Actual source code: itcreate.c
1: /*
2: The basic KSP routines, Create, View etc. are here.
3: */
4: #include <petsc/private/kspimpl.h>
6: /* Logging support */
7: PetscClassId KSP_CLASSID;
8: PetscClassId DMKSP_CLASSID;
9: PetscClassId KSPGUESS_CLASSID;
10: PetscLogEvent KSP_GMRESOrthogonalization, KSP_SetUp, KSP_Solve, KSP_SolveTranspose, KSP_MatSolve;
12: /*
13: Contains the list of registered KSP routines
14: */
15: PetscFunctionList KSPList = NULL;
16: PetscBool KSPRegisterAllCalled = PETSC_FALSE;
18: /*
19: Contains the list of registered KSP monitors
20: */
21: PetscFunctionList KSPMonitorList = NULL;
22: PetscFunctionList KSPMonitorCreateList = NULL;
23: PetscFunctionList KSPMonitorDestroyList = NULL;
24: PetscBool KSPMonitorRegisterAllCalled = PETSC_FALSE;
26: /*@C
27: KSPLoad - Loads a KSP that has been stored in binary with KSPView().
29: Collective on viewer
31: Input Parameters:
32: + newdm - the newly loaded KSP, this needs to have been created with KSPCreate() or
33: some related function before a call to KSPLoad().
34: - viewer - binary file viewer, obtained from PetscViewerBinaryOpen()
36: Level: intermediate
38: Notes:
39: The type is determined by the data in the file, any type set into the KSP before this call is ignored.
41: Notes for advanced users:
42: Most users should not need to know the details of the binary storage
43: format, since KSPLoad() and KSPView() completely hide these details.
44: But for anyone who's interested, the standard binary matrix storage
45: format is
46: .vb
47: has not yet been determined
48: .ve
50: .seealso: PetscViewerBinaryOpen(), KSPView(), MatLoad(), VecLoad()
51: @*/
52: PetscErrorCode KSPLoad(KSP newdm, PetscViewer viewer)
53: {
54: PetscBool isbinary;
55: PetscInt classid;
56: char type[256];
57: PC pc;
61: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);
64: PetscViewerBinaryRead(viewer,&classid,1,NULL,PETSC_INT);
66: PetscViewerBinaryRead(viewer,type,256,NULL,PETSC_CHAR);
67: KSPSetType(newdm, type);
68: if (newdm->ops->load) (*newdm->ops->load)(newdm,viewer);
69: KSPGetPC(newdm,&pc);
70: PCLoad(pc,viewer);
71: return 0;
72: }
74: #include <petscdraw.h>
75: #if defined(PETSC_HAVE_SAWS)
76: #include <petscviewersaws.h>
77: #endif
78: /*@C
79: KSPView - Prints the KSP data structure.
81: Collective on ksp
83: Input Parameters:
84: + ksp - the Krylov space context
85: - viewer - visualization context
87: Options Database Keys:
88: . -ksp_view - print the KSP data structure at the end of a KSPSolve call
90: Note:
91: The available visualization contexts include
92: + PETSC_VIEWER_STDOUT_SELF - standard output (default)
93: - PETSC_VIEWER_STDOUT_WORLD - synchronized standard
94: output where only the first processor opens
95: the file. All other processors send their
96: data to the first processor to print.
98: The available formats include
99: + PETSC_VIEWER_DEFAULT - standard output (default)
100: - PETSC_VIEWER_ASCII_INFO_DETAIL - more verbose output for PCBJACOBI and PCASM
102: The user can open an alternative visualization context with
103: PetscViewerASCIIOpen() - output to a specified file.
105: In the debugger you can do "call KSPView(ksp,0)" to display the KSP. (The same holds for any PETSc object viewer).
107: Level: beginner
109: .seealso: PCView(), PetscViewerASCIIOpen()
110: @*/
111: PetscErrorCode KSPView(KSP ksp,PetscViewer viewer)
112: {
113: PetscBool iascii,isbinary,isdraw,isstring;
114: #if defined(PETSC_HAVE_SAWS)
115: PetscBool issaws;
116: #endif
119: if (!viewer) {
120: PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)ksp),&viewer);
121: }
125: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);
126: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);
127: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);
128: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSTRING,&isstring);
129: #if defined(PETSC_HAVE_SAWS)
130: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSAWS,&issaws);
131: #endif
132: if (iascii) {
133: PetscObjectPrintClassNamePrefixType((PetscObject)ksp,viewer);
134: if (ksp->ops->view) {
135: PetscViewerASCIIPushTab(viewer);
136: (*ksp->ops->view)(ksp,viewer);
137: PetscViewerASCIIPopTab(viewer);
138: }
139: if (ksp->guess_zero) {
140: PetscViewerASCIIPrintf(viewer," maximum iterations=%D, initial guess is zero\n",ksp->max_it);
141: } else {
142: PetscViewerASCIIPrintf(viewer," maximum iterations=%D, nonzero initial guess\n", ksp->max_it);
143: }
144: if (ksp->guess_knoll) PetscViewerASCIIPrintf(viewer," using preconditioner applied to right hand side for initial guess\n");
145: PetscViewerASCIIPrintf(viewer," tolerances: relative=%g, absolute=%g, divergence=%g\n",(double)ksp->rtol,(double)ksp->abstol,(double)ksp->divtol);
146: if (ksp->pc_side == PC_RIGHT) {
147: PetscViewerASCIIPrintf(viewer," right preconditioning\n");
148: } else if (ksp->pc_side == PC_SYMMETRIC) {
149: PetscViewerASCIIPrintf(viewer," symmetric preconditioning\n");
150: } else {
151: PetscViewerASCIIPrintf(viewer," left preconditioning\n");
152: }
153: if (ksp->guess) {
154: PetscViewerASCIIPushTab(viewer);
155: KSPGuessView(ksp->guess,viewer);
156: PetscViewerASCIIPopTab(viewer);
157: }
158: if (ksp->dscale) PetscViewerASCIIPrintf(viewer," diagonally scaled system\n");
159: PetscViewerASCIIPrintf(viewer," using %s norm type for convergence test\n",KSPNormTypes[ksp->normtype]);
160: } else if (isbinary) {
161: PetscInt classid = KSP_FILE_CLASSID;
162: MPI_Comm comm;
163: PetscMPIInt rank;
164: char type[256];
166: PetscObjectGetComm((PetscObject)ksp,&comm);
167: MPI_Comm_rank(comm,&rank);
168: if (rank == 0) {
169: PetscViewerBinaryWrite(viewer,&classid,1,PETSC_INT);
170: PetscStrncpy(type,((PetscObject)ksp)->type_name,256);
171: PetscViewerBinaryWrite(viewer,type,256,PETSC_CHAR);
172: }
173: if (ksp->ops->view) {
174: (*ksp->ops->view)(ksp,viewer);
175: }
176: } else if (isstring) {
177: const char *type;
178: KSPGetType(ksp,&type);
179: PetscViewerStringSPrintf(viewer," KSPType: %-7.7s",type);
180: if (ksp->ops->view) (*ksp->ops->view)(ksp,viewer);
181: } else if (isdraw) {
182: PetscDraw draw;
183: char str[36];
184: PetscReal x,y,bottom,h;
185: PetscBool flg;
187: PetscViewerDrawGetDraw(viewer,0,&draw);
188: PetscDrawGetCurrentPoint(draw,&x,&y);
189: PetscObjectTypeCompare((PetscObject)ksp,KSPPREONLY,&flg);
190: if (!flg) {
191: PetscStrncpy(str,"KSP: ",sizeof(str));
192: PetscStrlcat(str,((PetscObject)ksp)->type_name,sizeof(str));
193: PetscDrawStringBoxed(draw,x,y,PETSC_DRAW_RED,PETSC_DRAW_BLACK,str,NULL,&h);
194: bottom = y - h;
195: } else {
196: bottom = y;
197: }
198: PetscDrawPushCurrentPoint(draw,x,bottom);
199: #if defined(PETSC_HAVE_SAWS)
200: } else if (issaws) {
201: PetscMPIInt rank;
202: const char *name;
204: PetscObjectGetName((PetscObject)ksp,&name);
205: MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
206: if (!((PetscObject)ksp)->amsmem && rank == 0) {
207: char dir[1024];
209: PetscObjectViewSAWs((PetscObject)ksp,viewer);
210: PetscSNPrintf(dir,1024,"/PETSc/Objects/%s/its",name);
211: PetscStackCallSAWs(SAWs_Register,(dir,&ksp->its,1,SAWs_READ,SAWs_INT));
212: if (!ksp->res_hist) {
213: KSPSetResidualHistory(ksp,NULL,PETSC_DECIDE,PETSC_TRUE);
214: }
215: PetscSNPrintf(dir,1024,"/PETSc/Objects/%s/res_hist",name);
216: PetscStackCallSAWs(SAWs_Register,(dir,ksp->res_hist,10,SAWs_READ,SAWs_DOUBLE));
217: }
218: #endif
219: } else if (ksp->ops->view) {
220: (*ksp->ops->view)(ksp,viewer);
221: }
222: if (ksp->pc) {
223: PCView(ksp->pc,viewer);
224: }
225: if (isdraw) {
226: PetscDraw draw;
227: PetscViewerDrawGetDraw(viewer,0,&draw);
228: PetscDrawPopCurrentPoint(draw);
229: }
230: return 0;
231: }
233: /*@C
234: KSPViewFromOptions - View from Options
236: Collective on KSP
238: Input Parameters:
239: + A - Krylov solver context
240: . obj - Optional object
241: - name - command line option
243: Level: intermediate
244: .seealso: KSP, KSPView, PetscObjectViewFromOptions(), KSPCreate()
245: @*/
246: PetscErrorCode KSPViewFromOptions(KSP A,PetscObject obj,const char name[])
247: {
249: PetscObjectViewFromOptions((PetscObject)A,obj,name);
250: return 0;
251: }
253: /*@
254: KSPSetNormType - Sets the norm that is used for convergence testing.
256: Logically Collective on ksp
258: Input Parameters:
259: + ksp - Krylov solver context
260: - normtype - one of
261: $ KSP_NORM_NONE - skips computing the norm, this should generally only be used if you are using
262: $ the Krylov method as a smoother with a fixed small number of iterations.
263: $ Implicitly sets KSPConvergedSkip() as KSP convergence test.
264: $ Note that certain algorithms such as KSPGMRES ALWAYS require the norm calculation,
265: $ for these methods the norms are still computed, they are just not used in
266: $ the convergence test.
267: $ KSP_NORM_PRECONDITIONED - the default for left preconditioned solves, uses the l2 norm
268: $ of the preconditioned residual P^{-1}(b - A x)
269: $ KSP_NORM_UNPRECONDITIONED - uses the l2 norm of the true b - Ax residual.
270: $ KSP_NORM_NATURAL - supported by KSPCG, KSPCR, KSPCGNE, KSPCGS
272: Options Database Key:
273: . -ksp_norm_type <none,preconditioned,unpreconditioned,natural> - set KSP norm type
275: Notes:
276: Not all combinations of preconditioner side (see KSPSetPCSide()) and norm type are supported by all Krylov methods.
277: If only one is set, PETSc tries to automatically change the other to find a compatible pair. If no such combination
278: is supported, PETSc will generate an error.
280: Developer Notes:
281: Supported combinations of norm and preconditioner side are set using KSPSetSupportedNorm().
283: Level: advanced
285: .seealso: KSPSetUp(), KSPSolve(), KSPDestroy(), KSPConvergedSkip(), KSPSetCheckNormIteration(), KSPSetPCSide(), KSPGetPCSide(), KSPNormType
286: @*/
287: PetscErrorCode KSPSetNormType(KSP ksp,KSPNormType normtype)
288: {
291: ksp->normtype = ksp->normtype_set = normtype;
292: return 0;
293: }
295: /*@
296: KSPSetCheckNormIteration - Sets the first iteration at which the norm of the residual will be
297: computed and used in the convergence test.
299: Logically Collective on ksp
301: Input Parameters:
302: + ksp - Krylov solver context
303: - it - use -1 to check at all iterations
305: Notes:
306: Currently only works with KSPCG, KSPBCGS and KSPIBCGS
308: Use KSPSetNormType(ksp,KSP_NORM_NONE) to never check the norm
310: On steps where the norm is not computed, the previous norm is still in the variable, so if you run with, for example,
311: -ksp_monitor the residual norm will appear to be unchanged for several iterations (though it is not really unchanged).
312: Level: advanced
314: .seealso: KSPSetUp(), KSPSolve(), KSPDestroy(), KSPConvergedSkip(), KSPSetNormType()
315: @*/
316: PetscErrorCode KSPSetCheckNormIteration(KSP ksp,PetscInt it)
317: {
320: ksp->chknorm = it;
321: return 0;
322: }
324: /*@
325: KSPSetLagNorm - Lags the residual norm calculation so that it is computed as part of the MPI_Allreduce() for
326: computing the inner products for the next iteration. This can reduce communication costs at the expense of doing
327: one additional iteration.
329: Logically Collective on ksp
331: Input Parameters:
332: + ksp - Krylov solver context
333: - flg - PETSC_TRUE or PETSC_FALSE
335: Options Database Keys:
336: . -ksp_lag_norm - lag the calculated residual norm
338: Notes:
339: Currently only works with KSPIBCGS.
341: Use KSPSetNormType(ksp,KSP_NORM_NONE) to never check the norm
343: If you lag the norm and run with, for example, -ksp_monitor, the residual norm reported will be the lagged one.
344: Level: advanced
346: .seealso: KSPSetUp(), KSPSolve(), KSPDestroy(), KSPConvergedSkip(), KSPSetNormType(), KSPSetCheckNormIteration()
347: @*/
348: PetscErrorCode KSPSetLagNorm(KSP ksp,PetscBool flg)
349: {
352: ksp->lagnorm = flg;
353: return 0;
354: }
356: /*@
357: KSPSetSupportedNorm - Sets a norm and preconditioner side supported by a KSP
359: Logically Collective
361: Input Parameters:
362: + ksp - Krylov method
363: . normtype - supported norm type
364: . pcside - preconditioner side that can be used with this norm
365: - priority - positive integer preference for this combination; larger values have higher priority
367: Level: developer
369: Notes:
370: This function should be called from the implementation files KSPCreate_XXX() to declare
371: which norms and preconditioner sides are supported. Users should not need to call this
372: function.
374: .seealso: KSPSetNormType(), KSPSetPCSide()
375: @*/
376: PetscErrorCode KSPSetSupportedNorm(KSP ksp,KSPNormType normtype,PCSide pcside,PetscInt priority)
377: {
379: ksp->normsupporttable[normtype][pcside] = priority;
380: return 0;
381: }
383: PetscErrorCode KSPNormSupportTableReset_Private(KSP ksp)
384: {
385: PetscMemzero(ksp->normsupporttable,sizeof(ksp->normsupporttable));
386: ksp->pc_side = ksp->pc_side_set;
387: ksp->normtype = ksp->normtype_set;
388: return 0;
389: }
391: PetscErrorCode KSPSetUpNorms_Private(KSP ksp,PetscBool errorifnotsupported,KSPNormType *normtype,PCSide *pcside)
392: {
393: PetscInt i,j,best,ibest = 0,jbest = 0;
395: best = 0;
396: for (i=0; i<KSP_NORM_MAX; i++) {
397: for (j=0; j<PC_SIDE_MAX; j++) {
398: if ((ksp->normtype == KSP_NORM_DEFAULT || ksp->normtype == i) && (ksp->pc_side == PC_SIDE_DEFAULT || ksp->pc_side == j) && (ksp->normsupporttable[i][j] > best)) {
399: best = ksp->normsupporttable[i][j];
400: ibest = i;
401: jbest = j;
402: }
403: }
404: }
405: if (best < 1 && errorifnotsupported) {
409: SETERRQ(PetscObjectComm((PetscObject)ksp),PETSC_ERR_SUP,"KSP %s does not support %s with %s",((PetscObject)ksp)->type_name,KSPNormTypes[ksp->normtype],PCSides[ksp->pc_side]);
410: }
411: if (normtype) *normtype = (KSPNormType)ibest;
412: if (pcside) *pcside = (PCSide)jbest;
413: return 0;
414: }
416: /*@
417: KSPGetNormType - Gets the norm that is used for convergence testing.
419: Not Collective
421: Input Parameter:
422: . ksp - Krylov solver context
424: Output Parameter:
425: . normtype - norm that is used for convergence testing
427: Level: advanced
429: .seealso: KSPNormType, KSPSetNormType(), KSPConvergedSkip()
430: @*/
431: PetscErrorCode KSPGetNormType(KSP ksp, KSPNormType *normtype)
432: {
435: KSPSetUpNorms_Private(ksp,PETSC_TRUE,&ksp->normtype,&ksp->pc_side);
436: *normtype = ksp->normtype;
437: return 0;
438: }
440: #if defined(PETSC_HAVE_SAWS)
441: #include <petscviewersaws.h>
442: #endif
444: /*@
445: KSPSetOperators - Sets the matrix associated with the linear system
446: and a (possibly) different one associated with the preconditioner.
448: Collective on ksp
450: Input Parameters:
451: + ksp - the KSP context
452: . Amat - the matrix that defines the linear system
453: - Pmat - the matrix to be used in constructing the preconditioner, usually the same as Amat.
455: Notes:
457: If you know the operator Amat has a null space you can use MatSetNullSpace() and MatSetTransposeNullSpace() to supply the null
458: space to Amat and the KSP solvers will automatically use that null space as needed during the solution process.
460: All future calls to KSPSetOperators() must use the same size matrices!
462: Passing a NULL for Amat or Pmat removes the matrix that is currently used.
464: If you wish to replace either Amat or Pmat but leave the other one untouched then
465: first call KSPGetOperators() to get the one you wish to keep, call PetscObjectReference()
466: on it and then pass it back in in your call to KSPSetOperators().
468: Level: beginner
470: Alternative usage: If the operators have NOT been set with KSP/PCSetOperators() then the operators
471: are created in PC and returned to the user. In this case, if both operators
472: mat and pmat are requested, two DIFFERENT operators will be returned. If
473: only one is requested both operators in the PC will be the same (i.e. as
474: if one had called KSP/PCSetOperators() with the same argument for both Mats).
475: The user must set the sizes of the returned matrices and their type etc just
476: as if the user created them with MatCreate(). For example,
478: $ KSP/PCGetOperators(ksp/pc,&mat,NULL); is equivalent to
479: $ set size, type, etc of mat
481: $ MatCreate(comm,&mat);
482: $ KSP/PCSetOperators(ksp/pc,mat,mat);
483: $ PetscObjectDereference((PetscObject)mat);
484: $ set size, type, etc of mat
486: and
488: $ KSP/PCGetOperators(ksp/pc,&mat,&pmat); is equivalent to
489: $ set size, type, etc of mat and pmat
491: $ MatCreate(comm,&mat);
492: $ MatCreate(comm,&pmat);
493: $ KSP/PCSetOperators(ksp/pc,mat,pmat);
494: $ PetscObjectDereference((PetscObject)mat);
495: $ PetscObjectDereference((PetscObject)pmat);
496: $ set size, type, etc of mat and pmat
498: The rational for this support is so that when creating a TS, SNES, or KSP the hierarchy
499: of underlying objects (i.e. SNES, KSP, PC, Mat) and their livespans can be completely
500: managed by the top most level object (i.e. the TS, SNES, or KSP). Another way to look
501: at this is when you create a SNES you do not NEED to create a KSP and attach it to
502: the SNES object (the SNES object manages it for you). Similarly when you create a KSP
503: you do not need to attach a PC to it (the KSP object manages the PC object for you).
504: Thus, why should YOU have to create the Mat and attach it to the SNES/KSP/PC, when
505: it can be created for you?
507: .seealso: KSPSolve(), KSPGetPC(), PCGetOperators(), PCSetOperators(), KSPGetOperators(), KSPSetComputeOperators(), KSPSetComputeInitialGuess(), KSPSetComputeRHS()
508: @*/
509: PetscErrorCode KSPSetOperators(KSP ksp,Mat Amat,Mat Pmat)
510: {
516: if (!ksp->pc) KSPGetPC(ksp,&ksp->pc);
517: PCSetOperators(ksp->pc,Amat,Pmat);
518: if (ksp->setupstage == KSP_SETUP_NEWRHS) ksp->setupstage = KSP_SETUP_NEWMATRIX; /* so that next solve call will call PCSetUp() on new matrix */
519: return 0;
520: }
522: /*@
523: KSPGetOperators - Gets the matrix associated with the linear system
524: and a (possibly) different one associated with the preconditioner.
526: Collective on ksp
528: Input Parameter:
529: . ksp - the KSP context
531: Output Parameters:
532: + Amat - the matrix that defines the linear system
533: - Pmat - the matrix to be used in constructing the preconditioner, usually the same as Amat.
535: Level: intermediate
537: Notes:
538: DOES NOT increase the reference counts of the matrix, so you should NOT destroy them.
540: .seealso: KSPSolve(), KSPGetPC(), PCGetOperators(), PCSetOperators(), KSPSetOperators(), KSPGetOperatorsSet()
541: @*/
542: PetscErrorCode KSPGetOperators(KSP ksp,Mat *Amat,Mat *Pmat)
543: {
545: if (!ksp->pc) KSPGetPC(ksp,&ksp->pc);
546: PCGetOperators(ksp->pc,Amat,Pmat);
547: return 0;
548: }
550: /*@C
551: KSPGetOperatorsSet - Determines if the matrix associated with the linear system and
552: possibly a different one associated with the preconditioner have been set in the KSP.
554: Not collective, though the results on all processes should be the same
556: Input Parameter:
557: . pc - the KSP context
559: Output Parameters:
560: + mat - the matrix associated with the linear system was set
561: - pmat - matrix associated with the preconditioner was set, usually the same
563: Level: intermediate
565: .seealso: PCSetOperators(), KSPGetOperators(), KSPSetOperators(), PCGetOperators(), PCGetOperatorsSet()
566: @*/
567: PetscErrorCode KSPGetOperatorsSet(KSP ksp,PetscBool *mat,PetscBool *pmat)
568: {
570: if (!ksp->pc) KSPGetPC(ksp,&ksp->pc);
571: PCGetOperatorsSet(ksp->pc,mat,pmat);
572: return 0;
573: }
575: /*@C
576: KSPSetPreSolve - Sets a function that is called before every KSPSolve() is started
578: Logically Collective on ksp
580: Input Parameters:
581: + ksp - the solver object
582: . presolve - the function to call before the solve
583: - prectx - any context needed by the function
585: Calling sequence of presolve:
586: $ func(KSP ksp,Vec rhs,Vec x,void *ctx)
588: + ksp - the KSP context
589: . rhs - the right-hand side vector
590: . x - the solution vector
591: - ctx - optional user-provided context
593: Level: developer
595: .seealso: KSPSetUp(), KSPSolve(), KSPDestroy(), KSP, KSPSetPostSolve()
596: @*/
597: PetscErrorCode KSPSetPreSolve(KSP ksp,PetscErrorCode (*presolve)(KSP,Vec,Vec,void*),void *prectx)
598: {
600: ksp->presolve = presolve;
601: ksp->prectx = prectx;
602: return 0;
603: }
605: /*@C
606: KSPSetPostSolve - Sets a function that is called after every KSPSolve() completes (whether it converges or not)
608: Logically Collective on ksp
610: Input Parameters:
611: + ksp - the solver object
612: . postsolve - the function to call after the solve
613: - postctx - any context needed by the function
615: Level: developer
617: Calling sequence of postsolve:
618: $ func(KSP ksp,Vec rhs,Vec x,void *ctx)
620: + ksp - the KSP context
621: . rhs - the right-hand side vector
622: . x - the solution vector
623: - ctx - optional user-provided context
625: .seealso: KSPSetUp(), KSPSolve(), KSPDestroy(), KSP, KSPSetPreSolve()
626: @*/
627: PetscErrorCode KSPSetPostSolve(KSP ksp,PetscErrorCode (*postsolve)(KSP,Vec,Vec,void*),void *postctx)
628: {
630: ksp->postsolve = postsolve;
631: ksp->postctx = postctx;
632: return 0;
633: }
635: /*@
636: KSPCreate - Creates the default KSP context.
638: Collective
640: Input Parameter:
641: . comm - MPI communicator
643: Output Parameter:
644: . ksp - location to put the KSP context
646: Notes:
647: The default KSP type is GMRES with a restart of 30, using modified Gram-Schmidt
648: orthogonalization.
650: Level: beginner
652: .seealso: KSPSetUp(), KSPSolve(), KSPDestroy(), KSP
653: @*/
654: PetscErrorCode KSPCreate(MPI_Comm comm,KSP *inksp)
655: {
656: KSP ksp;
657: void *ctx;
660: *inksp = NULL;
661: KSPInitializePackage();
663: PetscHeaderCreate(ksp,KSP_CLASSID,"KSP","Krylov Method","KSP",comm,KSPDestroy,KSPView);
665: ksp->max_it = 10000;
666: ksp->pc_side = ksp->pc_side_set = PC_SIDE_DEFAULT;
667: ksp->rtol = 1.e-5;
668: #if defined(PETSC_USE_REAL_SINGLE)
669: ksp->abstol = 1.e-25;
670: #else
671: ksp->abstol = 1.e-50;
672: #endif
673: ksp->divtol = 1.e4;
675: ksp->chknorm = -1;
676: ksp->normtype = ksp->normtype_set = KSP_NORM_DEFAULT;
677: ksp->rnorm = 0.0;
678: ksp->its = 0;
679: ksp->guess_zero = PETSC_TRUE;
680: ksp->calc_sings = PETSC_FALSE;
681: ksp->res_hist = NULL;
682: ksp->res_hist_alloc = NULL;
683: ksp->res_hist_len = 0;
684: ksp->res_hist_max = 0;
685: ksp->res_hist_reset = PETSC_TRUE;
686: ksp->err_hist = NULL;
687: ksp->err_hist_alloc = NULL;
688: ksp->err_hist_len = 0;
689: ksp->err_hist_max = 0;
690: ksp->err_hist_reset = PETSC_TRUE;
691: ksp->numbermonitors = 0;
692: ksp->numberreasonviews = 0;
693: ksp->setfromoptionscalled = 0;
694: ksp->nmax = PETSC_DECIDE;
696: KSPConvergedDefaultCreate(&ctx);
697: KSPSetConvergenceTest(ksp,KSPConvergedDefault,ctx,KSPConvergedDefaultDestroy);
698: ksp->ops->buildsolution = KSPBuildSolutionDefault;
699: ksp->ops->buildresidual = KSPBuildResidualDefault;
701: ksp->vec_sol = NULL;
702: ksp->vec_rhs = NULL;
703: ksp->pc = NULL;
704: ksp->data = NULL;
705: ksp->nwork = 0;
706: ksp->work = NULL;
707: ksp->reason = KSP_CONVERGED_ITERATING;
708: ksp->setupstage = KSP_SETUP_NEW;
710: KSPNormSupportTableReset_Private(ksp);
712: *inksp = ksp;
713: return 0;
714: }
716: /*@C
717: KSPSetType - Builds KSP for a particular solver.
719: Logically Collective on ksp
721: Input Parameters:
722: + ksp - the Krylov space context
723: - type - a known method
725: Options Database Key:
726: . -ksp_type <method> - Sets the method; use -help for a list
727: of available methods (for instance, cg or gmres)
729: Notes:
730: See "petsc/include/petscksp.h" for available methods (for instance,
731: KSPCG or KSPGMRES).
733: Normally, it is best to use the KSPSetFromOptions() command and
734: then set the KSP type from the options database rather than by using
735: this routine. Using the options database provides the user with
736: maximum flexibility in evaluating the many different Krylov methods.
737: The KSPSetType() routine is provided for those situations where it
738: is necessary to set the iterative solver independently of the command
739: line or options database. This might be the case, for example, when
740: the choice of iterative solver changes during the execution of the
741: program, and the user's application is taking responsibility for
742: choosing the appropriate method. In other words, this routine is
743: not for beginners.
745: Level: intermediate
747: Developer Note: KSPRegister() is used to add Krylov types to KSPList from which they
748: are accessed by KSPSetType().
750: .seealso: PCSetType(), KSPType, KSPRegister(), KSPCreate()
752: @*/
753: PetscErrorCode KSPSetType(KSP ksp, KSPType type)
754: {
755: PetscBool match;
756: PetscErrorCode (*r)(KSP);
761: PetscObjectTypeCompare((PetscObject)ksp,type,&match);
762: if (match) return 0;
764: PetscFunctionListFind(KSPList,type,&r);
766: /* Destroy the previous private KSP context */
767: if (ksp->ops->destroy) {
768: (*ksp->ops->destroy)(ksp);
769: ksp->ops->destroy = NULL;
770: }
771: /* Reinitialize function pointers in KSPOps structure */
772: PetscMemzero(ksp->ops,sizeof(struct _KSPOps));
773: ksp->ops->buildsolution = KSPBuildSolutionDefault;
774: ksp->ops->buildresidual = KSPBuildResidualDefault;
775: KSPNormSupportTableReset_Private(ksp);
776: ksp->setupnewmatrix = PETSC_FALSE; // restore default (setup not called in case of new matrix)
777: /* Call the KSPCreate_XXX routine for this particular Krylov solver */
778: ksp->setupstage = KSP_SETUP_NEW;
779: (*r)(ksp);
780: PetscObjectChangeTypeName((PetscObject)ksp,type);
781: return 0;
782: }
784: /*@C
785: KSPGetType - Gets the KSP type as a string from the KSP object.
787: Not Collective
789: Input Parameter:
790: . ksp - Krylov context
792: Output Parameter:
793: . name - name of KSP method
795: Level: intermediate
797: .seealso: KSPSetType()
798: @*/
799: PetscErrorCode KSPGetType(KSP ksp,KSPType *type)
800: {
803: *type = ((PetscObject)ksp)->type_name;
804: return 0;
805: }
807: /*@C
808: KSPRegister - Adds a method to the Krylov subspace solver package.
810: Not Collective
812: Input Parameters:
813: + name_solver - name of a new user-defined solver
814: - routine_create - routine to create method context
816: Notes:
817: KSPRegister() may be called multiple times to add several user-defined solvers.
819: Sample usage:
820: .vb
821: KSPRegister("my_solver",MySolverCreate);
822: .ve
824: Then, your solver can be chosen with the procedural interface via
825: $ KSPSetType(ksp,"my_solver")
826: or at runtime via the option
827: $ -ksp_type my_solver
829: Level: advanced
831: .seealso: KSPRegisterAll()
832: @*/
833: PetscErrorCode KSPRegister(const char sname[],PetscErrorCode (*function)(KSP))
834: {
835: KSPInitializePackage();
836: PetscFunctionListAdd(&KSPList,sname,function);
837: return 0;
838: }
840: PetscErrorCode KSPMonitorMakeKey_Internal(const char name[], PetscViewerType vtype, PetscViewerFormat format, char key[])
841: {
842: PetscStrncpy(key, name, PETSC_MAX_PATH_LEN);
843: PetscStrlcat(key, ":", PETSC_MAX_PATH_LEN);
844: PetscStrlcat(key, vtype, PETSC_MAX_PATH_LEN);
845: PetscStrlcat(key, ":", PETSC_MAX_PATH_LEN);
846: PetscStrlcat(key, PetscViewerFormats[format], PETSC_MAX_PATH_LEN);
847: return 0;
848: }
850: /*@C
851: KSPMonitorRegister - Adds Krylov subspace solver monitor routine.
853: Not Collective
855: Input Parameters:
856: + name - name of a new monitor routine
857: . vtype - A PetscViewerType for the output
858: . format - A PetscViewerFormat for the output
859: . monitor - Monitor routine
860: . create - Creation routine, or NULL
861: - destroy - Destruction routine, or NULL
863: Notes:
864: KSPMonitorRegister() may be called multiple times to add several user-defined monitors.
866: Sample usage:
867: .vb
868: KSPMonitorRegister("my_monitor",PETSCVIEWERASCII,PETSC_VIEWER_ASCII_INFO_DETAIL,MyMonitor,NULL,NULL);
869: .ve
871: Then, your monitor can be chosen with the procedural interface via
872: $ KSPMonitorSetFromOptions(ksp,"-ksp_monitor_my_monitor","my_monitor",NULL)
873: or at runtime via the option
874: $ -ksp_monitor_my_monitor
876: Level: advanced
878: .seealso: KSPMonitorRegisterAll()
879: @*/
880: PetscErrorCode KSPMonitorRegister(const char name[], PetscViewerType vtype, PetscViewerFormat format,
881: PetscErrorCode (*monitor)(KSP, PetscInt, PetscReal, PetscViewerAndFormat *),
882: PetscErrorCode (*create)(PetscViewer, PetscViewerFormat, void *, PetscViewerAndFormat **),
883: PetscErrorCode (*destroy)(PetscViewerAndFormat **))
884: {
885: char key[PETSC_MAX_PATH_LEN];
887: KSPInitializePackage();
888: KSPMonitorMakeKey_Internal(name, vtype, format, key);
889: PetscFunctionListAdd(&KSPMonitorList, key, monitor);
890: if (create) PetscFunctionListAdd(&KSPMonitorCreateList, key, create);
891: if (destroy) PetscFunctionListAdd(&KSPMonitorDestroyList, key, destroy);
892: return 0;
893: }