ(ierr);
3134   }
3135   if (A->mapping) {
3136     if (B->mapping) {ierr = ISLocalToGlobalMappingDestroy(B->mapping);CHKERRQ(ierr);B->mapping = 0;}
3137     ierr = MatSetLocalToGlobalMapping(B,A->mapping);CHKERRQ(ierr);
3138   }
3139   if (A->bmapping) {
3140     if (B->bmapping) {ierr = ISLocalToGlobalMappingDestroy(B->bmapping);CHKERRQ(ierr);B->bmapping = 0;}
3141     ierr = MatSetLocalToGlobalMappingBlock(B,A->mapping);CHKERRQ(ierr);
3142   }
3143   ierr = PetscLogEventEnd(MAT_Copy,A,B,0,0);CHKERRQ(ierr);
3144   ierr = PetscObjectStateIncrease((PetscObject)B);CHKERRQ(ierr);
3145   PetscFunctionReturn(0);
3146 }
3147 
3148 #undef __FUNCT__
3149 #define __FUNCT__ "MatConvert"
3150 /*@C
3151    MatConvert - Converts a matrix to another matrix, either of the same
3152    or different type.
3153 
3154    Collective on Mat
3155 
3156    Input Parameters:
3157 +  mat - the matrix
3158 .  newtype - new matrix type.  Use MATSAME to create a new matrix of the
3159    same type as the original matrix.
3160 -  reuse - denotes if the destination matrix is to be created or reused.  Currently
3161    MAT_REUSE_MATRIX is only supported for inplace conversion, otherwise use
3162    MAT_INITIAL_MATRIX.
3163 
3164    Output Parameter:
3165 .  M - pointer to place new matrix
3166 
3167    Notes:
3168    MatConvert() first creates a new matrix and then copies the data from
3169    the first matrix.  A related routine is MatCopy(), which copies the matrix
3170    entries of one matrix to another already existing matrix context.
3171 
3172    Level: intermediate
3173 
3174    Concepts: matrices^converting between storage formats
3175 
3176 .seealso: MatCopy(), MatDuplicate()
3177 @*/
3178 PetscErrorCode PETSCMAT_DLLEXPORT MatConvert(Mat mat, MatType newtype,MatReuse reuse,Mat *M)
3179 {
3180   PetscErrorCode         ierr;
3181   PetscTruth             sametype,issame,flg;
3182   char                   convname[256],mtype[256];
3183   Mat                    B;
3184 
3185   PetscFunctionBegin;
3186   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3187   PetscValidType(mat,1);
3188   PetscValidPointer(M,3);
3189   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3190   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3191   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3192 
3193   ierr = PetscOptionsGetString(((PetscObject)mat)->prefix,"-matconvert_type",mtype,256,&flg);CHKERRQ(ierr);
3194   if (flg) {
3195     newtype = mtype;
3196   }
3197   ierr = PetscTypeCompare((PetscObject)mat,newtype,&sametype);CHKERRQ(ierr);
3198   ierr = PetscStrcmp(newtype,"same",&issame);CHKERRQ(ierr);
3199   if ((reuse == MAT_REUSE_MATRIX) && (mat != *M)) {
3200     SETERRQ(PETSC_ERR_SUP,"MAT_REUSE_MATRIX only supported for in-place conversion currently");
3201   }
3202 
3203   if ((reuse == MAT_REUSE_MATRIX) && (issame || sametype)) PetscFunctionReturn(0);
3204 
3205   if ((sametype || issame) && (reuse==MAT_INITIAL_MATRIX) && mat->ops->duplicate) {
3206     ierr = (*mat->ops->duplicate)(mat,MAT_COPY_VALUES,M);CHKERRQ(ierr);
3207   } else {
3208     PetscErrorCode (*conv)(Mat, MatType,MatReuse,Mat*)=PETSC_NULL;
3209     const char     *prefix[3] = {"seq","mpi",""};
3210     PetscInt       i;
3211     /*
3212        Order of precedence:
3213        1) See if a specialized converter is known to the current matrix.
3214        2) See if a specialized converter is known to the desired matrix class.
3215        3) See if a good general converter is registered for the desired class
3216           (as of 6/27/03 only MATMPIADJ falls into this category).
3217        4) See if a good general converter is known for the current matrix.
3218        5) Use a really basic converter.
3219     */
3220 
3221     /* 1) See if a specialized converter is known to the current matrix and the desired class */
3222     for (i=0; i<3; i++) {
3223       ierr = PetscStrcpy(convname,"MatConvert_");CHKERRQ(ierr);
3224       ierr = PetscStrcat(convname,((PetscObject)mat)->type_name);CHKERRQ(ierr);
3225       ierr = PetscStrcat(convname,"_");CHKERRQ(ierr);
3226       ierr = PetscStrcat(convname,prefix[i]);CHKERRQ(ierr);
3227       ierr = PetscStrcat(convname,newtype);CHKERRQ(ierr);
3228       ierr = PetscStrcat(convname,"_C");CHKERRQ(ierr);
3229       ierr = PetscObjectQueryFunction((PetscObject)mat,convname,(void (**)(void))&conv);CHKERRQ(ierr);
3230       if (conv) goto foundconv;
3231     }
3232 
3233     /* 2)  See if a specialized converter is known to the desired matrix class. */
3234     ierr = MatCreate(((PetscObject)mat)->comm,&B);CHKERRQ(ierr);
3235     ierr = MatSetSizes(B,mat->rmap.n,mat->cmap.n,mat->rmap.N,mat->cmap.N);CHKERRQ(ierr);
3236     ierr = MatSetType(B,newtype);CHKERRQ(ierr);
3237     for (i=0; i<3; i++) {
3238       ierr = PetscStrcpy(convname,"MatConvert_");CHKERRQ(ierr);
3239       ierr = PetscStrcat(convname,((PetscObject)mat)->type_name);CHKERRQ(ierr);
3240       ierr = PetscStrcat(convname,"_");CHKERRQ(ierr);
3241       ierr = PetscStrcat(convname,prefix[i]);CHKERRQ(ierr);
3242       ierr = PetscStrcat(convname,newtype);CHKERRQ(ierr);
3243       ierr = PetscStrcat(convname,"_C");CHKERRQ(ierr);
3244       ierr = PetscObjectQueryFunction((PetscObject)B,convname,(void (**)(void))&conv);CHKERRQ(ierr);
3245       if (conv) {
3246         ierr = MatDestroy(B);CHKERRQ(ierr);
3247         goto foundconv;
3248       }
3249     }
3250 
3251     /* 3) See if a good general converter is registered for the desired class */
3252     conv = B->ops->convertfrom;
3253     ierr = MatDestroy(B);CHKERRQ(ierr);
3254     if (conv) goto foundconv;
3255 
3256     /* 4) See if a good general converter is known for the current matrix */
3257     if (mat->ops->convert) {
3258       conv = mat->ops->convert;
3259     }
3260     if (conv) goto foundconv;
3261 
3262     /* 5) Use a really basic converter. */
3263     conv = MatConvert_Basic;
3264 
3265     foundconv:
3266     ierr = PetscLogEventBegin(MAT_Convert,mat,0,0,0);CHKERRQ(ierr);
3267     ierr = (*conv)(mat,newtype,reuse,M);CHKERRQ(ierr);
3268     ierr = PetscLogEventEnd(MAT_Convert,mat,0,0,0);CHKERRQ(ierr);
3269   }
3270   ierr = PetscObjectStateIncrease((PetscObject)*M);CHKERRQ(ierr);
3271   PetscFunctionReturn(0);
3272 }
3273 
3274 
3275 #undef __FUNCT__
3276 #define __FUNCT__ "MatDuplicate"
3277 /*@
3278    MatDuplicate - Duplicates a matrix including the non-zero structure.
3279 
3280    Collective on Mat
3281 
3282    Input Parameters:
3283 +  mat - the matrix
3284 -  op - either MAT_DO_NOT_COPY_VALUES or MAT_COPY_VALUES, cause it to copy nonzero
3285         values as well or not
3286 
3287    Output Parameter:
3288 .  M - pointer to place new matrix
3289 
3290    Level: intermediate
3291 
3292    Concepts: matrices^duplicating
3293 
3294 .seealso: MatCopy(), MatConvert()
3295 @*/
3296 PetscErrorCode PETSCMAT_DLLEXPORT MatDuplicate(Mat mat,MatDuplicateOption op,Mat *M)
3297 {
3298   PetscErrorCode ierr;
3299   Mat            B;
3300 
3301   PetscFunctionBegin;
3302   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3303   PetscValidType(mat,1);
3304   PetscValidPointer(M,3);
3305   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3306   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3307   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3308 
3309   *M  = 0;
3310   if (!mat->ops->duplicate) {
3311     SETERRQ(PETSC_ERR_SUP,"Not written for this matrix type");
3312   }
3313   ierr = PetscLogEventBegin(MAT_Convert,mat,0,0,0);CHKERRQ(ierr);
3314   ierr = (*mat->ops->duplicate)(mat,op,M);CHKERRQ(ierr);
3315   B = *M;
3316   if (mat->mapping) {
3317     ierr = MatSetLocalToGlobalMapping(B,mat->mapping);CHKERRQ(ierr);
3318   }
3319   if (mat->bmapping) {
3320     ierr = MatSetLocalToGlobalMappingBlock(B,mat->bmapping);CHKERRQ(ierr);
3321   }
3322   ierr = PetscMapCopy(((PetscObject)mat)->comm,&mat->rmap,&B->rmap);CHKERRQ(ierr);
3323   ierr = PetscMapCopy(((PetscObject)mat)->comm,&mat->cmap,&B->cmap);CHKERRQ(ierr);
3324 
3325   ierr = PetscLogEventEnd(MAT_Convert,mat,0,0,0);CHKERRQ(ierr);
3326   ierr = PetscObjectStateIncrease((PetscObject)B);CHKERRQ(ierr);
3327   PetscFunctionReturn(0);
3328 }
3329 
3330 #undef __FUNCT__
3331 #define __FUNCT__ "MatGetDiagonal"
3332 /*@
3333    MatGetDiagonal - Gets the diagonal of a matrix.
3334 
3335    Collective on Mat and Vec
3336 
3337    Input Parameters:
3338 +  mat - the matrix
3339 -  v - the vector for storing the diagonal
3340 
3341    Output Parameter:
3342 .  v - the diagonal of the matrix
3343 
3344    Notes: The result of this call are the same as if one converted the matrix to dense format
3345       and found the minimum value in each row (i.e. the implicit zeros are counted as zeros).
3346 
3347    Level: intermediate
3348 
3349    Concepts: matrices^accessing diagonals
3350 
3351 .seealso: MatGetRow(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMaxAbs()
3352 @*/
3353 PetscErrorCode PETSCMAT_DLLEXPORT MatGetDiagonal(Mat mat,Vec v)
3354 {
3355   PetscErrorCode ierr;
3356 
3357   PetscFunctionBegin;
3358   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3359   PetscValidType(mat,1);
3360   PetscValidHeaderSpecific(v,VEC_COOKIE,2);
3361   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3362   if (!mat->ops->getdiagonal) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3363   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3364 
3365   ierr = (*mat->ops->getdiagonal)(mat,v);CHKERRQ(ierr);
3366   ierr = PetscObjectStateIncrease((PetscObject)v);CHKERRQ(ierr);
3367   PetscFunctionReturn(0);
3368 }
3369 
3370 #undef __FUNCT__
3371 #define __FUNCT__ "MatGetRowMin"
3372 /*@
3373    MatGetRowMin - Gets the minimum value (of the real part) of each
3374         row of the matrix
3375 
3376    Collective on Mat and Vec
3377 
3378    Input Parameters:
3379 .  mat - the matrix
3380 
3381    Output Parameter:
3382 +  v - the vector for storing the maximums
3383 -  idx - the indices of the column found for each row (optional)
3384 
3385    Level: intermediate
3386 
3387    Notes: The result of this call are the same as if one converted the matrix to dense format
3388       and found the minimum value in each row (i.e. the implicit zeros are counted as zeros).
3389 
3390     This code is only implemented for a couple of matrix formats.
3391 
3392    Concepts: matrices^getting row maximums
3393 
3394 .seealso: MatGetDiagonal(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMaxAbs(),
3395           MatGetRowMax()
3396 @*/
3397 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRowMin(Mat mat,Vec v,PetscInt idx[])
3398 {
3399   PetscErrorCode ierr;
3400 
3401   PetscFunctionBegin;
3402   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3403   PetscValidType(mat,1);
3404   PetscValidHeaderSpecific(v,VEC_COOKIE,2);
3405   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3406   if (!mat->ops->getrowmax) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3407   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3408 
3409   ierr = (*mat->ops->getrowmin)(mat,v,idx);CHKERRQ(ierr);
3410   ierr = PetscObjectStateIncrease((PetscObject)v);CHKERRQ(ierr);
3411   PetscFunctionReturn(0);
3412 }
3413 
3414 #undef __FUNCT__
3415 #define __FUNCT__ "MatGetRowMax"
3416 /*@
3417    MatGetRowMax - Gets the maximum value (of the real part) of each
3418         row of the matrix
3419 
3420    Collective on Mat and Vec
3421 
3422    Input Parameters:
3423 .  mat - the matrix
3424 
3425    Output Parameter:
3426 +  v - the vector for storing the maximums
3427 -  idx - the indices of the column found for each row (optional)
3428 
3429    Level: intermediate
3430 
3431    Notes: The result of this call are the same as if one converted the matrix to dense format
3432       and found the minimum value in each row (i.e. the implicit zeros are counted as zeros).
3433 
3434     This code is only implemented for a couple of matrix formats.
3435 
3436    Concepts: matrices^getting row maximums
3437 
3438 .seealso: MatGetDiagonal(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMaxAbs(), MatGetRowMin()
3439 @*/
3440 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRowMax(Mat mat,Vec v,PetscInt idx[])
3441 {
3442   PetscErrorCode ierr;
3443 
3444   PetscFunctionBegin;
3445   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3446   PetscValidType(mat,1);
3447   PetscValidHeaderSpecific(v,VEC_COOKIE,2);
3448   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3449   if (!mat->ops->getrowmax) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3450   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3451 
3452   ierr = (*mat->ops->getrowmax)(mat,v,idx);CHKERRQ(ierr);
3453   ierr = PetscObjectStateIncrease((PetscObject)v);CHKERRQ(ierr);
3454   PetscFunctionReturn(0);
3455 }
3456 
3457 #undef __FUNCT__
3458 #define __FUNCT__ "MatGetRowMaxAbs"
3459 /*@
3460    MatGetRowMaxAbs - Gets the maximum value (in absolute value) of each
3461         row of the matrix
3462 
3463    Collective on Mat and Vec
3464 
3465    Input Parameters:
3466 .  mat - the matrix
3467 
3468    Output Parameter:
3469 +  v - the vector for storing the maximums
3470 -  idx - the indices of the column found for each row (optional)
3471 
3472    Level: intermediate
3473 
3474    Notes: if a row is completely empty or has only 0.0 values then the idx[] value for that
3475     row is 0 (the first column).
3476 
3477     This code is only implemented for a couple of matrix formats.
3478 
3479    Concepts: matrices^getting row maximums
3480 
3481 .seealso: MatGetDiagonal(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMax(), MatGetRowMin()
3482 @*/
3483 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRowMaxAbs(Mat mat,Vec v,PetscInt idx[])
3484 {
3485   PetscErrorCode ierr;
3486 
3487   PetscFunctionBegin;
3488   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3489   PetscValidType(mat,1);
3490   PetscValidHeaderSpecific(v,VEC_COOKIE,2);
3491   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3492   if (!mat->ops->getrowmaxabs) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3493   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3494 
3495   ierr = (*mat->ops->getrowmaxabs)(mat,v,idx);CHKERRQ(ierr);
3496   ierr = PetscObjectStateIncrease((PetscObject)v);CHKERRQ(ierr);
3497   PetscFunctionReturn(0);
3498 }
3499 
3500 #undef __FUNCT__
3501 #define __FUNCT__ "MatGetRowSum"
3502 /*@
3503    MatGetRowSum - Gets the sum of each row of the matrix
3504 
3505    Collective on Mat and Vec
3506 
3507    Input Parameters:
3508 .  mat - the matrix
3509 
3510    Output Parameter:
3511 .  v - the vector for storing the maximums
3512 
3513    Level: intermediate
3514 
3515    Notes: This code is slow since it is not currently specialized for different formats
3516 
3517    Concepts: matrices^getting row sums
3518 
3519 .seealso: MatGetDiagonal(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMax(), MatGetRowMin()
3520 @*/
3521 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRowSum(Mat mat, Vec v)
3522 {
3523   PetscInt       start, end, row;
3524   PetscScalar   *array;
3525   PetscErrorCode ierr;
3526 
3527   PetscFunctionBegin;
3528   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3529   PetscValidType(mat,1);
3530   PetscValidHeaderSpecific(v,VEC_COOKIE,2);
3531   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3532   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3533   ierr = MatGetOwnershipRange(mat, &start, &end);CHKERRQ(ierr);
3534   ierr = VecGetArray(v, &array);CHKERRQ(ierr);
3535   for(row = start; row < end; ++row) {
3536     PetscInt           ncols, col;
3537     const PetscInt    *cols;
3538     const PetscScalar *vals;
3539 
3540     array[row - start] = 0.0;
3541     ierr = MatGetRow(mat, row, &ncols, &cols, &vals);CHKERRQ(ierr);
3542     for(col = 0; col < ncols; col++) {
3543       array[row - start] += vals[col];
3544     }
3545     ierr = MatRestoreRow(mat, row, &ncols, &cols, &vals);CHKERRQ(ierr);
3546   }
3547   ierr = VecRestoreArray(v, &array);CHKERRQ(ierr);
3548   ierr = PetscObjectStateIncrease((PetscObject) v);CHKERRQ(ierr);
3549   PetscFunctionReturn(0);
3550 }
3551 
3552 #undef __FUNCT__
3553 #define __FUNCT__ "MatTranspose"
3554 /*@
3555    MatTranspose - Computes an in-place or out-of-place transpose of a matrix.
3556 
3557    Collective on Mat
3558 
3559    Input Parameter:
3560 +  mat - the matrix to transpose
3561 -  reuse - store the transpose matrix in the provided B
3562 
3563    Output Parameters:
3564 .  B - the transpose
3565 
3566    Notes:
3567      If you  pass in &mat for B the matrix will be done in place
3568 
3569    Level: intermediate
3570 
3571    Concepts: matrices^transposing
3572 
3573 .seealso: MatMultTranspose(), MatMultTransposeAdd(), MatIsTranspose()
3574 @*/
3575 PetscErrorCode PETSCMAT_DLLEXPORT MatTranspose(Mat mat,MatReuse reuse,Mat *B)
3576 {
3577   PetscErrorCode ierr;
3578 
3579   PetscFunctionBegin;
3580   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3581   PetscValidType(mat,1);
3582   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3583   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3584   if (*B == mat && reuse == MAT_INITIAL_MATRIX) SETERRQ(PETSC_ERR_ARG_WRONG,"Must use MAT_REUSE_MATRIX if mat == *B");
3585   if (!mat->ops->transpose) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3586   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3587 
3588   ierr = PetscLogEventBegin(MAT_Transpose,mat,0,0,0);CHKERRQ(ierr);
3589   ierr = (*mat->ops->transpose)(mat,reuse,B);CHKERRQ(ierr);
3590   ierr = PetscLogEventEnd(MAT_Transpose,mat,0,0,0);CHKERRQ(ierr);
3591   if (B) {ierr = PetscObjectStateIncrease((PetscObject)*B);CHKERRQ(ierr);}
3592   PetscFunctionReturn(0);
3593 }
3594 
3595 #undef __FUNCT__
3596 #define __FUNCT__ "MatIsTranspose"
3597 /*@
3598    MatIsTranspose - Test whether a matrix is another one's transpose,
3599         or its own, in which case it tests symmetry.
3600 
3601    Collective on Mat
3602 
3603    Input Parameter:
3604 +  A - the matrix to test
3605 -  B - the matrix to test against, this can equal the first parameter
3606 
3607    Output Parameters:
3608 .  flg - the result
3609 
3610    Notes:
3611    Only available for SeqAIJ/MPIAIJ matrices. The sequential algorithm
3612    has a running time of the order of the number of nonzeros; the parallel
3613    test involves parallel copies of the block-offdiagonal parts of the matrix.
3614 
3615    Level: intermediate
3616 
3617    Concepts: matrices^transposing, matrix^symmetry
3618 
3619 .seealso: MatTranspose(), MatIsSymmetric(), MatIsHermitian()
3620 @*/
3621 PetscErrorCode PETSCMAT_DLLEXPORT MatIsTranspose(Mat A,Mat B,PetscReal tol,PetscTruth *flg)
3622 {
3623   PetscErrorCode ierr,(*f)(Mat,Mat,PetscReal,PetscTruth*),(*g)(Mat,Mat,PetscReal,PetscTruth*);
3624 
3625   PetscFunctionBegin;
3626   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
3627   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
3628   PetscValidPointer(flg,3);
3629   ierr = PetscObjectQueryFunction((PetscObject)A,"MatIsTranspose_C",(void (**)(void))&f);CHKERRQ(ierr);
3630   ierr = PetscObjectQueryFunction((PetscObject)B,"MatIsTranspose_C",(void (**)(void))&g);CHKERRQ(ierr);
3631   if (f && g) {
3632     if (f==g) {
3633       ierr = (*f)(A,B,tol,flg);CHKERRQ(ierr);
3634     } else {
3635       SETERRQ(PETSC_ERR_ARG_NOTSAMETYPE,"Matrices do not have the same comparator for symmetry test");
3636     }
3637   }
3638   PetscFunctionReturn(0);
3639 }
3640 
3641 #undef __FUNCT__
3642 #define __FUNCT__ "MatIsHermitianTranspose"
3643 /*@
3644    MatIsHermitianTranspose - Test whether a matrix is another one's Hermitian transpose,
3645 
3646    Collective on Mat
3647 
3648    Input Parameter:
3649 +  A - the matrix to test
3650 -  B - the matrix to test against, this can equal the first parameter
3651 
3652    Output Parameters:
3653 .  flg - the result
3654 
3655    Notes:
3656    Only available for SeqAIJ/MPIAIJ matrices. The sequential algorithm
3657    has a running time of the order of the number of nonzeros; the parallel
3658    test involves parallel copies of the block-offdiagonal parts of the matrix.
3659 
3660    Level: intermediate
3661 
3662    Concepts: matrices^transposing, matrix^symmetry
3663 
3664 .seealso: MatTranspose(), MatIsSymmetric(), MatIsHermitian(), MatIsTranspose()
3665 @*/
3666 PetscErrorCode PETSCMAT_DLLEXPORT MatIsHermitianTranspose(Mat A,Mat B,PetscReal tol,PetscTruth *flg)
3667 {
3668   PetscErrorCode ierr,(*f)(Mat,Mat,PetscReal,PetscTruth*),(*g)(Mat,Mat,PetscReal,PetscTruth*);
3669 
3670   PetscFunctionBegin;
3671   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
3672   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
3673   PetscValidPointer(flg,3);
3674   ierr = PetscObjectQueryFunction((PetscObject)A,"MatIsHermitianTranspose_C",(void (**)(void))&f);CHKERRQ(ierr);
3675   ierr = PetscObjectQueryFunction((PetscObject)B,"MatIsHermitianTranspose_C",(void (**)(void))&g);CHKERRQ(ierr);
3676   if (f && g) {
3677     if (f==g) {
3678       ierr = (*f)(A,B,tol,flg);CHKERRQ(ierr);
3679     } else {
3680       SETERRQ(PETSC_ERR_ARG_NOTSAMETYPE,"Matrices do not have the same comparator for Hermitian test");
3681     }
3682   }
3683   PetscFunctionReturn(0);
3684 }
3685 
3686 #undef __FUNCT__
3687 #define __FUNCT__ "MatPermute"
3688 /*@
3689    MatPermute - Creates a new matrix with rows and columns permuted from the
3690    original.
3691 
3692    Collective on Mat
3693 
3694    Input Parameters:
3695 +  mat - the matrix to permute
3696 .  row - row permutation, each processor supplies only the permutation for its rows
3697 -  col - column permutation, each processor needs the entire column permutation, that is
3698          this is the same size as the total number of columns in the matrix
3699 
3700    Output Parameters:
3701 .  B - the permuted matrix
3702 
3703    Level: advanced
3704 
3705    Concepts: matrices^permuting
3706 
3707 .seealso: MatGetOrdering()
3708 @*/
3709 PetscErrorCode PETSCMAT_DLLEXPORT MatPermute(Mat mat,IS row,IS col,Mat *B)
3710 {
3711   PetscErrorCode ierr;
3712 
3713   PetscFunctionBegin;
3714   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3715   PetscValidType(mat,1);
3716   PetscValidHeaderSpecific(row,IS_COOKIE,2);
3717   PetscValidHeaderSpecific(col,IS_COOKIE,3);
3718   PetscValidPointer(B,4);
3719   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3720   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3721   if (!mat->ops->permute) SETERRQ1(PETSC_ERR_SUP,"MatPermute not available for Mat type %s",((PetscObject)mat)->type_name);
3722   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3723 
3724   ierr = (*mat->ops->permute)(mat,row,col,B);CHKERRQ(ierr);
3725   ierr = PetscObjectStateIncrease((PetscObject)*B);CHKERRQ(ierr);
3726   PetscFunctionReturn(0);
3727 }
3728 
3729 #undef __FUNCT__
3730 #define __FUNCT__ "MatPermuteSparsify"
3731 /*@
3732   MatPermuteSparsify - Creates a new matrix with rows and columns permuted from the
3733   original and sparsified to the prescribed tolerance.
3734 
3735   Collective on Mat
3736 
3737   Input Parameters:
3738 + A    - The matrix to permute
3739 . band - The half-bandwidth of the sparsified matrix, or PETSC_DECIDE
3740 . frac - The half-bandwidth as a fraction of the total size, or 0.0
3741 . tol  - The drop tolerance
3742 . rowp - The row permutation
3743 - colp - The column permutation
3744 
3745   Output Parameter:
3746 . B    - The permuted, sparsified matrix
3747 
3748   Level: advanced
3749 
3750   Note:
3751   The default behavior (band = PETSC_DECIDE and frac = 0.0) is to
3752   restrict the half-bandwidth of the resulting matrix to 5% of the
3753   total matrix size.
3754 
3755 .keywords: matrix, permute, sparsify
3756 
3757 .seealso: MatGetOrdering(), MatPermute()
3758 @*/
3759 PetscErrorCode PETSCMAT_DLLEXPORT MatPermuteSparsify(Mat A, PetscInt band, PetscReal frac, PetscReal tol, IS rowp, IS colp, Mat *B)
3760 {
3761   IS                irowp, icolp;
3762   PetscInt          *rows, *cols;
3763   PetscInt          M, N, locRowStart, locRowEnd;
3764   PetscInt          nz, newNz;
3765   const PetscInt    *cwork;
3766   PetscInt          *cnew;
3767   const PetscScalar *vwork;
3768   PetscScalar       *vnew;
3769   PetscInt          bw, issize;
3770   PetscInt          row, locRow, newRow, col, newCol;
3771   PetscErrorCode    ierr;
3772 
3773   PetscFunctionBegin;
3774   PetscValidHeaderSpecific(A,    MAT_COOKIE,1);
3775   PetscValidHeaderSpecific(rowp, IS_COOKIE,5);
3776   PetscValidHeaderSpecific(colp, IS_COOKIE,6);
3777   PetscValidPointer(B,7);
3778   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE, "Not for unassembled matrix");
3779   if (A->factor)     SETERRQ(PETSC_ERR_ARG_WRONGSTATE, "Not for factored matrix");
3780   if (!A->ops->permutesparsify) {
3781     ierr = MatGetSize(A, &M, &N);CHKERRQ(ierr);
3782     ierr = MatGetOwnershipRange(A, &locRowStart, &locRowEnd);CHKERRQ(ierr);
3783     ierr = ISGetSize(rowp, &issize);CHKERRQ(ierr);
3784     if (issize != M) SETERRQ2(PETSC_ERR_ARG_WRONG, "Wrong size %D for row permutation, should be %D", issize, M);
3785     ierr = ISGetSize(colp, &issize);CHKERRQ(ierr);
3786     if (issize != N) SETERRQ2(PETSC_ERR_ARG_WRONG, "Wrong size %D for column permutation, should be %D", issize, N);
3787     ierr = ISInvertPermutation(rowp, 0, &irowp);CHKERRQ(ierr);
3788     ierr = ISGetIndices(irowp, &rows);CHKERRQ(ierr);
3789     ierr = ISInvertPermutation(colp, 0, &icolp);CHKERRQ(ierr);
3790     ierr = ISGetIndices(icolp, &cols);CHKERRQ(ierr);
3791     ierr = PetscMalloc(N * sizeof(PetscInt),         &cnew);CHKERRQ(ierr);
3792     ierr = PetscMalloc(N * sizeof(PetscScalar), &vnew);CHKERRQ(ierr);
3793 
3794     /* Setup bandwidth to include */
3795     if (band == PETSC_DECIDE) {
3796       if (frac <= 0.0)
3797         bw = (PetscInt) (M * 0.05);
3798       else
3799         bw = (PetscInt) (M * frac);
3800     } else {
3801       if (band <= 0) SETERRQ(PETSC_ERR_ARG_WRONG, "Bandwidth must be a positive integer");
3802       bw = band;
3803     }
3804 
3805     /* Put values into new matrix */
3806     ierr = MatDuplicate(A, MAT_DO_NOT_COPY_VALUES, B);CHKERRQ(ierr);
3807     for(row = locRowStart, locRow = 0; row < locRowEnd; row++, locRow++) {
3808       ierr = MatGetRow(A, row, &nz, &cwork, &vwork);CHKERRQ(ierr);
3809       newRow   = rows[locRow]+locRowStart;
3810       for(col = 0, newNz = 0; col < nz; col++) {
3811         newCol = cols[cwork[col]];
3812         if ((newCol >= newRow - bw) && (newCol < newRow + bw) && (PetscAbsScalar(vwork[col]) >= tol)) {
3813           cnew[newNz] = newCol;
3814           vnew[newNz] = vwork[col];
3815           newNz++;
3816         }
3817       }
3818       ierr = MatSetValues(*B, 1, &newRow, newNz, cnew, vnew, INSERT_VALUES);CHKERRQ(ierr);
3819       ierr = MatRestoreRow(A, row, &nz, &cwork, &vwork);CHKERRQ(ierr);
3820     }
3821     ierr = PetscFree(cnew);CHKERRQ(ierr);
3822     ierr = PetscFree(vnew);CHKERRQ(ierr);
3823     ierr = MatAssemblyBegin(*B, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3824     ierr = MatAssemblyEnd(*B, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3825     ierr = ISRestoreIndices(irowp, &rows);CHKERRQ(ierr);
3826     ierr = ISRestoreIndices(icolp, &cols);CHKERRQ(ierr);
3827     ierr = ISDestroy(irowp);CHKERRQ(ierr);
3828     ierr = ISDestroy(icolp);CHKERRQ(ierr);
3829   } else {
3830     ierr = (*A->ops->permutesparsify)(A, band, frac, tol, rowp, colp, B);CHKERRQ(ierr);
3831   }
3832   ierr = PetscObjectStateIncrease((PetscObject)*B);CHKERRQ(ierr);
3833   PetscFunctionReturn(0);
3834 }
3835 
3836 #undef __FUNCT__
3837 #define __FUNCT__ "MatEqual"
3838 /*@
3839    MatEqual - Compares two matrices.
3840 
3841    Collective on Mat
3842 
3843    Input Parameters:
3844 +  A - the first matrix
3845 -  B - the second matrix
3846 
3847    Output Parameter:
3848 .  flg - PETSC_TRUE if the matrices are equal; PETSC_FALSE otherwise.
3849 
3850    Level: intermediate
3851 
3852    Concepts: matrices^equality between
3853 @*/
3854 PetscErrorCode PETSCMAT_DLLEXPORT MatEqual(Mat A,Mat B,PetscTruth *flg)
3855 {
3856   PetscErrorCode ierr;
3857 
3858   PetscFunctionBegin;
3859   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
3860   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
3861   PetscValidType(A,1);
3862   PetscValidType(B,2);
3863   MatPreallocated(B);
3864   PetscValidIntPointer(flg,3);
3865   PetscCheckSameComm(A,1,B,2);
3866   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3867   if (!B->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3868   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);
3869   if (!A->ops->equal) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)A)->type_name);
3870   if (!B->ops->equal) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)B)->type_name);
3871   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);
3872   ierr = MatPreallocated(A);CHKERRQ(ierr);
3873 
3874   ierr = (*A->ops->equal)(A,B,flg);CHKERRQ(ierr);
3875   PetscFunctionReturn(0);
3876 }
3877 
3878 #undef __FUNCT__
3879 #define __FUNCT__ "MatDiagonalScale"
3880 /*@
3881    MatDiagonalScale - Scales a matrix on the left and right by diagonal
3882    matrices that are stored as vectors.  Either of the two scaling
3883    matrices can be PETSC_NULL.
3884 
3885    Collective on Mat
3886 
3887    Input Parameters:
3888 +  mat - the matrix to be scaled
3889 .  l - the left scaling vector (or PETSC_NULL)
3890 -  r - the right scaling vector (or PETSC_NULL)
3891 
3892    Notes:
3893    MatDiagonalScale() computes A = LAR, where
3894    L = a diagonal matrix (stored as a vector), R = a diagonal matrix (stored as a vector)
3895 
3896    Level: intermediate
3897 
3898    Concepts: matrices^diagonal scaling
3899    Concepts: diagonal scaling of matrices
3900 
3901 .seealso: MatScale()
3902 @*/
3903 PetscErrorCode PETSCMAT_DLLEXPORT MatDiagonalScale(Mat mat,Vec l,Vec r)
3904 {
3905   PetscErrorCode ierr;
3906 
3907   PetscFunctionBegin;
3908   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3909   PetscValidType(mat,1);
3910   if (!mat->ops->diagonalscale) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3911   if (l) {PetscValidHeaderSpecific(l,VEC_COOKIE,2);PetscCheckSameComm(mat,1,l,2);}
3912   if (r) {PetscValidHeaderSpecific(r,VEC_COOKIE,3);PetscCheckSameComm(mat,1,r,3);}
3913   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3914   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3915   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3916 
3917   ierr = PetscLogEventBegin(MAT_Scale,mat,0,0,0);CHKERRQ(ierr);
3918   ierr = (*mat->ops->diagonalscale)(mat,l,r);CHKERRQ(ierr);
3919   ierr = PetscLogEventEnd(MAT_Scale,mat,0,0,0);CHKERRQ(ierr);
3920   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
3921   PetscFunctionReturn(0);
3922 }
3923 
3924 #undef __FUNCT__
3925 #define __FUNCT__ "MatScale"
3926 /*@
3927     MatScale - Scales all elements of a matrix by a given number.
3928 
3929     Collective on Mat
3930 
3931     Input Parameters:
3932 +   mat - the matrix to be scaled
3933 -   a  - the scaling value
3934 
3935     Output Parameter:
3936 .   mat - the scaled matrix
3937 
3938     Level: intermediate
3939 
3940     Concepts: matrices^scaling all entries
3941 
3942 .seealso: MatDiagonalScale()
3943 @*/
3944 PetscErrorCode PETSCMAT_DLLEXPORT MatScale(Mat mat,PetscScalar a)
3945 {
3946   PetscErrorCode ierr;
3947 
3948   PetscFunctionBegin;
3949   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3950   PetscValidType(mat,1);
3951   if (!mat->ops->scale) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3952   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3953   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3954   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3955 
3956   ierr = PetscLogEventBegin(MAT_Scale,mat,0,0,0);CHKERRQ(ierr);
3957   ierr = (*mat->ops->scale)(mat,a);CHKERRQ(ierr);
3958   ierr = PetscLogEventEnd(MAT_Scale,mat,0,0,0);CHKERRQ(ierr);
3959   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
3960   PetscFunctionReturn(0);
3961 }
3962 
3963 #undef __FUNCT__
3964 #define __FUNCT__ "MatNorm"
3965 /*@
3966    MatNorm - Calculates various norms of a matrix.
3967 
3968    Collective on Mat
3969 
3970    Input Parameters:
3971 +  mat - the matrix
3972 -  type - the type of norm, NORM_1, NORM_FROBENIUS, NORM_INFINITY
3973 
3974    Output Parameters:
3975 .  nrm - the resulting norm
3976 
3977    Level: intermediate
3978 
3979    Concepts: matrices^norm
3980    Concepts: norm^of matrix
3981 @*/
3982 PetscErrorCode PETSCMAT_DLLEXPORT MatNorm(Mat mat,NormType type,PetscReal *nrm)
3983 {
3984   PetscErrorCode ierr;
3985 
3986   PetscFunctionBegin;
3987   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
3988   PetscValidType(mat,1);
3989   PetscValidScalarPointer(nrm,3);
3990 
3991   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3992   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3993   if (!mat->ops->norm) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3994   ierr = MatPreallocated(mat);CHKERRQ(ierr);
3995 
3996   ierr = (*mat->ops->norm)(mat,type,nrm);CHKERRQ(ierr);
3997   PetscFunctionReturn(0);
3998 }
3999 
4000 /*
4001      This variable is used to prevent counting of MatAssemblyBegin() that
4002    are called from within a MatAssemblyEnd().
4003 */
4004 static PetscInt MatAssemblyEnd_InUse = 0;
4005 #undef __FUNCT__
4006 #define __FUNCT__ "MatAssemblyBegin"
4007 /*@
4008    MatAssemblyBegin - Begins assembling the matrix.  This routine should
4009    be called after completing all calls to MatSetValues().
4010 
4011    Collective on Mat
4012 
4013    Input Parameters:
4014 +  mat - the matrix
4015 -  type - type of assembly, either MAT_FLUSH_ASSEMBLY or MAT_FINAL_ASSEMBLY
4016 
4017    Notes:
4018    MatSetValues() generally caches the values.  The matrix is ready to
4019    use only after MatAssemblyBegin() and MatAssemblyEnd() have been called.
4020    Use MAT_FLUSH_ASSEMBLY when switching between ADD_VALUES and INSERT_VALUES
4021    in MatSetValues(); use MAT_FINAL_ASSEMBLY for the final assembly before
4022    using the matrix.
4023 
4024    Level: beginner
4025 
4026    Concepts: matrices^assembling
4027 
4028 .seealso: MatAssemblyEnd(), MatSetValues(), MatAssembled()
4029 @*/
4030 PetscErrorCode PETSCMAT_DLLEXPORT MatAssemblyBegin(Mat mat,MatAssemblyType type)
4031 {
4032   PetscErrorCode ierr;
4033 
4034   PetscFunctionBegin;
4035   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4036   PetscValidType(mat,1);
4037   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4038   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix.\nDid you forget to call MatSetUnfactored()?");
4039   if (mat->assembled) {
4040     mat->was_assembled = PETSC_TRUE;
4041     mat->assembled     = PETSC_FALSE;
4042   }
4043   if (!MatAssemblyEnd_InUse) {
4044     ierr = PetscLogEventBegin(MAT_AssemblyBegin,mat,0,0,0);CHKERRQ(ierr);
4045     if (mat->ops->assemblybegin){ierr = (*mat->ops->assemblybegin)(mat,type);CHKERRQ(ierr);}
4046     ierr = PetscLogEventEnd(MAT_AssemblyBegin,mat,0,0,0);CHKERRQ(ierr);
4047   } else {
4048     if (mat->ops->assemblybegin){ierr = (*mat->ops->assemblybegin)(mat,type);CHKERRQ(ierr);}
4049   }
4050   PetscFunctionReturn(0);
4051 }
4052 
4053 #undef __FUNCT__
4054 #define __FUNCT__ "MatAssembed"
4055 /*@
4056    MatAssembled - Indicates if a matrix has been assembled and is ready for
4057      use; for example, in matrix-vector product.
4058 
4059    Collective on Mat
4060 
4061    Input Parameter:
4062 .  mat - the matrix
4063 
4064    Output Parameter:
4065 .  assembled - PETSC_TRUE or PETSC_FALSE
4066 
4067    Level: advanced
4068 
4069    Concepts: matrices^assembled?
4070 
4071 .seealso: MatAssemblyEnd(), MatSetValues(), MatAssemblyBegin()
4072 @*/
4073 PetscErrorCode PETSCMAT_DLLEXPORT MatAssembled(Mat mat,PetscTruth *assembled)
4074 {
4075   PetscFunctionBegin;
4076   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4077   PetscValidType(mat,1);
4078   PetscValidPointer(assembled,2);
4079   *assembled = mat->assembled;
4080   PetscFunctionReturn(0);
4081 }
4082 
4083 #undef __FUNCT__
4084 #define __FUNCT__ "MatView_Private"
4085 /*
4086     Processes command line options to determine if/how a matrix
4087   is to be viewed. Called by MatAssemblyEnd() and MatLoad().
4088 */
4089 PetscErrorCode MatView_Private(Mat mat)
4090 {
4091   PetscErrorCode    ierr;
4092   PetscTruth        flg1,flg2,flg3,flg4,flg6,flg7,flg8;
4093   static PetscTruth incall = PETSC_FALSE;
4094 #if defined(PETSC_USE_SOCKET_VIEWER)
4095   PetscTruth        flg5;
4096 #endif
4097 
4098   PetscFunctionBegin;
4099   if (incall) PetscFunctionReturn(0);
4100   incall = PETSC_TRUE;
4101   ierr = PetscOptionsBegin(((PetscObject)mat)->comm,((PetscObject)mat)->prefix,"Matrix Options","Mat");CHKERRQ(ierr);
4102     ierr = PetscOptionsName("-mat_view_info","Information on matrix size","MatView",&flg1);CHKERRQ(ierr);
4103     ierr = PetscOptionsName("-mat_view_info_detailed","Nonzeros in the matrix","MatView",&flg2);CHKERRQ(ierr);
4104     ierr = PetscOptionsName("-mat_view","Print matrix to stdout","MatView",&flg3);CHKERRQ(ierr);
4105     ierr = PetscOptionsName("-mat_view_matlab","Print matrix to stdout in a format Matlab can read","MatView",&flg4);CHKERRQ(ierr);
4106 #if defined(PETSC_USE_SOCKET_VIEWER)
4107     ierr = PetscOptionsName("-mat_view_socket","Send matrix to socket (can be read from matlab)","MatView",&flg5);CHKERRQ(ierr);
4108 #endif
4109     ierr = PetscOptionsName("-mat_view_binary","Save matrix to file in binary format","MatView",&flg6);CHKERRQ(ierr);
4110     ierr = PetscOptionsName("-mat_view_draw","Draw the matrix nonzero structure","MatView",&flg7);CHKERRQ(ierr);
4111   ierr = PetscOptionsEnd();CHKERRQ(ierr);
4112 
4113   if (flg1) {
4114     PetscViewer viewer;
4115 
4116     ierr = PetscViewerASCIIGetStdout(((PetscObject)mat)->comm,&viewer);CHKERRQ(ierr);
4117     ierr = PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_INFO);CHKERRQ(ierr);
4118     ierr = MatView(mat,viewer);CHKERRQ(ierr);
4119     ierr = PetscViewerPopFormat(viewer);CHKERRQ(ierr);
4120   }
4121   if (flg2) {
4122     PetscViewer viewer;
4123 
4124     ierr = PetscViewerASCIIGetStdout(((PetscObject)mat)->comm,&viewer);CHKERRQ(ierr);
4125     ierr = PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_INFO_DETAIL);CHKERRQ(ierr);
4126     ierr = MatView(mat,viewer);CHKERRQ(ierr);
4127     ierr = PetscViewerPopFormat(viewer);CHKERRQ(ierr);
4128   }
4129   if (flg3) {
4130     PetscViewer viewer;
4131 
4132     ierr = PetscViewerASCIIGetStdout(((PetscObject)mat)->comm,&viewer);CHKERRQ(ierr);
4133     ierr = MatView(mat,viewer);CHKERRQ(ierr);
4134   }
4135   if (flg4) {
4136     PetscViewer viewer;
4137 
4138     ierr = PetscViewerASCIIGetStdout(((PetscObject)mat)->comm,&viewer);CHKERRQ(ierr);
4139     ierr = PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_MATLAB);CHKERRQ(ierr);
4140     ierr = MatView(mat,viewer);CHKERRQ(ierr);
4141     ierr = PetscViewerPopFormat(viewer);CHKERRQ(ierr);
4142   }
4143 #if defined(PETSC_USE_SOCKET_VIEWER)
4144   if (flg5) {
4145     ierr = MatView(mat,PETSC_VIEWER_SOCKET_(((PetscObject)mat)->comm));CHKERRQ(ierr);
4146     ierr = PetscViewerFlush(PETSC_VIEWER_SOCKET_(((PetscObject)mat)->comm));CHKERRQ(ierr);
4147   }
4148 #endif
4149   if (flg6) {
4150     ierr = MatView(mat,PETSC_VIEWER_BINARY_(((PetscObject)mat)->comm));CHKERRQ(ierr);
4151     ierr = PetscViewerFlush(PETSC_VIEWER_BINARY_(((PetscObject)mat)->comm));CHKERRQ(ierr);
4152   }
4153   if (flg7) {
4154     ierr = PetscOptionsHasName(((PetscObject)mat)->prefix,"-mat_view_contour",&flg8);CHKERRQ(ierr);
4155     if (flg8) {
4156       PetscViewerPushFormat(PETSC_VIEWER_DRAW_(((PetscObject)mat)->comm),PETSC_VIEWER_DRAW_CONTOUR);CHKERRQ(ierr);
4157     }
4158     ierr = MatView(mat,PETSC_VIEWER_DRAW_(((PetscObject)mat)->comm));CHKERRQ(ierr);
4159     ierr = PetscViewerFlush(PETSC_VIEWER_DRAW_(((PetscObject)mat)->comm));CHKERRQ(ierr);
4160     if (flg8) {
4161       PetscViewerPopFormat(PETSC_VIEWER_DRAW_(((PetscObject)mat)->comm));CHKERRQ(ierr);
4162     }
4163   }
4164   incall = PETSC_FALSE;
4165   PetscFunctionReturn(0);
4166 }
4167 
4168 #undef __FUNCT__
4169 #define __FUNCT__ "MatAssemblyEnd"
4170 /*@
4171    MatAssemblyEnd - Completes assembling the matrix.  This routine should
4172    be called after MatAssemblyBegin().
4173 
4174    Collective on Mat
4175 
4176    Input Parameters:
4177 +  mat - the matrix
4178 -  type - type of assembly, either MAT_FLUSH_ASSEMBLY or MAT_FINAL_ASSEMBLY
4179 
4180    Options Database Keys:
4181 +  -mat_view_info - Prints info on matrix at conclusion of MatEndAssembly()
4182 .  -mat_view_info_detailed - Prints more detailed info
4183 .  -mat_view - Prints matrix in ASCII format
4184 .  -mat_view_matlab - Prints matrix in Matlab format
4185 .  -mat_view_draw - PetscDraws nonzero structure of matrix, using MatView() and PetscDrawOpenX().
4186 .  -display <name> - Sets display name (default is host)
4187 .  -draw_pause <sec> - Sets number of seconds to pause after display
4188 .  -mat_view_socket - Sends matrix to socket, can be accessed from Matlab (see users manual)
4189 .  -viewer_socket_machine <machine>
4190 .  -viewer_socket_port <port>
4191 .  -mat_view_binary - save matrix to file in binary format
4192 -  -viewer_binary_filename <name>
4193 
4194    Notes:
4195    MatSetValues() generally caches the values.  The matrix is ready to
4196    use only after MatAssemblyBegin() and MatAssemblyEnd() have been called.
4197    Use MAT_FLUSH_ASSEMBLY when switching between ADD_VALUES and INSERT_VALUES
4198    in MatSetValues(); use MAT_FINAL_ASSEMBLY for the final assembly before
4199    using the matrix.
4200 
4201    Level: beginner
4202 
4203 .seealso: MatAssemblyBegin(), MatSetValues(), PetscDrawOpenX(), MatView(), MatAssembled(), PetscViewerSocketOpen()
4204 @*/
4205 PetscErrorCode PETSCMAT_DLLEXPORT MatAssemblyEnd(Mat mat,MatAssemblyType type)
4206 {
4207   PetscErrorCode  ierr;
4208   static PetscInt inassm = 0;
4209   PetscTruth      flg;
4210 
4211   PetscFunctionBegin;
4212   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4213   PetscValidType(mat,1);
4214 
4215   inassm++;
4216   MatAssemblyEnd_InUse++;
4217   if (MatAssemblyEnd_InUse == 1) { /* Do the logging only the first time through */
4218     ierr = PetscLogEventBegin(MAT_AssemblyEnd,mat,0,0,0);CHKERRQ(ierr);
4219     if (mat->ops->assemblyend) {
4220       ierr = (*mat->ops->assemblyend)(mat,type);CHKERRQ(ierr);
4221     }
4222     ierr = PetscLogEventEnd(MAT_AssemblyEnd,mat,0,0,0);CHKERRQ(ierr);
4223   } else {
4224     if (mat->ops->assemblyend) {
4225       ierr = (*mat->ops->assemblyend)(mat,type);CHKERRQ(ierr);
4226     }
4227   }
4228 
4229   /* Flush assembly is not a true assembly */
4230   if (type != MAT_FLUSH_ASSEMBLY) {
4231     mat->assembled  = PETSC_TRUE; mat->num_ass++;
4232   }
4233   mat->insertmode = NOT_SET_VALUES;
4234   MatAssemblyEnd_InUse--;
4235   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
4236   if (!mat->symmetric_eternal) {
4237     mat->symmetric_set              = PETSC_FALSE;
4238     mat->hermitian_set              = PETSC_FALSE;
4239     mat->structurally_symmetric_set = PETSC_FALSE;
4240   }
4241   if (inassm == 1 && type != MAT_FLUSH_ASSEMBLY) {
4242     ierr = MatView_Private(mat);CHKERRQ(ierr);
4243     ierr = PetscOptionsHasName(((PetscObject)mat)->prefix,"-mat_is_symmetric",&flg);CHKERRQ(ierr);
4244     if (flg) {
4245       PetscReal tol = 0.0;
4246       ierr = PetscOptionsGetReal(((PetscObject)mat)->prefix,"-mat_is_symmetric",&tol,PETSC_NULL);CHKERRQ(ierr);
4247       ierr = MatIsSymmetric(mat,tol,&flg);CHKERRQ(ierr);
4248       if (flg) {
4249         ierr = PetscPrintf(((PetscObject)mat)->comm,"Matrix is symmetric (tolerance %G)\n",tol);CHKERRQ(ierr);
4250       } else {
4251         ierr = PetscPrintf(((PetscObject)mat)->comm,"Matrix is not symmetric (tolerance %G)\n",tol);CHKERRQ(ierr);
4252       }
4253     }
4254   }
4255   inassm--;
4256   PetscFunctionReturn(0);
4257 }
4258 
4259 
4260 #undef __FUNCT__
4261 #define __FUNCT__ "MatCompress"
4262 /*@
4263    MatCompress - Tries to store the matrix in as little space as
4264    possible.  May fail if memory is already fully used, since it
4265    tries to allocate new space.
4266 
4267    Collective on Mat
4268 
4269    Input Parameters:
4270 .  mat - the matrix
4271 
4272    Level: advanced
4273 
4274 @*/
4275 PetscErrorCode PETSCMAT_DLLEXPORT MatCompress(Mat mat)
4276 {
4277   PetscErrorCode ierr;
4278 
4279   PetscFunctionBegin;
4280   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4281   PetscValidType(mat,1);
4282   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4283   if (mat->ops->compress) {ierr = (*mat->ops->compress)(mat);CHKERRQ(ierr);}
4284   PetscFunctionReturn(0);
4285 }
4286 
4287 #undef __FUNCT__
4288 #define __FUNCT__ "MatSetOption"
4289 /*@
4290    MatSetOption - Sets a parameter option for a matrix. Some options
4291    may be specific to certain storage formats.  Some options
4292    determine how values will be inserted (or added). Sorted,
4293    row-oriented input will generally assemble the fastest. The default
4294    is row-oriented, nonsorted input.
4295 
4296    Collective on Mat
4297 
4298    Input Parameters:
4299 +  mat - the matrix
4300 .  option - the option, one of those listed below (and possibly others),
4301 -  flg - turn the option on (PETSC_TRUE) or off (PETSC_FALSE)
4302 
4303   Options Describing Matrix Structure:
4304 +    MAT_SYMMETRIC - symmetric in terms of both structure and value
4305 .    MAT_HERMITIAN - transpose is the complex conjugation
4306 .    MAT_STRUCTURALLY_SYMMETRIC - symmetric nonzero structure
4307 -    MAT_SYMMETRY_ETERNAL - if you would like the symmetry/Hermitian flag
4308                             you set to be kept with all future use of the matrix
4309                             including after MatAssemblyBegin/End() which could
4310                             potentially change the symmetry structure, i.e. you
4311                             KNOW the matrix will ALWAYS have the property you set.
4312 
4313 
4314    Options For Use with MatSetValues():
4315    Insert a logically dense subblock, which can be
4316 .    MAT_ROW_ORIENTED - row-oriented (default)
4317 
4318    Note these options reflect the data you pass in with MatSetValues(); it has
4319    nothing to do with how the data is stored internally in the matrix
4320    data structure.
4321 
4322    When (re)assembling a matrix, we can restrict the input for
4323    efficiency/debugging purposes.  These options include
4324 +    MAT_NEW_NONZERO_LOCATIONS - additional insertions will be
4325         allowed if they generate a new nonzero
4326 .    MAT_NEW_DIAGONALS - new diagonals will be allowed (for block diagonal format only)
4327 .    MAT_IGNORE_OFF_PROC_ENTRIES - drops off-processor entries
4328 .    MAT_NEW_NONZERO_LOCATION_ERR - generates an error for new matrix entry
4329 -    MAT_USE_HASH_TABLE - uses a hash table to speed up matrix assembly
4330 
4331    Notes:
4332    Some options are relevant only for particular matrix types and
4333    are thus ignored by others.  Other options are not supported by
4334    certain matrix types and will generate an error message if set.
4335 
4336    If using a Fortran 77 module to compute a matrix, one may need to
4337    use the column-oriented option (or convert to the row-oriented
4338    format).
4339 
4340    MAT_NEW_NONZERO_LOCATIONS set to PETSC_FALSE indicates that any add or insertion
4341    that would generate a new entry in the nonzero structure is instead
4342    ignored.  Thus, if memory has not alredy been allocated for this particular
4343    data, then the insertion is ignored. For dense matrices, in which
4344    the entire array is allocated, no entries are ever ignored.
4345    Set after the first MatAssemblyEnd()
4346 
4347    MAT_NEW_NONZERO_LOCATION_ERR indicates that any add or insertion
4348    that would generate a new entry in the nonzero structure instead produces
4349    an error. (Currently supported for AIJ and BAIJ formats only.)
4350    This is a useful flag when using SAME_NONZERO_PATTERN in calling
4351    KSPSetOperators() to ensure that the nonzero pattern truely does
4352    remain unchanged. Set after the first MatAssemblyEnd()
4353 
4354    MAT_NEW_NONZERO_ALLOCATION_ERR indicates that any add or insertion
4355    that would generate a new entry that has not been preallocated will
4356    instead produce an error. (Currently supported for AIJ and BAIJ formats
4357    only.) This is a useful flag when debugging matrix memory preallocation.
4358 
4359    MAT_IGNORE_OFF_PROC_ENTRIES indicates entries destined for
4360    other processors should be dropped, rather than stashed.
4361    This is useful if you know that the "owning" processor is also
4362    always generating the correct matrix entries, so that PETSc need
4363    not transfer duplicate entries generated on another processor.
4364 
4365    MAT_USE_HASH_TABLE indicates that a hash table be used to improve the
4366    searches during matrix assembly. When this flag is set, the hash table
4367    is created during the first Matrix Assembly. This hash table is
4368    used the next time through, during MatSetVaules()/MatSetVaulesBlocked()
4369    to improve the searching of indices. MAT_NEW_NONZERO_LOCATIONS flag
4370    should be used with MAT_USE_HASH_TABLE flag. This option is currently
4371    supported by MATMPIBAIJ format only.
4372 
4373    MAT_KEEP_ZEROED_ROWS indicates when MatZeroRows() is called the zeroed entries
4374    are kept in the nonzero structure
4375 
4376    MAT_IGNORE_ZERO_ENTRIES - for AIJ/IS matrices this will stop zero values from creating
4377    a zero location in the matrix
4378 
4379    MAT_USE_INODES - indicates using inode version of the code - works with AIJ and
4380    ROWBS matrix types
4381 
4382    Level: intermediate
4383 
4384    Concepts: matrices^setting options
4385 
4386 @*/
4387 PetscErrorCode PETSCMAT_DLLEXPORT MatSetOption(Mat mat,MatOption op,PetscTruth flg)
4388 {
4389   PetscErrorCode ierr;
4390 
4391   PetscFunctionBegin;
4392   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4393   PetscValidType(mat,1);
4394   if (((int) op) < 0 || ((int) op) > 16) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Options %d is out of range",(int)op);
4395   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4396   switch (op) {
4397   case MAT_SYMMETRIC:
4398     mat->symmetric                  = flg;
4399     if (flg) mat->structurally_symmetric     = PETSC_TRUE;
4400     mat->symmetric_set              = PETSC_TRUE;
4401     mat->structurally_symmetric_set = flg;
4402     break;
4403   case MAT_HERMITIAN:
4404     mat->hermitian                  = flg;
4405     if (flg) mat->structurally_symmetric     = PETSC_TRUE;
4406     mat->hermitian_set              = PETSC_TRUE;
4407     mat->structurally_symmetric_set = flg;
4408     break;
4409   case MAT_STRUCTURALLY_SYMMETRIC:
4410     mat->structurally_symmetric     = flg;
4411     mat->structurally_symmetric_set = PETSC_TRUE;
4412     break;
4413   case MAT_SYMMETRY_ETERNAL:
4414     mat->symmetric_eternal          = flg;
4415     break;
4416   default:
4417     break;
4418   }
4419   if (mat->ops->setoption) {
4420     ierr = (*mat->ops->setoption)(mat,op,flg);CHKERRQ(ierr);
4421   }
4422   PetscFunctionReturn(0);
4423 }
4424 
4425 #undef __FUNCT__
4426 #define __FUNCT__ "MatZeroEntries"
4427 /*@
4428    MatZeroEntries - Zeros all entries of a matrix.  For sparse matrices
4429    this routine retains the old nonzero structure.
4430 
4431    Collective on Mat
4432 
4433    Input Parameters:
4434 .  mat - the matrix
4435 
4436    Level: intermediate
4437 
4438    Concepts: matrices^zeroing
4439 
4440 .seealso: MatZeroRows()
4441 @*/
4442 PetscErrorCode PETSCMAT_DLLEXPORT MatZeroEntries(Mat mat)
4443 {
4444   PetscErrorCode ierr;
4445 
4446   PetscFunctionBegin;
4447   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4448   PetscValidType(mat,1);
4449   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4450   if (mat->insertmode != NOT_SET_VALUES) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for matrices where you have set values but not yet assembled");
4451   if (!mat->ops->zeroentries) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
4452   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4453 
4454   ierr = PetscLogEventBegin(MAT_ZeroEntries,mat,0,0,0);CHKERRQ(ierr);
4455   ierr = (*mat->ops->zeroentries)(mat);CHKERRQ(ierr);
4456   ierr = PetscLogEventEnd(MAT_ZeroEntries,mat,0,0,0);CHKERRQ(ierr);
4457   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
4458   PetscFunctionReturn(0);
4459 }
4460 
4461 #undef __FUNCT__
4462 #define __FUNCT__ "MatZeroRows"
4463 /*@C
4464    MatZeroRows - Zeros all entries (except possibly the main diagonal)
4465    of a set of rows of a matrix.
4466 
4467    Collective on Mat
4468 
4469    Input Parameters:
4470 +  mat - the matrix
4471 .  numRows - the number of rows to remove
4472 .  rows - the global row indices
4473 -  diag - value put in all diagonals of eliminated rows
4474 
4475    Notes:
4476    For the AIJ and BAIJ matrix formats this removes the old nonzero structure,
4477    but does not release memory.  For the dense and block diagonal
4478    formats this does not alter the nonzero structure.
4479 
4480    If the option MatSetOption(mat,MAT_KEEP_ZEROED_ROWS,PETSC_TRUE) the nonzero structure
4481    of the matrix is not changed (even for AIJ and BAIJ matrices) the values are
4482    merely zeroed.
4483 
4484    The user can set a value in the diagonal entry (or for the AIJ and
4485    row formats can optionally remove the main diagonal entry from the
4486    nonzero structure as well, by passing 0.0 as the final argument).
4487 
4488    For the parallel case, all processes that share the matrix (i.e.,
4489    those in the communicator used for matrix creation) MUST call this
4490    routine, regardless of whether any rows being zeroed are owned by
4491    them.
4492 
4493    Each processor should list the rows that IT wants zeroed
4494 
4495    Level: intermediate
4496 
4497    Concepts: matrices^zeroing rows
4498 
4499 .seealso: MatZeroRowsIS(), MatZeroEntries(), MatZeroRowsLocal(), MatSetOption()
4500 @*/
4501 PetscErrorCode PETSCMAT_DLLEXPORT MatZeroRows(Mat mat,PetscInt numRows,const PetscInt rows[],PetscScalar diag)
4502 {
4503   PetscErrorCode ierr;
4504 
4505   PetscFunctionBegin;
4506   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4507   PetscValidType(mat,1);
4508   if (numRows) PetscValidIntPointer(rows,3);
4509   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4510   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4511   if (!mat->ops->zerorows) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
4512   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4513 
4514   ierr = (*mat->ops->zerorows)(mat,numRows,rows,diag);CHKERRQ(ierr);
4515   ierr = MatView_Private(mat);CHKERRQ(ierr);
4516   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
4517   PetscFunctionReturn(0);
4518 }
4519 
4520 #undef __FUNCT__
4521 #define __FUNCT__ "MatZeroRowsIS"
4522 /*@C
4523    MatZeroRowsIS - Zeros all entries (except possibly the main diagonal)
4524    of a set of rows of a matrix.
4525 
4526    Collective on Mat
4527 
4528    Input Parameters:
4529 +  mat - the matrix
4530 .  is - index set of rows to remove
4531 -  diag - value put in all diagonals of eliminated rows
4532 
4533    Notes:
4534    For the AIJ and BAIJ matrix formats this removes the old nonzero structure,
4535    but does not release memory.  For the dense and block diagonal
4536    formats this does not alter the nonzero structure.
4537 
4538    If the option MatSetOption(mat,MAT_KEEP_ZEROED_ROWS,PETSC_TRUE) the nonzero structure
4539    of the matrix is not changed (even for AIJ and BAIJ matrices) the values are
4540    merely zeroed.
4541 
4542    The user can set a value in the diagonal entry (or for the AIJ and
4543    row formats can optionally remove the main diagonal entry from the
4544    nonzero structure as well, by passing 0.0 as the final argument).
4545 
4546    For the parallel case, all processes that share the matrix (i.e.,
4547    those in the communicator used for matrix creation) MUST call this
4548    routine, regardless of whether any rows being zeroed are owned by
4549    them.
4550 
4551    Each processor should list the rows that IT wants zeroed
4552 
4553    Level: intermediate
4554 
4555    Concepts: matrices^zeroing rows
4556 
4557 .seealso: MatZeroRows(), MatZeroEntries(), MatZeroRowsLocal(), MatSetOption()
4558 @*/
4559 PetscErrorCode PETSCMAT_DLLEXPORT MatZeroRowsIS(Mat mat,IS is,PetscScalar diag)
4560 {
4561   PetscInt       numRows;
4562   PetscInt       *rows;
4563   PetscErrorCode ierr;
4564 
4565   PetscFunctionBegin;
4566   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4567   PetscValidType(mat,1);
4568   PetscValidHeaderSpecific(is,IS_COOKIE,2);
4569   ierr = ISGetLocalSize(is,&numRows);CHKERRQ(ierr);
4570   ierr = ISGetIndices(is,&rows);CHKERRQ(ierr);
4571   ierr = MatZeroRows(mat,numRows,rows,diag);CHKERRQ(ierr);
4572   ierr = ISRestoreIndices(is,&rows);CHKERRQ(ierr);
4573   PetscFunctionReturn(0);
4574 }
4575 
4576 #undef __FUNCT__
4577 #define __FUNCT__ "MatZeroRowsLocal"
4578 /*@C
4579    MatZeroRowsLocal - Zeros all entries (except possibly the main diagonal)
4580    of a set of rows of a matrix; using local numbering of rows.
4581 
4582    Collective on Mat
4583 
4584    Input Parameters:
4585 +  mat - the matrix
4586 .  numRows - the number of rows to remove
4587 .  rows - the global row indices
4588 -  diag - value put in all diagonals of eliminated rows
4589 
4590    Notes:
4591    Before calling MatZeroRowsLocal(), the user must first set the
4592    local-to-global mapping by calling MatSetLocalToGlobalMapping().
4593 
4594    For the AIJ matrix formats this removes the old nonzero structure,
4595    but does not release memory.  For the dense and block diagonal
4596    formats this does not alter the nonzero structure.
4597 
4598    If the option MatSetOption(mat,MAT_KEEP_ZEROED_ROWS,PETSC_TRUE) the nonzero structure
4599    of the matrix is not changed (even for AIJ and BAIJ matrices) the values are
4600    merely zeroed.
4601 
4602    The user can set a value in the diagonal entry (or for the AIJ and
4603    row formats can optionally remove the main diagonal entry from the
4604    nonzero structure as well, by passing 0.0 as the final argument).
4605 
4606    Level: intermediate
4607 
4608    Concepts: matrices^zeroing
4609 
4610 .seealso: MatZeroRows(), MatZeroRowsLocalIS(), MatZeroEntries(), MatZeroRows(), MatSetLocalToGlobalMapping
4611 @*/
4612 PetscErrorCode PETSCMAT_DLLEXPORT MatZeroRowsLocal(Mat mat,PetscInt numRows,const PetscInt rows[],PetscScalar diag)
4613 {
4614   PetscErrorCode ierr;
4615 
4616   PetscFunctionBegin;
4617   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4618   PetscValidType(mat,1);
4619   if (numRows) PetscValidIntPointer(rows,3);
4620   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4621   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4622   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4623 
4624   if (mat->ops->zerorowslocal) {
4625     ierr = (*mat->ops->zerorowslocal)(mat,numRows,rows,diag);CHKERRQ(ierr);
4626   } else {
4627     IS is, newis;
4628     PetscInt *newRows;
4629 
4630     if (!mat->mapping) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Need to provide local to global mapping to matrix first");
4631     ierr = ISCreateGeneral(PETSC_COMM_SELF,numRows,rows,&is);CHKERRQ(ierr);
4632     ierr = ISLocalToGlobalMappingApplyIS(mat->mapping,is,&newis);CHKERRQ(ierr);
4633     ierr = ISGetIndices(newis,&newRows);CHKERRQ(ierr);
4634     ierr = (*mat->ops->zerorows)(mat,numRows,newRows,diag);CHKERRQ(ierr);
4635     ierr = ISRestoreIndices(newis,&newRows);CHKERRQ(ierr);
4636     ierr = ISDestroy(newis);CHKERRQ(ierr);
4637     ierr = ISDestroy(is);CHKERRQ(ierr);
4638   }
4639   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
4640   PetscFunctionReturn(0);
4641 }
4642 
4643 #undef __FUNCT__
4644 #define __FUNCT__ "MatZeroRowsLocalIS"
4645 /*@C
4646    MatZeroRowsLocalIS - Zeros all entries (except possibly the main diagonal)
4647    of a set of rows of a matrix; using local numbering of rows.
4648 
4649    Collective on Mat
4650 
4651    Input Parameters:
4652 +  mat - the matrix
4653 .  is - index set of rows to remove
4654 -  diag - value put in all diagonals of eliminated rows
4655 
4656    Notes:
4657    Before calling MatZeroRowsLocalIS(), the user must first set the
4658    local-to-global mapping by calling MatSetLocalToGlobalMapping().
4659 
4660    For the AIJ matrix formats this removes the old nonzero structure,
4661    but does not release memory.  For the dense and block diagonal
4662    formats this does not alter the nonzero structure.
4663 
4664    If the option MatSetOption(mat,MAT_KEEP_ZEROED_ROWS,PETSC_TRUE) the nonzero structure
4665    of the matrix is not changed (even for AIJ and BAIJ matrices) the values are
4666    merely zeroed.
4667 
4668    The user can set a value in the diagonal entry (or for the AIJ and
4669    row formats can optionally remove the main diagonal entry from the
4670    nonzero structure as well, by passing 0.0 as the final argument).
4671 
4672    Level: intermediate
4673 
4674    Concepts: matrices^zeroing
4675 
4676 .seealso: MatZeroRows(), MatZeroRowsLocal(), MatZeroEntries(), MatZeroRows(), MatSetLocalToGlobalMapping
4677 @*/
4678 PetscErrorCode PETSCMAT_DLLEXPORT MatZeroRowsLocalIS(Mat mat,IS is,PetscScalar diag)
4679 {
4680   PetscErrorCode ierr;
4681   PetscInt       numRows;
4682   PetscInt       *rows;
4683 
4684   PetscFunctionBegin;
4685   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4686   PetscValidType(mat,1);
4687   PetscValidHeaderSpecific(is,IS_COOKIE,2);
4688   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4689   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4690   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4691 
4692   ierr = ISGetLocalSize(is,&numRows);CHKERRQ(ierr);
4693   ierr = ISGetIndices(is,&rows);CHKERRQ(ierr);
4694   ierr = MatZeroRowsLocal(mat,numRows,rows,diag);CHKERRQ(ierr);
4695   ierr = ISRestoreIndices(is,&rows);CHKERRQ(ierr);
4696   PetscFunctionReturn(0);
4697 }
4698 
4699 #undef __FUNCT__
4700 #define __FUNCT__ "MatGetSize"
4701 /*@
4702    MatGetSize - Returns the numbers of rows and columns in a matrix.
4703 
4704    Not Collective
4705 
4706    Input Parameter:
4707 .  mat - the matrix
4708 
4709    Output Parameters:
4710 +  m - the number of global rows
4711 -  n - the number of global columns
4712 
4713    Note: both output parameters can be PETSC_NULL on input.
4714 
4715    Level: beginner
4716 
4717    Concepts: matrices^size
4718 
4719 .seealso: MatGetLocalSize()
4720 @*/
4721 PetscErrorCode PETSCMAT_DLLEXPORT MatGetSize(Mat mat,PetscInt *m,PetscInt* n)
4722 {
4723   PetscFunctionBegin;
4724   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4725   if (m) *m = mat->rmap.N;
4726   if (n) *n = mat->cmap.N;
4727   PetscFunctionReturn(0);
4728 }
4729 
4730 #undef __FUNCT__
4731 #define __FUNCT__ "MatGetLocalSize"
4732 /*@
4733    MatGetLocalSize - Returns the number of rows and columns in a matrix
4734    stored locally.  This information may be implementation dependent, so
4735    use with care.
4736 
4737    Not Collective
4738 
4739    Input Parameters:
4740 .  mat - the matrix
4741 
4742    Output Parameters:
4743 +  m - the number of local rows
4744 -  n - the number of local columns
4745 
4746    Note: both output parameters can be PETSC_NULL on input.
4747 
4748    Level: beginner
4749 
4750    Concepts: matrices^local size
4751 
4752 .seealso: MatGetSize()
4753 @*/
4754 PetscErrorCode PETSCMAT_DLLEXPORT MatGetLocalSize(Mat mat,PetscInt *m,PetscInt* n)
4755 {
4756   PetscFunctionBegin;
4757   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4758   if (m) PetscValidIntPointer(m,2);
4759   if (n) PetscValidIntPointer(n,3);
4760   if (m) *m = mat->rmap.n;
4761   if (n) *n = mat->cmap.n;
4762   PetscFunctionReturn(0);
4763 }
4764 
4765 #undef __FUNCT__
4766 #define __FUNCT__ "MatGetOwnershipRangeColumn"
4767 /*@
4768    MatGetOwnershipRangeColumn - Returns the range of matrix columns owned by
4769    this processor.
4770 
4771    Not Collective
4772 
4773    Input Parameters:
4774 .  mat - the matrix
4775 
4776    Output Parameters:
4777 +  m - the global index of the first local column
4778 -  n - one more than the global index of the last local column
4779 
4780    Notes: both output parameters can be PETSC_NULL on input.
4781 
4782    Level: developer
4783 
4784    Concepts: matrices^column ownership
4785 @*/
4786 PetscErrorCode PETSCMAT_DLLEXPORT MatGetOwnershipRangeColumn(Mat mat,PetscInt *m,PetscInt* n)
4787 {
4788   PetscErrorCode ierr;
4789 
4790   PetscFunctionBegin;
4791   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4792   PetscValidType(mat,1);
4793   if (m) PetscValidIntPointer(m,2);
4794   if (n) PetscValidIntPointer(n,3);
4795   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4796   if (m) *m = mat->cmap.rstart;
4797   if (n) *n = mat->cmap.rend;
4798   PetscFunctionReturn(0);
4799 }
4800 
4801 #undef __FUNCT__
4802 #define __FUNCT__ "MatGetOwnershipRange"
4803 /*@
4804    MatGetOwnershipRange - Returns the range of matrix rows owned by
4805    this processor, assuming that the matrix is laid out with the first
4806    n1 rows on the first processor, the next n2 rows on the second, etc.
4807    For certain parallel layouts this range may not be well defined.
4808 
4809    Not Collective
4810 
4811    Input Parameters:
4812 .  mat - the matrix
4813 
4814    Output Parameters:
4815 +  m - the global index of the first local row
4816 -  n - one more than the global index of the last local row
4817 
4818    Note: both output parameters can be PETSC_NULL on input.
4819 
4820    Level: beginner
4821 
4822    Concepts: matrices^row ownership
4823 
4824 .seealso:   MatGetOwnershipRanges()
4825 
4826 @*/
4827 PetscErrorCode PETSCMAT_DLLEXPORT MatGetOwnershipRange(Mat mat,PetscInt *m,PetscInt* n)
4828 {
4829   PetscErrorCode ierr;
4830 
4831   PetscFunctionBegin;
4832   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4833   PetscValidType(mat,1);
4834   if (m) PetscValidIntPointer(m,2);
4835   if (n) PetscValidIntPointer(n,3);
4836   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4837   if (m) *m = mat->rmap.rstart;
4838   if (n) *n = mat->rmap.rend;
4839   PetscFunctionReturn(0);
4840 }
4841 
4842 #undef __FUNCT__
4843 #define __FUNCT__ "MatGetOwnershipRanges"
4844 /*@C
4845    MatGetOwnershipRanges - Returns the range of matrix rows owned by
4846    each process
4847 
4848    Not Collective
4849 
4850    Input Parameters:
4851 .  mat - the matrix
4852 
4853    Output Parameters:
4854 .  ranges - start of each processors portion plus one more then the total length at the end
4855 
4856    Level: beginner
4857 
4858    Concepts: matrices^row ownership
4859 
4860 .seealso:   MatGetOwnershipRange()
4861 
4862 @*/
4863 PetscErrorCode PETSCMAT_DLLEXPORT MatGetOwnershipRanges(Mat mat,const PetscInt **ranges)
4864 {
4865   PetscErrorCode ierr;
4866 
4867   PetscFunctionBegin;
4868   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4869   PetscValidType(mat,1);
4870   ierr = PetscMapGetGlobalRange(&mat->rmap,ranges);CHKERRQ(ierr);
4871   PetscFunctionReturn(0);
4872 }
4873 
4874 #undef __FUNCT__
4875 #define __FUNCT__ "MatILUFactorSymbolic"
4876 /*@
4877    MatILUFactorSymbolic - Performs symbolic ILU factorization of a matrix.
4878    Uses levels of fill only, not drop tolerance. Use MatLUFactorNumeric()
4879    to complete the factorization.
4880 
4881    Collective on Mat
4882 
4883    Input Parameters:
4884 +  mat - the matrix
4885 .  row - row permutation
4886 .  column - column permutation
4887 -  info - structure containing
4888 $      levels - number of levels of fill.
4889 $      expected fill - as ratio of original fill.
4890 $      1 or 0 - indicating force fill on diagonal (improves robustness for matrices
4891                 missing diagonal entries)
4892 
4893    Output Parameters:
4894 .  fact - new matrix that has been symbolically factored
4895 
4896    Notes:
4897    See the users manual for additional information about
4898    choosing the fill factor for better efficiency.
4899 
4900    Most users should employ the simplified KSP interface for linear solvers
4901    instead of working directly with matrix algebra routines such as this.
4902    See, e.g., KSPCreate().
4903 
4904    Level: developer
4905 
4906   Concepts: matrices^symbolic LU factorization
4907   Concepts: matrices^factorization
4908   Concepts: LU^symbolic factorization
4909 
4910 .seealso: MatLUFactorSymbolic(), MatLUFactorNumeric(), MatCholeskyFactor()
4911           MatGetOrdering(), MatFactorInfo
4912 
4913 @*/
4914 PetscErrorCode PETSCMAT_DLLEXPORT MatILUFactorSymbolic(Mat mat,IS row,IS col,MatFactorInfo *info,Mat *fact)
4915 {
4916   PetscErrorCode ierr;
4917 
4918   PetscFunctionBegin;
4919   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4920   PetscValidType(mat,1);
4921   PetscValidHeaderSpecific(row,IS_COOKIE,2);
4922   PetscValidHeaderSpecific(col,IS_COOKIE,3);
4923   PetscValidPointer(info,4);
4924   PetscValidPointer(fact,5);
4925   if (info->levels < 0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Levels of fill negative %D",(PetscInt)info->levels);
4926   if (info->fill < 1.0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Expected fill less than 1.0 %G",info->fill);
4927   if (!mat->ops->ilufactorsymbolic) SETERRQ1(PETSC_ERR_SUP,"Matrix type %s  symbolic ILU",((PetscObject)mat)->type_name);
4928   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4929   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4930   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4931 
4932   ierr = PetscLogEventBegin(MAT_ILUFactorSymbolic,mat,row,col,0);CHKERRQ(ierr);
4933   ierr = (*mat->ops->ilufactorsymbolic)(mat,row,col,info,fact);CHKERRQ(ierr);
4934   ierr = PetscLogEventEnd(MAT_ILUFactorSymbolic,mat,row,col,0);CHKERRQ(ierr);
4935   PetscFunctionReturn(0);
4936 }
4937 
4938 #undef __FUNCT__
4939 #define __FUNCT__ "MatICCFactorSymbolic"
4940 /*@
4941    MatICCFactorSymbolic - Performs symbolic incomplete
4942    Cholesky factorization for a symmetric matrix.  Use
4943    MatCholeskyFactorNumeric() to complete the factorization.
4944 
4945    Collective on Mat
4946 
4947    Input Parameters:
4948 +  mat - the matrix
4949 .  perm - row and column permutation
4950 -  info - structure containing
4951 $      levels - number of levels of fill.
4952 $      expected fill - as ratio of original fill.
4953 
4954    Output Parameter:
4955 .  fact - the factored matrix
4956 
4957    Notes:
4958    Most users should employ the KSP interface for linear solvers
4959    instead of working directly with matrix algebra routines such as this.
4960    See, e.g., KSPCreate().
4961 
4962    Level: developer
4963 
4964   Concepts: matrices^symbolic incomplete Cholesky factorization
4965   Concepts: matrices^factorization
4966   Concepts: Cholsky^symbolic factorization
4967 
4968 .seealso: MatCholeskyFactorNumeric(), MatCholeskyFactor(), MatFactorInfo
4969 @*/
4970 PetscErrorCode PETSCMAT_DLLEXPORT MatICCFactorSymbolic(Mat mat,IS perm,MatFactorInfo *info,Mat *fact)
4971 {
4972   PetscErrorCode ierr;
4973 
4974   PetscFunctionBegin;
4975   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
4976   PetscValidType(mat,1);
4977   PetscValidHeaderSpecific(perm,IS_COOKIE,2);
4978   PetscValidPointer(info,3);
4979   PetscValidPointer(fact,4);
4980   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4981   if (info->levels < 0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Levels negative %D",(PetscInt) info->levels);
4982   if (info->fill < 1.0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Expected fill less than 1.0 %G",info->fill);
4983   if (!mat->ops->iccfactorsymbolic) SETERRQ1(PETSC_ERR_SUP,"Matrix type %s  symbolic ICC",((PetscObject)mat)->type_name);
4984   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4985   ierr = MatPreallocated(mat);CHKERRQ(ierr);
4986 
4987   ierr = PetscLogEventBegin(MAT_ICCFactorSymbolic,mat,perm,0,0);CHKERRQ(ierr);
4988   ierr = (*mat->ops->iccfactorsymbolic)(mat,perm,info,fact);CHKERRQ(ierr);
4989   ierr = PetscLogEventEnd(MAT_ICCFactorSymbolic,mat,perm,0,0);CHKERRQ(ierr);
4990   PetscFunctionReturn(0);
4991 }
4992 
4993 #undef __FUNCT__
4994 #define __FUNCT__ "MatGetArray"
4995 /*@C
4996    MatGetArray - Returns a pointer to the element values in the matrix.
4997    The result of this routine is dependent on the underlying matrix data
4998    structure, and may not even work for certain matrix types.  You MUST
4999    call MatRestoreArray() when you no longer need to access the array.
5000 
5001    Not Collective
5002 
5003    Input Parameter:
5004 .  mat - the matrix
5005 
5006    Output Parameter:
5007 .  v - the location of the values
5008 
5009 
5010    Fortran Note:
5011    This routine is used differently from Fortran, e.g.,
5012 .vb
5013         Mat         mat
5014         PetscScalar mat_array(1)
5015         PetscOffset i_mat
5016         PetscErrorCode ierr
5017         call MatGetArray(mat,mat_array,i_mat,ierr)
5018 
5019   C  Access first local entry in matrix; note that array is
5020   C  treated as one dimensional
5021         value = mat_array(i_mat + 1)
5022 
5023         [... other code ...]
5024         call MatRestoreArray(mat,mat_array,i_mat,ierr)
5025 .ve
5026 
5027    See the Fortran chapter of the users manual and
5028    petsc/src/mat/examples/tests for details.
5029 
5030    Level: advanced
5031 
5032    Concepts: matrices^access array
5033 
5034 .seealso: MatRestoreArray(), MatGetArrayF90(), MatGetRowIJ()
5035 @*/
5036 PetscErrorCode PETSCMAT_DLLEXPORT MatGetArray(Mat mat,PetscScalar *v[])
5037 {
5038   PetscErrorCode ierr;
5039 
5040   PetscFunctionBegin;
5041   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5042   PetscValidType(mat,1);
5043   PetscValidPointer(v,2);
5044   if (!mat->ops->getarray) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
5045   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5046   ierr = (*mat->ops->getarray)(mat,v);CHKERRQ(ierr);
5047   CHKMEMQ;
5048   PetscFunctionReturn(0);
5049 }
5050 
5051 #undef __FUNCT__
5052 #define __FUNCT__ "MatRestoreArray"
5053 /*@C
5054    MatRestoreArray - Restores the matrix after MatGetArray() has been called.
5055 
5056    Not Collective
5057 
5058    Input Parameter:
5059 +  mat - the matrix
5060 -  v - the location of the values
5061 
5062    Fortran Note:
5063    This routine is used differently from Fortran, e.g.,
5064 .vb
5065         Mat         mat
5066         PetscScalar mat_array(1)
5067         PetscOffset i_mat
5068         PetscErrorCode ierr
5069         call MatGetArray(mat,mat_array,i_mat,ierr)
5070 
5071   C  Access first local entry in matrix; note that array is
5072   C  treated as one dimensional
5073         value = mat_array(i_mat + 1)
5074 
5075         [... other code ...]
5076         call MatRestoreArray(mat,mat_array,i_mat,ierr)
5077 .ve
5078 
5079    See the Fortran chapter of the users manual and
5080    petsc/src/mat/examples/tests for details
5081 
5082    Level: advanced
5083 
5084 .seealso: MatGetArray(), MatRestoreArrayF90()
5085 @*/
5086 PetscErrorCode PETSCMAT_DLLEXPORT MatRestoreArray(Mat mat,PetscScalar *v[])
5087 {
5088   PetscErrorCode ierr;
5089 
5090   PetscFunctionBegin;
5091   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5092   PetscValidType(mat,1);
5093   PetscValidPointer(v,2);
5094 #if defined(PETSC_USE_DEBUG)
5095   CHKMEMQ;
5096 #endif
5097   if (!mat->ops->restorearray) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
5098   ierr = (*mat->ops->restorearray)(mat,v);CHKERRQ(ierr);
5099   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
5100   PetscFunctionReturn(0);
5101 }
5102 
5103 #undef __FUNCT__
5104 #define __FUNCT__ "MatGetSubMatrices"
5105 /*@C
5106    MatGetSubMatrices - Extracts several submatrices from a matrix. If submat
5107    points to an array of valid matrices, they may be reused to store the new
5108    submatrices.
5109 
5110    Collective on Mat
5111 
5112    Input Parameters:
5113 +  mat - the matrix
5114 .  n   - the number of submatrixes to be extracted (on this processor, may be zero)
5115 .  irow, icol - index sets of rows and columns to extract
5116 -  scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
5117 
5118    Output Parameter:
5119 .  submat - the array of submatrices
5120 
5121    Notes:
5122    MatGetSubMatrices() can extract only sequential submatrices
5123    (from both sequential and parallel matrices). Use MatGetSubMatrix()
5124    to extract a parallel submatrix.
5125 
5126    When extracting submatrices from a parallel matrix, each processor can
5127    form a different submatrix by setting the rows and columns of its
5128    individual index sets according to the local submatrix desired.
5129 
5130    When finished using the submatrices, the user should destroy
5131    them with MatDestroyMatrices().
5132 
5133    MAT_REUSE_MATRIX can only be used when the nonzero structure of the
5134    original matrix has not changed from that last call to MatGetSubMatrices().
5135 
5136    This routine creates the matrices in submat; you should NOT create them before
5137    calling it. It also allocates the array of matrix pointers submat.
5138 
5139    For BAIJ matrices the index sets must respect the block structure, that is if they
5140    request one row/column in a block, they must request all rows/columns that are in
5141    that block. For example, if the block size is 2 you cannot request just row 0 and
5142    column 0.
5143 
5144    Fortran Note:
5145    The Fortran interface is slightly different from that given below; it
5146    requires one to pass in  as submat a Mat (integer) array of size at least m.
5147 
5148    Level: advanced
5149 
5150    Concepts: matrices^accessing submatrices
5151    Concepts: submatrices
5152 
5153 .seealso: MatDestroyMatrices(), MatGetSubMatrix(), MatGetRow(), MatGetDiagonal()
5154 @*/
5155 PetscErrorCode PETSCMAT_DLLEXPORT MatGetSubMatrices(Mat mat,PetscInt n,const IS irow[],const IS icol[],MatReuse scall,Mat *submat[])
5156 {
5157   PetscErrorCode ierr;
5158   PetscInt        i;
5159   PetscTruth      eq;
5160 
5161   PetscFunctionBegin;
5162   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5163   PetscValidType(mat,1);
5164   if (n) {
5165     PetscValidPointer(irow,3);
5166     PetscValidHeaderSpecific(*irow,IS_COOKIE,3);
5167     PetscValidPointer(icol,4);
5168     PetscValidHeaderSpecific(*icol,IS_COOKIE,4);
5169   }
5170   PetscValidPointer(submat,6);
5171   if (n && scall == MAT_REUSE_MATRIX) {
5172     PetscValidPointer(*submat,6);
5173     PetscValidHeaderSpecific(**submat,MAT_COOKIE,6);
5174   }
5175   if (!mat->ops->getsubmatrices) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
5176   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
5177   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
5178   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5179 
5180   ierr = PetscLogEventBegin(MAT_GetSubMatrices,mat,0,0,0);CHKERRQ(ierr);
5181   ierr = (*mat->ops->getsubmatrices)(mat,n,irow,icol,scall,submat);CHKERRQ(ierr);
5182   ierr = PetscLogEventEnd(MAT_GetSubMatrices,mat,0,0,0);CHKERRQ(ierr);
5183   for (i=0; i<n; i++) {
5184     if (mat->symmetric || mat->structurally_symmetric || mat->hermitian) {
5185       ierr = ISEqual(irow[i],icol[i],&eq);CHKERRQ(ierr);
5186       if (eq) {
5187 	if (mat->symmetric){
5188 	  ierr = MatSetOption((*submat)[i],MAT_SYMMETRIC,PETSC_TRUE);CHKERRQ(ierr);
5189 	} else if (mat->hermitian) {
5190 	  ierr = MatSetOption((*submat)[i],MAT_HERMITIAN,PETSC_TRUE);CHKERRQ(ierr);
5191 	} else if (mat->structurally_symmetric) {
5192 	  ierr = MatSetOption((*submat)[i],MAT_STRUCTURALLY_SYMMETRIC,PETSC_TRUE);CHKERRQ(ierr);
5193 	}
5194       }
5195     }
5196   }
5197   PetscFunctionReturn(0);
5198 }
5199 
5200 #undef __FUNCT__
5201 #define __FUNCT__ "MatDestroyMatrices"
5202 /*@C
5203    MatDestroyMatrices - Destroys a set of matrices obtained with MatGetSubMatrices().
5204 
5205    Collective on Mat
5206 
5207    Input Parameters:
5208 +  n - the number of local matrices
5209 -  mat - the matrices (note that this is a pointer to the array of matrices, just to match the calling
5210                        sequence of MatGetSubMatrices())
5211 
5212    Level: advanced
5213 
5214     Notes: Frees not only the matrices, but also the array that contains the matrices
5215 
5216 .seealso: MatGetSubMatrices()
5217 @*/
5218 PetscErrorCode PETSCMAT_DLLEXPORT MatDestroyMatrices(PetscInt n,Mat *mat[])
5219 {
5220   PetscErrorCode ierr;
5221   PetscInt       i;
5222 
5223   PetscFunctionBegin;
5224   if (n < 0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Trying to destroy negative number of matrices %D",n);
5225   PetscValidPointer(mat,2);
5226   for (i=0; i<n; i++) {
5227     ierr = MatDestroy((*mat)[i]);CHKERRQ(ierr);
5228   }
5229   /* memory is allocated even if n = 0 */
5230   ierr = PetscFree(*mat);CHKERRQ(ierr);
5231   PetscFunctionReturn(0);
5232 }
5233 
5234 #undef __FUNCT__
5235 #define __FUNCT__ "MatGetSeqNonzeroStructure"
5236 /*@C
5237    MatGetSeqNonzeroStructure - Extracts the sequential nonzero structure from a matrix.
5238 
5239    Collective on Mat
5240 
5241    Input Parameters:
5242 .  mat - the matrix
5243 
5244    Output Parameter:
5245 .  matstruct - the sequential matrix with the nonzero structure of mat
5246 
5247   Level: intermediate
5248 
5249 .seealso: MatDestroySeqNonzeroStructure(), MatGetSubMatrices(), MatDestroyMatrices()
5250 @*/
5251 PetscErrorCode PETSCMAT_DLLEXPORT MatGetSeqNonzeroStructure(Mat mat,Mat *matstruct[])
5252 {
5253   PetscErrorCode ierr;
5254 
5255   PetscFunctionBegin;
5256   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5257   PetscValidPointer(matstruct,2);
5258 
5259   PetscValidType(mat,1);
5260   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
5261   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5262 
5263   ierr = PetscLogEventBegin(MAT_GetSeqNonzeroStructure,mat,0,0,0);CHKERRQ(ierr);
5264   ierr = (*mat->ops->getseqnonzerostructure)(mat,matstruct);CHKERRQ(ierr);
5265   ierr = PetscLogEventEnd(MAT_GetSeqNonzeroStructure,mat,0,0,0);CHKERRQ(ierr);
5266   PetscFunctionReturn(0);
5267 }
5268 
5269 #undef __FUNCT__
5270 #define __FUNCT__ "MatDestroySeqNonzeroStructure"
5271 /*@C
5272    MatDestroySeqNonzeroStructure - Destroys matrix obtained with MatGetSeqNonzeroStructure().
5273 
5274    Collective on Mat
5275 
5276    Input Parameters:
5277 .  mat - the matrix (note that this is a pointer to the array of matrices, just to match the calling
5278                        sequence of MatGetSequentialNonzeroStructure())
5279 
5280    Level: advanced
5281 
5282     Notes: Frees not only the matrices, but also the array that contains the matrices
5283 
5284 .seealso: MatGetSeqNonzeroStructure()
5285 @*/
5286 PetscErrorCode PETSCMAT_DLLEXPORT MatDestroySeqNonzeroStructure(Mat *mat[])
5287 {
5288   PetscErrorCode ierr;
5289 
5290   PetscFunctionBegin;
5291   PetscValidPointer(mat,1);
5292   ierr = MatDestroyMatrices(1,mat);CHKERRQ(ierr);
5293   PetscFunctionReturn(0);
5294 }
5295 
5296 #undef __FUNCT__
5297 #define __FUNCT__ "MatIncreaseOverlap"
5298 /*@
5299    MatIncreaseOverlap - Given a set of submatrices indicated by index sets,
5300    replaces the index sets by larger ones that represent submatrices with
5301    additional overlap.
5302 
5303    Collective on Mat
5304 
5305    Input Parameters:
5306 +  mat - the matrix
5307 .  n   - the number of index sets
5308 .  is  - the array of index sets (these index sets will changed during the call)
5309 -  ov  - the additional overlap requested
5310 
5311    Level: developer
5312 
5313    Concepts: overlap
5314    Concepts: ASM^computing overlap
5315 
5316 .seealso: MatGetSubMatrices()
5317 @*/
5318 PetscErrorCode PETSCMAT_DLLEXPORT MatIncreaseOverlap(Mat mat,PetscInt n,IS is[],PetscInt ov)
5319 {
5320   PetscErrorCode ierr;
5321 
5322   PetscFunctionBegin;
5323   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5324   PetscValidType(mat,1);
5325   if (n < 0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Must have one or more domains, you have %D",n);
5326   if (n) {
5327     PetscValidPointer(is,3);
5328     PetscValidHeaderSpecific(*is,IS_COOKIE,3);
5329   }
5330   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
5331   if (mat->factor)     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
5332   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5333 
5334   if (!ov) PetscFunctionReturn(0);
5335   if (!mat->ops->increaseoverlap) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
5336   ierr = PetscLogEventBegin(MAT_IncreaseOverlap,mat,0,0,0);CHKERRQ(ierr);
5337   ierr = (*mat->ops->increaseoverlap)(mat,n,is,ov);CHKERRQ(ierr);
5338   ierr = PetscLogEventEnd(MAT_IncreaseOverlap,mat,0,0,0);CHKERRQ(ierr);
5339   PetscFunctionReturn(0);
5340 }
5341 
5342 #undef __FUNCT__
5343 #define __FUNCT__ "MatGetBlockSize"
5344 /*@
5345    MatGetBlockSize - Returns the matrix block size; useful especially for the
5346    block row and block diagonal formats.
5347 
5348    Not Collective
5349 
5350    Input Parameter:
5351 .  mat - the matrix
5352 
5353    Output Parameter:
5354 .  bs - block size
5355 
5356    Notes:
5357    Block row formats are MATSEQBAIJ, MATMPIBAIJ, MATSEQSBAIJ, MATMPISBAIJ
5358 
5359    Level: intermediate
5360 
5361    Concepts: matrices^block size
5362 
5363 .seealso: MatCreateSeqBAIJ(), MatCreateMPIBAIJ()
5364 @*/
5365 PetscErrorCode PETSCMAT_DLLEXPORT MatGetBlockSize(Mat mat,PetscInt *bs)
5366 {
5367   PetscErrorCode ierr;
5368 
5369   PetscFunctionBegin;
5370   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5371   PetscValidType(mat,1);
5372   PetscValidIntPointer(bs,2);
5373   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5374   *bs = mat->rmap.bs;
5375   PetscFunctionReturn(0);
5376 }
5377 
5378 #undef __FUNCT__
5379 #define __FUNCT__ "MatSetBlockSize"
5380 /*@
5381    MatSetBlockSize - Sets the matrix block size; for many matrix types you
5382      cannot use this and MUST set the blocksize when you preallocate the matrix
5383 
5384    Collective on Mat
5385 
5386    Input Parameters:
5387 +  mat - the matrix
5388 -  bs - block size
5389 
5390    Notes:
5391      Only works for shell and AIJ matrices
5392 
5393    Level: intermediate
5394 
5395    Concepts: matrices^block size
5396 
5397 .seealso: MatCreateSeqBAIJ(), MatCreateMPIBAIJ(), MatGetBlockSize()
5398 @*/
5399 PetscErrorCode PETSCMAT_DLLEXPORT MatSetBlockSize(Mat mat,PetscInt bs)
5400 {
5401   PetscErrorCode ierr;
5402 
5403   PetscFunctionBegin;
5404   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5405   PetscValidType(mat,1);
5406   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5407   if (mat->ops->setblocksize) {
5408     mat->rmap.bs = bs;
5409     ierr = (*mat->ops->setblocksize)(mat,bs);CHKERRQ(ierr);
5410   } else {
5411     SETERRQ1(PETSC_ERR_ARG_INCOMP,"Cannot set the blocksize for matrix type %s",((PetscObject)mat)->type_name);
5412   }
5413   PetscFunctionReturn(0);
5414 }
5415 
5416 #undef __FUNCT__
5417 #define __FUNCT__ "MatGetRowIJ"
5418 /*@C
5419     MatGetRowIJ - Returns the compressed row storage i and j indices for sequential matrices.
5420 
5421    Collective on Mat
5422 
5423     Input Parameters:
5424 +   mat - the matrix
5425 .   shift -  0 or 1 indicating we want the indices starting at 0 or 1
5426 .   symmetric - PETSC_TRUE or PETSC_FALSE indicating the matrix data structure should be
5427                 symmetrized
5428 -   blockcompressed - PETSC_TRUE or PETSC_FALSE  indicating if the nonzero structure of the
5429                  blockcompressed matrix is desired or not [inode, baij have blockcompressed
5430                  nonzero structure which is different than the full nonzero structure]
5431 
5432     Output Parameters:
5433 +   n - number of rows in the (possibly compressed) matrix
5434 .   ia - the row pointers [of length n+1]
5435 .   ja - the column indices
5436 -   done - indicates if the routine actually worked and returned appropriate ia[] and ja[] arrays; callers
5437            are responsible for handling the case when done == PETSC_FALSE and ia and ja are not set
5438 
5439     Level: developer
5440 
5441     Notes: You CANNOT change any of the ia[] or ja[] values.
5442 
5443            Use MatRestoreRowIJ() when you are finished accessing the ia[] and ja[] values
5444 
5445     Fortran Node
5446 
5447            In Fortran use
5448 $           PetscInt ia(1), ja(1)
5449 $           PetscOffset iia, jja
5450 $      call MatGetRowIJ(mat,shift,symmetric,blockcompressed,n,ia,iia,ja,jja,done,ierr)
5451 
5452        Acess the ith and jth entries via ia(iia + i) and ja(jja + j)
5453 
5454 .seealso: MatGetColumnIJ(), MatRestoreRowIJ(), MatGetArray()
5455 @*/
5456 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRowIJ(Mat mat,PetscInt shift,PetscTruth symmetric,PetscTruth blockcompressed,PetscInt *n,PetscInt *ia[],PetscInt* ja[],PetscTruth *done)
5457 {
5458   PetscErrorCode ierr;
5459 
5460   PetscFunctionBegin;
5461   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5462   PetscValidType(mat,1);
5463   PetscValidIntPointer(n,4);
5464   if (ia) PetscValidIntPointer(ia,5);
5465   if (ja) PetscValidIntPointer(ja,6);
5466   PetscValidIntPointer(done,7);
5467   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5468   if (!mat->ops->getrowij) *done = PETSC_FALSE;
5469   else {
5470     *done = PETSC_TRUE;
5471     ierr = PetscLogEventBegin(MAT_GetRowIJ,mat,0,0,0);CHKERRQ(ierr);
5472     ierr  = (*mat->ops->getrowij)(mat,shift,symmetric,blockcompressed,n,ia,ja,done);CHKERRQ(ierr);
5473     ierr = PetscLogEventEnd(MAT_GetRowIJ,mat,0,0,0);CHKERRQ(ierr);
5474   }
5475   PetscFunctionReturn(0);
5476 }
5477 
5478 #undef __FUNCT__
5479 #define __FUNCT__ "MatGetColumnIJ"
5480 /*@C
5481     MatGetColumnIJ - Returns the compressed column storage i and j indices for sequential matrices.
5482 
5483     Collective on Mat
5484 
5485     Input Parameters:
5486 +   mat - the matrix
5487 .   shift - 1 or zero indicating we want the indices starting at 0 or 1
5488 .   symmetric - PETSC_TRUE or PETSC_FALSE indicating the matrix data structure should be
5489                 symmetrized
5490 -   blockcompressed - PETSC_TRUE or PETSC_FALSE  indicating if the nonzero structure of the
5491                  blockcompressed matrix is desired or not [inode, baij have blockcompressed
5492                  nonzero structure which is different than the full nonzero structure]
5493 
5494     Output Parameters:
5495 +   n - number of columns in the (possibly compressed) matrix
5496 .   ia - the column pointers
5497 .   ja - the row indices
5498 -   done - PETSC_TRUE or PETSC_FALSE, indicating whether the values have been returned
5499 
5500     Level: developer
5501 
5502 .seealso: MatGetRowIJ(), MatRestoreColumnIJ()
5503 @*/
5504 PetscErrorCode PETSCMAT_DLLEXPORT MatGetColumnIJ(Mat mat,PetscInt shift,PetscTruth symmetric,PetscTruth blockcompressed,PetscInt *n,PetscInt *ia[],PetscInt* ja[],PetscTruth *done)
5505 {
5506   PetscErrorCode ierr;
5507 
5508   PetscFunctionBegin;
5509   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5510   PetscValidType(mat,1);
5511   PetscValidIntPointer(n,4);
5512   if (ia) PetscValidIntPointer(ia,5);
5513   if (ja) PetscValidIntPointer(ja,6);
5514   PetscValidIntPointer(done,7);
5515   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5516   if (!mat->ops->getcolumnij) *done = PETSC_FALSE;
5517   else {
5518     *done = PETSC_TRUE;
5519     ierr  = (*mat->ops->getcolumnij)(mat,shift,symmetric,blockcompressed,n,ia,ja,done);CHKERRQ(ierr);
5520   }
5521   PetscFunctionReturn(0);
5522 }
5523 
5524 #undef __FUNCT__
5525 #define __FUNCT__ "MatRestoreRowIJ"
5526 /*@C
5527     MatRestoreRowIJ - Call after you are completed with the ia,ja indices obtained with
5528     MatGetRowIJ().
5529 
5530     Collective on Mat
5531 
5532     Input Parameters:
5533 +   mat - the matrix
5534 .   shift - 1 or zero indicating we want the indices starting at 0 or 1
5535 .   symmetric - PETSC_TRUE or PETSC_FALSE indicating the matrix data structure should be
5536                 symmetrized
5537 -   blockcompressed - PETSC_TRUE or PETSC_FALSE  indicating if the nonzero structure of the
5538                  blockcompressed matrix is desired or not [inode, baij have blockcompressed
5539                  nonzero structure which is different than the full nonzero structure]
5540 
5541     Output Parameters:
5542 +   n - size of (possibly compressed) matrix
5543 .   ia - the row pointers
5544 .   ja - the column indices
5545 -   done - PETSC_TRUE or PETSC_FALSE indicated that the values have been returned
5546 
5547     Level: developer
5548 
5549 .seealso: MatGetRowIJ(), MatRestoreColumnIJ()
5550 @*/
5551 PetscErrorCode PETSCMAT_DLLEXPORT MatRestoreRowIJ(Mat mat,PetscInt shift,PetscTruth symmetric,PetscTruth blockcompressed,PetscInt *n,PetscInt *ia[],PetscInt* ja[],PetscTruth *done)
5552 {
5553   PetscErrorCode ierr;
5554 
5555   PetscFunctionBegin;
5556   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5557   PetscValidType(mat,1);
5558   if (ia) PetscValidIntPointer(ia,5);
5559   if (ja) PetscValidIntPointer(ja,6);
5560   PetscValidIntPointer(done,7);
5561   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5562 
5563   if (!mat->ops->restorerowij) *done = PETSC_FALSE;
5564   else {
5565     *done = PETSC_TRUE;
5566     ierr  = (*mat->ops->restorerowij)(mat,shift,symmetric,blockcompressed,n,ia,ja,done);CHKERRQ(ierr);
5567   }
5568   PetscFunctionReturn(0);
5569 }
5570 
5571 #undef __FUNCT__
5572 #define __FUNCT__ "MatRestoreColumnIJ"
5573 /*@C
5574     MatRestoreColumnIJ - Call after you are completed with the ia,ja indices obtained with
5575     MatGetColumnIJ().
5576 
5577     Collective on Mat
5578 
5579     Input Parameters:
5580 +   mat - the matrix
5581 .   shift - 1 or zero indicating we want the indices starting at 0 or 1
5582 -   symmetric - PETSC_TRUE or PETSC_FALSE indicating the matrix data structure should be
5583                 symmetrized
5584 -   blockcompressed - PETSC_TRUE or PETSC_FALSE  indicating if the nonzero structure of the
5585                  blockcompressed matrix is desired or not [inode, baij have blockcompressed
5586                  nonzero structure which is different than the full nonzero structure]
5587 
5588     Output Parameters:
5589 +   n - size of (possibly compressed) matrix
5590 .   ia - the column pointers
5591 .   ja - the row indices
5592 -   done - PETSC_TRUE or PETSC_FALSE indicated that the values have been returned
5593 
5594     Level: developer
5595 
5596 .seealso: MatGetColumnIJ(), MatRestoreRowIJ()
5597 @*/
5598 PetscErrorCode PETSCMAT_DLLEXPORT MatRestoreColumnIJ(Mat mat,PetscInt shift,PetscTruth symmetric,PetscTruth blockcompressed,PetscInt *n,PetscInt *ia[],PetscInt* ja[],PetscTruth *done)
5599 {
5600   PetscErrorCode ierr;
5601 
5602   PetscFunctionBegin;
5603   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5604   PetscValidType(mat,1);
5605   if (ia) PetscValidIntPointer(ia,5);
5606   if (ja) PetscValidIntPointer(ja,6);
5607   PetscValidIntPointer(done,7);
5608   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5609 
5610   if (!mat->ops->restorecolumnij) *done = PETSC_FALSE;
5611   else {
5612     *done = PETSC_TRUE;
5613     ierr  = (*mat->ops->restorecolumnij)(mat,shift,symmetric,blockcompressed,n,ia,ja,done);CHKERRQ(ierr);
5614   }
5615   PetscFunctionReturn(0);
5616 }
5617 
5618 #undef __FUNCT__
5619 #define __FUNCT__ "MatColoringPatch"
5620 /*@C
5621     MatColoringPatch -Used inside matrix coloring routines that
5622     use MatGetRowIJ() and/or MatGetColumnIJ().
5623 
5624     Collective on Mat
5625 
5626     Input Parameters:
5627 +   mat - the matrix
5628 .   ncolors - max color value
5629 .   n   - number of entries in colorarray
5630 -   colorarray - array indicating color for each column
5631 
5632     Output Parameters:
5633 .   iscoloring - coloring generated using colorarray information
5634 
5635     Level: developer
5636 
5637 .seealso: MatGetRowIJ(), MatGetColumnIJ()
5638 
5639 @*/
5640 PetscErrorCode PETSCMAT_DLLEXPORT MatColoringPatch(Mat mat,PetscInt ncolors,PetscInt n,ISColoringValue colorarray[],ISColoring *iscoloring)
5641 {
5642   PetscErrorCode ierr;
5643 
5644   PetscFunctionBegin;
5645   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5646   PetscValidType(mat,1);
5647   PetscValidIntPointer(colorarray,4);
5648   PetscValidPointer(iscoloring,5);
5649   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5650 
5651   if (!mat->ops->coloringpatch){
5652     ierr = ISColoringCreate(((PetscObject)mat)->comm,ncolors,n,colorarray,iscoloring);CHKERRQ(ierr);
5653   } else {
5654     ierr = (*mat->ops->coloringpatch)(mat,ncolors,n,colorarray,iscoloring);CHKERRQ(ierr);
5655   }
5656   PetscFunctionReturn(0);
5657 }
5658 
5659 
5660 #undef __FUNCT__
5661 #define __FUNCT__ "MatSetUnfactored"
5662 /*@
5663    MatSetUnfactored - Resets a factored matrix to be treated as unfactored.
5664 
5665    Collective on Mat
5666 
5667    Input Parameter:
5668 .  mat - the factored matrix to be reset
5669 
5670    Notes:
5671    This routine should be used only with factored matrices formed by in-place
5672    factorization via ILU(0) (or by in-place LU factorization for the MATSEQDENSE
5673    format).  This option can save memory, for example, when solving nonlinear
5674    systems with a matrix-free Newton-Krylov method and a matrix-based, in-place
5675    ILU(0) preconditioner.
5676 
5677    Note that one can specify in-place ILU(0) factorization by calling
5678 .vb
5679      PCType(pc,PCILU);
5680      PCFactorSeUseInPlace(pc);
5681 .ve
5682    or by using the options -pc_type ilu -pc_factor_in_place
5683 
5684    In-place factorization ILU(0) can also be used as a local
5685    solver for the blocks within the block Jacobi or additive Schwarz
5686    methods (runtime option: -sub_pc_factor_in_place).  See the discussion
5687    of these preconditioners in the users manual for details on setting
5688    local solver options.
5689 
5690    Most users should employ the simplified KSP interface for linear solvers
5691    instead of working directly with matrix algebra routines such as this.
5692    See, e.g., KSPCreate().
5693 
5694    Level: developer
5695 
5696 .seealso: PCFactorSetUseInPlace()
5697 
5698    Concepts: matrices^unfactored
5699 
5700 @*/
5701 PetscErrorCode PETSCMAT_DLLEXPORT MatSetUnfactored(Mat mat)
5702 {
5703   PetscErrorCode ierr;
5704 
5705   PetscFunctionBegin;
5706   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5707   PetscValidType(mat,1);
5708   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5709   mat->factor = 0;
5710   if (!mat->ops->setunfactored) PetscFunctionReturn(0);
5711   ierr = (*mat->ops->setunfactored)(mat);CHKERRQ(ierr);
5712   PetscFunctionReturn(0);
5713 }
5714 
5715 /*MC
5716     MatGetArrayF90 - Accesses a matrix array from Fortran90.
5717 
5718     Synopsis:
5719     MatGetArrayF90(Mat x,{Scalar, pointer :: xx_v(:)},integer ierr)
5720 
5721     Not collective
5722 
5723     Input Parameter:
5724 .   x - matrix
5725 
5726     Output Parameters:
5727 +   xx_v - the Fortran90 pointer to the array
5728 -   ierr - error code
5729 
5730     Example of Usage:
5731 .vb
5732       PetscScalar, pointer xx_v(:)
5733       ....
5734       call MatGetArrayF90(x,xx_v,ierr)
5735       a = xx_v(3)
5736       call MatRestoreArrayF90(x,xx_v,ierr)
5737 .ve
5738 
5739     Notes:
5740     Not yet supported for all F90 compilers
5741 
5742     Level: advanced
5743 
5744 .seealso:  MatRestoreArrayF90(), MatGetArray(), MatRestoreArray()
5745 
5746     Concepts: matrices^accessing array
5747 
5748 M*/
5749 
5750 /*MC
5751     MatRestoreArrayF90 - Restores a matrix array that has been
5752     accessed with MatGetArrayF90().
5753 
5754     Synopsis:
5755     MatRestoreArrayF90(Mat x,{Scalar, pointer :: xx_v(:)},integer ierr)
5756 
5757     Not collective
5758 
5759     Input Parameters:
5760 +   x - matrix
5761 -   xx_v - the Fortran90 pointer to the array
5762 
5763     Output Parameter:
5764 .   ierr - error code
5765 
5766     Example of Usage:
5767 .vb
5768        PetscScalar, pointer xx_v(:)
5769        ....
5770        call MatGetArrayF90(x,xx_v,ierr)
5771        a = xx_v(3)
5772        call MatRestoreArrayF90(x,xx_v,ierr)
5773 .ve
5774 
5775     Notes:
5776     Not yet supported for all F90 compilers
5777 
5778     Level: advanced
5779 
5780 .seealso:  MatGetArrayF90(), MatGetArray(), MatRestoreArray()
5781 
5782 M*/
5783 
5784 
5785 #undef __FUNCT__
5786 #define __FUNCT__ "MatGetSubMatrix"
5787 /*@
5788     MatGetSubMatrix - Gets a single submatrix on the same number of processors
5789                       as the original matrix.
5790 
5791     Collective on Mat
5792 
5793     Input Parameters:
5794 +   mat - the original matrix
5795 .   isrow - rows this processor should obtain
5796 .   iscol - columns for all processors you wish to keep
5797 .   csize - number of columns "local" to this processor (does nothing for sequential
5798             matrices). This should match the result from VecGetLocalSize(x,...) if you
5799             plan to use the matrix in a A*x; alternatively, you can use PETSC_DECIDE
5800 -   cll - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
5801 
5802     Output Parameter:
5803 .   newmat - the new submatrix, of the same type as the old
5804 
5805     Level: advanced
5806 
5807     Notes: the iscol argument MUST be the same on each processor. You might be
5808     able to create the iscol argument with ISAllGather(). The rows is isrow will be
5809     sorted into the same order as the original matrix.
5810 
5811       The first time this is called you should use a cll of MAT_INITIAL_MATRIX,
5812    the MatGetSubMatrix() routine will create the newmat for you. Any additional calls
5813    to this routine with a mat of the same nonzero structure and with a call of MAT_REUSE_MATRIX
5814    will reuse the matrix generated the first time.  You should call MatDestroy() on newmat when
5815    you are finished using it.
5816 
5817     Concepts: matrices^submatrices
5818 
5819 .seealso: MatGetSubMatrices(), ISAllGather()
5820 @*/
5821 PetscErrorCode PETSCMAT_DLLEXPORT MatGetSubMatrix(Mat mat,IS isrow,IS iscol,PetscInt csize,MatReuse cll,Mat *newmat)
5822 {
5823   PetscErrorCode ierr;
5824   PetscMPIInt    size;
5825   Mat            *local;
5826 
5827   PetscFunctionBegin;
5828   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5829   PetscValidHeaderSpecific(isrow,IS_COOKIE,2);
5830   PetscValidHeaderSpecific(iscol,IS_COOKIE,3);
5831   PetscValidPointer(newmat,6);
5832   if (cll == MAT_REUSE_MATRIX) PetscValidHeaderSpecific(*newmat,MAT_COOKIE,6);
5833   PetscValidType(mat,1);
5834   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
5835   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5836   ierr = MPI_Comm_size(((PetscObject)mat)->comm,&size);CHKERRQ(ierr);
5837 
5838   /* if original matrix is on just one processor then use submatrix generated */
5839   if (!mat->ops->getsubmatrix && size == 1 && cll == MAT_REUSE_MATRIX) {
5840     ierr = MatGetSubMatrices(mat,1,&isrow,&iscol,MAT_REUSE_MATRIX,&newmat);CHKERRQ(ierr);
5841     PetscFunctionReturn(0);
5842   } else if (!mat->ops->getsubmatrix && size == 1) {
5843     ierr    = MatGetSubMatrices(mat,1,&isrow,&iscol,MAT_INITIAL_MATRIX,&local);CHKERRQ(ierr);
5844     *newmat = *local;
5845     ierr    = PetscFree(local);CHKERRQ(ierr);
5846     PetscFunctionReturn(0);
5847   }
5848 
5849   if (!mat->ops->getsubmatrix) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
5850   ierr = (*mat->ops->getsubmatrix)(mat,isrow,iscol,csize,cll,newmat);CHKERRQ(ierr);
5851   ierr = PetscObjectStateIncrease((PetscObject)*newmat);CHKERRQ(ierr);
5852   PetscFunctionReturn(0);
5853 }
5854 
5855 #undef __FUNCT__
5856 #define __FUNCT__ "MatGetSubMatrixRaw"
5857 /*@
5858     MatGetSubMatrixRaw - Gets a single submatrix on the same number of processors
5859                          as the original matrix.
5860 
5861     Collective on Mat
5862 
5863     Input Parameters:
5864 +   mat - the original matrix
5865 .   nrows - the number of rows this processor should obtain
5866 .   rows - rows this processor should obtain
5867 .   ncols - the number of columns for all processors you wish to keep
5868 .   cols - columns for all processors you wish to keep
5869 .   csize - number of columns "local" to this processor (does nothing for sequential
5870             matrices). This should match the result from VecGetLocalSize(x,...) if you
5871             plan to use the matrix in a A*x; alternatively, you can use PETSC_DECIDE
5872 -   cll - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
5873 
5874     Output Parameter:
5875 .   newmat - the new submatrix, of the same type as the old
5876 
5877     Level: advanced
5878 
5879     Notes: the iscol argument MUST be the same on each processor. You might be
5880     able to create the iscol argument with ISAllGather().
5881 
5882       The first time this is called you should use a cll of MAT_INITIAL_MATRIX,
5883    the MatGetSubMatrix() routine will create the newmat for you. Any additional calls
5884    to this routine with a mat of the same nonzero structure and with a cll of MAT_REUSE_MATRIX
5885    will reuse the matrix generated the first time.
5886 
5887     Concepts: matrices^submatrices
5888 
5889 .seealso: MatGetSubMatrices(), ISAllGather()
5890 @*/
5891 PetscErrorCode PETSCMAT_DLLEXPORT MatGetSubMatrixRaw(Mat mat,PetscInt nrows,const PetscInt rows[],PetscInt ncols,const PetscInt cols[],PetscInt csize,MatReuse cll,Mat *newmat)
5892 {
5893   IS             isrow, iscol;
5894   PetscErrorCode ierr;
5895 
5896   PetscFunctionBegin;
5897   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5898   PetscValidIntPointer(rows,2);
5899   PetscValidIntPointer(cols,3);
5900   PetscValidPointer(newmat,6);
5901   if (cll == MAT_REUSE_MATRIX) PetscValidHeaderSpecific(*newmat,MAT_COOKIE,6);
5902   PetscValidType(mat,1);
5903   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
5904   ierr = MatPreallocated(mat);CHKERRQ(ierr);
5905   ierr = ISCreateGeneralWithArray(PETSC_COMM_SELF, nrows, (PetscInt *) rows, &isrow);CHKERRQ(ierr);
5906   ierr = ISCreateGeneralWithArray(PETSC_COMM_SELF, ncols, (PetscInt *) cols, &iscol);CHKERRQ(ierr);
5907   ierr = MatGetSubMatrix(mat, isrow, iscol, csize, cll, newmat);CHKERRQ(ierr);
5908   ierr = ISDestroy(isrow);CHKERRQ(ierr);
5909   ierr = ISDestroy(iscol);CHKERRQ(ierr);
5910   PetscFunctionReturn(0);
5911 }
5912 
5913 #undef __FUNCT__
5914 #define __FUNCT__ "MatStashSetInitialSize"
5915 /*@
5916    MatStashSetInitialSize - sets the sizes of the matrix stash, that is
5917    used during the assembly process to store values that belong to
5918    other processors.
5919 
5920    Not Collective
5921 
5922    Input Parameters:
5923 +  mat   - the matrix
5924 .  size  - the initial size of the stash.
5925 -  bsize - the initial size of the block-stash(if used).
5926 
5927    Options Database Keys:
5928 +   -matstash_initial_size <size> or <size0,size1,...sizep-1>
5929 -   -matstash_block_initial_size <bsize>  or <bsize0,bsize1,...bsizep-1>
5930 
5931    Level: intermediate
5932 
5933    Notes:
5934      The block-stash is used for values set with MatSetValuesBlocked() while
5935      the stash is used for values set with MatSetValues()
5936 
5937      Run with the option -info and look for output of the form
5938      MatAssemblyBegin_MPIXXX:Stash has MM entries, uses nn mallocs.
5939      to determine the appropriate value, MM, to use for size and
5940      MatAssemblyBegin_MPIXXX:Block-Stash has BMM entries, uses nn mallocs.
5941      to determine the value, BMM to use for bsize
5942 
5943    Concepts: stash^setting matrix size
5944    Concepts: matrices^stash
5945 
5946 @*/
5947 PetscErrorCode PETSCMAT_DLLEXPORT MatStashSetInitialSize(Mat mat,PetscInt size, PetscInt bsize)
5948 {
5949   PetscErrorCode ierr;
5950 
5951   PetscFunctionBegin;
5952   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
5953   PetscValidType(mat,1);
5954   ierr = MatStashSetInitialSize_Private(&mat->stash,size);CHKERRQ(ierr);
5955   ierr = MatStashSetInitialSize_Private(&mat->bstash,bsize);CHKERRQ(ierr);
5956   PetscFunctionReturn(0);
5957 }
5958 
5959 #undef __FUNCT__
5960 #define __FUNCT__ "MatInterpolateAdd"
5961 /*@
5962    MatInterpolateAdd - w = y + A*x or A'*x depending on the shape of
5963      the matrix
5964 
5965    Collective on Mat
5966 
5967    Input Parameters:
5968 +  mat   - the matrix
5969 .  x,y - the vectors
5970 -  w - where the result is stored
5971 
5972    Level: intermediate
5973 
5974    Notes:
5975     w may be the same vector as y.
5976 
5977     This allows one to use either the restriction or interpolation (its transpose)
5978     matrix to do the interpolation
5979 
5980     Concepts: interpolation
5981 
5982 .seealso: MatMultAdd(), MatMultTransposeAdd(), MatRestrict()
5983 
5984 @*/
5985 PetscErrorCode PETSCMAT_DLLEXPORT MatInterpolateAdd(Mat A,Vec x,Vec y,Vec w)
5986 {
5987   PetscErrorCode ierr;
5988   PetscInt       M,N;
5989 
5990   PetscFunctionBegin;
5991   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
5992   PetscValidHeaderSpecific(x,VEC_COOKIE,2);
5993   PetscValidHeaderSpecific(y,VEC_COOKIE,3);
5994   PetscValidHeaderSpecific(w,VEC_COOKIE,4);
5995   PetscValidType(A,1);
5996   ierr = MatPreallocated(A);CHKERRQ(ierr);
5997   ierr = MatGetSize(A,&M,&N);CHKERRQ(ierr);
5998   if (N > M) {
5999     ierr = MatMultTransposeAdd(A,x,y,w);CHKERRQ(ierr);
6000   } else {
6001     ierr = MatMultAdd(A,x,y,w);CHKERRQ(ierr);
6002   }
6003   PetscFunctionReturn(0);
6004 }
6005 
6006 #undef __FUNCT__
6007 #define __FUNCT__ "MatInterpolate"
6008 /*@
6009    MatInterpolate - y = A*x or A'*x depending on the shape of
6010      the matrix
6011 
6012    Collective on Mat
6013 
6014    Input Parameters:
6015 +  mat   - the matrix
6016 -  x,y - the vectors
6017 
6018    Level: intermediate
6019 
6020    Notes:
6021     This allows one to use either the restriction or interpolation (its transpose)
6022     matrix to do the interpolation
6023 
6024    Concepts: matrices^interpolation
6025 
6026 .seealso: MatMultAdd(), MatMultTransposeAdd(), MatRestrict()
6027 
6028 @*/
6029 PetscErrorCode PETSCMAT_DLLEXPORT MatInterpolate(Mat A,Vec x,Vec y)
6030 {
6031   PetscErrorCode ierr;
6032   PetscInt       M,N;
6033 
6034   PetscFunctionBegin;
6035   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
6036   PetscValidHeaderSpecific(x,VEC_COOKIE,2);
6037   PetscValidHeaderSpecific(y,VEC_COOKIE,3);
6038   PetscValidType(A,1);
6039   ierr = MatPreallocated(A);CHKERRQ(ierr);
6040   ierr = MatGetSize(A,&M,&N);CHKERRQ(ierr);
6041   if (N > M) {
6042     ierr = MatMultTranspose(A,x,y);CHKERRQ(ierr);
6043   } else {
6044     ierr = MatMult(A,x,y);CHKERRQ(ierr);
6045   }
6046   PetscFunctionReturn(0);
6047 }
6048 
6049 #undef __FUNCT__
6050 #define __FUNCT__ "MatRestrict"
6051 /*@
6052    MatRestrict - y = A*x or A'*x
6053 
6054    Collective on Mat
6055 
6056    Input Parameters:
6057 +  mat   - the matrix
6058 -  x,y - the vectors
6059 
6060    Level: intermediate
6061 
6062    Notes:
6063     This allows one to use either the restriction or interpolation (its transpose)
6064     matrix to do the restriction
6065 
6066    Concepts: matrices^restriction
6067 
6068 .seealso: MatMultAdd(), MatMultTransposeAdd(), MatInterpolate()
6069 
6070 @*/
6071 PetscErrorCode PETSCMAT_DLLEXPORT MatRestrict(Mat A,Vec x,Vec y)
6072 {
6073   PetscErrorCode ierr;
6074   PetscInt       M,N;
6075 
6076   PetscFunctionBegin;
6077   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
6078   PetscValidHeaderSpecific(x,VEC_COOKIE,2);
6079   PetscValidHeaderSpecific(y,VEC_COOKIE,3);
6080   PetscValidType(A,1);
6081   ierr = MatPreallocated(A);CHKERRQ(ierr);
6082 
6083   ierr = MatGetSize(A,&M,&N);CHKERRQ(ierr);
6084   if (N > M) {
6085     ierr = MatMult(A,x,y);CHKERRQ(ierr);
6086   } else {
6087     ierr = MatMultTranspose(A,x,y);CHKERRQ(ierr);
6088   }
6089   PetscFunctionReturn(0);
6090 }
6091 
6092 #undef __FUNCT__
6093 #define __FUNCT__ "MatNullSpaceAttach"
6094 /*@
6095    MatNullSpaceAttach - attaches a null space to a matrix.
6096         This null space will be removed from the resulting vector whenever
6097         MatMult() is called
6098 
6099    Collective on Mat
6100 
6101    Input Parameters:
6102 +  mat - the matrix
6103 -  nullsp - the null space object
6104 
6105    Level: developer
6106 
6107    Notes:
6108       Overwrites any previous null space that may have been attached
6109 
6110    Concepts: null space^attaching to matrix
6111 
6112 .seealso: MatCreate(), MatNullSpaceCreate()
6113 @*/
6114 PetscErrorCode PETSCMAT_DLLEXPORT MatNullSpaceAttach(Mat mat,MatNullSpace nullsp)
6115 {
6116   PetscErrorCode ierr;
6117 
6118   PetscFunctionBegin;
6119   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6120   PetscValidType(mat,1);
6121   PetscValidHeaderSpecific(nullsp,MAT_NULLSPACE_COOKIE,2);
6122   ierr = MatPreallocated(mat);CHKERRQ(ierr);
6123   ierr = PetscObjectReference((PetscObject)nullsp);CHKERRQ(ierr);
6124   if (mat->nullsp) { ierr = MatNullSpaceDestroy(mat->nullsp);CHKERRQ(ierr); }
6125   mat->nullsp = nullsp;
6126   PetscFunctionReturn(0);
6127 }
6128 
6129 #undef __FUNCT__
6130 #define __FUNCT__ "MatICCFactor"
6131 /*@
6132    MatICCFactor - Performs in-place incomplete Cholesky factorization of matrix.
6133 
6134    Collective on Mat
6135 
6136    Input Parameters:
6137 +  mat - the matrix
6138 .  row - row/column permutation
6139 .  fill - expected fill factor >= 1.0
6140 -  level - level of fill, for ICC(k)
6141 
6142    Notes:
6143    Probably really in-place only when level of fill is zero, otherwise allocates
6144    new space to store factored matrix and deletes previous memory.
6145 
6146    Most users should employ the simplified KSP interface for linear solvers
6147    instead of working directly with matrix algebra routines such as this.
6148    See, e.g., KSPCreate().
6149 
6150    Level: developer
6151 
6152    Concepts: matrices^incomplete Cholesky factorization
6153    Concepts: Cholesky factorization
6154 
6155 .seealso: MatICCFactorSymbolic(), MatLUFactorNumeric(), MatCholeskyFactor()
6156 @*/
6157 PetscErrorCode PETSCMAT_DLLEXPORT MatICCFactor(Mat mat,IS row,MatFactorInfo* info)
6158 {
6159   PetscErrorCode ierr;
6160 
6161   PetscFunctionBegin;
6162   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6163   PetscValidType(mat,1);
6164   if (row) PetscValidHeaderSpecific(row,IS_COOKIE,2);
6165   PetscValidPointer(info,3);
6166   if (mat->rmap.N != mat->cmap.N) SETERRQ(PETSC_ERR_ARG_WRONG,"matrix must be square");
6167   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
6168   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
6169   if (!mat->ops->iccfactor) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
6170   ierr = MatPreallocated(mat);CHKERRQ(ierr);
6171   ierr = (*mat->ops->iccfactor)(mat,row,info);CHKERRQ(ierr);
6172   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
6173   PetscFunctionReturn(0);
6174 }
6175 
6176 #undef __FUNCT__
6177 #define __FUNCT__ "MatSetValuesAdic"
6178 /*@
6179    MatSetValuesAdic - Sets values computed with ADIC automatic differentiation into a matrix.
6180 
6181    Not Collective
6182 
6183    Input Parameters:
6184 +  mat - the matrix
6185 -  v - the values compute with ADIC
6186 
6187    Level: developer
6188 
6189    Notes:
6190      Must call MatSetColoring() before using this routine. Also this matrix must already
6191      have its nonzero pattern determined.
6192 
6193 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal(),
6194           MatSetValues(), MatSetColoring(), MatSetValuesAdifor()
6195 @*/
6196 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesAdic(Mat mat,void *v)
6197 {
6198   PetscErrorCode ierr;
6199 
6200   PetscFunctionBegin;
6201   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6202   PetscValidType(mat,1);
6203   PetscValidPointer(mat,2);
6204 
6205   if (!mat->assembled) {
6206     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Matrix must be already assembled");
6207   }
6208   ierr = PetscLogEventBegin(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
6209   if (!mat->ops->setvaluesadic) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
6210   ierr = (*mat->ops->setvaluesadic)(mat,v);CHKERRQ(ierr);
6211   ierr = PetscLogEventEnd(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
6212   ierr = MatView_Private(mat);CHKERRQ(ierr);
6213   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
6214   PetscFunctionReturn(0);
6215 }
6216 
6217 
6218 #undef __FUNCT__
6219 #define __FUNCT__ "MatSetColoring"
6220 /*@
6221    MatSetColoring - Sets a coloring used by calls to MatSetValuesAdic()
6222 
6223    Not Collective
6224 
6225    Input Parameters:
6226 +  mat - the matrix
6227 -  coloring - the coloring
6228 
6229    Level: developer
6230 
6231 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal(),
6232           MatSetValues(), MatSetValuesAdic()
6233 @*/
6234 PetscErrorCode PETSCMAT_DLLEXPORT MatSetColoring(Mat mat,ISColoring coloring)
6235 {
6236   PetscErrorCode ierr;
6237 
6238   PetscFunctionBegin;
6239   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6240   PetscValidType(mat,1);
6241   PetscValidPointer(coloring,2);
6242 
6243   if (!mat->assembled) {
6244     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Matrix must be already assembled");
6245   }
6246   if (!mat->ops->setcoloring) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
6247   ierr = (*mat->ops->setcoloring)(mat,coloring);CHKERRQ(ierr);
6248   PetscFunctionReturn(0);
6249 }
6250 
6251 #undef __FUNCT__
6252 #define __FUNCT__ "MatSetValuesAdifor"
6253 /*@
6254    MatSetValuesAdifor - Sets values computed with automatic differentiation into a matrix.
6255 
6256    Not Collective
6257 
6258    Input Parameters:
6259 +  mat - the matrix
6260 .  nl - leading dimension of v
6261 -  v - the values compute with ADIFOR
6262 
6263    Level: developer
6264 
6265    Notes:
6266      Must call MatSetColoring() before using this routine. Also this matrix must already
6267      have its nonzero pattern determined.
6268 
6269 .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal(),
6270           MatSetValues(), MatSetColoring()
6271 @*/
6272 PetscErrorCode PETSCMAT_DLLEXPORT MatSetValuesAdifor(Mat mat,PetscInt nl,void *v)
6273 {
6274   PetscErrorCode ierr;
6275 
6276   PetscFunctionBegin;
6277   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6278   PetscValidType(mat,1);
6279   PetscValidPointer(v,3);
6280 
6281   if (!mat->assembled) {
6282     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Matrix must be already assembled");
6283   }
6284   ierr = PetscLogEventBegin(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
6285   if (!mat->ops->setvaluesadifor) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
6286   ierr = (*mat->ops->setvaluesadifor)(mat,nl,v);CHKERRQ(ierr);
6287   ierr = PetscLogEventEnd(MAT_SetValues,mat,0,0,0);CHKERRQ(ierr);
6288   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
6289   PetscFunctionReturn(0);
6290 }
6291 
6292 #undef __FUNCT__
6293 #define __FUNCT__ "MatDiagonalScaleLocal"
6294 /*@
6295    MatDiagonalScaleLocal - Scales columns of a matrix given the scaling values including the
6296          ghosted ones.
6297 
6298    Not Collective
6299 
6300    Input Parameters:
6301 +  mat - the matrix
6302 -  diag = the diagonal values, including ghost ones
6303 
6304    Level: developer
6305 
6306    Notes: Works only for MPIAIJ and MPIBAIJ matrices
6307 
6308 .seealso: MatDiagonalScale()
6309 @*/
6310 PetscErrorCode PETSCMAT_DLLEXPORT MatDiagonalScaleLocal(Mat mat,Vec diag)
6311 {
6312   PetscErrorCode ierr;
6313   PetscMPIInt    size;
6314 
6315   PetscFunctionBegin;
6316   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6317   PetscValidHeaderSpecific(diag,VEC_COOKIE,2);
6318   PetscValidType(mat,1);
6319 
6320   if (!mat->assembled) {
6321     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Matrix must be already assembled");
6322   }
6323   ierr = PetscLogEventBegin(MAT_Scale,mat,0,0,0);CHKERRQ(ierr);
6324   ierr = MPI_Comm_size(((PetscObject)mat)->comm,&size);CHKERRQ(ierr);
6325   if (size == 1) {
6326     PetscInt n,m;
6327     ierr = VecGetSize(diag,&n);CHKERRQ(ierr);
6328     ierr = MatGetSize(mat,0,&m);CHKERRQ(ierr);
6329     if (m == n) {
6330       ierr = MatDiagonalScale(mat,0,diag);CHKERRQ(ierr);
6331     } else {
6332       SETERRQ(PETSC_ERR_SUP,"Only supported for sequential matrices when no ghost points/periodic conditions");
6333     }
6334   } else {
6335     PetscErrorCode (*f)(Mat,Vec);
6336     ierr = PetscObjectQueryFunction((PetscObject)mat,"MatDiagonalScaleLocal_C",(void (**)(void))&f);CHKERRQ(ierr);
6337     if (f) {
6338       ierr = (*f)(mat,diag);CHKERRQ(ierr);
6339     } else {
6340       SETERRQ(PETSC_ERR_SUP,"Only supported for MPIAIJ and MPIBAIJ parallel matrices");
6341     }
6342   }
6343   ierr = PetscLogEventEnd(MAT_Scale,mat,0,0,0);CHKERRQ(ierr);
6344   ierr = PetscObjectStateIncrease((PetscObject)mat);CHKERRQ(ierr);
6345   PetscFunctionReturn(0);
6346 }
6347 
6348 #undef __FUNCT__
6349 #define __FUNCT__ "MatGetInertia"
6350 /*@
6351    MatGetInertia - Gets the inertia from a factored matrix
6352 
6353    Collective on Mat
6354 
6355    Input Parameter:
6356 .  mat - the matrix
6357 
6358    Output Parameters:
6359 +   nneg - number of negative eigenvalues
6360 .   nzero - number of zero eigenvalues
6361 -   npos - number of positive eigenvalues
6362 
6363    Level: advanced
6364 
6365    Notes: Matrix must have been factored by MatCholeskyFactor()
6366 
6367 
6368 @*/
6369 PetscErrorCode PETSCMAT_DLLEXPORT MatGetInertia(Mat mat,PetscInt *nneg,PetscInt *nzero,PetscInt *npos)
6370 {
6371   PetscErrorCode ierr;
6372 
6373   PetscFunctionBegin;
6374   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6375   PetscValidType(mat,1);
6376   if (!mat->factor)    SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
6377   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Numeric factor mat is not assembled");
6378   if (!mat->ops->getinertia) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
6379   ierr = (*mat->ops->getinertia)(mat,nneg,nzero,npos);CHKERRQ(ierr);
6380   PetscFunctionReturn(0);
6381 }
6382 
6383 /* ----------------------------------------------------------------*/
6384 #undef __FUNCT__
6385 #define __FUNCT__ "MatSolves"
6386 /*@
6387    MatSolves - Solves A x = b, given a factored matrix, for a collection of vectors
6388 
6389    Collective on Mat and Vecs
6390 
6391    Input Parameters:
6392 +  mat - the factored matrix
6393 -  b - the right-hand-side vectors
6394 
6395    Output Parameter:
6396 .  x - the result vectors
6397 
6398    Notes:
6399    The vectors b and x cannot be the same.  I.e., one cannot
6400    call MatSolves(A,x,x).
6401 
6402    Notes:
6403    Most users should employ the simplified KSP interface for linear solvers
6404    instead of working directly with matrix algebra routines such as this.
6405    See, e.g., KSPCreate().
6406 
6407    Level: developer
6408 
6409    Concepts: matrices^triangular solves
6410 
6411 .seealso: MatSolveAdd(), MatSolveTranspose(), MatSolveTransposeAdd(), MatSolve()
6412 @*/
6413 PetscErrorCode PETSCMAT_DLLEXPORT MatSolves(Mat mat,Vecs b,Vecs x)
6414 {
6415   PetscErrorCode ierr;
6416 
6417   PetscFunctionBegin;
6418   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6419   PetscValidType(mat,1);
6420   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
6421   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
6422   if (!mat->rmap.N && !mat->cmap.N) PetscFunctionReturn(0);
6423 
6424   if (!mat->ops->solves) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
6425   ierr = MatPreallocated(mat);CHKERRQ(ierr);
6426   ierr = PetscLogEventBegin(MAT_Solves,mat,0,0,0);CHKERRQ(ierr);
6427   ierr = (*mat->ops->solves)(mat,b,x);CHKERRQ(ierr);
6428   ierr = PetscLogEventEnd(MAT_Solves,mat,0,0,0);CHKERRQ(ierr);
6429   PetscFunctionReturn(0);
6430 }
6431 
6432 #undef __FUNCT__
6433 #define __FUNCT__ "MatIsSymmetric"
6434 /*@
6435    MatIsSymmetric - Test whether a matrix is symmetric
6436 
6437    Collective on Mat
6438 
6439    Input Parameter:
6440 +  A - the matrix to test
6441 -  tol - difference between value and its transpose less than this amount counts as equal (use 0.0 for exact transpose)
6442 
6443    Output Parameters:
6444 .  flg - the result
6445 
6446    Level: intermediate
6447 
6448    Concepts: matrix^symmetry
6449 
6450 .seealso: MatTranspose(), MatIsTranspose(), MatIsHermitian(), MatIsStructurallySymmetric(), MatSetOption(), MatIsSymmetricKnown()
6451 @*/
6452 PetscErrorCode PETSCMAT_DLLEXPORT MatIsSymmetric(Mat A,PetscReal tol,PetscTruth *flg)
6453 {
6454   PetscErrorCode ierr;
6455 
6456   PetscFunctionBegin;
6457   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
6458   PetscValidPointer(flg,2);
6459   if (!A->symmetric_set) {
6460     if (!A->ops->issymmetric) {
6461       MatType mattype;
6462       ierr = MatGetType(A,&mattype);CHKERRQ(ierr);
6463       SETERRQ1(PETSC_ERR_SUP,"Matrix of type <%s> does not support checking for symmetric",mattype);
6464     }
6465     ierr = (*A->ops->issymmetric)(A,tol,&A->symmetric);CHKERRQ(ierr);
6466     A->symmetric_set = PETSC_TRUE;
6467     if (A->symmetric) {
6468       A->structurally_symmetric_set = PETSC_TRUE;
6469       A->structurally_symmetric     = PETSC_TRUE;
6470     }
6471   }
6472   *flg = A->symmetric;
6473   PetscFunctionReturn(0);
6474 }
6475 
6476 #undef __FUNCT__
6477 #define __FUNCT__ "MatIsHermitian"
6478 /*@
6479    MatIsHermitian - Test whether a matrix is Hermitian
6480 
6481    Collective on Mat
6482 
6483    Input Parameter:
6484 +  A - the matrix to test
6485 -  tol - difference between value and its transpose less than this amount counts as equal (use 0.0 for exact Hermitian)
6486 
6487    Output Parameters:
6488 .  flg - the result
6489 
6490    Level: intermediate
6491 
6492    Concepts: matrix^symmetry
6493 
6494 .seealso: MatTranspose(), MatIsTranspose(), MatIsHermitian(), MatIsStructurallySymmetric(), MatSetOption(), MatIsSymmetricKnown()
6495 @*/
6496 PetscErrorCode PETSCMAT_DLLEXPORT MatIsHermitian(Mat A,PetscReal tol,PetscTruth *flg)
6497 {
6498   PetscErrorCode ierr;
6499 
6500   PetscFunctionBegin;
6501   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
6502   PetscValidPointer(flg,2);
6503   if (!A->hermitian_set) {
6504     if (!A->ops->ishermitian) {
6505       MatType mattype;
6506       ierr = MatGetType(A,&mattype);CHKERRQ(ierr);
6507       SETERRQ1(PETSC_ERR_SUP,"Matrix of type <%s> does not support checking for Hermitian",mattype);
6508     }
6509     ierr = (*A->ops->ishermitian)(A,tol,&A->hermitian);CHKERRQ(ierr);
6510     A->hermitian_set = PETSC_TRUE;
6511     if (A->hermitian) {
6512       A->structurally_symmetric_set = PETSC_TRUE;
6513       A->structurally_symmetric     = PETSC_TRUE;
6514     }
6515   }
6516   *flg = A->hermitian;
6517   PetscFunctionReturn(0);
6518 }
6519 
6520 #undef __FUNCT__
6521 #define __FUNCT__ "MatIsSymmetricKnown"
6522 /*@
6523    MatIsSymmetricKnown - Checks the flag on the matrix to see if it is symmetric.
6524 
6525    Collective on Mat
6526 
6527    Input Parameter:
6528 .  A - the matrix to check
6529 
6530    Output Parameters:
6531 +  set - if the symmetric flag is set (this tells you if the next flag is valid)
6532 -  flg - the result
6533 
6534    Level: advanced
6535 
6536    Concepts: matrix^symmetry
6537 
6538    Note: Does not check the matrix values directly, so this may return unknown (set = PETSC_FALSE). Use MatIsSymmetric()
6539          if you want it explicitly checked
6540 
6541 .seealso: MatTranspose(), MatIsTranspose(), MatIsHermitian(), MatIsStructurallySymmetric(), MatSetOption(), MatIsSymmetric()
6542 @*/
6543 PetscErrorCode PETSCMAT_DLLEXPORT MatIsSymmetricKnown(Mat A,PetscTruth *set,PetscTruth *flg)
6544 {
6545   PetscFunctionBegin;
6546   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
6547   PetscValidPointer(set,2);
6548   PetscValidPointer(flg,3);
6549   if (A->symmetric_set) {
6550     *set = PETSC_TRUE;
6551     *flg = A->symmetric;
6552   } else {
6553     *set = PETSC_FALSE;
6554   }
6555   PetscFunctionReturn(0);
6556 }
6557 
6558 #undef __FUNCT__
6559 #define __FUNCT__ "MatIsHermitianKnown"
6560 /*@
6561    MatIsHermitianKnown - Checks the flag on the matrix to see if it is hermitian.
6562 
6563    Collective on Mat
6564 
6565    Input Parameter:
6566 .  A - the matrix to check
6567 
6568    Output Parameters:
6569 +  set - if the hermitian flag is set (this tells you if the next flag is valid)
6570 -  flg - the result
6571 
6572    Level: advanced
6573 
6574    Concepts: matrix^symmetry
6575 
6576    Note: Does not check the matrix values directly, so this may return unknown (set = PETSC_FALSE). Use MatIsHermitian()
6577          if you want it explicitly checked
6578 
6579 .seealso: MatTranspose(), MatIsTranspose(), MatIsHermitian(), MatIsStructurallySymmetric(), MatSetOption(), MatIsSymmetric()
6580 @*/
6581 PetscErrorCode PETSCMAT_DLLEXPORT MatIsHermitianKnown(Mat A,PetscTruth *set,PetscTruth *flg)
6582 {
6583   PetscFunctionBegin;
6584   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
6585   PetscValidPointer(set,2);
6586   PetscValidPointer(flg,3);
6587   if (A->hermitian_set) {
6588     *set = PETSC_TRUE;
6589     *flg = A->hermitian;
6590   } else {
6591     *set = PETSC_FALSE;
6592   }
6593   PetscFunctionReturn(0);
6594 }
6595 
6596 #undef __FUNCT__
6597 #define __FUNCT__ "MatIsStructurallySymmetric"
6598 /*@
6599    MatIsStructurallySymmetric - Test whether a matrix is structurally symmetric
6600 
6601    Collective on Mat
6602 
6603    Input Parameter:
6604 .  A - the matrix to test
6605 
6606    Output Parameters:
6607 .  flg - the result
6608 
6609    Level: intermediate
6610 
6611    Concepts: matrix^symmetry
6612 
6613 .seealso: MatTranspose(), MatIsTranspose(), MatIsHermitian(), MatIsSymmetric(), MatSetOption()
6614 @*/
6615 PetscErrorCode PETSCMAT_DLLEXPORT MatIsStructurallySymmetric(Mat A,PetscTruth *flg)
6616 {
6617   PetscErrorCode ierr;
6618 
6619   PetscFunctionBegin;
6620   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
6621   PetscValidPointer(flg,2);
6622   if (!A->structurally_symmetric_set) {
6623     if (!A->ops->isstructurallysymmetric) SETERRQ(PETSC_ERR_SUP,"Matrix does not support checking for structural symmetric");
6624     ierr = (*A->ops->isstructurallysymmetric)(A,&A->structurally_symmetric);CHKERRQ(ierr);
6625     A->structurally_symmetric_set = PETSC_TRUE;
6626   }
6627   *flg = A->structurally_symmetric;
6628   PetscFunctionReturn(0);
6629 }
6630 
6631 #undef __FUNCT__
6632 #define __FUNCT__ "MatStashGetInfo"
6633 extern PetscErrorCode MatStashGetInfo_Private(MatStash*,PetscInt*,PetscInt*);
6634 /*@
6635    MatStashGetInfo - Gets how many values are currently in the vector stash, i.e. need
6636        to be communicated to other processors during the MatAssemblyBegin/End() process
6637 
6638     Not collective
6639 
6640    Input Parameter:
6641 .   vec - the vector
6642 
6643    Output Parameters:
6644 +   nstash   - the size of the stash
6645 .   reallocs - the number of additional mallocs incurred.
6646 .   bnstash   - the size of the block stash
6647 -   breallocs - the number of additional mallocs incurred.in the block stash
6648 
6649    Level: advanced
6650 
6651 .seealso: MatAssemblyBegin(), MatAssemblyEnd(), Mat, MatStashSetInitialSize()
6652 
6653 @*/
6654 PetscErrorCode PETSCMAT_DLLEXPORT MatStashGetInfo(Mat mat,PetscInt *nstash,PetscInt *reallocs,PetscInt *bnstash,PetscInt *breallocs)
6655 {
6656   PetscErrorCode ierr;
6657   PetscFunctionBegin;
6658   ierr = MatStashGetInfo_Private(&mat->stash,nstash,reallocs);CHKERRQ(ierr);
6659   ierr = MatStashGetInfo_Private(&mat->bstash,bnstash,breallocs);CHKERRQ(ierr);
6660   PetscFunctionReturn(0);
6661 }
6662 
6663 #undef __FUNCT__
6664 #define __FUNCT__ "MatGetVecs"
6665 /*@C
6666    MatGetVecs - Get vector(s) compatible with the matrix, i.e. with the same
6667      parallel layout
6668 
6669    Collective on Mat
6670 
6671    Input Parameter:
6672 .  mat - the matrix
6673 
6674    Output Parameter:
6675 +   right - (optional) vector that the matrix can be multiplied against
6676 -   left - (optional) vector that the matrix vector product can be stored in
6677 
6678   Level: advanced
6679 
6680 .seealso: MatCreate()
6681 @*/
6682 PetscErrorCode PETSCMAT_DLLEXPORT MatGetVecs(Mat mat,Vec *right,Vec *left)
6683 {
6684   PetscErrorCode ierr;
6685 
6686   PetscFunctionBegin;
6687   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
6688   PetscValidType(mat,1);
6689   ierr = MatPreallocated(mat);CHKERRQ(ierr);
6690   if (mat->ops->getvecs) {
6691     ierr = (*mat->ops->getvecs)(mat,right,left);CHKERRQ(ierr);
6692   } else {
6693     PetscMPIInt size;
6694     ierr = MPI_Comm_size(((PetscObject)mat)->comm, &size);CHKERRQ(ierr);
6695     if (right) {
6696       ierr = VecCreate(((PetscObject)mat)->comm,right);CHKERRQ(ierr);
6697       ierr = VecSetSizes(*right,mat->cmap.n,PETSC_DETERMINE);CHKERRQ(ierr);
6698       if (size > 1) {ierr = VecSetType(*right,VECMPI);CHKERRQ(ierr);}
6699       else {ierr = VecSetType(*right,VECSEQ);CHKERRQ(ierr);}
6700     }
6701     if (left) {
6702       ierr = VecCreate(((PetscObject)mat)->comm,left);CHKERRQ(ierr);
6703       ierr = VecSetSizes(*left,mat->rmap.n,PETSC_DETERMINE);CHKERRQ(ierr);
6704       if (size > 1) {ierr = VecSetType(*left,VECMPI);CHKERRQ(ierr);}
6705       else {ierr = VecSetType(*left,VECSEQ);CHKERRQ(ierr);}
6706     }
6707   }
6708   if (right) {ierr = VecSetBlockSize(*right,mat->rmap.bs);CHKERRQ(ierr);}
6709   if (left) {ierr = VecSetBlockSize(*left,mat->rmap.bs);CHKERRQ(ierr);}
6710   if (mat->mapping) {
6711     if (right) {ierr = VecSetLocalToGlobalMapping(*right,mat->mapping);CHKERRQ(ierr);}
6712     if (left) {ierr = VecSetLocalToGlobalMapping(*left,mat->mapping);CHKERRQ(ierr);}
6713   }
6714   if (mat->bmapping) {
6715     if (right) {ierr = VecSetLocalToGlobalMappingBlock(*right,mat->bmapping);CHKERRQ(ierr);}
6716     if (left) {ierr = VecSetLocalToGlobalMappingBlock(*left,mat->bmapping);CHKERRQ(ierr);}
6717   }
6718   PetscFunctionReturn(0);
6719 }
6720 
6721 #undef __FUNCT__
6722 #define __FUNCT__ "MatFactorInfoInitialize"
6723 /*@
6724    MatFactorInfoInitialize - Initializes a MatFactorInfo data structure
6725      with default values.
6726 
6727    Not Collective
6728 
6729    Input Parameters:
6730 .    info - the MatFactorInfo data structure
6731 
6732 
6733    Notes: The solvers are generally used through the KSP and PC objects, for example
6734           PCLU, PCILU, PCCHOLESKY, PCICC
6735 
6736    Level: developer
6737 
6738 .seealso: MatFactorInfo
6739 @*/
6740 
6741 PetscErrorCode PETSCMAT_DLLEXPORT MatFactorInfoInitialize(MatFactorInfo *info)
6742 {
6743   PetscErrorCode ierr;
6744 
6745   PetscFunctionBegin;
6746   ierr = PetscMemzero(info,sizeof(MatFactorInfo));CHKERRQ(ierr);
6747   PetscFunctionReturn(0);
6748 }
6749 
6750 #undef __FUNCT__
6751 #define __FUNCT__ "MatPtAP"
6752 /*@
6753    MatPtAP - Creates the matrix projection C = P^T * A * P
6754 
6755    Collective on Mat
6756 
6757    Input Parameters:
6758 +  A - the matrix
6759 .  P - the projection matrix
6760 .  scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
6761 -  fill - expected fill as ratio of nnz(C)/nnz(A)
6762 
6763    Output Parameters:
6764 .  C - the product matrix
6765 
6766    Notes:
6767    C will be created and must be destroyed by the user with MatDestroy().
6768 
6769    This routine is currently only implemented for pairs of AIJ matrices and classes
6770    which inherit from AIJ.
6771 
6772    Level: intermediate
6773 
6774 .seealso: MatPtAPSymbolic(), MatPtAPNumeric(), MatMatMult()
6775 @*/
6776 PetscErrorCode PETSCMAT_DLLEXPORT MatPtAP(Mat A,Mat P,MatReuse scall,PetscReal fill,Mat *C)
6777 {
6778   PetscErrorCode ierr;
6779 
6780   PetscFunctionBegin;
6781   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
6782   PetscValidType(A,1);
6783   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
6784   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
6785   PetscValidHeaderSpecific(P,MAT_COOKIE,2);
6786   PetscValidType(P,2);
6787   MatPreallocated(P);
6788   if (!P->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
6789   if (P->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
6790   PetscValidPointer(C,3);
6791   if (P->rmap.N!=A->cmap.N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",P->rmap.N,A->cmap.N);
6792   if (fill < 1.0) SETERRQ1(PETSC_ERR_ARG_SIZ,"Expected fill=%G must be >= 1.0",fill);
6793   ierr = MatPreallocated(A);CHKERRQ(ierr);
6794 
6795   ierr = PetscLogEventBegin(MAT_PtAP,A,P,0,0);CHKERRQ(ierr);
6796   ierr = (*A->ops->ptap)(A,P,scall,fill,C);CHKERRQ(ierr);
6797   ierr = PetscLogEventEnd(MAT_PtAP,A,P,0,0);CHKERRQ(ierr);
6798 
6799   PetscFunctionReturn(0);
6800 }
6801 
6802 #undef __FUNCT__
6803 #define __FUNCT__ "MatPtAPNumeric"
6804 /*@
6805    MatPtAPNumeric - Computes the matrix projection C = P^T * A * P
6806 
6807    Collective on Mat
6808 
6809    Input Parameters:
6810 +  A - the matrix
6811 -  P - the projection matrix
6812 
6813    Output Parameters:
6814 .  C - the product matrix
6815 
6816    Notes:
6817    C must have been created by calling MatPtAPSymbolic and must be destroyed by
6818    the user using MatDeatroy().
6819 
6820    This routine is currently only implemented for pairs of AIJ matrices and classes
6821    which inherit from AIJ.  C will be of type MATAIJ.
6822 
6823    Level: intermediate
6824 
6825 .seealso: MatPtAP(), MatPtAPSymbolic(), MatMatMultNumeric()
6826 @*/
6827 PetscErrorCode PETSCMAT_DLLEXPORT MatPtAPNumeric(Mat A,Mat P,Mat C)
6828 {
6829   PetscErrorCode ierr;
6830 
6831   PetscFunctionBegin;
6832   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
6833   PetscValidType(A,1);
6834   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
6835   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
6836   PetscValidHeaderSpecific(P,MAT_COOKIE,2);
6837   PetscValidType(P,2);
6838   MatPreallocated(P);
6839   if (!P->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
6840   if (P->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
6841   PetscValidHeaderSpecific(C,MAT_COOKIE,3);
6842   PetscValidType(C,3);
6843   MatPreallocated(C);
6844   if (C->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
6845   if (P->cmap.N!=C->rmap.N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",P->cmap.N,C->rmap.N);
6846   if (P->rmap.N!=A->cmap.N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",P->rmap.N,A->cmap.N);
6847   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);
6848   if (P->cmap.N!=C->cmap.N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",P->cmap.N,C->cmap.N);
6849   ierr = MatPreallocated(A);CHKERRQ(ierr);
6850 
6851   ierr = PetscLogEventBegin(MAT_PtAPNumeric,A,P,0,0);CHKERRQ(ierr);
6852   ierr = (*A->ops->ptapnumeric)(A,P,C);CHKERRQ(ierr);
6853   ierr = PetscLogEventEnd(MAT_PtAPNumeric,A,P,0,0);CHKERRQ(ierr);
6854   PetscFunctionReturn(0);
6855 }
6856 
6857 #undef __FUNCT__
6858 #define __FUNCT__ "MatPtAPSymbolic"
6859 /*@
6860    MatPtAPSymbolic - Creates the (i,j) structure of the matrix projection C = P^T * A * P
6861 
6862    Collective on Mat
6863 
6864    Input Parameters:
6865 +  A - the matrix
6866 -  P - the projection matrix
6867 
6868    Output Parameters:
6869 .  C - the (i,j) structure of the product matrix
6870 
6871    Notes:
6872    C will be created and must be destroyed by the user with MatDestroy().
6873 
6874    This routine is currently only implemented for pairs of SeqAIJ matrices and classes
6875    which inherit from SeqAIJ.  C will be of type MATSEQAIJ.  The product is computed using
6876    this (i,j) structure by calling MatPtAPNumeric().
6877 
6878    Level: intermediate
6879 
6880 .seealso: MatPtAP(), MatPtAPNumeric(), MatMatMultSymbolic()
6881 @*/
6882 PetscErrorCode PETSCMAT_DLLEXPORT MatPtAPSymbolic(Mat A,Mat P,PetscReal fill,Mat *C)
6883 {
6884   PetscErrorCode ierr;
6885 
6886   PetscFunctionBegin;
6887   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
6888   PetscValidType(A,1);
6889   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
6890   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
6891   if (fill <1.0) SETERRQ1(PETSC_ERR_ARG_SIZ,"Expected fill=%G must be >= 1.0",fill);
6892   PetscValidHeaderSpecific(P,MAT_COOKIE,2);
6893   PetscValidType(P,2);
6894   MatPreallocated(P);
6895   if (!P->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
6896   if (P->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
6897   PetscValidPointer(C,3);
6898 
6899   if (P->rmap.N!=A->cmap.N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",P->rmap.N,A->cmap.N);
6900   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);
6901   ierr = MatPreallocated(A);CHKERRQ(ierr);
6902   ierr = PetscLogEventBegin(MAT_PtAPSymbolic,A,P,0,0);CHKERRQ(ierr);
6903   ierr = (*A->ops->ptapsymbolic)(A,P,fill,C);CHKERRQ(ierr);
6904   ierr = PetscLogEventEnd(MAT_PtAPSymbolic,A,P,0,0);CHKERRQ(ierr);
6905 
6906   ierr = MatSetBlockSize(*C,A->rmap.bs);CHKERRQ(ierr);
6907 
6908   PetscFunctionReturn(0);
6909 }
6910 
6911 #undef __FUNCT__
6912 #define __FUNCT__ "MatMatMult"
6913 /*@
6914    MatMatMult - Performs Matrix-Matrix Multiplication C=A*B.
6915 
6916    Collective on Mat
6917 
6918    Input Parameters:
6919 +  A - the left matrix
6920 .  B - the right matrix
6921 .  scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
6922 -  fill - expected fill as ratio of nnz(C)/(nnz(A) + nnz(B)), if the result is a dense matrix this is irrelevent
6923 
6924    Output Parameters:
6925 .  C - the product matrix
6926 
6927    Notes:
6928    Unless scall is MAT_REUSE_MATRIX C will be created.
6929 
6930    If you have many matrices with the same non-zero structure to multiply, you
6931    should either
6932 $   1) use MAT_REUSE_MATRIX in all calls but the first or
6933 $   2) call MatMatMultSymbolic() once and then MatMatMultNumeric() for each product needed
6934 
6935    Level: intermediate
6936 
6937 .seealso: MatMatMultSymbolic(), MatMatMultNumeric(), MatPtAP()
6938 @*/
6939 PetscErrorCode PETSCMAT_DLLEXPORT MatMatMult(Mat A,Mat B,MatReuse scall,PetscReal fill,Mat *C)
6940 {
6941   PetscErrorCode ierr;
6942   PetscErrorCode (*fA)(Mat,Mat,MatReuse,PetscReal,Mat*);
6943   PetscErrorCode (*fB)(Mat,Mat,MatReuse,PetscReal,Mat*);
6944   PetscErrorCode (*mult)(Mat,Mat,MatReuse,PetscReal,Mat *)=PETSC_NULL;
6945 
6946   PetscFunctionBegin;
6947   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
6948   PetscValidType(A,1);
6949   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
6950   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
6951   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
6952   PetscValidType(B,2);
6953   MatPreallocated(B);
6954   if (!B->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
6955   if (B->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
6956   PetscValidPointer(C,3);
6957   if (B->rmap.N!=A->cmap.N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",B->rmap.N,A->cmap.N);
6958   if (scall == MAT_REUSE_MATRIX){
6959     PetscValidPointer(*C,5);
6960     PetscValidHeaderSpecific(*C,MAT_COOKIE,5);
6961   }
6962   if (fill == PETSC_DEFAULT) fill = 2.0;
6963   if (fill < 1.0) SETERRQ1(PETSC_ERR_ARG_SIZ,"Expected fill=%G must be >= 1.0",fill);
6964   ierr = MatPreallocated(A);CHKERRQ(ierr);
6965 
6966   fA = A->ops->matmult;
6967   fB = B->ops->matmult;
6968   if (fB == fA) {
6969     if (!fB) SETERRQ1(PETSC_ERR_SUP,"MatMatMult not supported for B of type %s",((PetscObject)B)->type_name);
6970     mult = fB;
6971   } else {
6972     /* dispatch based on the type of A and B */
6973     char  multname[256];
6974     ierr = PetscStrcpy(multname,"MatMatMult_");CHKERRQ(ierr);
6975     ierr = PetscStrcat(multname,((PetscObject)A)->type_name);CHKERRQ(ierr);
6976     ierr = PetscStrcat(multname,"_");CHKERRQ(ierr);
6977     ierr = PetscStrcat(multname,((PetscObject)B)->type_name);CHKERRQ(ierr);
6978     ierr = PetscStrcat(multname,"_C");CHKERRQ(ierr); /* e.g., multname = "MatMatMult_seqdense_seqaij_C" */
6979     ierr = PetscObjectQueryFunction((PetscObject)B,multname,(void (**)(void))&mult);CHKERRQ(ierr);
6980     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);
6981   }
6982   ierr = PetscLogEventBegin(MAT_MatMult,A,B,0,0);CHKERRQ(ierr);
6983   ierr = (*mult)(A,B,scall,fill,C);CHKERRQ(ierr);
6984   ierr = PetscLogEventEnd(MAT_MatMult,A,B,0,0);CHKERRQ(ierr);
6985   PetscFunctionReturn(0);
6986 }
6987 
6988 #undef __FUNCT__
6989 #define __FUNCT__ "MatMatMultSymbolic"
6990 /*@
6991    MatMatMultSymbolic - Performs construction, preallocation, and computes the ij structure
6992    of the matrix-matrix product C=A*B.  Call this routine before calling MatMatMultNumeric().
6993 
6994    Collective on Mat
6995 
6996    Input Parameters:
6997 +  A - the left matrix
6998 .  B - the right matrix
6999 -  fill - expected fill as ratio of nnz(C)/(nnz(A) + nnz(B)), if C is a dense matrix this is irrelevent
7000 
7001    Output Parameters:
7002 .  C - the matrix ready for the numeric part of the multiplication
7003 
7004    This routine is currently implemented for
7005     - pairs of AIJ matrices and classes which inherit from AIJ, C will be of type AIJ
7006     - pairs of AIJ (A) and Dense (B) matrix, C will be of type Dense.
7007     - pairs of Dense (A) and AIJ (B) matrix, C will be of type Dense.
7008 
7009    Level: intermediate
7010 
7011 .seealso: MatMatMult(), MatMatMultNumeric()
7012 @*/
7013 PetscErrorCode PETSCMAT_DLLEXPORT MatMatMultSymbolic(Mat A,Mat B,PetscReal fill,Mat *C)
7014 {
7015   PetscErrorCode ierr;
7016   PetscErrorCode (*Asymbolic)(Mat,Mat,PetscReal,Mat *);
7017   PetscErrorCode (*Bsymbolic)(Mat,Mat,PetscReal,Mat *);
7018   PetscErrorCode (*symbolic)(Mat,Mat,PetscReal,Mat *)=PETSC_NULL;
7019 
7020   PetscFunctionBegin;
7021   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
7022   PetscValidType(A,1);
7023   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7024   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7025 
7026   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
7027   PetscValidType(B,2);
7028   MatPreallocated(B);
7029   if (!B->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7030   if (B->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7031   PetscValidPointer(C,3);
7032 
7033   if (B->rmap.N!=A->cmap.N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",B->rmap.N,A->cmap.N);
7034   if (fill == PETSC_DEFAULT) fill = 2.0;
7035   if (fill < 1.0) SETERRQ1(PETSC_ERR_ARG_SIZ,"Expected fill=%G must be > 1.0",fill);
7036   ierr = MatPreallocated(A);CHKERRQ(ierr);
7037 
7038   Asymbolic = A->ops->matmultsymbolic;
7039   Bsymbolic = B->ops->matmultsymbolic;
7040   if (Asymbolic == Bsymbolic){
7041     if (!Bsymbolic) SETERRQ1(PETSC_ERR_SUP,"C=A*B not implemented for B of type %s",((PetscObject)B)->type_name);
7042     symbolic = Bsymbolic;
7043   } else { /* dispatch based on the type of A and B */
7044     char  symbolicname[256];
7045     ierr = PetscStrcpy(symbolicname,"MatMatMultSymbolic_");CHKERRQ(ierr);
7046     ierr = PetscStrcat(symbolicname,((PetscObject)A)->type_name);CHKERRQ(ierr);
7047     ierr = PetscStrcat(symbolicname,"_");CHKERRQ(ierr);
7048     ierr = PetscStrcat(symbolicname,((PetscObject)B)->type_name);CHKERRQ(ierr);
7049     ierr = PetscStrcat(symbolicname,"_C");CHKERRQ(ierr);
7050     ierr = PetscObjectQueryFunction((PetscObject)B,symbolicname,(void (**)(void))&symbolic);CHKERRQ(ierr);
7051     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);
7052   }
7053   ierr = PetscLogEventBegin(MAT_MatMultSymbolic,A,B,0,0);CHKERRQ(ierr);
7054   ierr = (*symbolic)(A,B,fill,C);CHKERRQ(ierr);
7055   ierr = PetscLogEventEnd(MAT_MatMultSymbolic,A,B,0,0);CHKERRQ(ierr);
7056   PetscFunctionReturn(0);
7057 }
7058 
7059 #undef __FUNCT__
7060 #define __FUNCT__ "MatMatMultNumeric"
7061 /*@
7062    MatMatMultNumeric - Performs the numeric matrix-matrix product.
7063    Call this routine after first calling MatMatMultSymbolic().
7064 
7065    Collective on Mat
7066 
7067    Input Parameters:
7068 +  A - the left matrix
7069 -  B - the right matrix
7070 
7071    Output Parameters:
7072 .  C - the product matrix, which was created by from MatMatMultSymbolic() or a call to MatMatMult().
7073 
7074    Notes:
7075    C must have been created with MatMatMultSymbolic().
7076 
7077    This routine is currently implemented for
7078     - pairs of AIJ matrices and classes which inherit from AIJ, C will be of type MATAIJ.
7079     - pairs of AIJ (A) and Dense (B) matrix, C will be of type Dense.
7080     - pairs of Dense (A) and AIJ (B) matrix, C will be of type Dense.
7081 
7082    Level: intermediate
7083 
7084 .seealso: MatMatMult(), MatMatMultSymbolic()
7085 @*/
7086 PetscErrorCode PETSCMAT_DLLEXPORT MatMatMultNumeric(Mat A,Mat B,Mat C)
7087 {
7088   PetscErrorCode ierr;
7089   PetscErrorCode (*Anumeric)(Mat,Mat,Mat);
7090   PetscErrorCode (*Bnumeric)(Mat,Mat,Mat);
7091   PetscErrorCode (*numeric)(Mat,Mat,Mat)=PETSC_NULL;
7092 
7093   PetscFunctionBegin;
7094   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
7095   PetscValidType(A,1);
7096   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7097   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7098 
7099   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
7100   PetscValidType(B,2);
7101   MatPreallocated(B);
7102   if (!B->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7103   if (B->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7104 
7105   PetscValidHeaderSpecific(C,MAT_COOKIE,3);
7106   PetscValidType(C,3);
7107   MatPreallocated(C);
7108   if (!C->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7109   if (C->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7110 
7111   if (B->cmap.N!=C->cmap.N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",B->cmap.N,C->cmap.N);
7112   if (B->rmap.N!=A->cmap.N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",B->rmap.N,A->cmap.N);
7113   if (A->rmap.N!=C->rmap.N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",A->rmap.N,C->rmap.N);
7114   ierr = MatPreallocated(A);CHKERRQ(ierr);
7115 
7116   Anumeric = A->ops->matmultnumeric;
7117   Bnumeric = B->ops->matmultnumeric;
7118   if (Anumeric == Bnumeric){
7119     if (!Bnumeric) SETERRQ1(PETSC_ERR_SUP,"MatMatMultNumeric not supported for B of type %s",((PetscObject)B)->type_name);
7120     numeric = Bnumeric;
7121   } else {
7122     char  numericname[256];
7123     ierr = PetscStrcpy(numericname,"MatMatMultNumeric_");CHKERRQ(ierr);
7124     ierr = PetscStrcat(numericname,((PetscObject)A)->type_name);CHKERRQ(ierr);
7125     ierr = PetscStrcat(numericname,"_");CHKERRQ(ierr);
7126     ierr = PetscStrcat(numericname,((PetscObject)B)->type_name);CHKERRQ(ierr);
7127     ierr = PetscStrcat(numericname,"_C");CHKERRQ(ierr);
7128     ierr = PetscObjectQueryFunction((PetscObject)B,numericname,(void (**)(void))&numeric);CHKERRQ(ierr);
7129     if (!numeric)
7130       SETERRQ2(PETSC_ERR_ARG_INCOMP,"MatMatMultNumeric requires A, %s, to be compatible with B, %s",((PetscObject)A)->type_name,((PetscObject)B)->type_name);
7131   }
7132   ierr = PetscLogEventBegin(MAT_MatMultNumeric,A,B,0,0);CHKERRQ(ierr);
7133   ierr = (*numeric)(A,B,C);CHKERRQ(ierr);
7134   ierr = PetscLogEventEnd(MAT_MatMultNumeric,A,B,0,0);CHKERRQ(ierr);
7135   PetscFunctionReturn(0);
7136 }
7137 
7138 #undef __FUNCT__
7139 #define __FUNCT__ "MatMatMultTranspose"
7140 /*@
7141    MatMatMultTranspose - Performs Matrix-Matrix Multiplication C=A^T*B.
7142 
7143    Collective on Mat
7144 
7145    Input Parameters:
7146 +  A - the left matrix
7147 .  B - the right matrix
7148 .  scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
7149 -  fill - expected fill as ratio of nnz(C)/(nnz(A) + nnz(B))
7150 
7151    Output Parameters:
7152 .  C - the product matrix
7153 
7154    Notes:
7155    C will be created and must be destroyed by the user with MatDestroy().
7156 
7157    This routine is currently only implemented for pairs of SeqAIJ matrices and pairs of SeqDense matrices and classes
7158    which inherit from SeqAIJ.  C will be of type MATSEQAIJ.
7159 
7160    Level: intermediate
7161 
7162 .seealso: MatMatMultTransposeSymbolic(), MatMatMultTransposeNumeric(), MatPtAP()
7163 @*/
7164 PetscErrorCode PETSCMAT_DLLEXPORT MatMatMultTranspose(Mat A,Mat B,MatReuse scall,PetscReal fill,Mat *C)
7165 {
7166   PetscErrorCode ierr;
7167   PetscErrorCode (*fA)(Mat,Mat,MatReuse,PetscReal,Mat*);
7168   PetscErrorCode (*fB)(Mat,Mat,MatReuse,PetscReal,Mat*);
7169 
7170   PetscFunctionBegin;
7171   PetscValidHeaderSpecific(A,MAT_COOKIE,1);
7172   PetscValidType(A,1);
7173   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7174   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7175   PetscValidHeaderSpecific(B,MAT_COOKIE,2);
7176   PetscValidType(B,2);
7177   MatPreallocated(B);
7178   if (!B->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7179   if (B->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7180   PetscValidPointer(C,3);
7181   if (B->rmap.N!=A->rmap.N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Matrix dimensions are incompatible, %D != %D",B->rmap.N,A->rmap.N);
7182   if (fill < 1.0) SETERRQ1(PETSC_ERR_ARG_SIZ,"Expected fill=%G must be > 1.0",fill);
7183   ierr = MatPreallocated(A);CHKERRQ(ierr);
7184 
7185   fA = A->ops->matmulttranspose;
7186   if (!fA) SETERRQ1(PETSC_ERR_SUP,"MatMatMultTranspose not supported for A of type %s",((PetscObject)A)->type_name);
7187   fB = B->ops->matmulttranspose;
7188   if (!fB) SETERRQ1(PETSC_ERR_SUP,"MatMatMultTranspose not supported for B of type %s",((PetscObject)B)->type_name);
7189   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);
7190 
7191   ierr = PetscLogEventBegin(MAT_MatMultTranspose,A,B,0,0);CHKERRQ(ierr);
7192   ierr = (*A->ops->matmulttranspose)(A,B,scall,fill,C);CHKERRQ(ierr);
7193   ierr = PetscLogEventEnd(MAT_MatMultTranspose,A,B,0,0);CHKERRQ(ierr);
7194 
7195   PetscFunctionReturn(0);
7196 }
7197 
7198 #undef __FUNCT__
7199 #define __FUNCT__ "MatGetRedundantMatrix"
7200 /*@C
7201    MatGetRedundantMatrix - Create redundant matrices and put them into processors of subcommunicators.
7202 
7203    Collective on Mat
7204 
7205    Input Parameters:
7206 +  mat - the matrix
7207 .  nsubcomm - the number of subcommunicators (= number of redundant pareallel or sequential matrices)
7208 .  subcomm - MPI communicator split from the communicator where mat resides in
7209 .  mlocal_red - number of local rows of the redundant matrix
7210 -  reuse - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
7211 
7212    Output Parameter:
7213 .  matredundant - redundant matrix
7214 
7215    Notes:
7216    MAT_REUSE_MATRIX can only be used when the nonzero structure of the
7217    original matrix has not changed from that last call to MatGetRedundantMatrix().
7218 
7219    This routine creates the duplicated matrices in subcommunicators; you should NOT create them before
7220    calling it.
7221 
7222    Only MPIAIJ matrix is supported.
7223 
7224    Level: advanced
7225 
7226    Concepts: subcommunicator
7227    Concepts: duplicate matrix
7228 
7229 .seealso: MatDestroy()
7230 @*/
7231 PetscErrorCode PETSCMAT_DLLEXPORT MatGetRedundantMatrix(Mat mat,PetscInt nsubcomm,MPI_Comm subcomm,PetscInt mlocal_red,MatReuse reuse,Mat *matredundant)
7232 {
7233   PetscErrorCode ierr;
7234 
7235   PetscFunctionBegin;
7236   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
7237   if (nsubcomm && reuse == MAT_REUSE_MATRIX) {
7238     PetscValidPointer(*matredundant,6);
7239     PetscValidHeaderSpecific(*matredundant,MAT_COOKIE,6);
7240   }
7241   if (!mat->ops->getredundantmatrix) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
7242   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
7243   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
7244   ierr = MatPreallocated(mat);CHKERRQ(ierr);
7245 
7246   ierr = PetscLogEventBegin(MAT_GetRedundantMatrix,mat,0,0,0);CHKERRQ(ierr);
7247   ierr = (*mat->ops->getredundantmatrix)(mat,nsubcomm,subcomm,mlocal_red,reuse,matredundant);CHKERRQ(ierr);
7248   ierr = PetscLogEventEnd(MAT_GetRedundantMatrix,mat,0,0,0);CHKERRQ(ierr);
7249   PetscFunctionReturn(0);
7250 }
7251