xref: /petsc/src/mat/impls/shell/shell.c (revision 38f2d2fdb3b6f522a3102c6eb796cebecf3224c0)
1 #define PETSCMAT_DLL
2 
3 /*
4    This provides a simple shell for Fortran (and C programmers) to
5   create a very simple matrix class for use with KSP without coding
6   much of anything.
7 */
8 
9 #include "include/private/matimpl.h"        /*I "petscmat.h" I*/
10 #include "private/vecimpl.h"
11 
12 typedef struct {
13   PetscErrorCode (*destroy)(Mat);
14   PetscErrorCode (*mult)(Mat,Vec,Vec);
15   PetscErrorCode (*multtranspose)(Mat,Vec,Vec);
16   PetscErrorCode (*getdiagonal)(Mat,Vec);
17   PetscTruth     scale,shift;
18   PetscScalar    vscale,vshift;
19   void           *ctx;
20 } Mat_Shell;
21 
22 #undef __FUNCT__
23 #define __FUNCT__ "MatShellGetContext"
24 /*@
25     MatShellGetContext - Returns the user-provided context associated with a shell matrix.
26 
27     Not Collective
28 
29     Input Parameter:
30 .   mat - the matrix, should have been created with MatCreateShell()
31 
32     Output Parameter:
33 .   ctx - the user provided context
34 
35     Level: advanced
36 
37     Notes:
38     This routine is intended for use within various shell matrix routines,
39     as set with MatShellSetOperation().
40 
41 .keywords: matrix, shell, get, context
42 
43 .seealso: MatCreateShell(), MatShellSetOperation(), MatShellSetContext()
44 @*/
45 PetscErrorCode PETSCMAT_DLLEXPORT MatShellGetContext(Mat mat,void **ctx)
46 {
47   PetscErrorCode ierr;
48   PetscTruth     flg;
49 
50   PetscFunctionBegin;
51   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
52   PetscValidPointer(ctx,2);
53   ierr = PetscTypeCompare((PetscObject)mat,MATSHELL,&flg);CHKERRQ(ierr);
54   if (!flg) *ctx = 0;
55   else      *ctx = ((Mat_Shell*)(mat->data))->ctx;
56   PetscFunctionReturn(0);
57 }
58 
59 #undef __FUNCT__
60 #define __FUNCT__ "MatDestroy_Shell"
61 PetscErrorCode MatDestroy_Shell(Mat mat)
62 {
63   PetscErrorCode ierr;
64   Mat_Shell      *shell;
65 
66   PetscFunctionBegin;
67   shell = (Mat_Shell*)mat->data;
68   if (shell->destroy) {ierr = (*shell->destroy)(mat);CHKERRQ(ierr);}
69   ierr = PetscFree(shell);CHKERRQ(ierr);
70   PetscFunctionReturn(0);
71 }
72 
73 #undef __FUNCT__
74 #define __FUNCT__ "MatMult_Shell"
75 PetscErrorCode MatMult_Shell(Mat A,Vec x,Vec y)
76 {
77   Mat_Shell      *shell = (Mat_Shell*)A->data;
78   PetscErrorCode ierr;
79 
80   PetscFunctionBegin;
81   ierr = (*shell->mult)(A,x,y);CHKERRQ(ierr);
82   if (shell->shift && shell->scale) {
83     ierr = VecAXPBY(y,shell->vshift,shell->vscale,x);CHKERRQ(ierr);
84   } else if (shell->scale) {
85     ierr = VecScale(y,shell->vscale);CHKERRQ(ierr);
86   } else {
87     ierr = VecAXPY(y,shell->vshift,x);CHKERRQ(ierr);
88   }
89   PetscFunctionReturn(0);
90 }
91 
92 #undef __FUNCT__
93 #define __FUNCT__ "MatMultTranspose_Shell"
94 PetscErrorCode MatMultTranspose_Shell(Mat A,Vec x,Vec y)
95 {
96   Mat_Shell      *shell = (Mat_Shell*)A->data;
97   PetscErrorCode ierr;
98 
99   PetscFunctionBegin;
100   ierr = (*shell->multtranspose)(A,x,y);CHKERRQ(ierr);
101   if (shell->shift && shell->scale) {
102     ierr = VecAXPBY(y,shell->vshift,shell->vscale,x);CHKERRQ(ierr);
103   } else if (shell->scale) {
104     ierr = VecScale(y,shell->vscale);CHKERRQ(ierr);
105   } else {
106     ierr = VecAXPY(y,shell->vshift,x);CHKERRQ(ierr);
107   }
108   PetscFunctionReturn(0);
109 }
110 
111 #undef __FUNCT__
112 #define __FUNCT__ "MatGetDiagonal_Shell"
113 PetscErrorCode MatGetDiagonal_Shell(Mat A,Vec v)
114 {
115   Mat_Shell      *shell = (Mat_Shell*)A->data;
116   PetscErrorCode ierr;
117 
118   PetscFunctionBegin;
119   ierr = (*shell->getdiagonal)(A,v);CHKERRQ(ierr);
120   if (shell->scale) {
121     ierr = VecScale(v,shell->vscale);CHKERRQ(ierr);
122   }
123   if (shell->shift) {
124     ierr = VecShift(v,shell->vshift);CHKERRQ(ierr);
125   }
126   PetscFunctionReturn(0);
127 }
128 
129 #undef __FUNCT__
130 #define __FUNCT__ "MatShift_Shell"
131 PetscErrorCode MatShift_Shell(Mat Y,PetscScalar a)
132 {
133   Mat_Shell *shell = (Mat_Shell*)Y->data;
134 
135   PetscFunctionBegin;
136   if (shell->scale || shell->shift) {
137     shell->vshift += a;
138   } else {
139     shell->mult  = Y->ops->mult;
140     Y->ops->mult = MatMult_Shell;
141     if (Y->ops->multtranspose) {
142       shell->multtranspose  = Y->ops->multtranspose;
143       Y->ops->multtranspose = MatMultTranspose_Shell;
144     }
145     if (Y->ops->getdiagonal) {
146       shell->getdiagonal  = Y->ops->getdiagonal;
147       Y->ops->getdiagonal = MatGetDiagonal_Shell;
148     }
149     shell->vshift = a;
150   }
151   shell->shift  =  PETSC_TRUE;
152   PetscFunctionReturn(0);
153 }
154 
155 #undef __FUNCT__
156 #define __FUNCT__ "MatScale_Shell"
157 PetscErrorCode MatScale_Shell(Mat Y,PetscScalar a)
158 {
159   Mat_Shell *shell = (Mat_Shell*)Y->data;
160 
161   PetscFunctionBegin;
162   if (shell->scale || shell->shift) {
163     shell->vscale *= a;
164   } else {
165     shell->mult  = Y->ops->mult;
166     Y->ops->mult = MatMult_Shell;
167     if (Y->ops->multtranspose) {
168       shell->multtranspose  = Y->ops->multtranspose;
169       Y->ops->multtranspose = MatMultTranspose_Shell;
170     }
171     if (Y->ops->getdiagonal) {
172       shell->getdiagonal  = Y->ops->getdiagonal;
173       Y->ops->getdiagonal = MatGetDiagonal_Shell;
174     }
175     shell->vscale = a;
176   }
177   shell->scale  =  PETSC_TRUE;
178   PetscFunctionReturn(0);
179 }
180 
181 #undef __FUNCT__
182 #define __FUNCT__ "MatAssemblyEnd_Shell"
183 PetscErrorCode MatAssemblyEnd_Shell(Mat Y,MatAssemblyType t)
184 {
185   Mat_Shell *shell = (Mat_Shell*)Y->data;
186 
187   PetscFunctionBegin;
188   if ((shell->shift || shell->scale) && t == MAT_FINAL_ASSEMBLY) {
189     shell->scale  = PETSC_FALSE;
190     shell->shift  = PETSC_FALSE;
191     shell->vshift = 0.0;
192     shell->vscale = 1.0;
193     Y->ops->mult          = shell->mult;
194     Y->ops->multtranspose = shell->multtranspose;
195     Y->ops->getdiagonal   = shell->getdiagonal;
196   }
197   PetscFunctionReturn(0);
198 }
199 
200 EXTERN PetscErrorCode MatConvert_Shell(Mat, MatType,MatReuse,Mat*);
201 
202 #undef __FUNCT__
203 #define __FUNCT__ "MatSetBlockSize_Shell"
204 PetscErrorCode MatSetBlockSize_Shell(Mat A,PetscInt bs)
205 {
206   PetscFunctionBegin;
207   PetscFunctionReturn(0);
208 }
209 
210 static struct _MatOps MatOps_Values = {0,
211        0,
212        0,
213        0,
214 /* 4*/ 0,
215        0,
216        0,
217        0,
218        0,
219        0,
220 /*10*/ 0,
221        0,
222        0,
223        0,
224        0,
225 /*15*/ 0,
226        0,
227        0,
228        0,
229        0,
230 /*20*/ 0,
231        MatAssemblyEnd_Shell,
232        0,
233        0,
234        0,
235 /*25*/ 0,
236        0,
237        0,
238        0,
239        0,
240 /*30*/ 0,
241        0,
242        0,
243        0,
244        0,
245 /*35*/ 0,
246        0,
247        0,
248        0,
249        0,
250 /*40*/ 0,
251        0,
252        0,
253        0,
254        0,
255 /*45*/ 0,
256        MatScale_Shell,
257        MatShift_Shell,
258        0,
259        0,
260 /*50*/ MatSetBlockSize_Shell,
261        0,
262        0,
263        0,
264        0,
265 /*55*/ 0,
266        0,
267        0,
268        0,
269        0,
270 /*60*/ 0,
271        MatDestroy_Shell,
272        0,
273        0,
274        0,
275 /*65*/ 0,
276        0,
277        0,
278        0,
279        0,
280 /*70*/ 0,
281        MatConvert_Shell,
282        0,
283        0,
284        0,
285 /*75*/ 0,
286        0,
287        0,
288        0,
289        0,
290 /*80*/ 0,
291        0,
292        0,
293        0,
294        0,
295 /*85*/ 0,
296        0,
297        0,
298        0,
299        0,
300 /*90*/ 0,
301        0,
302        0,
303        0,
304        0,
305 /*95*/ 0,
306        0,
307        0,
308        0};
309 
310 /*MC
311    MATSHELL - MATSHELL = "shell" - A matrix type to be used to define your own matrix type -- perhaps matrix free.
312 
313   Level: advanced
314 
315 .seealso: MatCreateShell
316 M*/
317 
318 EXTERN_C_BEGIN
319 #undef __FUNCT__
320 #define __FUNCT__ "MatCreate_Shell"
321 PetscErrorCode PETSCMAT_DLLEXPORT MatCreate_Shell(Mat A)
322 {
323   Mat_Shell      *b;
324   PetscErrorCode ierr;
325 
326   PetscFunctionBegin;
327   ierr = PetscMemcpy(A->ops,&MatOps_Values,sizeof(struct _MatOps));CHKERRQ(ierr);
328 
329   ierr = PetscNewLog(A,Mat_Shell,&b);CHKERRQ(ierr);
330   A->data = (void*)b;
331 
332   if (A->rmap.n == PETSC_DECIDE || A->cmap.n == PETSC_DECIDE) {
333     SETERRQ(PETSC_ERR_ARG_WRONG,"Must give local row and column count for matrix");
334   }
335 
336   ierr = PetscMapSetBlockSize(&A->rmap,1);CHKERRQ(ierr);
337   ierr = PetscMapSetBlockSize(&A->cmap,1);CHKERRQ(ierr);
338   ierr = PetscMapSetUp(&A->rmap);CHKERRQ(ierr);
339   ierr = PetscMapSetUp(&A->cmap);CHKERRQ(ierr);
340 
341   b->ctx           = 0;
342   b->scale         = PETSC_FALSE;
343   b->shift         = PETSC_FALSE;
344   b->vshift        = 0.0;
345   b->vscale        = 1.0;
346   b->mult          = 0;
347   b->multtranspose = 0;
348   b->getdiagonal   = 0;
349   A->assembled     = PETSC_TRUE;
350   A->preallocated  = PETSC_FALSE;
351   ierr = PetscObjectChangeTypeName((PetscObject)A,MATSHELL);CHKERRQ(ierr);
352   PetscFunctionReturn(0);
353 }
354 EXTERN_C_END
355 
356 #undef __FUNCT__
357 #define __FUNCT__ "MatCreateShell"
358 /*@C
359    MatCreateShell - Creates a new matrix class for use with a user-defined
360    private data storage format.
361 
362   Collective on MPI_Comm
363 
364    Input Parameters:
365 +  comm - MPI communicator
366 .  m - number of local rows (must be given)
367 .  n - number of local columns (must be given)
368 .  M - number of global rows (may be PETSC_DETERMINE)
369 .  N - number of global columns (may be PETSC_DETERMINE)
370 -  ctx - pointer to data needed by the shell matrix routines
371 
372    Output Parameter:
373 .  A - the matrix
374 
375    Level: advanced
376 
377   Usage:
378 $    extern int mult(Mat,Vec,Vec);
379 $    MatCreateShell(comm,m,n,M,N,ctx,&mat);
380 $    MatShellSetOperation(mat,MATOP_MULT,(void(*)(void))mult);
381 $    [ Use matrix for operations that have been set ]
382 $    MatDestroy(mat);
383 
384    Notes:
385    The shell matrix type is intended to provide a simple class to use
386    with KSP (such as, for use with matrix-free methods). You should not
387    use the shell type if you plan to define a complete matrix class.
388 
389    Fortran Notes: The context can only be an integer or a PetscObject
390       unfortunately it cannot be a Fortran array or derived type.
391 
392    PETSc requires that matrices and vectors being used for certain
393    operations are partitioned accordingly.  For example, when
394    creating a shell matrix, A, that supports parallel matrix-vector
395    products using MatMult(A,x,y) the user should set the number
396    of local matrix rows to be the number of local elements of the
397    corresponding result vector, y. Note that this is information is
398    required for use of the matrix interface routines, even though
399    the shell matrix may not actually be physically partitioned.
400    For example,
401 
402 $
403 $     Vec x, y
404 $     extern int mult(Mat,Vec,Vec);
405 $     Mat A
406 $
407 $     VecCreateMPI(comm,PETSC_DECIDE,M,&y);
408 $     VecCreateMPI(comm,PETSC_DECIDE,N,&x);
409 $     VecGetLocalSize(y,&m);
410 $     VecGetLocalSize(x,&n);
411 $     MatCreateShell(comm,m,n,M,N,ctx,&A);
412 $     MatShellSetOperation(mat,MATOP_MULT,(void(*)(void))mult);
413 $     MatMult(A,x,y);
414 $     MatDestroy(A);
415 $     VecDestroy(y); VecDestroy(x);
416 $
417 
418 .keywords: matrix, shell, create
419 
420 .seealso: MatShellSetOperation(), MatHasOperation(), MatShellGetContext(), MatShellSetContext()
421 @*/
422 PetscErrorCode PETSCMAT_DLLEXPORT MatCreateShell(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt M,PetscInt N,void *ctx,Mat *A)
423 {
424   PetscErrorCode ierr;
425 
426   PetscFunctionBegin;
427   ierr = MatCreate(comm,A);CHKERRQ(ierr);
428   ierr = MatSetSizes(*A,m,n,M,N);CHKERRQ(ierr);
429 
430   ierr = MatSetType(*A,MATSHELL);CHKERRQ(ierr);
431   ierr = MatShellSetContext(*A,ctx);CHKERRQ(ierr);
432   PetscFunctionReturn(0);
433 }
434 
435 #undef __FUNCT__
436 #define __FUNCT__ "MatShellSetContext"
437 /*@
438     MatShellSetContext - sets the context for a shell matrix
439 
440    Collective on Mat
441 
442     Input Parameters:
443 +   mat - the shell matrix
444 -   ctx - the context
445 
446    Level: advanced
447 
448    Fortran Notes: The context can only be an integer or a PetscObject
449       unfortunately it cannot be a Fortran array or derived type.
450 
451 .seealso: MatCreateShell(), MatShellGetContext(), MatShellGetOperation()
452 @*/
453 PetscErrorCode PETSCMAT_DLLEXPORT MatShellSetContext(Mat mat,void *ctx)
454 {
455   Mat_Shell      *shell = (Mat_Shell*)mat->data;
456   PetscErrorCode ierr;
457   PetscTruth     flg;
458 
459   PetscFunctionBegin;
460   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
461   ierr = PetscTypeCompare((PetscObject)mat,MATSHELL,&flg);CHKERRQ(ierr);
462   if (flg) {
463     shell->ctx = ctx;
464   }
465   PetscFunctionReturn(0);
466 }
467 
468 #undef __FUNCT__
469 #define __FUNCT__ "MatShellSetOperation"
470 /*@C
471     MatShellSetOperation - Allows user to set a matrix operation for
472                            a shell matrix.
473 
474    Collective on Mat
475 
476     Input Parameters:
477 +   mat - the shell matrix
478 .   op - the name of the operation
479 -   f - the function that provides the operation.
480 
481    Level: advanced
482 
483     Usage:
484 $      extern PetscErrorCode usermult(Mat,Vec,Vec);
485 $      ierr = MatCreateShell(comm,m,n,M,N,ctx,&A);
486 $      ierr = MatShellSetOperation(A,MATOP_MULT,(void(*)(void))usermult);
487 
488     Notes:
489     See the file include/petscmat.h for a complete list of matrix
490     operations, which all have the form MATOP_<OPERATION>, where
491     <OPERATION> is the name (in all capital letters) of the
492     user interface routine (e.g., MatMult() -> MATOP_MULT).
493 
494     All user-provided functions should have the same calling
495     sequence as the usual matrix interface routines, since they
496     are intended to be accessed via the usual matrix interface
497     routines, e.g.,
498 $       MatMult(Mat,Vec,Vec) -> usermult(Mat,Vec,Vec)
499 
500     Within each user-defined routine, the user should call
501     MatShellGetContext() to obtain the user-defined context that was
502     set by MatCreateShell().
503 
504 .keywords: matrix, shell, set, operation
505 
506 .seealso: MatCreateShell(), MatShellGetContext(), MatShellGetOperation(), MatShellSetContext()
507 @*/
508 PetscErrorCode PETSCMAT_DLLEXPORT MatShellSetOperation(Mat mat,MatOperation op,void (*f)(void))
509 {
510   PetscErrorCode ierr;
511   PetscTruth     flg;
512 
513   PetscFunctionBegin;
514   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
515   if (op == MATOP_DESTROY) {
516     ierr = PetscTypeCompare((PetscObject)mat,MATSHELL,&flg);CHKERRQ(ierr);
517     if (flg) {
518        Mat_Shell *shell = (Mat_Shell*)mat->data;
519        shell->destroy                 = (PetscErrorCode (*)(Mat)) f;
520     } else mat->ops->destroy          = (PetscErrorCode (*)(Mat)) f;
521   }
522   else if (op == MATOP_VIEW) mat->ops->view  = (PetscErrorCode (*)(Mat,PetscViewer)) f;
523   else                       (((void(**)(void))mat->ops)[op]) = f;
524 
525   PetscFunctionReturn(0);
526 }
527 
528 #undef __FUNCT__
529 #define __FUNCT__ "MatShellGetOperation"
530 /*@C
531     MatShellGetOperation - Gets a matrix function for a shell matrix.
532 
533     Not Collective
534 
535     Input Parameters:
536 +   mat - the shell matrix
537 -   op - the name of the operation
538 
539     Output Parameter:
540 .   f - the function that provides the operation.
541 
542     Level: advanced
543 
544     Notes:
545     See the file include/petscmat.h for a complete list of matrix
546     operations, which all have the form MATOP_<OPERATION>, where
547     <OPERATION> is the name (in all capital letters) of the
548     user interface routine (e.g., MatMult() -> MATOP_MULT).
549 
550     All user-provided functions have the same calling
551     sequence as the usual matrix interface routines, since they
552     are intended to be accessed via the usual matrix interface
553     routines, e.g.,
554 $       MatMult(Mat,Vec,Vec) -> usermult(Mat,Vec,Vec)
555 
556     Within each user-defined routine, the user should call
557     MatShellGetContext() to obtain the user-defined context that was
558     set by MatCreateShell().
559 
560 .keywords: matrix, shell, set, operation
561 
562 .seealso: MatCreateShell(), MatShellGetContext(), MatShellSetOperation(), MatShellSetContext()
563 @*/
564 PetscErrorCode PETSCMAT_DLLEXPORT MatShellGetOperation(Mat mat,MatOperation op,void(**f)(void))
565 {
566   PetscErrorCode ierr;
567   PetscTruth     flg;
568 
569   PetscFunctionBegin;
570   PetscValidHeaderSpecific(mat,MAT_COOKIE,1);
571   if (op == MATOP_DESTROY) {
572     ierr = PetscTypeCompare((PetscObject)mat,MATSHELL,&flg);CHKERRQ(ierr);
573     if (flg) {
574       Mat_Shell *shell = (Mat_Shell*)mat->data;
575       *f = (void(*)(void))shell->destroy;
576     } else {
577       *f = (void(*)(void))mat->ops->destroy;
578     }
579   } else if (op == MATOP_VIEW) {
580     *f = (void(*)(void))mat->ops->view;
581   } else {
582     *f = (((void(**)(void))mat->ops)[op]);
583   }
584 
585   PetscFunctionReturn(0);
586 }
587 
588