Actual source code: snes.c
petsc-3.10.2 2018-10-09
1: #include <petsc/private/snesimpl.h>
2: #include <petscdmshell.h>
3: #include <petscdraw.h>
4: #include <petscds.h>
5: #include <petscdmadaptor.h>
6: #include <petscconvest.h>
8: PetscBool SNESRegisterAllCalled = PETSC_FALSE;
9: PetscFunctionList SNESList = NULL;
11: /* Logging support */
12: PetscClassId SNES_CLASSID, DMSNES_CLASSID;
13: PetscLogEvent SNES_Solve, SNES_FunctionEval, SNES_JacobianEval, SNES_NGSEval, SNES_NGSFuncEval, SNES_NPCSolve, SNES_ObjectiveEval;
15: /*@
16: SNESSetErrorIfNotConverged - Causes SNESSolve() to generate an error if the solver has not converged.
18: Logically Collective on SNES
20: Input Parameters:
21: + snes - iterative context obtained from SNESCreate()
22: - flg - PETSC_TRUE indicates you want the error generated
24: Options database keys:
25: . -snes_error_if_not_converged : this takes an optional truth value (0/1/no/yes/true/false)
27: Level: intermediate
29: Notes:
30: Normally PETSc continues if a linear solver fails to converge, you can call SNESGetConvergedReason() after a SNESSolve()
31: to determine if it has converged.
33: .keywords: SNES, set, initial guess, nonzero
35: .seealso: SNESGetErrorIfNotConverged(), KSPGetErrorIfNotConverged(), KSPSetErrorIFNotConverged()
36: @*/
37: PetscErrorCode SNESSetErrorIfNotConverged(SNES snes,PetscBool flg)
38: {
42: snes->errorifnotconverged = flg;
43: return(0);
44: }
46: /*@
47: SNESGetErrorIfNotConverged - Will SNESSolve() generate an error if the solver does not converge?
49: Not Collective
51: Input Parameter:
52: . snes - iterative context obtained from SNESCreate()
54: Output Parameter:
55: . flag - PETSC_TRUE if it will generate an error, else PETSC_FALSE
57: Level: intermediate
59: .keywords: SNES, set, initial guess, nonzero
61: .seealso: SNESSetErrorIfNotConverged(), KSPGetErrorIfNotConverged(), KSPSetErrorIFNotConverged()
62: @*/
63: PetscErrorCode SNESGetErrorIfNotConverged(SNES snes,PetscBool *flag)
64: {
68: *flag = snes->errorifnotconverged;
69: return(0);
70: }
72: /*@
73: SNESSetAlwaysComputesFinalResidual - does the SNES always compute the residual at the final solution?
75: Logically Collective on SNES
77: Input Parameters:
78: + snes - the shell SNES
79: - flg - is the residual computed?
81: Level: advanced
83: .seealso: SNESGetAlwaysComputesFinalResidual()
84: @*/
85: PetscErrorCode SNESSetAlwaysComputesFinalResidual(SNES snes, PetscBool flg)
86: {
89: snes->alwayscomputesfinalresidual = flg;
90: return(0);
91: }
93: /*@
94: SNESGetAlwaysComputesFinalResidual - does the SNES always compute the residual at the final solution?
96: Logically Collective on SNES
98: Input Parameter:
99: . snes - the shell SNES
101: Output Parameter:
102: . flg - is the residual computed?
104: Level: advanced
106: .seealso: SNESSetAlwaysComputesFinalResidual()
107: @*/
108: PetscErrorCode SNESGetAlwaysComputesFinalResidual(SNES snes, PetscBool *flg)
109: {
112: *flg = snes->alwayscomputesfinalresidual;
113: return(0);
114: }
116: /*@
117: SNESSetFunctionDomainError - tells SNES that the input vector to your SNESFunction is not
118: in the functions domain. For example, negative pressure.
120: Logically Collective on SNES
122: Input Parameters:
123: . snes - the SNES context
125: Level: advanced
127: .keywords: SNES, view
129: .seealso: SNESCreate(), SNESSetFunction(), SNESFunction
130: @*/
131: PetscErrorCode SNESSetFunctionDomainError(SNES snes)
132: {
135: if (snes->errorifnotconverged) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"User code indicates input vector is not in the function domain");
136: snes->domainerror = PETSC_TRUE;
137: return(0);
138: }
140: /*@
141: SNESGetFunctionDomainError - Gets the status of the domain error after a call to SNESComputeFunction;
143: Logically Collective on SNES
145: Input Parameters:
146: . snes - the SNES context
148: Output Parameters:
149: . domainerror - Set to PETSC_TRUE if there's a domain error; PETSC_FALSE otherwise.
151: Level: advanced
153: .keywords: SNES, view
155: .seealso: SNESSetFunctionDomainError(), SNESComputeFunction()
156: @*/
157: PetscErrorCode SNESGetFunctionDomainError(SNES snes, PetscBool *domainerror)
158: {
162: *domainerror = snes->domainerror;
163: return(0);
164: }
166: /*@C
167: SNESLoad - Loads a SNES that has been stored in binary with SNESView().
169: Collective on PetscViewer
171: Input Parameters:
172: + newdm - the newly loaded SNES, this needs to have been created with SNESCreate() or
173: some related function before a call to SNESLoad().
174: - viewer - binary file viewer, obtained from PetscViewerBinaryOpen()
176: Level: intermediate
178: Notes:
179: The type is determined by the data in the file, any type set into the SNES before this call is ignored.
181: Notes for advanced users:
182: Most users should not need to know the details of the binary storage
183: format, since SNESLoad() and TSView() completely hide these details.
184: But for anyone who's interested, the standard binary matrix storage
185: format is
186: .vb
187: has not yet been determined
188: .ve
190: .seealso: PetscViewerBinaryOpen(), SNESView(), MatLoad(), VecLoad()
191: @*/
192: PetscErrorCode SNESLoad(SNES snes, PetscViewer viewer)
193: {
195: PetscBool isbinary;
196: PetscInt classid;
197: char type[256];
198: KSP ksp;
199: DM dm;
200: DMSNES dmsnes;
205: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);
206: if (!isbinary) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Invalid viewer; open viewer with PetscViewerBinaryOpen()");
208: PetscViewerBinaryRead(viewer,&classid,1,NULL,PETSC_INT);
209: if (classid != SNES_FILE_CLASSID) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONG,"Not SNES next in file");
210: PetscViewerBinaryRead(viewer,type,256,NULL,PETSC_CHAR);
211: SNESSetType(snes, type);
212: if (snes->ops->load) {
213: (*snes->ops->load)(snes,viewer);
214: }
215: SNESGetDM(snes,&dm);
216: DMGetDMSNES(dm,&dmsnes);
217: DMSNESLoad(dmsnes,viewer);
218: SNESGetKSP(snes,&ksp);
219: KSPLoad(ksp,viewer);
220: return(0);
221: }
223: #include <petscdraw.h>
224: #if defined(PETSC_HAVE_SAWS)
225: #include <petscviewersaws.h>
226: #endif
228: /*@C
229: SNESView - Prints the SNES data structure.
231: Collective on SNES
233: Input Parameters:
234: + SNES - the SNES context
235: - viewer - visualization context
237: Options Database Key:
238: . -snes_view - Calls SNESView() at end of SNESSolve()
240: Notes:
241: The available visualization contexts include
242: + PETSC_VIEWER_STDOUT_SELF - standard output (default)
243: - PETSC_VIEWER_STDOUT_WORLD - synchronized standard
244: output where only the first processor opens
245: the file. All other processors send their
246: data to the first processor to print.
248: The user can open an alternative visualization context with
249: PetscViewerASCIIOpen() - output to a specified file.
251: Level: beginner
253: .keywords: SNES, view
255: .seealso: PetscViewerASCIIOpen()
256: @*/
257: PetscErrorCode SNESView(SNES snes,PetscViewer viewer)
258: {
259: SNESKSPEW *kctx;
261: KSP ksp;
262: SNESLineSearch linesearch;
263: PetscBool iascii,isstring,isbinary,isdraw;
264: DMSNES dmsnes;
265: #if defined(PETSC_HAVE_SAWS)
266: PetscBool issaws;
267: #endif
271: if (!viewer) {
272: PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)snes),&viewer);
273: }
277: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);
278: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSTRING,&isstring);
279: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);
280: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);
281: #if defined(PETSC_HAVE_SAWS)
282: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSAWS,&issaws);
283: #endif
284: if (iascii) {
285: SNESNormSchedule normschedule;
286: DM dm;
287: PetscErrorCode (*cJ)(SNES,Vec,Mat,Mat,void*);
288: void *ctx;
290: PetscObjectPrintClassNamePrefixType((PetscObject)snes,viewer);
291: if (!snes->setupcalled) {
292: PetscViewerASCIIPrintf(viewer," SNES has not been set up so information may be incomplete\n");
293: }
294: if (snes->ops->view) {
295: PetscViewerASCIIPushTab(viewer);
296: (*snes->ops->view)(snes,viewer);
297: PetscViewerASCIIPopTab(viewer);
298: }
299: PetscViewerASCIIPrintf(viewer," maximum iterations=%D, maximum function evaluations=%D\n",snes->max_its,snes->max_funcs);
300: PetscViewerASCIIPrintf(viewer," tolerances: relative=%g, absolute=%g, solution=%g\n",(double)snes->rtol,(double)snes->abstol,(double)snes->stol);
301: if (snes->usesksp) {
302: PetscViewerASCIIPrintf(viewer," total number of linear solver iterations=%D\n",snes->linear_its);
303: }
304: PetscViewerASCIIPrintf(viewer," total number of function evaluations=%D\n",snes->nfuncs);
305: SNESGetNormSchedule(snes, &normschedule);
306: if (normschedule > 0) {PetscViewerASCIIPrintf(viewer," norm schedule %s\n",SNESNormSchedules[normschedule]);}
307: if (snes->gridsequence) {
308: PetscViewerASCIIPrintf(viewer," total number of grid sequence refinements=%D\n",snes->gridsequence);
309: }
310: if (snes->ksp_ewconv) {
311: kctx = (SNESKSPEW*)snes->kspconvctx;
312: if (kctx) {
313: PetscViewerASCIIPrintf(viewer," Eisenstat-Walker computation of KSP relative tolerance (version %D)\n",kctx->version);
314: PetscViewerASCIIPrintf(viewer," rtol_0=%g, rtol_max=%g, threshold=%g\n",(double)kctx->rtol_0,(double)kctx->rtol_max,(double)kctx->threshold);
315: PetscViewerASCIIPrintf(viewer," gamma=%g, alpha=%g, alpha2=%g\n",(double)kctx->gamma,(double)kctx->alpha,(double)kctx->alpha2);
316: }
317: }
318: if (snes->lagpreconditioner == -1) {
319: PetscViewerASCIIPrintf(viewer," Preconditioned is never rebuilt\n");
320: } else if (snes->lagpreconditioner > 1) {
321: PetscViewerASCIIPrintf(viewer," Preconditioned is rebuilt every %D new Jacobians\n",snes->lagpreconditioner);
322: }
323: if (snes->lagjacobian == -1) {
324: PetscViewerASCIIPrintf(viewer," Jacobian is never rebuilt\n");
325: } else if (snes->lagjacobian > 1) {
326: PetscViewerASCIIPrintf(viewer," Jacobian is rebuilt every %D SNES iterations\n",snes->lagjacobian);
327: }
328: SNESGetDM(snes,&dm);
329: DMSNESGetJacobian(dm,&cJ,&ctx);
330: if (cJ == SNESComputeJacobianDefault) {
331: PetscViewerASCIIPrintf(viewer," Jacobian is built using finite differences one column at a time\n");
332: } else if (cJ == SNESComputeJacobianDefaultColor) {
333: PetscViewerASCIIPrintf(viewer," Jacobian is built using finite differences with coloring\n");
334: }
335: } else if (isstring) {
336: const char *type;
337: SNESGetType(snes,&type);
338: PetscViewerStringSPrintf(viewer," %-3.3s",type);
339: } else if (isbinary) {
340: PetscInt classid = SNES_FILE_CLASSID;
341: MPI_Comm comm;
342: PetscMPIInt rank;
343: char type[256];
345: PetscObjectGetComm((PetscObject)snes,&comm);
346: MPI_Comm_rank(comm,&rank);
347: if (!rank) {
348: PetscViewerBinaryWrite(viewer,&classid,1,PETSC_INT,PETSC_FALSE);
349: PetscStrncpy(type,((PetscObject)snes)->type_name,sizeof(type));
350: PetscViewerBinaryWrite(viewer,type,sizeof(type),PETSC_CHAR,PETSC_FALSE);
351: }
352: if (snes->ops->view) {
353: (*snes->ops->view)(snes,viewer);
354: }
355: } else if (isdraw) {
356: PetscDraw draw;
357: char str[36];
358: PetscReal x,y,bottom,h;
360: PetscViewerDrawGetDraw(viewer,0,&draw);
361: PetscDrawGetCurrentPoint(draw,&x,&y);
362: PetscStrncpy(str,"SNES: ",sizeof(str));
363: PetscStrlcat(str,((PetscObject)snes)->type_name,sizeof(str));
364: PetscDrawStringBoxed(draw,x,y,PETSC_DRAW_BLUE,PETSC_DRAW_BLACK,str,NULL,&h);
365: bottom = y - h;
366: PetscDrawPushCurrentPoint(draw,x,bottom);
367: if (snes->ops->view) {
368: (*snes->ops->view)(snes,viewer);
369: }
370: #if defined(PETSC_HAVE_SAWS)
371: } else if (issaws) {
372: PetscMPIInt rank;
373: const char *name;
375: PetscObjectGetName((PetscObject)snes,&name);
376: MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
377: if (!((PetscObject)snes)->amsmem && !rank) {
378: char dir[1024];
380: PetscObjectViewSAWs((PetscObject)snes,viewer);
381: PetscSNPrintf(dir,1024,"/PETSc/Objects/%s/its",name);
382: PetscStackCallSAWs(SAWs_Register,(dir,&snes->iter,1,SAWs_READ,SAWs_INT));
383: if (!snes->conv_hist) {
384: SNESSetConvergenceHistory(snes,NULL,NULL,PETSC_DECIDE,PETSC_TRUE);
385: }
386: PetscSNPrintf(dir,1024,"/PETSc/Objects/%s/conv_hist",name);
387: PetscStackCallSAWs(SAWs_Register,(dir,snes->conv_hist,10,SAWs_READ,SAWs_DOUBLE));
388: }
389: #endif
390: }
391: if (snes->linesearch) {
392: SNESGetLineSearch(snes, &linesearch);
393: PetscViewerASCIIPushTab(viewer);
394: SNESLineSearchView(linesearch, viewer);
395: PetscViewerASCIIPopTab(viewer);
396: }
397: if (snes->npc && snes->usesnpc) {
398: PetscViewerASCIIPushTab(viewer);
399: SNESView(snes->npc, viewer);
400: PetscViewerASCIIPopTab(viewer);
401: }
402: PetscViewerASCIIPushTab(viewer);
403: DMGetDMSNES(snes->dm,&dmsnes);
404: DMSNESView(dmsnes, viewer);
405: PetscViewerASCIIPopTab(viewer);
406: if (snes->usesksp) {
407: SNESGetKSP(snes,&ksp);
408: PetscViewerASCIIPushTab(viewer);
409: KSPView(ksp,viewer);
410: PetscViewerASCIIPopTab(viewer);
411: }
412: if (isdraw) {
413: PetscDraw draw;
414: PetscViewerDrawGetDraw(viewer,0,&draw);
415: PetscDrawPopCurrentPoint(draw);
416: }
417: return(0);
418: }
420: /*
421: We retain a list of functions that also take SNES command
422: line options. These are called at the end SNESSetFromOptions()
423: */
424: #define MAXSETFROMOPTIONS 5
425: static PetscInt numberofsetfromoptions;
426: static PetscErrorCode (*othersetfromoptions[MAXSETFROMOPTIONS])(SNES);
428: /*@C
429: SNESAddOptionsChecker - Adds an additional function to check for SNES options.
431: Not Collective
433: Input Parameter:
434: . snescheck - function that checks for options
436: Level: developer
438: .seealso: SNESSetFromOptions()
439: @*/
440: PetscErrorCode SNESAddOptionsChecker(PetscErrorCode (*snescheck)(SNES))
441: {
443: if (numberofsetfromoptions >= MAXSETFROMOPTIONS) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE, "Too many options checkers, only %D allowed", MAXSETFROMOPTIONS);
444: othersetfromoptions[numberofsetfromoptions++] = snescheck;
445: return(0);
446: }
448: PETSC_INTERN PetscErrorCode SNESDefaultMatrixFreeCreate2(SNES,Vec,Mat*);
450: static PetscErrorCode SNESSetUpMatrixFree_Private(SNES snes, PetscBool hasOperator, PetscInt version)
451: {
452: Mat J;
453: KSP ksp;
454: PC pc;
455: PetscBool match;
457: MatNullSpace nullsp;
462: if (!snes->vec_func && (snes->jacobian || snes->jacobian_pre)) {
463: Mat A = snes->jacobian, B = snes->jacobian_pre;
464: MatCreateVecs(A ? A : B, NULL,&snes->vec_func);
465: }
467: if (version == 1) {
468: MatCreateSNESMF(snes,&J);
469: MatMFFDSetOptionsPrefix(J,((PetscObject)snes)->prefix);
470: MatSetFromOptions(J);
471: } else if (version == 2) {
472: if (!snes->vec_func) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"SNESSetFunction() must be called first");
473: #if !defined(PETSC_USE_COMPLEX) && !defined(PETSC_USE_REAL_SINGLE) && !defined(PETSC_USE_REAL___FLOAT128) && !defined(PETSC_USE_REAL___FP16)
474: SNESDefaultMatrixFreeCreate2(snes,snes->vec_func,&J);
475: #else
476: SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP, "matrix-free operator rutines (version 2)");
477: #endif
478: } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE, "matrix-free operator rutines, only version 1 and 2");
480: /* attach any user provided null space that was on Amat to the newly created matrix free matrix */
481: if (snes->jacobian) {
482: MatGetNullSpace(snes->jacobian,&nullsp);
483: if (nullsp) {
484: MatSetNullSpace(J,nullsp);
485: }
486: }
488: PetscInfo1(snes,"Setting default matrix-free operator routines (version %D)\n", version);
489: if (hasOperator) {
491: /* This version replaces the user provided Jacobian matrix with a
492: matrix-free version but still employs the user-provided preconditioner matrix. */
493: SNESSetJacobian(snes,J,0,0,0);
494: } else {
495: /* This version replaces both the user-provided Jacobian and the user-
496: provided preconditioner Jacobian with the default matrix free version. */
497: if ((snes->npcside== PC_LEFT) && snes->npc) {
498: if (!snes->jacobian){SNESSetJacobian(snes,J,0,0,0);}
499: } else {
500: SNESSetJacobian(snes,J,J,MatMFFDComputeJacobian,0);
501: }
502: /* Force no preconditioner */
503: SNESGetKSP(snes,&ksp);
504: KSPGetPC(ksp,&pc);
505: PetscObjectTypeCompare((PetscObject)pc,PCSHELL,&match);
506: if (!match) {
507: PetscInfo(snes,"Setting default matrix-free preconditioner routines\nThat is no preconditioner is being used\n");
508: PCSetType(pc,PCNONE);
509: }
510: }
511: MatDestroy(&J);
512: return(0);
513: }
515: static PetscErrorCode DMRestrictHook_SNESVecSol(DM dmfine,Mat Restrict,Vec Rscale,Mat Inject,DM dmcoarse,void *ctx)
516: {
517: SNES snes = (SNES)ctx;
519: Vec Xfine,Xfine_named = NULL,Xcoarse;
522: if (PetscLogPrintInfo) {
523: PetscInt finelevel,coarselevel,fineclevel,coarseclevel;
524: DMGetRefineLevel(dmfine,&finelevel);
525: DMGetCoarsenLevel(dmfine,&fineclevel);
526: DMGetRefineLevel(dmcoarse,&coarselevel);
527: DMGetCoarsenLevel(dmcoarse,&coarseclevel);
528: PetscInfo4(dmfine,"Restricting SNES solution vector from level %D-%D to level %D-%D\n",finelevel,fineclevel,coarselevel,coarseclevel);
529: }
530: if (dmfine == snes->dm) Xfine = snes->vec_sol;
531: else {
532: DMGetNamedGlobalVector(dmfine,"SNESVecSol",&Xfine_named);
533: Xfine = Xfine_named;
534: }
535: DMGetNamedGlobalVector(dmcoarse,"SNESVecSol",&Xcoarse);
536: if (Inject) {
537: MatRestrict(Inject,Xfine,Xcoarse);
538: } else {
539: MatRestrict(Restrict,Xfine,Xcoarse);
540: VecPointwiseMult(Xcoarse,Xcoarse,Rscale);
541: }
542: DMRestoreNamedGlobalVector(dmcoarse,"SNESVecSol",&Xcoarse);
543: if (Xfine_named) {DMRestoreNamedGlobalVector(dmfine,"SNESVecSol",&Xfine_named);}
544: return(0);
545: }
547: static PetscErrorCode DMCoarsenHook_SNESVecSol(DM dm,DM dmc,void *ctx)
548: {
552: DMCoarsenHookAdd(dmc,DMCoarsenHook_SNESVecSol,DMRestrictHook_SNESVecSol,ctx);
553: return(0);
554: }
556: /* This may be called to rediscretize the operator on levels of linear multigrid. The DM shuffle is so the user can
557: * safely call SNESGetDM() in their residual evaluation routine. */
558: static PetscErrorCode KSPComputeOperators_SNES(KSP ksp,Mat A,Mat B,void *ctx)
559: {
560: SNES snes = (SNES)ctx;
562: Mat Asave = A,Bsave = B;
563: Vec X,Xnamed = NULL;
564: DM dmsave;
565: void *ctxsave;
566: PetscErrorCode (*jac)(SNES,Vec,Mat,Mat,void*) = NULL;
569: dmsave = snes->dm;
570: KSPGetDM(ksp,&snes->dm);
571: if (dmsave == snes->dm) X = snes->vec_sol; /* We are on the finest level */
572: else { /* We are on a coarser level, this vec was initialized using a DM restrict hook */
573: DMGetNamedGlobalVector(snes->dm,"SNESVecSol",&Xnamed);
574: X = Xnamed;
575: SNESGetJacobian(snes,NULL,NULL,&jac,&ctxsave);
576: /* If the DM's don't match up, the MatFDColoring context needed for the jacobian won't match up either -- fixit. */
577: if (jac == SNESComputeJacobianDefaultColor) {
578: SNESSetJacobian(snes,NULL,NULL,SNESComputeJacobianDefaultColor,0);
579: }
580: }
581: /* put the previous context back */
583: SNESComputeJacobian(snes,X,A,B);
584: if (snes->dm != dmsave && jac == SNESComputeJacobianDefaultColor) {
585: SNESSetJacobian(snes,NULL,NULL,jac,ctxsave);
586: }
588: if (A != Asave || B != Bsave) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_SUP,"No support for changing matrices at this time");
589: if (Xnamed) {
590: DMRestoreNamedGlobalVector(snes->dm,"SNESVecSol",&Xnamed);
591: }
592: snes->dm = dmsave;
593: return(0);
594: }
596: /*@
597: SNESSetUpMatrices - ensures that matrices are available for SNES, to be called by SNESSetUp_XXX()
599: Collective
601: Input Arguments:
602: . snes - snes to configure
604: Level: developer
606: .seealso: SNESSetUp()
607: @*/
608: PetscErrorCode SNESSetUpMatrices(SNES snes)
609: {
611: DM dm;
612: DMSNES sdm;
615: SNESGetDM(snes,&dm);
616: DMGetDMSNES(dm,&sdm);
617: if (!sdm->ops->computejacobian) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_PLIB,"DMSNES not properly configured");
618: else if (!snes->jacobian && snes->mf) {
619: Mat J;
620: void *functx;
621: MatCreateSNESMF(snes,&J);
622: MatMFFDSetOptionsPrefix(J,((PetscObject)snes)->prefix);
623: MatSetFromOptions(J);
624: SNESGetFunction(snes,NULL,NULL,&functx);
625: SNESSetJacobian(snes,J,J,0,0);
626: MatDestroy(&J);
627: } else if (snes->mf_operator && !snes->jacobian_pre && !snes->jacobian) {
628: Mat J,B;
629: MatCreateSNESMF(snes,&J);
630: MatMFFDSetOptionsPrefix(J,((PetscObject)snes)->prefix);
631: MatSetFromOptions(J);
632: DMCreateMatrix(snes->dm,&B);
633: /* sdm->computejacobian was already set to reach here */
634: SNESSetJacobian(snes,J,B,NULL,NULL);
635: MatDestroy(&J);
636: MatDestroy(&B);
637: } else if (!snes->jacobian_pre) {
638: PetscErrorCode (*nspconstr)(DM, PetscInt, MatNullSpace *);
639: PetscDS prob;
640: Mat J, B;
641: MatNullSpace nullspace = NULL;
642: PetscBool hasPrec = PETSC_FALSE;
643: PetscInt Nf;
645: J = snes->jacobian;
646: DMGetDS(dm, &prob);
647: if (prob) {PetscDSHasJacobianPreconditioner(prob, &hasPrec);}
648: if (J) {PetscObjectReference((PetscObject) J);}
649: else if (hasPrec) {DMCreateMatrix(snes->dm, &J);}
650: DMCreateMatrix(snes->dm, &B);
651: PetscDSGetNumFields(prob, &Nf);
652: DMGetNullSpaceConstructor(snes->dm, Nf, &nspconstr);
653: if (nspconstr) (*nspconstr)(snes->dm, -1, &nullspace);
654: MatSetNullSpace(B, nullspace);
655: MatNullSpaceDestroy(&nullspace);
656: SNESSetJacobian(snes, J ? J : B, B, NULL, NULL);
657: MatDestroy(&J);
658: MatDestroy(&B);
659: }
660: {
661: KSP ksp;
662: SNESGetKSP(snes,&ksp);
663: KSPSetComputeOperators(ksp,KSPComputeOperators_SNES,snes);
664: DMCoarsenHookAdd(snes->dm,DMCoarsenHook_SNESVecSol,DMRestrictHook_SNESVecSol,snes);
665: }
666: return(0);
667: }
669: /*@C
670: SNESMonitorSetFromOptions - Sets a monitor function and viewer appropriate for the type indicated by the user
672: Collective on SNES
674: Input Parameters:
675: + snes - SNES object you wish to monitor
676: . name - the monitor type one is seeking
677: . help - message indicating what monitoring is done
678: . manual - manual page for the monitor
679: . monitor - the monitor function
680: - monitorsetup - a function that is called once ONLY if the user selected this monitor that may set additional features of the SNES or PetscViewer objects
682: Level: developer
684: .seealso: PetscOptionsGetViewer(), PetscOptionsGetReal(), PetscOptionsHasName(), PetscOptionsGetString(),
685: PetscOptionsGetIntArray(), PetscOptionsGetRealArray(), PetscOptionsBool()
686: PetscOptionsInt(), PetscOptionsString(), PetscOptionsReal(), PetscOptionsBool(),
687: PetscOptionsName(), PetscOptionsBegin(), PetscOptionsEnd(), PetscOptionsHead(),
688: PetscOptionsStringArray(),PetscOptionsRealArray(), PetscOptionsScalar(),
689: PetscOptionsBoolGroupBegin(), PetscOptionsBoolGroup(), PetscOptionsBoolGroupEnd(),
690: PetscOptionsFList(), PetscOptionsEList()
691: @*/
692: PetscErrorCode SNESMonitorSetFromOptions(SNES snes,const char name[],const char help[], const char manual[],PetscErrorCode (*monitor)(SNES,PetscInt,PetscReal,PetscViewerAndFormat*),PetscErrorCode (*monitorsetup)(SNES,PetscViewerAndFormat*))
693: {
694: PetscErrorCode ierr;
695: PetscViewer viewer;
696: PetscViewerFormat format;
697: PetscBool flg;
700: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,name,&viewer,&format,&flg);
701: if (flg) {
702: PetscViewerAndFormat *vf;
703: PetscViewerAndFormatCreate(viewer,format,&vf);
704: PetscObjectDereference((PetscObject)viewer);
705: if (monitorsetup) {
706: (*monitorsetup)(snes,vf);
707: }
708: SNESMonitorSet(snes,(PetscErrorCode (*)(SNES,PetscInt,PetscReal,void*))monitor,vf,(PetscErrorCode (*)(void**))PetscViewerAndFormatDestroy);
709: }
710: return(0);
711: }
713: /*@
714: SNESSetFromOptions - Sets various SNES and KSP parameters from user options.
716: Collective on SNES
718: Input Parameter:
719: . snes - the SNES context
721: Options Database Keys:
722: + -snes_type <type> - newtonls, newtontr, ngmres, ncg, nrichardson, qn, vi, fas, SNESType for complete list
723: . -snes_stol - convergence tolerance in terms of the norm
724: of the change in the solution between steps
725: . -snes_atol <abstol> - absolute tolerance of residual norm
726: . -snes_rtol <rtol> - relative decrease in tolerance norm from initial
727: . -snes_divergence_tolerance <divtol> - if the residual goes above divtol*rnorm0, exit with divergence
728: . -snes_force_iteration <force> - force SNESSolve() to take at least one iteration
729: . -snes_max_it <max_it> - maximum number of iterations
730: . -snes_max_funcs <max_funcs> - maximum number of function evaluations
731: . -snes_max_fail <max_fail> - maximum number of line search failures allowed before stopping, default is none
732: . -snes_max_linear_solve_fail - number of linear solver failures before SNESSolve() stops
733: . -snes_lag_preconditioner <lag> - how often preconditioner is rebuilt (use -1 to never rebuild)
734: . -snes_lag_jacobian <lag> - how often Jacobian is rebuilt (use -1 to never rebuild)
735: . -snes_trtol <trtol> - trust region tolerance
736: . -snes_no_convergence_test - skip convergence test in nonlinear
737: solver; hence iterations will continue until max_it
738: or some other criterion is reached. Saves expense
739: of convergence test
740: . -snes_monitor [ascii][:filename][:viewer format] - prints residual norm at each iteration. if no filename given prints to stdout
741: . -snes_monitor_solution [ascii binary draw][:filename][:viewer format] - plots solution at each iteration
742: . -snes_monitor_residual [ascii binary draw][:filename][:viewer format] - plots residual (not its norm) at each iteration
743: . -snes_monitor_solution_update [ascii binary draw][:filename][:viewer format] - plots update to solution at each iteration
744: . -snes_monitor_lg_residualnorm - plots residual norm at each iteration
745: . -snes_monitor_lg_range - plots residual norm at each iteration
746: . -snes_fd - use finite differences to compute Jacobian; very slow, only for testing
747: . -snes_fd_color - use finite differences with coloring to compute Jacobian
748: . -snes_mf_ksp_monitor - if using matrix-free multiply then print h at each KSP iteration
749: - -snes_converged_reason - print the reason for convergence/divergence after each solve
751: Options Database for Eisenstat-Walker method:
752: + -snes_ksp_ew - use Eisenstat-Walker method for determining linear system convergence
753: . -snes_ksp_ew_version ver - version of Eisenstat-Walker method
754: . -snes_ksp_ew_rtol0 <rtol0> - Sets rtol0
755: . -snes_ksp_ew_rtolmax <rtolmax> - Sets rtolmax
756: . -snes_ksp_ew_gamma <gamma> - Sets gamma
757: . -snes_ksp_ew_alpha <alpha> - Sets alpha
758: . -snes_ksp_ew_alpha2 <alpha2> - Sets alpha2
759: - -snes_ksp_ew_threshold <threshold> - Sets threshold
761: Notes:
762: To see all options, run your program with the -help option or consult
763: Users-Manual: ch_snes
765: Level: beginner
767: .keywords: SNES, nonlinear, set, options, database
769: .seealso: SNESSetOptionsPrefix(), SNESResetFromOptions()
770: @*/
771: PetscErrorCode SNESSetFromOptions(SNES snes)
772: {
773: PetscBool flg,pcset,persist,set;
774: PetscInt i,indx,lag,grids;
775: const char *deft = SNESNEWTONLS;
776: const char *convtests[] = {"default","skip"};
777: SNESKSPEW *kctx = NULL;
778: char type[256], monfilename[PETSC_MAX_PATH_LEN];
780: PCSide pcside;
781: const char *optionsprefix;
785: SNESRegisterAll();
786: PetscObjectOptionsBegin((PetscObject)snes);
787: if (((PetscObject)snes)->type_name) deft = ((PetscObject)snes)->type_name;
788: PetscOptionsFList("-snes_type","Nonlinear solver method","SNESSetType",SNESList,deft,type,256,&flg);
789: if (flg) {
790: SNESSetType(snes,type);
791: } else if (!((PetscObject)snes)->type_name) {
792: SNESSetType(snes,deft);
793: }
794: PetscOptionsReal("-snes_stol","Stop if step length less than","SNESSetTolerances",snes->stol,&snes->stol,NULL);
795: PetscOptionsReal("-snes_atol","Stop if function norm less than","SNESSetTolerances",snes->abstol,&snes->abstol,NULL);
797: PetscOptionsReal("-snes_rtol","Stop if decrease in function norm less than","SNESSetTolerances",snes->rtol,&snes->rtol,NULL);
798: PetscOptionsReal("-snes_divergence_tolerance","Stop if residual norm increases by this factor","SNESSetDivergenceTolerance",snes->divtol,&snes->divtol,NULL);
799: PetscOptionsInt("-snes_max_it","Maximum iterations","SNESSetTolerances",snes->max_its,&snes->max_its,NULL);
800: PetscOptionsInt("-snes_max_funcs","Maximum function evaluations","SNESSetTolerances",snes->max_funcs,&snes->max_funcs,NULL);
801: PetscOptionsInt("-snes_max_fail","Maximum nonlinear step failures","SNESSetMaxNonlinearStepFailures",snes->maxFailures,&snes->maxFailures,NULL);
802: PetscOptionsInt("-snes_max_linear_solve_fail","Maximum failures in linear solves allowed","SNESSetMaxLinearSolveFailures",snes->maxLinearSolveFailures,&snes->maxLinearSolveFailures,NULL);
803: PetscOptionsBool("-snes_error_if_not_converged","Generate error if solver does not converge","SNESSetErrorIfNotConverged",snes->errorifnotconverged,&snes->errorifnotconverged,NULL);
804: PetscOptionsBool("-snes_force_iteration","Force SNESSolve() to take at least one iteration","SNESSetForceIteration",snes->forceiteration,&snes->forceiteration,NULL);
806: PetscOptionsInt("-snes_lag_preconditioner","How often to rebuild preconditioner","SNESSetLagPreconditioner",snes->lagpreconditioner,&lag,&flg);
807: if (flg) {
808: SNESSetLagPreconditioner(snes,lag);
809: }
810: PetscOptionsBool("-snes_lag_preconditioner_persists","Preconditioner lagging through multiple solves","SNESSetLagPreconditionerPersists",snes->lagjac_persist,&persist,&flg);
811: if (flg) {
812: SNESSetLagPreconditionerPersists(snes,persist);
813: }
814: PetscOptionsInt("-snes_lag_jacobian","How often to rebuild Jacobian","SNESSetLagJacobian",snes->lagjacobian,&lag,&flg);
815: if (flg) {
816: SNESSetLagJacobian(snes,lag);
817: }
818: PetscOptionsBool("-snes_lag_jacobian_persists","Jacobian lagging through multiple solves","SNESSetLagJacobianPersists",snes->lagjac_persist,&persist,&flg);
819: if (flg) {
820: SNESSetLagJacobianPersists(snes,persist);
821: }
823: PetscOptionsInt("-snes_grid_sequence","Use grid sequencing to generate initial guess","SNESSetGridSequence",snes->gridsequence,&grids,&flg);
824: if (flg) {
825: SNESSetGridSequence(snes,grids);
826: }
828: PetscOptionsEList("-snes_convergence_test","Convergence test","SNESSetConvergenceTest",convtests,2,"default",&indx,&flg);
829: if (flg) {
830: switch (indx) {
831: case 0: SNESSetConvergenceTest(snes,SNESConvergedDefault,NULL,NULL); break;
832: case 1: SNESSetConvergenceTest(snes,SNESConvergedSkip,NULL,NULL); break;
833: }
834: }
836: PetscOptionsEList("-snes_norm_schedule","SNES Norm schedule","SNESSetNormSchedule",SNESNormSchedules,5,"function",&indx,&flg);
837: if (flg) { SNESSetNormSchedule(snes,(SNESNormSchedule)indx); }
839: PetscOptionsEList("-snes_function_type","SNES Norm schedule","SNESSetFunctionType",SNESFunctionTypes,2,"unpreconditioned",&indx,&flg);
840: if (flg) { SNESSetFunctionType(snes,(SNESFunctionType)indx); }
842: kctx = (SNESKSPEW*)snes->kspconvctx;
844: PetscOptionsBool("-snes_ksp_ew","Use Eisentat-Walker linear system convergence test","SNESKSPSetUseEW",snes->ksp_ewconv,&snes->ksp_ewconv,NULL);
846: PetscOptionsInt("-snes_ksp_ew_version","Version 1, 2 or 3","SNESKSPSetParametersEW",kctx->version,&kctx->version,NULL);
847: PetscOptionsReal("-snes_ksp_ew_rtol0","0 <= rtol0 < 1","SNESKSPSetParametersEW",kctx->rtol_0,&kctx->rtol_0,NULL);
848: PetscOptionsReal("-snes_ksp_ew_rtolmax","0 <= rtolmax < 1","SNESKSPSetParametersEW",kctx->rtol_max,&kctx->rtol_max,NULL);
849: PetscOptionsReal("-snes_ksp_ew_gamma","0 <= gamma <= 1","SNESKSPSetParametersEW",kctx->gamma,&kctx->gamma,NULL);
850: PetscOptionsReal("-snes_ksp_ew_alpha","1 < alpha <= 2","SNESKSPSetParametersEW",kctx->alpha,&kctx->alpha,NULL);
851: PetscOptionsReal("-snes_ksp_ew_alpha2","alpha2","SNESKSPSetParametersEW",kctx->alpha2,&kctx->alpha2,NULL);
852: PetscOptionsReal("-snes_ksp_ew_threshold","0 < threshold < 1","SNESKSPSetParametersEW",kctx->threshold,&kctx->threshold,NULL);
854: flg = PETSC_FALSE;
855: PetscOptionsBool("-snes_monitor_cancel","Remove all monitors","SNESMonitorCancel",flg,&flg,&set);
856: if (set && flg) {SNESMonitorCancel(snes);}
858: SNESMonitorSetFromOptions(snes,"-snes_monitor","Monitor norm of function","SNESMonitorDefault",SNESMonitorDefault,NULL);
859: SNESMonitorSetFromOptions(snes,"-snes_monitor_short","Monitor norm of function with fewer digits","SNESMonitorDefaultShort",SNESMonitorDefaultShort,NULL);
860: SNESMonitorSetFromOptions(snes,"-snes_monitor_range","Monitor range of elements of function","SNESMonitorRange",SNESMonitorRange,NULL);
862: SNESMonitorSetFromOptions(snes,"-snes_monitor_ratio","Monitor ratios of the norm of function for consecutive steps","SNESMonitorRatio",SNESMonitorRatio,SNESMonitorRatioSetUp);
863: SNESMonitorSetFromOptions(snes,"-snes_monitor_field","Monitor norm of function (split into fields)","SNESMonitorDefaultField",SNESMonitorDefaultField,NULL);
864: SNESMonitorSetFromOptions(snes,"-snes_monitor_solution","View solution at each iteration","SNESMonitorSolution",SNESMonitorSolution,NULL);
865: SNESMonitorSetFromOptions(snes,"-snes_monitor_solution_update","View correction at each iteration","SNESMonitorSolutionUpdate",SNESMonitorSolutionUpdate,NULL);
866: SNESMonitorSetFromOptions(snes,"-snes_monitor_residual","View residual at each iteration","SNESMonitorResidual",SNESMonitorResidual,NULL);
867: SNESMonitorSetFromOptions(snes,"-snes_monitor_jacupdate_spectrum","Print the change in the spectrum of the Jacobian","SNESMonitorJacUpdateSpectrum",SNESMonitorJacUpdateSpectrum,NULL);
868: SNESMonitorSetFromOptions(snes,"-snes_monitor_fields","Monitor norm of function per field","SNESMonitorSet",SNESMonitorFields,NULL);
870: PetscOptionsString("-snes_monitor_python","Use Python function","SNESMonitorSet",0,monfilename,PETSC_MAX_PATH_LEN,&flg);
871: if (flg) {PetscPythonMonitorSet((PetscObject)snes,monfilename);}
874: flg = PETSC_FALSE;
875: PetscOptionsBool("-snes_monitor_lg_residualnorm","Plot function norm at each iteration","SNESMonitorLGResidualNorm",flg,&flg,NULL);
876: if (flg) {
877: PetscDrawLG ctx;
879: SNESMonitorLGCreate(PetscObjectComm((PetscObject)snes),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,400,300,&ctx);
880: SNESMonitorSet(snes,SNESMonitorLGResidualNorm,ctx,(PetscErrorCode (*)(void**))PetscDrawLGDestroy);
881: }
882: flg = PETSC_FALSE;
883: PetscOptionsBool("-snes_monitor_lg_range","Plot function range at each iteration","SNESMonitorLGRange",flg,&flg,NULL);
884: if (flg) {
885: PetscViewer ctx;
887: PetscViewerDrawOpen(PetscObjectComm((PetscObject)snes),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,400,300,&ctx);
888: SNESMonitorSet(snes,SNESMonitorLGRange,ctx,(PetscErrorCode (*)(void**))PetscViewerDestroy);
889: }
893: flg = PETSC_FALSE;
894: PetscOptionsBool("-snes_fd","Use finite differences (slow) to compute Jacobian","SNESComputeJacobianDefault",flg,&flg,NULL);
895: if (flg) {
896: void *functx;
897: DM dm;
898: DMSNES sdm;
899: SNESGetDM(snes,&dm);
900: DMGetDMSNES(dm,&sdm);
901: sdm->jacobianctx = NULL;
902: SNESGetFunction(snes,NULL,NULL,&functx);
903: SNESSetJacobian(snes,snes->jacobian,snes->jacobian_pre,SNESComputeJacobianDefault,functx);
904: PetscInfo(snes,"Setting default finite difference Jacobian matrix\n");
905: }
907: flg = PETSC_FALSE;
908: PetscOptionsBool("-snes_fd_function","Use finite differences (slow) to compute function from user objective","SNESObjectiveComputeFunctionDefaultFD",flg,&flg,NULL);
909: if (flg) {
910: SNESSetFunction(snes,NULL,SNESObjectiveComputeFunctionDefaultFD,NULL);
911: }
913: flg = PETSC_FALSE;
914: PetscOptionsBool("-snes_fd_color","Use finite differences with coloring to compute Jacobian","SNESComputeJacobianDefaultColor",flg,&flg,NULL);
915: if (flg) {
916: DM dm;
917: DMSNES sdm;
918: SNESGetDM(snes,&dm);
919: DMGetDMSNES(dm,&sdm);
920: sdm->jacobianctx = NULL;
921: SNESSetJacobian(snes,snes->jacobian,snes->jacobian_pre,SNESComputeJacobianDefaultColor,0);
922: PetscInfo(snes,"Setting default finite difference coloring Jacobian matrix\n");
923: }
925: flg = PETSC_FALSE;
926: PetscOptionsBool("-snes_mf_operator","Use a Matrix-Free Jacobian with user-provided preconditioner matrix","SNESSetUseMatrixFree",PETSC_FALSE,&snes->mf_operator,&flg);
927: if (flg && snes->mf_operator) {
928: snes->mf_operator = PETSC_TRUE;
929: snes->mf = PETSC_TRUE;
930: }
931: flg = PETSC_FALSE;
932: PetscOptionsBool("-snes_mf","Use a Matrix-Free Jacobian with no preconditioner matrix","SNESSetUseMatrixFree",PETSC_FALSE,&snes->mf,&flg);
933: if (!flg && snes->mf_operator) snes->mf = PETSC_TRUE;
934: PetscOptionsInt("-snes_mf_version","Matrix-Free routines version 1 or 2","None",snes->mf_version,&snes->mf_version,0);
936: flg = PETSC_FALSE;
937: SNESGetNPCSide(snes,&pcside);
938: PetscOptionsEnum("-snes_npc_side","SNES nonlinear preconditioner side","SNESSetNPCSide",PCSides,(PetscEnum)pcside,(PetscEnum*)&pcside,&flg);
939: if (flg) {SNESSetNPCSide(snes,pcside);}
941: #if defined(PETSC_HAVE_SAWS)
942: /*
943: Publish convergence information using SAWs
944: */
945: flg = PETSC_FALSE;
946: PetscOptionsBool("-snes_monitor_saws","Publish SNES progress using SAWs","SNESMonitorSet",flg,&flg,NULL);
947: if (flg) {
948: void *ctx;
949: SNESMonitorSAWsCreate(snes,&ctx);
950: SNESMonitorSet(snes,SNESMonitorSAWs,ctx,SNESMonitorSAWsDestroy);
951: }
952: #endif
953: #if defined(PETSC_HAVE_SAWS)
954: {
955: PetscBool set;
956: flg = PETSC_FALSE;
957: PetscOptionsBool("-snes_saws_block","Block for SAWs at end of SNESSolve","PetscObjectSAWsBlock",((PetscObject)snes)->amspublishblock,&flg,&set);
958: if (set) {
959: PetscObjectSAWsSetBlock((PetscObject)snes,flg);
960: }
961: }
962: #endif
964: for (i = 0; i < numberofsetfromoptions; i++) {
965: (*othersetfromoptions[i])(snes);
966: }
968: if (snes->ops->setfromoptions) {
969: (*snes->ops->setfromoptions)(PetscOptionsObject,snes);
970: }
972: /* process any options handlers added with PetscObjectAddOptionsHandler() */
973: PetscObjectProcessOptionsHandlers(PetscOptionsObject,(PetscObject)snes);
974: PetscOptionsEnd();
976: if (!snes->linesearch) {
977: SNESGetLineSearch(snes, &snes->linesearch);
978: }
979: SNESLineSearchSetFromOptions(snes->linesearch);
981: if (!snes->ksp) {SNESGetKSP(snes,&snes->ksp);}
982: KSPSetOperators(snes->ksp,snes->jacobian,snes->jacobian_pre);
983: KSPSetFromOptions(snes->ksp);
985: /* if someone has set the SNES NPC type, create it. */
986: SNESGetOptionsPrefix(snes, &optionsprefix);
987: PetscOptionsHasName(((PetscObject)snes)->options,optionsprefix, "-npc_snes_type", &pcset);
988: if (pcset && (!snes->npc)) {
989: SNESGetNPC(snes, &snes->npc);
990: }
991: snes->setfromoptionscalled++;
992: return(0);
993: }
995: /*@
996: SNESResetFromOptions - Sets various SNES and KSP parameters from user options ONLY if the SNES was previously set from options
998: Collective on SNES
1000: Input Parameter:
1001: . snes - the SNES context
1003: Level: beginner
1005: .keywords: SNES, nonlinear, set, options, database
1007: .seealso: SNESSetFromOptions(), SNESSetOptionsPrefix()
1008: @*/
1009: PetscErrorCode SNESResetFromOptions(SNES snes)
1010: {
1014: if (snes->setfromoptionscalled) {SNESSetFromOptions(snes);}
1015: return(0);
1016: }
1018: /*@C
1019: SNESSetComputeApplicationContext - Sets an optional function to compute a user-defined context for
1020: the nonlinear solvers.
1022: Logically Collective on SNES
1024: Input Parameters:
1025: + snes - the SNES context
1026: . compute - function to compute the context
1027: - destroy - function to destroy the context
1029: Level: intermediate
1031: Notes:
1032: This function is currently not available from Fortran.
1034: .keywords: SNES, nonlinear, set, application, context
1036: .seealso: SNESGetApplicationContext(), SNESSetComputeApplicationContext(), SNESGetApplicationContext()
1037: @*/
1038: PetscErrorCode SNESSetComputeApplicationContext(SNES snes,PetscErrorCode (*compute)(SNES,void**),PetscErrorCode (*destroy)(void**))
1039: {
1042: snes->ops->usercompute = compute;
1043: snes->ops->userdestroy = destroy;
1044: return(0);
1045: }
1047: /*@
1048: SNESSetApplicationContext - Sets the optional user-defined context for
1049: the nonlinear solvers.
1051: Logically Collective on SNES
1053: Input Parameters:
1054: + snes - the SNES context
1055: - usrP - optional user context
1057: Level: intermediate
1059: Fortran Notes:
1060: To use this from Fortran you must write a Fortran interface definition for this
1061: function that tells Fortran the Fortran derived data type that you are passing in as the ctx argument.
1063: .keywords: SNES, nonlinear, set, application, context
1065: .seealso: SNESGetApplicationContext()
1066: @*/
1067: PetscErrorCode SNESSetApplicationContext(SNES snes,void *usrP)
1068: {
1070: KSP ksp;
1074: SNESGetKSP(snes,&ksp);
1075: KSPSetApplicationContext(ksp,usrP);
1076: snes->user = usrP;
1077: return(0);
1078: }
1080: /*@
1081: SNESGetApplicationContext - Gets the user-defined context for the
1082: nonlinear solvers.
1084: Not Collective
1086: Input Parameter:
1087: . snes - SNES context
1089: Output Parameter:
1090: . usrP - user context
1092: Fortran Notes:
1093: To use this from Fortran you must write a Fortran interface definition for this
1094: function that tells Fortran the Fortran derived data type that you are passing in as the ctx argument.
1096: Level: intermediate
1098: .keywords: SNES, nonlinear, get, application, context
1100: .seealso: SNESSetApplicationContext()
1101: @*/
1102: PetscErrorCode SNESGetApplicationContext(SNES snes,void *usrP)
1103: {
1106: *(void**)usrP = snes->user;
1107: return(0);
1108: }
1110: /*@
1111: SNESSetUseMatrixFree - indicates that SNES should use matrix free finite difference matrix vector products internally to apply
1112: the Jacobian.
1114: Collective on SNES
1116: Input Parameters:
1117: + snes - SNES context
1118: . mf - use matrix-free for both the Amat and Pmat used by SNESSetJacobian(), both the Amat and Pmat set in SNESSetJacobian() will be ignored
1119: - mf_operator - use matrix-free only for the Amat used by SNESSetJacobian(), this means the user provided Pmat will continue to be used
1121: Options Database:
1122: + -snes_mf - use matrix free for both the mat and pmat operator
1123: - -snes_mf_operator - use matrix free only for the mat operator
1125: Level: intermediate
1127: .keywords: SNES, nonlinear, get, iteration, number,
1129: .seealso: SNESGetUseMatrixFree(), MatCreateSNESMF()
1130: @*/
1131: PetscErrorCode SNESSetUseMatrixFree(SNES snes,PetscBool mf_operator,PetscBool mf)
1132: {
1137: if (mf && !mf_operator) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_INCOMP,"If using mf must also use mf_operator");
1138: snes->mf = mf;
1139: snes->mf_operator = mf_operator;
1140: return(0);
1141: }
1143: /*@
1144: SNESGetUseMatrixFree - indicates if the SNES uses matrix free finite difference matrix vector products to apply
1145: the Jacobian.
1147: Collective on SNES
1149: Input Parameter:
1150: . snes - SNES context
1152: Output Parameters:
1153: + mf - use matrix-free for both the Amat and Pmat used by SNESSetJacobian(), both the Amat and Pmat set in SNESSetJacobian() will be ignored
1154: - mf_operator - use matrix-free only for the Amat used by SNESSetJacobian(), this means the user provided Pmat will continue to be used
1156: Options Database:
1157: + -snes_mf - use matrix free for both the mat and pmat operator
1158: - -snes_mf_operator - use matrix free only for the mat operator
1160: Level: intermediate
1162: .keywords: SNES, nonlinear, get, iteration, number,
1164: .seealso: SNESSetUseMatrixFree(), MatCreateSNESMF()
1165: @*/
1166: PetscErrorCode SNESGetUseMatrixFree(SNES snes,PetscBool *mf_operator,PetscBool *mf)
1167: {
1170: if (mf) *mf = snes->mf;
1171: if (mf_operator) *mf_operator = snes->mf_operator;
1172: return(0);
1173: }
1175: /*@
1176: SNESGetIterationNumber - Gets the number of nonlinear iterations completed
1177: at this time.
1179: Not Collective
1181: Input Parameter:
1182: . snes - SNES context
1184: Output Parameter:
1185: . iter - iteration number
1187: Notes:
1188: For example, during the computation of iteration 2 this would return 1.
1190: This is useful for using lagged Jacobians (where one does not recompute the
1191: Jacobian at each SNES iteration). For example, the code
1192: .vb
1193: SNESGetIterationNumber(snes,&it);
1194: if (!(it % 2)) {
1195: [compute Jacobian here]
1196: }
1197: .ve
1198: can be used in your ComputeJacobian() function to cause the Jacobian to be
1199: recomputed every second SNES iteration.
1201: After the SNES solve is complete this will return the number of nonlinear iterations used.
1203: Level: intermediate
1205: .keywords: SNES, nonlinear, get, iteration, number,
1207: .seealso: SNESGetLinearSolveIterations()
1208: @*/
1209: PetscErrorCode SNESGetIterationNumber(SNES snes,PetscInt *iter)
1210: {
1214: *iter = snes->iter;
1215: return(0);
1216: }
1218: /*@
1219: SNESSetIterationNumber - Sets the current iteration number.
1221: Not Collective
1223: Input Parameter:
1224: . snes - SNES context
1225: . iter - iteration number
1227: Level: developer
1229: .keywords: SNES, nonlinear, set, iteration, number,
1231: .seealso: SNESGetLinearSolveIterations()
1232: @*/
1233: PetscErrorCode SNESSetIterationNumber(SNES snes,PetscInt iter)
1234: {
1239: PetscObjectSAWsTakeAccess((PetscObject)snes);
1240: snes->iter = iter;
1241: PetscObjectSAWsGrantAccess((PetscObject)snes);
1242: return(0);
1243: }
1245: /*@
1246: SNESGetNonlinearStepFailures - Gets the number of unsuccessful steps
1247: attempted by the nonlinear solver.
1249: Not Collective
1251: Input Parameter:
1252: . snes - SNES context
1254: Output Parameter:
1255: . nfails - number of unsuccessful steps attempted
1257: Notes:
1258: This counter is reset to zero for each successive call to SNESSolve().
1260: Level: intermediate
1262: .keywords: SNES, nonlinear, get, number, unsuccessful, steps
1264: .seealso: SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures(), SNESGetLinearSolveFailures(),
1265: SNESSetMaxNonlinearStepFailures(), SNESGetMaxNonlinearStepFailures()
1266: @*/
1267: PetscErrorCode SNESGetNonlinearStepFailures(SNES snes,PetscInt *nfails)
1268: {
1272: *nfails = snes->numFailures;
1273: return(0);
1274: }
1276: /*@
1277: SNESSetMaxNonlinearStepFailures - Sets the maximum number of unsuccessful steps
1278: attempted by the nonlinear solver before it gives up.
1280: Not Collective
1282: Input Parameters:
1283: + snes - SNES context
1284: - maxFails - maximum of unsuccessful steps
1286: Level: intermediate
1288: .keywords: SNES, nonlinear, set, maximum, unsuccessful, steps
1290: .seealso: SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures(), SNESGetLinearSolveFailures(),
1291: SNESGetMaxNonlinearStepFailures(), SNESGetNonlinearStepFailures()
1292: @*/
1293: PetscErrorCode SNESSetMaxNonlinearStepFailures(SNES snes, PetscInt maxFails)
1294: {
1297: snes->maxFailures = maxFails;
1298: return(0);
1299: }
1301: /*@
1302: SNESGetMaxNonlinearStepFailures - Gets the maximum number of unsuccessful steps
1303: attempted by the nonlinear solver before it gives up.
1305: Not Collective
1307: Input Parameter:
1308: . snes - SNES context
1310: Output Parameter:
1311: . maxFails - maximum of unsuccessful steps
1313: Level: intermediate
1315: .keywords: SNES, nonlinear, get, maximum, unsuccessful, steps
1317: .seealso: SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures(), SNESGetLinearSolveFailures(),
1318: SNESSetMaxNonlinearStepFailures(), SNESGetNonlinearStepFailures()
1320: @*/
1321: PetscErrorCode SNESGetMaxNonlinearStepFailures(SNES snes, PetscInt *maxFails)
1322: {
1326: *maxFails = snes->maxFailures;
1327: return(0);
1328: }
1330: /*@
1331: SNESGetNumberFunctionEvals - Gets the number of user provided function evaluations
1332: done by SNES.
1334: Not Collective
1336: Input Parameter:
1337: . snes - SNES context
1339: Output Parameter:
1340: . nfuncs - number of evaluations
1342: Level: intermediate
1344: Notes:
1345: Reset every time SNESSolve is called unless SNESSetCountersReset() is used.
1347: .keywords: SNES, nonlinear, get, maximum, unsuccessful, steps
1349: .seealso: SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures(), SNESGetLinearSolveFailures(), SNESSetCountersReset()
1350: @*/
1351: PetscErrorCode SNESGetNumberFunctionEvals(SNES snes, PetscInt *nfuncs)
1352: {
1356: *nfuncs = snes->nfuncs;
1357: return(0);
1358: }
1360: /*@
1361: SNESGetLinearSolveFailures - Gets the number of failed (non-converged)
1362: linear solvers.
1364: Not Collective
1366: Input Parameter:
1367: . snes - SNES context
1369: Output Parameter:
1370: . nfails - number of failed solves
1372: Level: intermediate
1374: Options Database Keys:
1375: . -snes_max_linear_solve_fail <num> - The number of failures before the solve is terminated
1377: Notes:
1378: This counter is reset to zero for each successive call to SNESSolve().
1380: .keywords: SNES, nonlinear, get, number, unsuccessful, steps
1382: .seealso: SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures()
1383: @*/
1384: PetscErrorCode SNESGetLinearSolveFailures(SNES snes,PetscInt *nfails)
1385: {
1389: *nfails = snes->numLinearSolveFailures;
1390: return(0);
1391: }
1393: /*@
1394: SNESSetMaxLinearSolveFailures - the number of failed linear solve attempts
1395: allowed before SNES returns with a diverged reason of SNES_DIVERGED_LINEAR_SOLVE
1397: Logically Collective on SNES
1399: Input Parameters:
1400: + snes - SNES context
1401: - maxFails - maximum allowed linear solve failures
1403: Level: intermediate
1405: Options Database Keys:
1406: . -snes_max_linear_solve_fail <num> - The number of failures before the solve is terminated
1408: Notes:
1409: By default this is 0; that is SNES returns on the first failed linear solve
1411: .keywords: SNES, nonlinear, set, maximum, unsuccessful, steps
1413: .seealso: SNESGetLinearSolveFailures(), SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations()
1414: @*/
1415: PetscErrorCode SNESSetMaxLinearSolveFailures(SNES snes, PetscInt maxFails)
1416: {
1420: snes->maxLinearSolveFailures = maxFails;
1421: return(0);
1422: }
1424: /*@
1425: SNESGetMaxLinearSolveFailures - gets the maximum number of linear solve failures that
1426: are allowed before SNES terminates
1428: Not Collective
1430: Input Parameter:
1431: . snes - SNES context
1433: Output Parameter:
1434: . maxFails - maximum of unsuccessful solves allowed
1436: Level: intermediate
1438: Notes:
1439: By default this is 1; that is SNES returns on the first failed linear solve
1441: .keywords: SNES, nonlinear, get, maximum, unsuccessful, steps
1443: .seealso: SNESGetLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures(),
1444: @*/
1445: PetscErrorCode SNESGetMaxLinearSolveFailures(SNES snes, PetscInt *maxFails)
1446: {
1450: *maxFails = snes->maxLinearSolveFailures;
1451: return(0);
1452: }
1454: /*@
1455: SNESGetLinearSolveIterations - Gets the total number of linear iterations
1456: used by the nonlinear solver.
1458: Not Collective
1460: Input Parameter:
1461: . snes - SNES context
1463: Output Parameter:
1464: . lits - number of linear iterations
1466: Notes:
1467: This counter is reset to zero for each successive call to SNESSolve() unless SNESSetCountersReset() is used.
1469: If the linear solver fails inside the SNESSolve() the iterations for that call to the linear solver are not included. If you wish to count them
1470: then call KSPGetIterationNumber() after the failed solve.
1472: Level: intermediate
1474: .keywords: SNES, nonlinear, get, number, linear, iterations
1476: .seealso: SNESGetIterationNumber(), SNESGetLinearSolveFailures(), SNESGetMaxLinearSolveFailures(), SNESSetCountersReset()
1477: @*/
1478: PetscErrorCode SNESGetLinearSolveIterations(SNES snes,PetscInt *lits)
1479: {
1483: *lits = snes->linear_its;
1484: return(0);
1485: }
1487: /*@
1488: SNESSetCountersReset - Sets whether or not the counters for linear iterations and function evaluations
1489: are reset every time SNESSolve() is called.
1491: Logically Collective on SNES
1493: Input Parameter:
1494: + snes - SNES context
1495: - reset - whether to reset the counters or not
1497: Notes:
1498: This defaults to PETSC_TRUE
1500: Level: developer
1502: .keywords: SNES, nonlinear, set, reset, number, linear, iterations
1504: .seealso: SNESGetNumberFunctionEvals(), SNESGetLinearSolveIterations(), SNESGetNPC()
1505: @*/
1506: PetscErrorCode SNESSetCountersReset(SNES snes,PetscBool reset)
1507: {
1511: snes->counters_reset = reset;
1512: return(0);
1513: }
1516: /*@
1517: SNESSetKSP - Sets a KSP context for the SNES object to use
1519: Not Collective, but the SNES and KSP objects must live on the same MPI_Comm
1521: Input Parameters:
1522: + snes - the SNES context
1523: - ksp - the KSP context
1525: Notes:
1526: The SNES object already has its KSP object, you can obtain with SNESGetKSP()
1527: so this routine is rarely needed.
1529: The KSP object that is already in the SNES object has its reference count
1530: decreased by one.
1532: Level: developer
1534: .keywords: SNES, nonlinear, get, KSP, context
1536: .seealso: KSPGetPC(), SNESCreate(), KSPCreate(), SNESSetKSP()
1537: @*/
1538: PetscErrorCode SNESSetKSP(SNES snes,KSP ksp)
1539: {
1546: PetscObjectReference((PetscObject)ksp);
1547: if (snes->ksp) {PetscObjectDereference((PetscObject)snes->ksp);}
1548: snes->ksp = ksp;
1549: return(0);
1550: }
1552: /* -----------------------------------------------------------*/
1553: /*@
1554: SNESCreate - Creates a nonlinear solver context.
1556: Collective on MPI_Comm
1558: Input Parameters:
1559: . comm - MPI communicator
1561: Output Parameter:
1562: . outsnes - the new SNES context
1564: Options Database Keys:
1565: + -snes_mf - Activates default matrix-free Jacobian-vector products,
1566: and no preconditioning matrix
1567: . -snes_mf_operator - Activates default matrix-free Jacobian-vector
1568: products, and a user-provided preconditioning matrix
1569: as set by SNESSetJacobian()
1570: - -snes_fd - Uses (slow!) finite differences to compute Jacobian
1572: Level: beginner
1574: Developer Notes:
1575: SNES always creates a KSP object even though many SNES methods do not use it. This is
1576: unfortunate and should be fixed at some point. The flag snes->usesksp indicates if the
1577: particular method does use KSP and regulates if the information about the KSP is printed
1578: in SNESView(). TSSetFromOptions() does call SNESSetFromOptions() which can lead to users being confused
1579: by help messages about meaningless SNES options.
1581: SNES always creates the snes->kspconvctx even though it is used by only one type. This should
1582: be fixed.
1584: .keywords: SNES, nonlinear, create, context
1586: .seealso: SNESSolve(), SNESDestroy(), SNES, SNESSetLagPreconditioner()
1588: @*/
1589: PetscErrorCode SNESCreate(MPI_Comm comm,SNES *outsnes)
1590: {
1592: SNES snes;
1593: SNESKSPEW *kctx;
1597: *outsnes = NULL;
1598: SNESInitializePackage();
1600: PetscHeaderCreate(snes,SNES_CLASSID,"SNES","Nonlinear solver","SNES",comm,SNESDestroy,SNESView);
1602: snes->ops->converged = SNESConvergedDefault;
1603: snes->usesksp = PETSC_TRUE;
1604: snes->tolerancesset = PETSC_FALSE;
1605: snes->max_its = 50;
1606: snes->max_funcs = 10000;
1607: snes->norm = 0.0;
1608: snes->normschedule = SNES_NORM_ALWAYS;
1609: snes->functype = SNES_FUNCTION_DEFAULT;
1610: #if defined(PETSC_USE_REAL_SINGLE)
1611: snes->rtol = 1.e-5;
1612: #else
1613: snes->rtol = 1.e-8;
1614: #endif
1615: snes->ttol = 0.0;
1616: #if defined(PETSC_USE_REAL_SINGLE)
1617: snes->abstol = 1.e-25;
1618: #else
1619: snes->abstol = 1.e-50;
1620: #endif
1621: #if defined(PETSC_USE_REAL_SINGLE)
1622: snes->stol = 1.e-5;
1623: #else
1624: snes->stol = 1.e-8;
1625: #endif
1626: #if defined(PETSC_USE_REAL_SINGLE)
1627: snes->deltatol = 1.e-6;
1628: #else
1629: snes->deltatol = 1.e-12;
1630: #endif
1631: snes->divtol = 1.e4;
1632: snes->rnorm0 = 0;
1633: snes->nfuncs = 0;
1634: snes->numFailures = 0;
1635: snes->maxFailures = 1;
1636: snes->linear_its = 0;
1637: snes->lagjacobian = 1;
1638: snes->jac_iter = 0;
1639: snes->lagjac_persist = PETSC_FALSE;
1640: snes->lagpreconditioner = 1;
1641: snes->pre_iter = 0;
1642: snes->lagpre_persist = PETSC_FALSE;
1643: snes->numbermonitors = 0;
1644: snes->data = 0;
1645: snes->setupcalled = PETSC_FALSE;
1646: snes->ksp_ewconv = PETSC_FALSE;
1647: snes->nwork = 0;
1648: snes->work = 0;
1649: snes->nvwork = 0;
1650: snes->vwork = 0;
1651: snes->conv_hist_len = 0;
1652: snes->conv_hist_max = 0;
1653: snes->conv_hist = NULL;
1654: snes->conv_hist_its = NULL;
1655: snes->conv_hist_reset = PETSC_TRUE;
1656: snes->counters_reset = PETSC_TRUE;
1657: snes->vec_func_init_set = PETSC_FALSE;
1658: snes->reason = SNES_CONVERGED_ITERATING;
1659: snes->npcside = PC_RIGHT;
1660: snes->setfromoptionscalled = 0;
1662: snes->mf = PETSC_FALSE;
1663: snes->mf_operator = PETSC_FALSE;
1664: snes->mf_version = 1;
1666: snes->numLinearSolveFailures = 0;
1667: snes->maxLinearSolveFailures = 1;
1669: snes->vizerotolerance = 1.e-8;
1671: /* Set this to true if the implementation of SNESSolve_XXX does compute the residual at the final solution. */
1672: snes->alwayscomputesfinalresidual = PETSC_FALSE;
1674: /* Create context to compute Eisenstat-Walker relative tolerance for KSP */
1675: PetscNewLog(snes,&kctx);
1677: snes->kspconvctx = (void*)kctx;
1678: kctx->version = 2;
1679: kctx->rtol_0 = .3; /* Eisenstat and Walker suggest rtol_0=.5, but
1680: this was too large for some test cases */
1681: kctx->rtol_last = 0.0;
1682: kctx->rtol_max = .9;
1683: kctx->gamma = 1.0;
1684: kctx->alpha = .5*(1.0 + PetscSqrtReal(5.0));
1685: kctx->alpha2 = kctx->alpha;
1686: kctx->threshold = .1;
1687: kctx->lresid_last = 0.0;
1688: kctx->norm_last = 0.0;
1690: *outsnes = snes;
1691: return(0);
1692: }
1694: /*MC
1695: SNESFunction - Functional form used to convey the nonlinear function to be solved by SNES
1697: Synopsis:
1698: #include "petscsnes.h"
1699: PetscErrorCode SNESFunction(SNES snes,Vec x,Vec f,void *ctx);
1701: Input Parameters:
1702: + snes - the SNES context
1703: . x - state at which to evaluate residual
1704: - ctx - optional user-defined function context, passed in with SNESSetFunction()
1706: Output Parameter:
1707: . f - vector to put residual (function value)
1709: Level: intermediate
1711: .seealso: SNESSetFunction(), SNESGetFunction()
1712: M*/
1714: /*@C
1715: SNESSetFunction - Sets the function evaluation routine and function
1716: vector for use by the SNES routines in solving systems of nonlinear
1717: equations.
1719: Logically Collective on SNES
1721: Input Parameters:
1722: + snes - the SNES context
1723: . r - vector to store function value
1724: . f - function evaluation routine; see SNESFunction for calling sequence details
1725: - ctx - [optional] user-defined context for private data for the
1726: function evaluation routine (may be NULL)
1728: Notes:
1729: The Newton-like methods typically solve linear systems of the form
1730: $ f'(x) x = -f(x),
1731: where f'(x) denotes the Jacobian matrix and f(x) is the function.
1733: Level: beginner
1735: .keywords: SNES, nonlinear, set, function
1737: .seealso: SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESSetPicard(), SNESFunction
1738: @*/
1739: PetscErrorCode SNESSetFunction(SNES snes,Vec r,PetscErrorCode (*f)(SNES,Vec,Vec,void*),void *ctx)
1740: {
1742: DM dm;
1746: if (r) {
1749: PetscObjectReference((PetscObject)r);
1750: VecDestroy(&snes->vec_func);
1752: snes->vec_func = r;
1753: }
1754: SNESGetDM(snes,&dm);
1755: DMSNESSetFunction(dm,f,ctx);
1756: return(0);
1757: }
1760: /*@C
1761: SNESSetInitialFunction - Sets the function vector to be used as the
1762: function norm at the initialization of the method. In some
1763: instances, the user has precomputed the function before calling
1764: SNESSolve. This function allows one to avoid a redundant call
1765: to SNESComputeFunction in that case.
1767: Logically Collective on SNES
1769: Input Parameters:
1770: + snes - the SNES context
1771: - f - vector to store function value
1773: Notes:
1774: This should not be modified during the solution procedure.
1776: This is used extensively in the SNESFAS hierarchy and in nonlinear preconditioning.
1778: Level: developer
1780: .keywords: SNES, nonlinear, set, function
1782: .seealso: SNESSetFunction(), SNESComputeFunction(), SNESSetInitialFunctionNorm()
1783: @*/
1784: PetscErrorCode SNESSetInitialFunction(SNES snes, Vec f)
1785: {
1787: Vec vec_func;
1793: if (snes->npcside== PC_LEFT && snes->functype == SNES_FUNCTION_PRECONDITIONED) {
1794: snes->vec_func_init_set = PETSC_FALSE;
1795: return(0);
1796: }
1797: SNESGetFunction(snes,&vec_func,NULL,NULL);
1798: VecCopy(f, vec_func);
1800: snes->vec_func_init_set = PETSC_TRUE;
1801: return(0);
1802: }
1804: /*@
1805: SNESSetNormSchedule - Sets the SNESNormSchedule used in covergence and monitoring
1806: of the SNES method.
1808: Logically Collective on SNES
1810: Input Parameters:
1811: + snes - the SNES context
1812: - normschedule - the frequency of norm computation
1814: Options Database Key:
1815: . -snes_norm_schedule <none, always, initialonly, finalonly, initalfinalonly>
1817: Notes:
1818: Only certain SNES methods support certain SNESNormSchedules. Most require evaluation
1819: of the nonlinear function and the taking of its norm at every iteration to
1820: even ensure convergence at all. However, methods such as custom Gauss-Seidel methods
1821: (SNESNGS) and the like do not require the norm of the function to be computed, and therfore
1822: may either be monitored for convergence or not. As these are often used as nonlinear
1823: preconditioners, monitoring the norm of their error is not a useful enterprise within
1824: their solution.
1826: Level: developer
1828: .keywords: SNES, nonlinear, set, function, norm, type
1830: .seealso: SNESGetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
1831: @*/
1832: PetscErrorCode SNESSetNormSchedule(SNES snes, SNESNormSchedule normschedule)
1833: {
1836: snes->normschedule = normschedule;
1837: return(0);
1838: }
1841: /*@
1842: SNESGetNormSchedule - Gets the SNESNormSchedule used in covergence and monitoring
1843: of the SNES method.
1845: Logically Collective on SNES
1847: Input Parameters:
1848: + snes - the SNES context
1849: - normschedule - the type of the norm used
1851: Level: advanced
1853: .keywords: SNES, nonlinear, set, function, norm, type
1855: .seealso: SNESSetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
1856: @*/
1857: PetscErrorCode SNESGetNormSchedule(SNES snes, SNESNormSchedule *normschedule)
1858: {
1861: *normschedule = snes->normschedule;
1862: return(0);
1863: }
1866: /*@
1867: SNESSetFunctionNorm - Sets the last computed residual norm.
1869: Logically Collective on SNES
1871: Input Parameters:
1872: + snes - the SNES context
1874: - normschedule - the frequency of norm computation
1876: Level: developer
1878: .keywords: SNES, nonlinear, set, function, norm, type
1879: .seealso: SNESGetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
1880: @*/
1881: PetscErrorCode SNESSetFunctionNorm(SNES snes, PetscReal norm)
1882: {
1885: snes->norm = norm;
1886: return(0);
1887: }
1889: /*@
1890: SNESGetFunctionNorm - Gets the last computed norm of the residual
1892: Not Collective
1894: Input Parameter:
1895: . snes - the SNES context
1897: Output Parameter:
1898: . norm - the last computed residual norm
1900: Level: developer
1902: .keywords: SNES, nonlinear, set, function, norm, type
1903: .seealso: SNESSetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
1904: @*/
1905: PetscErrorCode SNESGetFunctionNorm(SNES snes, PetscReal *norm)
1906: {
1910: *norm = snes->norm;
1911: return(0);
1912: }
1914: /*@C
1915: SNESSetFunctionType - Sets the SNESNormSchedule used in covergence and monitoring
1916: of the SNES method.
1918: Logically Collective on SNES
1920: Input Parameters:
1921: + snes - the SNES context
1922: - normschedule - the frequency of norm computation
1924: Notes:
1925: Only certain SNES methods support certain SNESNormSchedules. Most require evaluation
1926: of the nonlinear function and the taking of its norm at every iteration to
1927: even ensure convergence at all. However, methods such as custom Gauss-Seidel methods
1928: (SNESNGS) and the like do not require the norm of the function to be computed, and therfore
1929: may either be monitored for convergence or not. As these are often used as nonlinear
1930: preconditioners, monitoring the norm of their error is not a useful enterprise within
1931: their solution.
1933: Level: developer
1935: .keywords: SNES, nonlinear, set, function, norm, type
1937: .seealso: SNESGetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
1938: @*/
1939: PetscErrorCode SNESSetFunctionType(SNES snes, SNESFunctionType type)
1940: {
1943: snes->functype = type;
1944: return(0);
1945: }
1948: /*@C
1949: SNESGetFunctionType - Gets the SNESNormSchedule used in covergence and monitoring
1950: of the SNES method.
1952: Logically Collective on SNES
1954: Input Parameters:
1955: + snes - the SNES context
1956: - normschedule - the type of the norm used
1958: Level: advanced
1960: .keywords: SNES, nonlinear, set, function, norm, type
1962: .seealso: SNESSetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
1963: @*/
1964: PetscErrorCode SNESGetFunctionType(SNES snes, SNESFunctionType *type)
1965: {
1968: *type = snes->functype;
1969: return(0);
1970: }
1972: /*MC
1973: SNESNGSFunction - function used to convey a Gauss-Seidel sweep on the nonlinear function
1975: Synopsis:
1976: #include <petscsnes.h>
1977: $ SNESNGSFunction(SNES snes,Vec x,Vec b,void *ctx);
1979: + X - solution vector
1980: . B - RHS vector
1981: - ctx - optional user-defined Gauss-Seidel context
1983: Level: intermediate
1985: .seealso: SNESSetNGS(), SNESGetNGS()
1986: M*/
1988: /*@C
1989: SNESSetNGS - Sets the user nonlinear Gauss-Seidel routine for
1990: use with composed nonlinear solvers.
1992: Input Parameters:
1993: + snes - the SNES context
1994: . f - function evaluation routine to apply Gauss-Seidel see SNESNGSFunction
1995: - ctx - [optional] user-defined context for private data for the
1996: smoother evaluation routine (may be NULL)
1998: Notes:
1999: The NGS routines are used by the composed nonlinear solver to generate
2000: a problem appropriate update to the solution, particularly FAS.
2002: Level: intermediate
2004: .keywords: SNES, nonlinear, set, Gauss-Seidel
2006: .seealso: SNESGetFunction(), SNESComputeNGS()
2007: @*/
2008: PetscErrorCode SNESSetNGS(SNES snes,PetscErrorCode (*f)(SNES,Vec,Vec,void*),void *ctx)
2009: {
2011: DM dm;
2015: SNESGetDM(snes,&dm);
2016: DMSNESSetNGS(dm,f,ctx);
2017: return(0);
2018: }
2020: PetscErrorCode SNESPicardComputeFunction(SNES snes,Vec x,Vec f,void *ctx)
2021: {
2023: DM dm;
2024: DMSNES sdm;
2027: SNESGetDM(snes,&dm);
2028: DMGetDMSNES(dm,&sdm);
2029: if (!sdm->ops->computepfunction) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Must call SNESSetPicard() to provide Picard function.");
2030: if (!sdm->ops->computepjacobian) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Must call SNESSetPicard() to provide Picard Jacobian.");
2031: /* A(x)*x - b(x) */
2032: PetscStackPush("SNES Picard user function");
2033: (*sdm->ops->computepfunction)(snes,x,f,sdm->pctx);
2034: PetscStackPop;
2035: PetscStackPush("SNES Picard user Jacobian");
2036: (*sdm->ops->computepjacobian)(snes,x,snes->jacobian,snes->jacobian_pre,sdm->pctx);
2037: PetscStackPop;
2038: VecScale(f,-1.0);
2039: MatMultAdd(snes->jacobian,x,f,f);
2040: return(0);
2041: }
2043: PetscErrorCode SNESPicardComputeJacobian(SNES snes,Vec x1,Mat J,Mat B,void *ctx)
2044: {
2046: /* the jacobian matrix should be pre-filled in SNESPicardComputeFunction */
2047: return(0);
2048: }
2050: /*@C
2051: SNESSetPicard - Use SNES to solve the semilinear-system A(x) x = b(x) via a Picard type iteration (Picard linearization)
2053: Logically Collective on SNES
2055: Input Parameters:
2056: + snes - the SNES context
2057: . r - vector to store function value
2058: . b - function evaluation routine
2059: . Amat - matrix with which A(x) x - b(x) is to be computed
2060: . Pmat - matrix from which preconditioner is computed (usually the same as Amat)
2061: . J - function to compute matrix value, see SNESJacobianFunction for details on its calling sequence
2062: - ctx - [optional] user-defined context for private data for the
2063: function evaluation routine (may be NULL)
2065: Notes:
2066: We do not recomemend using this routine. It is far better to provide the nonlinear function F() and some approximation to the Jacobian and use
2067: an approximate Newton solver. This interface is provided to allow porting/testing a previous Picard based code in PETSc before converting it to approximate Newton.
2069: One can call SNESSetPicard() or SNESSetFunction() (and possibly SNESSetJacobian()) but cannot call both
2071: $ Solves the equation A(x) x = b(x) via the defect correction algorithm A(x^{n}) (x^{n+1} - x^{n}) = b(x^{n}) - A(x^{n})x^{n}
2072: $ Note that when an exact solver is used this corresponds to the "classic" Picard A(x^{n}) x^{n+1} = b(x^{n}) iteration.
2074: Run with -snes_mf_operator to solve the system with Newton's method using A(x^{n}) to construct the preconditioner.
2076: We implement the defect correction form of the Picard iteration because it converges much more generally when inexact linear solvers are used then
2077: the direct Picard iteration A(x^n) x^{n+1} = b(x^n)
2079: There is some controversity over the definition of a Picard iteration for nonlinear systems but almost everyone agrees that it involves a linear solve and some
2080: believe it is the iteration A(x^{n}) x^{n+1} = b(x^{n}) hence we use the name Picard. If anyone has an authoritative reference that defines the Picard iteration
2081: different please contact us at petsc-dev@mcs.anl.gov and we'll have an entirely new argument :-).
2083: Level: intermediate
2085: .keywords: SNES, nonlinear, set, function
2087: .seealso: SNESGetFunction(), SNESSetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESGetPicard(), SNESLineSearchPreCheckPicard(), SNESJacobianFunction
2088: @*/
2089: PetscErrorCode SNESSetPicard(SNES snes,Vec r,PetscErrorCode (*b)(SNES,Vec,Vec,void*),Mat Amat, Mat Pmat, PetscErrorCode (*J)(SNES,Vec,Mat,Mat,void*),void *ctx)
2090: {
2092: DM dm;
2096: SNESGetDM(snes, &dm);
2097: DMSNESSetPicard(dm,b,J,ctx);
2098: SNESSetFunction(snes,r,SNESPicardComputeFunction,ctx);
2099: SNESSetJacobian(snes,Amat,Pmat,SNESPicardComputeJacobian,ctx);
2100: return(0);
2101: }
2103: /*@C
2104: SNESGetPicard - Returns the context for the Picard iteration
2106: Not Collective, but Vec is parallel if SNES is parallel. Collective if Vec is requested, but has not been created yet.
2108: Input Parameter:
2109: . snes - the SNES context
2111: Output Parameter:
2112: + r - the function (or NULL)
2113: . f - the function (or NULL); see SNESFunction for calling sequence details
2114: . Amat - the matrix used to defined the operation A(x) x - b(x) (or NULL)
2115: . Pmat - the matrix from which the preconditioner will be constructed (or NULL)
2116: . J - the function for matrix evaluation (or NULL); see SNESJacobianFunction for calling sequence details
2117: - ctx - the function context (or NULL)
2119: Level: advanced
2121: .keywords: SNES, nonlinear, get, function
2123: .seealso: SNESSetPicard(), SNESGetFunction(), SNESGetJacobian(), SNESGetDM(), SNESFunction, SNESJacobianFunction
2124: @*/
2125: PetscErrorCode SNESGetPicard(SNES snes,Vec *r,PetscErrorCode (**f)(SNES,Vec,Vec,void*),Mat *Amat, Mat *Pmat, PetscErrorCode (**J)(SNES,Vec,Mat,Mat,void*),void **ctx)
2126: {
2128: DM dm;
2132: SNESGetFunction(snes,r,NULL,NULL);
2133: SNESGetJacobian(snes,Amat,Pmat,NULL,NULL);
2134: SNESGetDM(snes,&dm);
2135: DMSNESGetPicard(dm,f,J,ctx);
2136: return(0);
2137: }
2139: /*@C
2140: SNESSetComputeInitialGuess - Sets a routine used to compute an initial guess for the problem
2142: Logically Collective on SNES
2144: Input Parameters:
2145: + snes - the SNES context
2146: . func - function evaluation routine
2147: - ctx - [optional] user-defined context for private data for the
2148: function evaluation routine (may be NULL)
2150: Calling sequence of func:
2151: $ func (SNES snes,Vec x,void *ctx);
2153: . f - function vector
2154: - ctx - optional user-defined function context
2156: Level: intermediate
2158: .keywords: SNES, nonlinear, set, function
2160: .seealso: SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian()
2161: @*/
2162: PetscErrorCode SNESSetComputeInitialGuess(SNES snes,PetscErrorCode (*func)(SNES,Vec,void*),void *ctx)
2163: {
2166: if (func) snes->ops->computeinitialguess = func;
2167: if (ctx) snes->initialguessP = ctx;
2168: return(0);
2169: }
2171: /* --------------------------------------------------------------- */
2172: /*@C
2173: SNESGetRhs - Gets the vector for solving F(x) = rhs. If rhs is not set
2174: it assumes a zero right hand side.
2176: Logically Collective on SNES
2178: Input Parameter:
2179: . snes - the SNES context
2181: Output Parameter:
2182: . rhs - the right hand side vector or NULL if the right hand side vector is null
2184: Level: intermediate
2186: .keywords: SNES, nonlinear, get, function, right hand side
2188: .seealso: SNESGetSolution(), SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESSetFunction()
2189: @*/
2190: PetscErrorCode SNESGetRhs(SNES snes,Vec *rhs)
2191: {
2195: *rhs = snes->vec_rhs;
2196: return(0);
2197: }
2199: /*@
2200: SNESComputeFunction - Calls the function that has been set with SNESSetFunction().
2202: Collective on SNES
2204: Input Parameters:
2205: + snes - the SNES context
2206: - x - input vector
2208: Output Parameter:
2209: . y - function vector, as set by SNESSetFunction()
2211: Notes:
2212: SNESComputeFunction() is typically used within nonlinear solvers
2213: implementations, so most users would not generally call this routine
2214: themselves.
2216: Level: developer
2218: .keywords: SNES, nonlinear, compute, function
2220: .seealso: SNESSetFunction(), SNESGetFunction()
2221: @*/
2222: PetscErrorCode SNESComputeFunction(SNES snes,Vec x,Vec y)
2223: {
2225: DM dm;
2226: DMSNES sdm;
2234: VecValidValues(x,2,PETSC_TRUE);
2236: SNESGetDM(snes,&dm);
2237: DMGetDMSNES(dm,&sdm);
2238: if (sdm->ops->computefunction) {
2239: if (sdm->ops->computefunction != SNESObjectiveComputeFunctionDefaultFD) {
2240: PetscLogEventBegin(SNES_FunctionEval,snes,x,y,0);
2241: }
2242: VecLockPush(x);
2243: PetscStackPush("SNES user function");
2244: (*sdm->ops->computefunction)(snes,x,y,sdm->functionctx);
2245: PetscStackPop;
2246: VecLockPop(x);
2247: if (sdm->ops->computefunction != SNESObjectiveComputeFunctionDefaultFD) {
2248: PetscLogEventEnd(SNES_FunctionEval,snes,x,y,0);
2249: }
2250: } else if (snes->vec_rhs) {
2251: MatMult(snes->jacobian, x, y);
2252: } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Must call SNESSetFunction() or SNESSetDM() before SNESComputeFunction(), likely called from SNESSolve().");
2253: if (snes->vec_rhs) {
2254: VecAXPY(y,-1.0,snes->vec_rhs);
2255: }
2256: snes->nfuncs++;
2257: /*
2258: domainerror might not be set on all processes; so we tag vector locally with Inf and the next inner product or norm will
2259: propagate the value to all processes
2260: */
2261: if (snes->domainerror) {
2262: VecSetInf(y);
2263: }
2264: return(0);
2265: }
2267: /*@
2268: SNESComputeNGS - Calls the Gauss-Seidel function that has been set with SNESSetNGS().
2270: Collective on SNES
2272: Input Parameters:
2273: + snes - the SNES context
2274: . x - input vector
2275: - b - rhs vector
2277: Output Parameter:
2278: . x - new solution vector
2280: Notes:
2281: SNESComputeNGS() is typically used within composed nonlinear solver
2282: implementations, so most users would not generally call this routine
2283: themselves.
2285: Level: developer
2287: .keywords: SNES, nonlinear, compute, function
2289: .seealso: SNESSetNGS(), SNESComputeFunction()
2290: @*/
2291: PetscErrorCode SNESComputeNGS(SNES snes,Vec b,Vec x)
2292: {
2294: DM dm;
2295: DMSNES sdm;
2303: if (b) {VecValidValues(b,2,PETSC_TRUE);}
2304: PetscLogEventBegin(SNES_NGSEval,snes,x,b,0);
2305: SNESGetDM(snes,&dm);
2306: DMGetDMSNES(dm,&sdm);
2307: if (sdm->ops->computegs) {
2308: if (b) {VecLockPush(b);}
2309: PetscStackPush("SNES user NGS");
2310: (*sdm->ops->computegs)(snes,x,b,sdm->gsctx);
2311: PetscStackPop;
2312: if (b) {VecLockPop(b);}
2313: } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Must call SNESSetNGS() before SNESComputeNGS(), likely called from SNESSolve().");
2314: PetscLogEventEnd(SNES_NGSEval,snes,x,b,0);
2315: return(0);
2316: }
2318: PetscErrorCode SNESTestJacobian(SNES snes)
2319: {
2320: Mat A,B,C,D,jacobian;
2321: Vec x = snes->vec_sol,f = snes->vec_func;
2322: PetscErrorCode ierr;
2323: PetscReal nrm,gnorm;
2324: PetscReal threshold = 1.e-5;
2325: PetscInt m,n,M,N;
2326: void *functx;
2327: PetscBool complete_print = PETSC_FALSE,threshold_print = PETSC_FALSE,test = PETSC_FALSE,flg;
2328: PetscViewer viewer,mviewer;
2329: MPI_Comm comm;
2330: PetscInt tabs;
2331: static PetscBool directionsprinted = PETSC_FALSE;
2332: PetscViewerFormat format;
2335: PetscObjectOptionsBegin((PetscObject)snes);
2336: PetscOptionsName("-snes_test_jacobian","Compare hand-coded and finite difference Jacobians","None",&test);
2337: PetscOptionsReal("-snes_test_jacobian", "Threshold for element difference between hand-coded and finite difference being meaningful", "None", threshold, &threshold,NULL);
2338: PetscOptionsViewer("-snes_test_jacobian_view","View difference between hand-coded and finite difference Jacobians element entries","None",&mviewer,&format,&complete_print);
2339: if (!complete_print) {
2340: PetscOptionsViewer("-snes_test_jacobian_display","Display difference between hand-coded and finite difference Jacobians","None",&mviewer,&format,&complete_print);
2341: }
2342: /* for compatibility with PETSc 3.9 and older. */
2343: PetscOptionsReal("-snes_test_jacobian_display_threshold", "Display difference between hand-coded and finite difference Jacobians which exceed input threshold", "None", threshold, &threshold, &threshold_print);
2344: PetscOptionsEnd();
2345: if (!test) return(0);
2347: PetscObjectGetComm((PetscObject)snes,&comm);
2348: PetscViewerASCIIGetStdout(comm,&viewer);
2349: PetscViewerASCIIGetTab(viewer, &tabs);
2350: PetscViewerASCIISetTab(viewer, ((PetscObject)snes)->tablevel);
2351: PetscViewerASCIIPrintf(viewer," ---------- Testing Jacobian -------------\n");
2352: if (!complete_print && !directionsprinted) {
2353: PetscViewerASCIIPrintf(viewer," Run with -snes_test_jacobian_view and optionally -snes_test_jacobian <threshold> to show difference\n");
2354: PetscViewerASCIIPrintf(viewer," of hand-coded and finite difference Jacobian entries greater than <threshold>.\n");
2355: }
2356: if (!directionsprinted) {
2357: PetscViewerASCIIPrintf(viewer," Testing hand-coded Jacobian, if (for double precision runs) ||J - Jfd||_F/||J||_F is\n");
2358: PetscViewerASCIIPrintf(viewer," O(1.e-8), the hand-coded Jacobian is probably correct.\n");
2359: directionsprinted = PETSC_TRUE;
2360: }
2361: if (complete_print) {
2362: PetscViewerPushFormat(mviewer,format);
2363: }
2365: /* evaluate the function at this point because SNESComputeJacobianDefault() assumes that the function has been evaluated and put into snes->vec_func */
2366: SNESComputeFunction(snes,x,f);
2368: PetscObjectTypeCompare((PetscObject)snes->jacobian,MATMFFD,&flg);
2369: if (!flg) jacobian = snes->jacobian;
2370: else jacobian = snes->jacobian_pre;
2372: while (jacobian) {
2373: PetscObjectTypeCompareAny((PetscObject)jacobian,&flg,MATSEQAIJ,MATMPIAIJ,MATSEQDENSE,MATMPIDENSE,MATSEQBAIJ,MATMPIBAIJ,MATSEQSBAIJ,MATMPIBAIJ,"");
2374: if (flg) {
2375: A = jacobian;
2376: PetscObjectReference((PetscObject)A);
2377: } else {
2378: MatComputeExplicitOperator(jacobian,&A);
2379: }
2381: MatCreate(PetscObjectComm((PetscObject)A),&B);
2382: MatGetSize(A,&M,&N);
2383: MatGetLocalSize(A,&m,&n);
2384: MatSetSizes(B,m,n,M,N);
2385: MatSetType(B,((PetscObject)A)->type_name);
2386: MatSetUp(B);
2387: MatSetOption(B,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE);
2389: SNESGetFunction(snes,NULL,NULL,&functx);
2390: SNESComputeJacobianDefault(snes,x,B,B,functx);
2392: MatDuplicate(B,MAT_COPY_VALUES,&D);
2393: MatAYPX(D,-1.0,A,DIFFERENT_NONZERO_PATTERN);
2394: MatNorm(D,NORM_FROBENIUS,&nrm);
2395: MatNorm(A,NORM_FROBENIUS,&gnorm);
2396: MatDestroy(&D);
2397: if (!gnorm) gnorm = 1; /* just in case */
2398: PetscViewerASCIIPrintf(viewer," ||J - Jfd||_F/||J||_F = %g, ||J - Jfd||_F = %g\n",(double)(nrm/gnorm),(double)nrm);
2400: if (complete_print) {
2401: PetscViewerASCIIPrintf(viewer," Hand-coded Jacobian ----------\n");
2402: MatView(jacobian,mviewer);
2403: PetscViewerASCIIPrintf(viewer," Finite difference Jacobian ----------\n");
2404: MatView(B,mviewer);
2405: }
2407: if (threshold_print) {
2408: PetscInt Istart, Iend, *ccols, bncols, cncols, j, row;
2409: PetscScalar *cvals;
2410: const PetscInt *bcols;
2411: const PetscScalar *bvals;
2413: MatAYPX(B,-1.0,A,DIFFERENT_NONZERO_PATTERN);
2414: MatCreate(PetscObjectComm((PetscObject)A),&C);
2415: MatSetSizes(C,m,n,M,N);
2416: MatSetType(C,((PetscObject)A)->type_name);
2417: MatSetUp(C);
2418: MatSetOption(C,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE);
2419: MatGetOwnershipRange(B,&Istart,&Iend);
2421: for (row = Istart; row < Iend; row++) {
2422: MatGetRow(B,row,&bncols,&bcols,&bvals);
2423: PetscMalloc2(bncols,&ccols,bncols,&cvals);
2424: for (j = 0, cncols = 0; j < bncols; j++) {
2425: if (PetscAbsScalar(bvals[j]) > threshold) {
2426: ccols[cncols] = bcols[j];
2427: cvals[cncols] = bvals[j];
2428: cncols += 1;
2429: }
2430: }
2431: if (cncols) {
2432: MatSetValues(C,1,&row,cncols,ccols,cvals,INSERT_VALUES);
2433: }
2434: MatRestoreRow(B,row,&bncols,&bcols,&bvals);
2435: PetscFree2(ccols,cvals);
2436: }
2437: MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);
2438: MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);
2439: PetscViewerASCIIPrintf(viewer," Hand-coded minus finite-difference Jacobian with tolerance %g ----------\n",(double)threshold);
2440: MatView(C,complete_print ? mviewer : viewer);
2441: MatDestroy(&C);
2442: }
2443: MatDestroy(&A);
2444: MatDestroy(&B);
2446: if (jacobian != snes->jacobian_pre) {
2447: jacobian = snes->jacobian_pre;
2448: PetscViewerASCIIPrintf(viewer," ---------- Testing Jacobian for preconditioner -------------\n");
2449: }
2450: else jacobian = NULL;
2451: }
2452: if (complete_print) {
2453: PetscViewerPopFormat(mviewer);
2454: }
2455: PetscViewerASCIISetTab(viewer,tabs);
2456: return(0);
2457: }
2459: /*@
2460: SNESComputeJacobian - Computes the Jacobian matrix that has been set with SNESSetJacobian().
2462: Collective on SNES and Mat
2464: Input Parameters:
2465: + snes - the SNES context
2466: - x - input vector
2468: Output Parameters:
2469: + A - Jacobian matrix
2470: - B - optional preconditioning matrix
2472: Options Database Keys:
2473: + -snes_lag_preconditioner <lag>
2474: . -snes_lag_jacobian <lag>
2475: . -snes_test_jacobian - compare the user provided Jacobian with one compute via finite differences to check for errors
2476: . -snes_test_jacobian_display - display the user provided Jacobian, the finite difference Jacobian and the difference between them to help users detect the location of errors in the user provided Jacobian
2477: . -snes_test_jacobian_display_threshold <numerical value> - display entries in the difference between the user provided Jacobian and finite difference Jacobian that are greater than a certain value to help users detect errors
2478: . -snes_compare_explicit - Compare the computed Jacobian to the finite difference Jacobian and output the differences
2479: . -snes_compare_explicit_draw - Compare the computed Jacobian to the finite difference Jacobian and draw the result
2480: . -snes_compare_explicit_contour - Compare the computed Jacobian to the finite difference Jacobian and draw a contour plot with the result
2481: . -snes_compare_operator - Make the comparison options above use the operator instead of the preconditioning matrix
2482: . -snes_compare_coloring - Compute the finite difference Jacobian using coloring and display norms of difference
2483: . -snes_compare_coloring_display - Compute the finite differece Jacobian using coloring and display verbose differences
2484: . -snes_compare_coloring_threshold - Display only those matrix entries that differ by more than a given threshold
2485: . -snes_compare_coloring_threshold_atol - Absolute tolerance for difference in matrix entries to be displayed by -snes_compare_coloring_threshold
2486: . -snes_compare_coloring_threshold_rtol - Relative tolerance for difference in matrix entries to be displayed by -snes_compare_coloring_threshold
2487: . -snes_compare_coloring_draw - Compute the finite differece Jacobian using coloring and draw differences
2488: - -snes_compare_coloring_draw_contour - Compute the finite differece Jacobian using coloring and show contours of matrices and differences
2491: Notes:
2492: Most users should not need to explicitly call this routine, as it
2493: is used internally within the nonlinear solvers.
2495: Developer Notes:
2496: This has duplicative ways of checking the accuracy of the user provided Jacobian (see the options above). This is for historical reasons, the routine SNESTestJacobian() use to used
2497: for with the SNESType of test that has been removed.
2499: Level: developer
2501: .keywords: SNES, compute, Jacobian, matrix
2503: .seealso: SNESSetJacobian(), KSPSetOperators(), MatStructure, SNESSetLagPreconditioner(), SNESSetLagJacobian()
2504: @*/
2505: PetscErrorCode SNESComputeJacobian(SNES snes,Vec X,Mat A,Mat B)
2506: {
2508: PetscBool flag;
2509: DM dm;
2510: DMSNES sdm;
2511: KSP ksp;
2517: VecValidValues(X,2,PETSC_TRUE);
2518: SNESGetDM(snes,&dm);
2519: DMGetDMSNES(dm,&sdm);
2521: if (!sdm->ops->computejacobian) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_USER,"Must call SNESSetJacobian(), DMSNESSetJacobian(), DMDASNESSetJacobianLocal(), etc");
2523: /* make sure that MatAssemblyBegin/End() is called on A matrix if it is matrix free */
2525: if (snes->lagjacobian == -2) {
2526: snes->lagjacobian = -1;
2528: PetscInfo(snes,"Recomputing Jacobian/preconditioner because lag is -2 (means compute Jacobian, but then never again) \n");
2529: } else if (snes->lagjacobian == -1) {
2530: PetscInfo(snes,"Reusing Jacobian/preconditioner because lag is -1\n");
2531: PetscObjectTypeCompare((PetscObject)A,MATMFFD,&flag);
2532: if (flag) {
2533: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
2534: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
2535: }
2536: return(0);
2537: } else if (snes->lagjacobian > 1 && (snes->iter + snes->jac_iter) % snes->lagjacobian) {
2538: PetscInfo2(snes,"Reusing Jacobian/preconditioner because lag is %D and SNES iteration is %D\n",snes->lagjacobian,snes->iter);
2539: PetscObjectTypeCompare((PetscObject)A,MATMFFD,&flag);
2540: if (flag) {
2541: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
2542: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
2543: }
2544: return(0);
2545: }
2546: if (snes->npc && snes->npcside== PC_LEFT) {
2547: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
2548: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
2549: return(0);
2550: }
2552: PetscLogEventBegin(SNES_JacobianEval,snes,X,A,B);
2553: VecLockPush(X);
2554: PetscStackPush("SNES user Jacobian function");
2555: (*sdm->ops->computejacobian)(snes,X,A,B,sdm->jacobianctx);
2556: PetscStackPop;
2557: VecLockPop(X);
2558: PetscLogEventEnd(SNES_JacobianEval,snes,X,A,B);
2560: /* the next line ensures that snes->ksp exists */
2561: SNESGetKSP(snes,&ksp);
2562: if (snes->lagpreconditioner == -2) {
2563: PetscInfo(snes,"Rebuilding preconditioner exactly once since lag is -2\n");
2564: KSPSetReusePreconditioner(snes->ksp,PETSC_FALSE);
2565: snes->lagpreconditioner = -1;
2566: } else if (snes->lagpreconditioner == -1) {
2567: PetscInfo(snes,"Reusing preconditioner because lag is -1\n");
2568: KSPSetReusePreconditioner(snes->ksp,PETSC_TRUE);
2569: } else if (snes->lagpreconditioner > 1 && (snes->iter + snes->pre_iter) % snes->lagpreconditioner) {
2570: PetscInfo2(snes,"Reusing preconditioner because lag is %D and SNES iteration is %D\n",snes->lagpreconditioner,snes->iter);
2571: KSPSetReusePreconditioner(snes->ksp,PETSC_TRUE);
2572: } else {
2573: PetscInfo(snes,"Rebuilding preconditioner\n");
2574: KSPSetReusePreconditioner(snes->ksp,PETSC_FALSE);
2575: }
2577: SNESTestJacobian(snes);
2578: /* make sure user returned a correct Jacobian and preconditioner */
2581: {
2582: PetscBool flag = PETSC_FALSE,flag_draw = PETSC_FALSE,flag_contour = PETSC_FALSE,flag_operator = PETSC_FALSE;
2583: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_explicit",NULL,NULL,&flag);
2584: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_explicit_draw",NULL,NULL,&flag_draw);
2585: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_explicit_draw_contour",NULL,NULL,&flag_contour);
2586: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_operator",NULL,NULL,&flag_operator);
2587: if (flag || flag_draw || flag_contour) {
2588: Mat Bexp_mine = NULL,Bexp,FDexp;
2589: PetscViewer vdraw,vstdout;
2590: PetscBool flg;
2591: if (flag_operator) {
2592: MatComputeExplicitOperator(A,&Bexp_mine);
2593: Bexp = Bexp_mine;
2594: } else {
2595: /* See if the preconditioning matrix can be viewed and added directly */
2596: PetscObjectTypeCompareAny((PetscObject)B,&flg,MATSEQAIJ,MATMPIAIJ,MATSEQDENSE,MATMPIDENSE,MATSEQBAIJ,MATMPIBAIJ,MATSEQSBAIJ,MATMPIBAIJ,"");
2597: if (flg) Bexp = B;
2598: else {
2599: /* If the "preconditioning" matrix is itself MATSHELL or some other type without direct support */
2600: MatComputeExplicitOperator(B,&Bexp_mine);
2601: Bexp = Bexp_mine;
2602: }
2603: }
2604: MatConvert(Bexp,MATSAME,MAT_INITIAL_MATRIX,&FDexp);
2605: SNESComputeJacobianDefault(snes,X,FDexp,FDexp,NULL);
2606: PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)snes),&vstdout);
2607: if (flag_draw || flag_contour) {
2608: PetscViewerDrawOpen(PetscObjectComm((PetscObject)snes),0,"Explicit Jacobians",PETSC_DECIDE,PETSC_DECIDE,300,300,&vdraw);
2609: if (flag_contour) {PetscViewerPushFormat(vdraw,PETSC_VIEWER_DRAW_CONTOUR);}
2610: } else vdraw = NULL;
2611: PetscViewerASCIIPrintf(vstdout,"Explicit %s\n",flag_operator ? "Jacobian" : "preconditioning Jacobian");
2612: if (flag) {MatView(Bexp,vstdout);}
2613: if (vdraw) {MatView(Bexp,vdraw);}
2614: PetscViewerASCIIPrintf(vstdout,"Finite difference Jacobian\n");
2615: if (flag) {MatView(FDexp,vstdout);}
2616: if (vdraw) {MatView(FDexp,vdraw);}
2617: MatAYPX(FDexp,-1.0,Bexp,SAME_NONZERO_PATTERN);
2618: PetscViewerASCIIPrintf(vstdout,"User-provided matrix minus finite difference Jacobian\n");
2619: if (flag) {MatView(FDexp,vstdout);}
2620: if (vdraw) { /* Always use contour for the difference */
2621: PetscViewerPushFormat(vdraw,PETSC_VIEWER_DRAW_CONTOUR);
2622: MatView(FDexp,vdraw);
2623: PetscViewerPopFormat(vdraw);
2624: }
2625: if (flag_contour) {PetscViewerPopFormat(vdraw);}
2626: PetscViewerDestroy(&vdraw);
2627: MatDestroy(&Bexp_mine);
2628: MatDestroy(&FDexp);
2629: }
2630: }
2631: {
2632: PetscBool flag = PETSC_FALSE,flag_display = PETSC_FALSE,flag_draw = PETSC_FALSE,flag_contour = PETSC_FALSE,flag_threshold = PETSC_FALSE;
2633: PetscReal threshold_atol = PETSC_SQRT_MACHINE_EPSILON,threshold_rtol = 10*PETSC_SQRT_MACHINE_EPSILON;
2634: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_coloring",NULL,NULL,&flag);
2635: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_coloring_display",NULL,NULL,&flag_display);
2636: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_coloring_draw",NULL,NULL,&flag_draw);
2637: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_coloring_draw_contour",NULL,NULL,&flag_contour);
2638: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_coloring_threshold",NULL,NULL,&flag_threshold);
2639: if (flag_threshold) {
2640: PetscOptionsGetReal(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-snes_compare_coloring_threshold_rtol",&threshold_rtol,NULL);
2641: PetscOptionsGetReal(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-snes_compare_coloring_threshold_atol",&threshold_atol,NULL);
2642: }
2643: if (flag || flag_display || flag_draw || flag_contour || flag_threshold) {
2644: Mat Bfd;
2645: PetscViewer vdraw,vstdout;
2646: MatColoring coloring;
2647: ISColoring iscoloring;
2648: MatFDColoring matfdcoloring;
2649: PetscErrorCode (*func)(SNES,Vec,Vec,void*);
2650: void *funcctx;
2651: PetscReal norm1,norm2,normmax;
2653: MatDuplicate(B,MAT_DO_NOT_COPY_VALUES,&Bfd);
2654: MatColoringCreate(Bfd,&coloring);
2655: MatColoringSetType(coloring,MATCOLORINGSL);
2656: MatColoringSetFromOptions(coloring);
2657: MatColoringApply(coloring,&iscoloring);
2658: MatColoringDestroy(&coloring);
2659: MatFDColoringCreate(Bfd,iscoloring,&matfdcoloring);
2660: MatFDColoringSetFromOptions(matfdcoloring);
2661: MatFDColoringSetUp(Bfd,iscoloring,matfdcoloring);
2662: ISColoringDestroy(&iscoloring);
2664: /* This method of getting the function is currently unreliable since it doesn't work for DM local functions. */
2665: SNESGetFunction(snes,NULL,&func,&funcctx);
2666: MatFDColoringSetFunction(matfdcoloring,(PetscErrorCode (*)(void))func,funcctx);
2667: PetscObjectSetOptionsPrefix((PetscObject)matfdcoloring,((PetscObject)snes)->prefix);
2668: PetscObjectAppendOptionsPrefix((PetscObject)matfdcoloring,"coloring_");
2669: MatFDColoringSetFromOptions(matfdcoloring);
2670: MatFDColoringApply(Bfd,matfdcoloring,X,snes);
2671: MatFDColoringDestroy(&matfdcoloring);
2673: PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)snes),&vstdout);
2674: if (flag_draw || flag_contour) {
2675: PetscViewerDrawOpen(PetscObjectComm((PetscObject)snes),0,"Colored Jacobians",PETSC_DECIDE,PETSC_DECIDE,300,300,&vdraw);
2676: if (flag_contour) {PetscViewerPushFormat(vdraw,PETSC_VIEWER_DRAW_CONTOUR);}
2677: } else vdraw = NULL;
2678: PetscViewerASCIIPrintf(vstdout,"Explicit preconditioning Jacobian\n");
2679: if (flag_display) {MatView(B,vstdout);}
2680: if (vdraw) {MatView(B,vdraw);}
2681: PetscViewerASCIIPrintf(vstdout,"Colored Finite difference Jacobian\n");
2682: if (flag_display) {MatView(Bfd,vstdout);}
2683: if (vdraw) {MatView(Bfd,vdraw);}
2684: MatAYPX(Bfd,-1.0,B,SAME_NONZERO_PATTERN);
2685: MatNorm(Bfd,NORM_1,&norm1);
2686: MatNorm(Bfd,NORM_FROBENIUS,&norm2);
2687: MatNorm(Bfd,NORM_MAX,&normmax);
2688: PetscViewerASCIIPrintf(vstdout,"User-provided matrix minus finite difference Jacobian, norm1=%g normFrob=%g normmax=%g\n",(double)norm1,(double)norm2,(double)normmax);
2689: if (flag_display) {MatView(Bfd,vstdout);}
2690: if (vdraw) { /* Always use contour for the difference */
2691: PetscViewerPushFormat(vdraw,PETSC_VIEWER_DRAW_CONTOUR);
2692: MatView(Bfd,vdraw);
2693: PetscViewerPopFormat(vdraw);
2694: }
2695: if (flag_contour) {PetscViewerPopFormat(vdraw);}
2697: if (flag_threshold) {
2698: PetscInt bs,rstart,rend,i;
2699: MatGetBlockSize(B,&bs);
2700: MatGetOwnershipRange(B,&rstart,&rend);
2701: for (i=rstart; i<rend; i++) {
2702: const PetscScalar *ba,*ca;
2703: const PetscInt *bj,*cj;
2704: PetscInt bn,cn,j,maxentrycol = -1,maxdiffcol = -1,maxrdiffcol = -1;
2705: PetscReal maxentry = 0,maxdiff = 0,maxrdiff = 0;
2706: MatGetRow(B,i,&bn,&bj,&ba);
2707: MatGetRow(Bfd,i,&cn,&cj,&ca);
2708: if (bn != cn) SETERRQ(((PetscObject)A)->comm,PETSC_ERR_PLIB,"Unexpected different nonzero pattern in -snes_compare_coloring_threshold");
2709: for (j=0; j<bn; j++) {
2710: PetscReal rdiff = PetscAbsScalar(ca[j]) / (threshold_atol + threshold_rtol*PetscAbsScalar(ba[j]));
2711: if (PetscAbsScalar(ba[j]) > PetscAbs(maxentry)) {
2712: maxentrycol = bj[j];
2713: maxentry = PetscRealPart(ba[j]);
2714: }
2715: if (PetscAbsScalar(ca[j]) > PetscAbs(maxdiff)) {
2716: maxdiffcol = bj[j];
2717: maxdiff = PetscRealPart(ca[j]);
2718: }
2719: if (rdiff > maxrdiff) {
2720: maxrdiffcol = bj[j];
2721: maxrdiff = rdiff;
2722: }
2723: }
2724: if (maxrdiff > 1) {
2725: PetscViewerASCIIPrintf(vstdout,"row %D (maxentry=%g at %D, maxdiff=%g at %D, maxrdiff=%g at %D):",i,(double)maxentry,maxentrycol,(double)maxdiff,maxdiffcol,(double)maxrdiff,maxrdiffcol);
2726: for (j=0; j<bn; j++) {
2727: PetscReal rdiff;
2728: rdiff = PetscAbsScalar(ca[j]) / (threshold_atol + threshold_rtol*PetscAbsScalar(ba[j]));
2729: if (rdiff > 1) {
2730: PetscViewerASCIIPrintf(vstdout," (%D,%g:%g)",bj[j],(double)PetscRealPart(ba[j]),(double)PetscRealPart(ca[j]));
2731: }
2732: }
2733: PetscViewerASCIIPrintf(vstdout,"\n",i,maxentry,maxdiff,maxrdiff);
2734: }
2735: MatRestoreRow(B,i,&bn,&bj,&ba);
2736: MatRestoreRow(Bfd,i,&cn,&cj,&ca);
2737: }
2738: }
2739: PetscViewerDestroy(&vdraw);
2740: MatDestroy(&Bfd);
2741: }
2742: }
2743: return(0);
2744: }
2746: /*MC
2747: SNESJacobianFunction - Function used to convey the nonlinear Jacobian of the function to be solved by SNES
2749: Synopsis:
2750: #include "petscsnes.h"
2751: PetscErrorCode SNESJacobianFunction(SNES snes,Vec x,Mat Amat,Mat Pmat,void *ctx);
2753: + x - input vector
2754: . Amat - the matrix that defines the (approximate) Jacobian
2755: . Pmat - the matrix to be used in constructing the preconditioner, usually the same as Amat.
2756: - ctx - [optional] user-defined Jacobian context
2758: Level: intermediate
2760: .seealso: SNESSetFunction(), SNESGetFunction(), SNESSetJacobian(), SNESGetJacobian()
2761: M*/
2763: /*@C
2764: SNESSetJacobian - Sets the function to compute Jacobian as well as the
2765: location to store the matrix.
2767: Logically Collective on SNES and Mat
2769: Input Parameters:
2770: + snes - the SNES context
2771: . Amat - the matrix that defines the (approximate) Jacobian
2772: . Pmat - the matrix to be used in constructing the preconditioner, usually the same as Amat.
2773: . J - Jacobian evaluation routine (if NULL then SNES retains any previously set value), see SNESJacobianFunction for details
2774: - ctx - [optional] user-defined context for private data for the
2775: Jacobian evaluation routine (may be NULL) (if NULL then SNES retains any previously set value)
2777: Notes:
2778: If the Amat matrix and Pmat matrix are different you must call MatAssemblyBegin/End() on
2779: each matrix.
2781: If you know the operator Amat has a null space you can use MatSetNullSpace() and MatSetTransposeNullSpace() to supply the null
2782: space to Amat and the KSP solvers will automatically use that null space as needed during the solution process.
2784: If using SNESComputeJacobianDefaultColor() to assemble a Jacobian, the ctx argument
2785: must be a MatFDColoring.
2787: Other defect-correction schemes can be used by computing a different matrix in place of the Jacobian. One common
2788: example is to use the "Picard linearization" which only differentiates through the highest order parts of each term.
2790: Level: beginner
2792: .keywords: SNES, nonlinear, set, Jacobian, matrix
2794: .seealso: KSPSetOperators(), SNESSetFunction(), MatMFFDComputeJacobian(), SNESComputeJacobianDefaultColor(), MatStructure, J,
2795: SNESSetPicard(), SNESJacobianFunction
2796: @*/
2797: PetscErrorCode SNESSetJacobian(SNES snes,Mat Amat,Mat Pmat,PetscErrorCode (*J)(SNES,Vec,Mat,Mat,void*),void *ctx)
2798: {
2800: DM dm;
2808: SNESGetDM(snes,&dm);
2809: DMSNESSetJacobian(dm,J,ctx);
2810: if (Amat) {
2811: PetscObjectReference((PetscObject)Amat);
2812: MatDestroy(&snes->jacobian);
2814: snes->jacobian = Amat;
2815: }
2816: if (Pmat) {
2817: PetscObjectReference((PetscObject)Pmat);
2818: MatDestroy(&snes->jacobian_pre);
2820: snes->jacobian_pre = Pmat;
2821: }
2822: return(0);
2823: }
2825: /*@C
2826: SNESGetJacobian - Returns the Jacobian matrix and optionally the user
2827: provided context for evaluating the Jacobian.
2829: Not Collective, but Mat object will be parallel if SNES object is
2831: Input Parameter:
2832: . snes - the nonlinear solver context
2834: Output Parameters:
2835: + Amat - location to stash (approximate) Jacobian matrix (or NULL)
2836: . Pmat - location to stash matrix used to compute the preconditioner (or NULL)
2837: . J - location to put Jacobian function (or NULL), see SNESJacobianFunction for details on its calling sequence
2838: - ctx - location to stash Jacobian ctx (or NULL)
2840: Level: advanced
2842: .seealso: SNESSetJacobian(), SNESComputeJacobian(), SNESJacobianFunction, SNESGetFunction()
2843: @*/
2844: PetscErrorCode SNESGetJacobian(SNES snes,Mat *Amat,Mat *Pmat,PetscErrorCode (**J)(SNES,Vec,Mat,Mat,void*),void **ctx)
2845: {
2847: DM dm;
2848: DMSNES sdm;
2852: if (Amat) *Amat = snes->jacobian;
2853: if (Pmat) *Pmat = snes->jacobian_pre;
2854: SNESGetDM(snes,&dm);
2855: DMGetDMSNES(dm,&sdm);
2856: if (J) *J = sdm->ops->computejacobian;
2857: if (ctx) *ctx = sdm->jacobianctx;
2858: return(0);
2859: }
2861: /*@
2862: SNESSetUp - Sets up the internal data structures for the later use
2863: of a nonlinear solver.
2865: Collective on SNES
2867: Input Parameters:
2868: . snes - the SNES context
2870: Notes:
2871: For basic use of the SNES solvers the user need not explicitly call
2872: SNESSetUp(), since these actions will automatically occur during
2873: the call to SNESSolve(). However, if one wishes to control this
2874: phase separately, SNESSetUp() should be called after SNESCreate()
2875: and optional routines of the form SNESSetXXX(), but before SNESSolve().
2877: Level: advanced
2879: .keywords: SNES, nonlinear, setup
2881: .seealso: SNESCreate(), SNESSolve(), SNESDestroy()
2882: @*/
2883: PetscErrorCode SNESSetUp(SNES snes)
2884: {
2886: DM dm;
2887: DMSNES sdm;
2888: SNESLineSearch linesearch, pclinesearch;
2889: void *lsprectx,*lspostctx;
2890: PetscErrorCode (*precheck)(SNESLineSearch,Vec,Vec,PetscBool*,void*);
2891: PetscErrorCode (*postcheck)(SNESLineSearch,Vec,Vec,Vec,PetscBool*,PetscBool*,void*);
2892: PetscErrorCode (*func)(SNES,Vec,Vec,void*);
2893: Vec f,fpc;
2894: void *funcctx;
2895: PetscErrorCode (*jac)(SNES,Vec,Mat,Mat,void*);
2896: void *jacctx,*appctx;
2897: Mat j,jpre;
2901: if (snes->setupcalled) return(0);
2903: if (!((PetscObject)snes)->type_name) {
2904: SNESSetType(snes,SNESNEWTONLS);
2905: }
2907: SNESGetFunction(snes,&snes->vec_func,NULL,NULL);
2909: SNESGetDM(snes,&dm);
2910: DMGetDMSNES(dm,&sdm);
2911: if (!sdm->ops->computefunction) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_ARG_WRONGSTATE,"Function never provided to SNES object");
2912: if (!sdm->ops->computejacobian) {
2913: DMSNESSetJacobian(dm,SNESComputeJacobianDefaultColor,NULL);
2914: }
2915: if (!snes->vec_func) {
2916: DMCreateGlobalVector(dm,&snes->vec_func);
2917: }
2919: if (!snes->ksp) {
2920: SNESGetKSP(snes, &snes->ksp);
2921: }
2923: if (!snes->linesearch) {
2924: SNESGetLineSearch(snes, &snes->linesearch);
2925: }
2926: SNESLineSearchSetFunction(snes->linesearch,SNESComputeFunction);
2928: if (snes->npc && (snes->npcside== PC_LEFT)) {
2929: snes->mf = PETSC_TRUE;
2930: snes->mf_operator = PETSC_FALSE;
2931: }
2933: if (snes->npc) {
2934: /* copy the DM over */
2935: SNESGetDM(snes,&dm);
2936: SNESSetDM(snes->npc,dm);
2938: SNESGetFunction(snes,&f,&func,&funcctx);
2939: VecDuplicate(f,&fpc);
2940: SNESSetFunction(snes->npc,fpc,func,funcctx);
2941: SNESGetJacobian(snes,&j,&jpre,&jac,&jacctx);
2942: SNESSetJacobian(snes->npc,j,jpre,jac,jacctx);
2943: SNESGetApplicationContext(snes,&appctx);
2944: SNESSetApplicationContext(snes->npc,appctx);
2945: VecDestroy(&fpc);
2947: /* copy the function pointers over */
2948: PetscObjectCopyFortranFunctionPointers((PetscObject)snes,(PetscObject)snes->npc);
2950: /* default to 1 iteration */
2951: SNESSetTolerances(snes->npc,0.0,0.0,0.0,1,snes->npc->max_funcs);
2952: if (snes->npcside==PC_RIGHT) {
2953: SNESSetNormSchedule(snes->npc,SNES_NORM_FINAL_ONLY);
2954: } else {
2955: SNESSetNormSchedule(snes->npc,SNES_NORM_NONE);
2956: }
2957: SNESSetFromOptions(snes->npc);
2959: /* copy the line search context over */
2960: SNESGetLineSearch(snes,&linesearch);
2961: SNESGetLineSearch(snes->npc,&pclinesearch);
2962: SNESLineSearchGetPreCheck(linesearch,&precheck,&lsprectx);
2963: SNESLineSearchGetPostCheck(linesearch,&postcheck,&lspostctx);
2964: SNESLineSearchSetPreCheck(pclinesearch,precheck,lsprectx);
2965: SNESLineSearchSetPostCheck(pclinesearch,postcheck,lspostctx);
2966: PetscObjectCopyFortranFunctionPointers((PetscObject)linesearch, (PetscObject)pclinesearch);
2967: }
2968: if (snes->mf) {
2969: SNESSetUpMatrixFree_Private(snes, snes->mf_operator, snes->mf_version);
2970: }
2971: if (snes->ops->usercompute && !snes->user) {
2972: (*snes->ops->usercompute)(snes,(void**)&snes->user);
2973: }
2975: snes->jac_iter = 0;
2976: snes->pre_iter = 0;
2978: if (snes->ops->setup) {
2979: (*snes->ops->setup)(snes);
2980: }
2982: if (snes->npc && (snes->npcside== PC_LEFT)) {
2983: if (snes->functype == SNES_FUNCTION_PRECONDITIONED) {
2984: SNESGetLineSearch(snes,&linesearch);
2985: SNESLineSearchSetFunction(linesearch,SNESComputeFunctionDefaultNPC);
2986: }
2987: }
2989: snes->setupcalled = PETSC_TRUE;
2990: return(0);
2991: }
2993: /*@
2994: SNESReset - Resets a SNES context to the snessetupcalled = 0 state and removes any allocated Vecs and Mats
2996: Collective on SNES
2998: Input Parameter:
2999: . snes - iterative context obtained from SNESCreate()
3001: Level: intermediate
3003: Notes:
3004: Also calls the application context destroy routine set with SNESSetComputeApplicationContext()
3006: .keywords: SNES, destroy
3008: .seealso: SNESCreate(), SNESSetUp(), SNESSolve()
3009: @*/
3010: PetscErrorCode SNESReset(SNES snes)
3011: {
3016: if (snes->ops->userdestroy && snes->user) {
3017: (*snes->ops->userdestroy)((void**)&snes->user);
3018: snes->user = NULL;
3019: }
3020: if (snes->npc) {
3021: SNESReset(snes->npc);
3022: }
3024: if (snes->ops->reset) {
3025: (*snes->ops->reset)(snes);
3026: }
3027: if (snes->ksp) {
3028: KSPReset(snes->ksp);
3029: }
3031: if (snes->linesearch) {
3032: SNESLineSearchReset(snes->linesearch);
3033: }
3035: VecDestroy(&snes->vec_rhs);
3036: VecDestroy(&snes->vec_sol);
3037: VecDestroy(&snes->vec_sol_update);
3038: VecDestroy(&snes->vec_func);
3039: MatDestroy(&snes->jacobian);
3040: MatDestroy(&snes->jacobian_pre);
3041: VecDestroyVecs(snes->nwork,&snes->work);
3042: VecDestroyVecs(snes->nvwork,&snes->vwork);
3044: snes->alwayscomputesfinalresidual = PETSC_FALSE;
3046: snes->nwork = snes->nvwork = 0;
3047: snes->setupcalled = PETSC_FALSE;
3048: return(0);
3049: }
3051: /*@
3052: SNESDestroy - Destroys the nonlinear solver context that was created
3053: with SNESCreate().
3055: Collective on SNES
3057: Input Parameter:
3058: . snes - the SNES context
3060: Level: beginner
3062: .keywords: SNES, nonlinear, destroy
3064: .seealso: SNESCreate(), SNESSolve()
3065: @*/
3066: PetscErrorCode SNESDestroy(SNES *snes)
3067: {
3071: if (!*snes) return(0);
3073: if (--((PetscObject)(*snes))->refct > 0) {*snes = 0; return(0);}
3075: SNESReset((*snes));
3076: SNESDestroy(&(*snes)->npc);
3078: /* if memory was published with SAWs then destroy it */
3079: PetscObjectSAWsViewOff((PetscObject)*snes);
3080: if ((*snes)->ops->destroy) {(*((*snes))->ops->destroy)((*snes));}
3082: if ((*snes)->dm) {DMCoarsenHookRemove((*snes)->dm,DMCoarsenHook_SNESVecSol,DMRestrictHook_SNESVecSol,*snes);}
3083: DMDestroy(&(*snes)->dm);
3084: KSPDestroy(&(*snes)->ksp);
3085: SNESLineSearchDestroy(&(*snes)->linesearch);
3087: PetscFree((*snes)->kspconvctx);
3088: if ((*snes)->ops->convergeddestroy) {
3089: (*(*snes)->ops->convergeddestroy)((*snes)->cnvP);
3090: }
3091: if ((*snes)->conv_malloc) {
3092: PetscFree((*snes)->conv_hist);
3093: PetscFree((*snes)->conv_hist_its);
3094: }
3095: SNESMonitorCancel((*snes));
3096: PetscHeaderDestroy(snes);
3097: return(0);
3098: }
3100: /* ----------- Routines to set solver parameters ---------- */
3102: /*@
3103: SNESSetLagPreconditioner - Determines when the preconditioner is rebuilt in the nonlinear solve.
3105: Logically Collective on SNES
3107: Input Parameters:
3108: + snes - the SNES context
3109: - lag - -1 indicates NEVER rebuild, 1 means rebuild every time the Jacobian is computed within a single nonlinear solve, 2 means every second time
3110: the Jacobian is built etc. -2 indicates rebuild preconditioner at next chance but then never rebuild after that
3112: Options Database Keys:
3113: . -snes_lag_preconditioner <lag>
3115: Notes:
3116: The default is 1
3117: The preconditioner is ALWAYS built in the first iteration of a nonlinear solve unless lag is -1
3118: If -1 is used before the very first nonlinear solve the preconditioner is still built because there is no previous preconditioner to use
3120: Level: intermediate
3122: .keywords: SNES, nonlinear, set, convergence, tolerances
3124: .seealso: SNESSetTrustRegionTolerance(), SNESGetLagPreconditioner(), SNESSetLagJacobian(), SNESGetLagJacobian()
3126: @*/
3127: PetscErrorCode SNESSetLagPreconditioner(SNES snes,PetscInt lag)
3128: {
3131: if (lag < -2) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Lag must be -2, -1, 1 or greater");
3132: if (!lag) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Lag cannot be 0");
3134: snes->lagpreconditioner = lag;
3135: return(0);
3136: }
3138: /*@
3139: SNESSetGridSequence - sets the number of steps of grid sequencing that SNES does
3141: Logically Collective on SNES
3143: Input Parameters:
3144: + snes - the SNES context
3145: - steps - the number of refinements to do, defaults to 0
3147: Options Database Keys:
3148: . -snes_grid_sequence <steps>
3150: Level: intermediate
3152: Notes:
3153: Use SNESGetSolution() to extract the fine grid solution after grid sequencing.
3155: .keywords: SNES, nonlinear, set, convergence, tolerances
3157: .seealso: SNESSetTrustRegionTolerance(), SNESGetLagPreconditioner(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESGetGridSequence()
3159: @*/
3160: PetscErrorCode SNESSetGridSequence(SNES snes,PetscInt steps)
3161: {
3165: snes->gridsequence = steps;
3166: return(0);
3167: }
3169: /*@
3170: SNESGetGridSequence - gets the number of steps of grid sequencing that SNES does
3172: Logically Collective on SNES
3174: Input Parameter:
3175: . snes - the SNES context
3177: Output Parameter:
3178: . steps - the number of refinements to do, defaults to 0
3180: Options Database Keys:
3181: . -snes_grid_sequence <steps>
3183: Level: intermediate
3185: Notes:
3186: Use SNESGetSolution() to extract the fine grid solution after grid sequencing.
3188: .keywords: SNES, nonlinear, set, convergence, tolerances
3190: .seealso: SNESSetTrustRegionTolerance(), SNESGetLagPreconditioner(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESSetGridSequence()
3192: @*/
3193: PetscErrorCode SNESGetGridSequence(SNES snes,PetscInt *steps)
3194: {
3197: *steps = snes->gridsequence;
3198: return(0);
3199: }
3201: /*@
3202: SNESGetLagPreconditioner - Indicates how often the preconditioner is rebuilt
3204: Not Collective
3206: Input Parameter:
3207: . snes - the SNES context
3209: Output Parameter:
3210: . lag - -1 indicates NEVER rebuild, 1 means rebuild every time the Jacobian is computed within a single nonlinear solve, 2 means every second time
3211: the Jacobian is built etc. -2 indicates rebuild preconditioner at next chance but then never rebuild after that
3213: Options Database Keys:
3214: . -snes_lag_preconditioner <lag>
3216: Notes:
3217: The default is 1
3218: The preconditioner is ALWAYS built in the first iteration of a nonlinear solve unless lag is -1
3220: Level: intermediate
3222: .keywords: SNES, nonlinear, set, convergence, tolerances
3224: .seealso: SNESSetTrustRegionTolerance(), SNESSetLagPreconditioner()
3226: @*/
3227: PetscErrorCode SNESGetLagPreconditioner(SNES snes,PetscInt *lag)
3228: {
3231: *lag = snes->lagpreconditioner;
3232: return(0);
3233: }
3235: /*@
3236: SNESSetLagJacobian - Determines when the Jacobian is rebuilt in the nonlinear solve. See SNESSetLagPreconditioner() for determining how
3237: often the preconditioner is rebuilt.
3239: Logically Collective on SNES
3241: Input Parameters:
3242: + snes - the SNES context
3243: - lag - -1 indicates NEVER rebuild, 1 means rebuild every time the Jacobian is computed within a single nonlinear solve, 2 means every second time
3244: the Jacobian is built etc. -2 means rebuild at next chance but then never again
3246: Options Database Keys:
3247: . -snes_lag_jacobian <lag>
3249: Notes:
3250: The default is 1
3251: The Jacobian is ALWAYS built in the first iteration of a nonlinear solve unless lag is -1
3252: If -1 is used before the very first nonlinear solve the CODE WILL FAIL! because no Jacobian is used, use -2 to indicate you want it recomputed
3253: at the next Newton step but never again (unless it is reset to another value)
3255: Level: intermediate
3257: .keywords: SNES, nonlinear, set, convergence, tolerances
3259: .seealso: SNESSetTrustRegionTolerance(), SNESGetLagPreconditioner(), SNESSetLagPreconditioner(), SNESGetLagJacobian()
3261: @*/
3262: PetscErrorCode SNESSetLagJacobian(SNES snes,PetscInt lag)
3263: {
3266: if (lag < -2) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Lag must be -2, -1, 1 or greater");
3267: if (!lag) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Lag cannot be 0");
3269: snes->lagjacobian = lag;
3270: return(0);
3271: }
3273: /*@
3274: SNESGetLagJacobian - Indicates how often the Jacobian is rebuilt. See SNESGetLagPreconditioner() to determine when the preconditioner is rebuilt
3276: Not Collective
3278: Input Parameter:
3279: . snes - the SNES context
3281: Output Parameter:
3282: . lag - -1 indicates NEVER rebuild, 1 means rebuild every time the Jacobian is computed within a single nonlinear solve, 2 means every second time
3283: the Jacobian is built etc.
3285: Options Database Keys:
3286: . -snes_lag_jacobian <lag>
3288: Notes:
3289: The default is 1
3290: The jacobian is ALWAYS built in the first iteration of a nonlinear solve unless lag is -1
3292: Level: intermediate
3294: .keywords: SNES, nonlinear, set, convergence, tolerances
3296: .seealso: SNESSetTrustRegionTolerance(), SNESSetLagJacobian(), SNESSetLagPreconditioner(), SNESGetLagPreconditioner()
3298: @*/
3299: PetscErrorCode SNESGetLagJacobian(SNES snes,PetscInt *lag)
3300: {
3303: *lag = snes->lagjacobian;
3304: return(0);
3305: }
3307: /*@
3308: SNESSetLagJacobianPersists - Set whether or not the Jacobian lagging persists through multiple solves
3310: Logically collective on SNES
3312: Input Parameter:
3313: + snes - the SNES context
3314: - flg - jacobian lagging persists if true
3316: Options Database Keys:
3317: . -snes_lag_jacobian_persists <flg>
3319: Notes:
3320: This is useful both for nonlinear preconditioning, where it's appropriate to have the Jacobian be stale by
3321: several solves, and for implicit time-stepping, where Jacobian lagging in the inner nonlinear solve over several
3322: timesteps may present huge efficiency gains.
3324: Level: developer
3326: .keywords: SNES, nonlinear, lag
3328: .seealso: SNESSetLagPreconditionerPersists(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESGetNPC()
3330: @*/
3331: PetscErrorCode SNESSetLagJacobianPersists(SNES snes,PetscBool flg)
3332: {
3336: snes->lagjac_persist = flg;
3337: return(0);
3338: }
3340: /*@
3341: SNESSetLagPreconditionerPersists - Set whether or not the preconditioner lagging persists through multiple solves
3343: Logically Collective on SNES
3345: Input Parameter:
3346: + snes - the SNES context
3347: - flg - preconditioner lagging persists if true
3349: Options Database Keys:
3350: . -snes_lag_jacobian_persists <flg>
3352: Notes:
3353: This is useful both for nonlinear preconditioning, where it's appropriate to have the preconditioner be stale
3354: by several solves, and for implicit time-stepping, where preconditioner lagging in the inner nonlinear solve over
3355: several timesteps may present huge efficiency gains.
3357: Level: developer
3359: .keywords: SNES, nonlinear, lag
3361: .seealso: SNESSetLagJacobianPersists(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESGetNPC()
3363: @*/
3364: PetscErrorCode SNESSetLagPreconditionerPersists(SNES snes,PetscBool flg)
3365: {
3369: snes->lagpre_persist = flg;
3370: return(0);
3371: }
3373: /*@
3374: SNESSetForceIteration - force SNESSolve() to take at least one iteration regardless of the initial residual norm
3376: Logically Collective on SNES
3378: Input Parameters:
3379: + snes - the SNES context
3380: - force - PETSC_TRUE require at least one iteration
3382: Options Database Keys:
3383: . -snes_force_iteration <force> - Sets forcing an iteration
3385: Notes:
3386: This is used sometimes with TS to prevent TS from detecting a false steady state solution
3388: Level: intermediate
3390: .keywords: SNES, nonlinear, set, convergence, tolerances
3392: .seealso: SNESSetTrustRegionTolerance(), SNESSetDivergenceTolerance()
3393: @*/
3394: PetscErrorCode SNESSetForceIteration(SNES snes,PetscBool force)
3395: {
3398: snes->forceiteration = force;
3399: return(0);
3400: }
3402: /*@
3403: SNESGetForceIteration - Whether or not to force SNESSolve() take at least one iteration regardless of the initial residual norm
3405: Logically Collective on SNES
3407: Input Parameters:
3408: . snes - the SNES context
3410: Output Parameter:
3411: . force - PETSC_TRUE requires at least one iteration.
3413: .keywords: SNES, nonlinear, set, convergence, tolerances
3415: Level: intermediate
3417: .seealso: SNESSetForceIteration(), SNESSetTrustRegionTolerance(), SNESSetDivergenceTolerance()
3418: @*/
3419: PetscErrorCode SNESGetForceIteration(SNES snes,PetscBool *force)
3420: {
3423: *force = snes->forceiteration;
3424: return(0);
3425: }
3427: /*@
3428: SNESSetTolerances - Sets various parameters used in convergence tests.
3430: Logically Collective on SNES
3432: Input Parameters:
3433: + snes - the SNES context
3434: . abstol - absolute convergence tolerance
3435: . rtol - relative convergence tolerance
3436: . stol - convergence tolerance in terms of the norm of the change in the solution between steps, || delta x || < stol*|| x ||
3437: . maxit - maximum number of iterations
3438: - maxf - maximum number of function evaluations (-1 indicates no limit)
3440: Options Database Keys:
3441: + -snes_atol <abstol> - Sets abstol
3442: . -snes_rtol <rtol> - Sets rtol
3443: . -snes_stol <stol> - Sets stol
3444: . -snes_max_it <maxit> - Sets maxit
3445: - -snes_max_funcs <maxf> - Sets maxf
3447: Notes:
3448: The default maximum number of iterations is 50.
3449: The default maximum number of function evaluations is 1000.
3451: Level: intermediate
3453: .keywords: SNES, nonlinear, set, convergence, tolerances
3455: .seealso: SNESSetTrustRegionTolerance(), SNESSetDivergenceTolerance(), SNESSetForceIteration()
3456: @*/
3457: PetscErrorCode SNESSetTolerances(SNES snes,PetscReal abstol,PetscReal rtol,PetscReal stol,PetscInt maxit,PetscInt maxf)
3458: {
3467: if (abstol != PETSC_DEFAULT) {
3468: if (abstol < 0.0) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Absolute tolerance %g must be non-negative",(double)abstol);
3469: snes->abstol = abstol;
3470: }
3471: if (rtol != PETSC_DEFAULT) {
3472: if (rtol < 0.0 || 1.0 <= rtol) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Relative tolerance %g must be non-negative and less than 1.0",(double)rtol);
3473: snes->rtol = rtol;
3474: }
3475: if (stol != PETSC_DEFAULT) {
3476: if (stol < 0.0) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Step tolerance %g must be non-negative",(double)stol);
3477: snes->stol = stol;
3478: }
3479: if (maxit != PETSC_DEFAULT) {
3480: if (maxit < 0) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Maximum number of iterations %D must be non-negative",maxit);
3481: snes->max_its = maxit;
3482: }
3483: if (maxf != PETSC_DEFAULT) {
3484: if (maxf < -1) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Maximum number of function evaluations %D must be -1 or nonnegative",maxf);
3485: snes->max_funcs = maxf;
3486: }
3487: snes->tolerancesset = PETSC_TRUE;
3488: return(0);
3489: }
3491: /*@
3492: SNESSetDivergenceTolerance - Sets the divergence tolerance used for the SNES divergence test.
3494: Logically Collective on SNES
3496: Input Parameters:
3497: + snes - the SNES context
3498: - divtol - the divergence tolerance. Use -1 to deactivate the test.
3500: Options Database Keys:
3501: + -snes_divergence_tolerance <divtol> - Sets divtol
3503: Notes:
3504: The default divergence tolerance is 1e4.
3506: Level: intermediate
3508: .keywords: SNES, nonlinear, set, divergence, tolerance
3510: .seealso: SNESSetTolerances(), SNESGetDivergenceTolerance
3511: @*/
3512: PetscErrorCode SNESSetDivergenceTolerance(SNES snes,PetscReal divtol)
3513: {
3518: if (divtol != PETSC_DEFAULT) {
3519: snes->divtol = divtol;
3520: }
3521: else {
3522: snes->divtol = 1.0e4;
3523: }
3524: return(0);
3525: }
3527: /*@
3528: SNESGetTolerances - Gets various parameters used in convergence tests.
3530: Not Collective
3532: Input Parameters:
3533: + snes - the SNES context
3534: . atol - absolute convergence tolerance
3535: . rtol - relative convergence tolerance
3536: . stol - convergence tolerance in terms of the norm
3537: of the change in the solution between steps
3538: . maxit - maximum number of iterations
3539: - maxf - maximum number of function evaluations
3541: Notes:
3542: The user can specify NULL for any parameter that is not needed.
3544: Level: intermediate
3546: .keywords: SNES, nonlinear, get, convergence, tolerances
3548: .seealso: SNESSetTolerances()
3549: @*/
3550: PetscErrorCode SNESGetTolerances(SNES snes,PetscReal *atol,PetscReal *rtol,PetscReal *stol,PetscInt *maxit,PetscInt *maxf)
3551: {
3554: if (atol) *atol = snes->abstol;
3555: if (rtol) *rtol = snes->rtol;
3556: if (stol) *stol = snes->stol;
3557: if (maxit) *maxit = snes->max_its;
3558: if (maxf) *maxf = snes->max_funcs;
3559: return(0);
3560: }
3562: /*@
3563: SNESGetDivergenceTolerance - Gets divergence tolerance used in divergence test.
3565: Not Collective
3567: Input Parameters:
3568: + snes - the SNES context
3569: - divtol - divergence tolerance
3571: Level: intermediate
3573: .keywords: SNES, nonlinear, get, divergence, tolerance
3575: .seealso: SNESSetDivergenceTolerance()
3576: @*/
3577: PetscErrorCode SNESGetDivergenceTolerance(SNES snes,PetscReal *divtol)
3578: {
3581: if (divtol) *divtol = snes->divtol;
3582: return(0);
3583: }
3585: /*@
3586: SNESSetTrustRegionTolerance - Sets the trust region parameter tolerance.
3588: Logically Collective on SNES
3590: Input Parameters:
3591: + snes - the SNES context
3592: - tol - tolerance
3594: Options Database Key:
3595: . -snes_trtol <tol> - Sets tol
3597: Level: intermediate
3599: .keywords: SNES, nonlinear, set, trust region, tolerance
3601: .seealso: SNESSetTolerances()
3602: @*/
3603: PetscErrorCode SNESSetTrustRegionTolerance(SNES snes,PetscReal tol)
3604: {
3608: snes->deltatol = tol;
3609: return(0);
3610: }
3612: /*
3613: Duplicate the lg monitors for SNES from KSP; for some reason with
3614: dynamic libraries things don't work under Sun4 if we just use
3615: macros instead of functions
3616: */
3617: PetscErrorCode SNESMonitorLGResidualNorm(SNES snes,PetscInt it,PetscReal norm,void *ctx)
3618: {
3623: KSPMonitorLGResidualNorm((KSP)snes,it,norm,ctx);
3624: return(0);
3625: }
3627: PetscErrorCode SNESMonitorLGCreate(MPI_Comm comm,const char host[],const char label[],int x,int y,int m,int n,PetscDrawLG *lgctx)
3628: {
3632: KSPMonitorLGResidualNormCreate(comm,host,label,x,y,m,n,lgctx);
3633: return(0);
3634: }
3636: PETSC_INTERN PetscErrorCode SNESMonitorRange_Private(SNES,PetscInt,PetscReal*);
3638: PetscErrorCode SNESMonitorLGRange(SNES snes,PetscInt n,PetscReal rnorm,void *monctx)
3639: {
3640: PetscDrawLG lg;
3641: PetscErrorCode ierr;
3642: PetscReal x,y,per;
3643: PetscViewer v = (PetscViewer)monctx;
3644: static PetscReal prev; /* should be in the context */
3645: PetscDraw draw;
3649: PetscViewerDrawGetDrawLG(v,0,&lg);
3650: if (!n) {PetscDrawLGReset(lg);}
3651: PetscDrawLGGetDraw(lg,&draw);
3652: PetscDrawSetTitle(draw,"Residual norm");
3653: x = (PetscReal)n;
3654: if (rnorm > 0.0) y = PetscLog10Real(rnorm);
3655: else y = -15.0;
3656: PetscDrawLGAddPoint(lg,&x,&y);
3657: if (n < 20 || !(n % 5) || snes->reason) {
3658: PetscDrawLGDraw(lg);
3659: PetscDrawLGSave(lg);
3660: }
3662: PetscViewerDrawGetDrawLG(v,1,&lg);
3663: if (!n) {PetscDrawLGReset(lg);}
3664: PetscDrawLGGetDraw(lg,&draw);
3665: PetscDrawSetTitle(draw,"% elemts > .2*max elemt");
3666: SNESMonitorRange_Private(snes,n,&per);
3667: x = (PetscReal)n;
3668: y = 100.0*per;
3669: PetscDrawLGAddPoint(lg,&x,&y);
3670: if (n < 20 || !(n % 5) || snes->reason) {
3671: PetscDrawLGDraw(lg);
3672: PetscDrawLGSave(lg);
3673: }
3675: PetscViewerDrawGetDrawLG(v,2,&lg);
3676: if (!n) {prev = rnorm;PetscDrawLGReset(lg);}
3677: PetscDrawLGGetDraw(lg,&draw);
3678: PetscDrawSetTitle(draw,"(norm -oldnorm)/oldnorm");
3679: x = (PetscReal)n;
3680: y = (prev - rnorm)/prev;
3681: PetscDrawLGAddPoint(lg,&x,&y);
3682: if (n < 20 || !(n % 5) || snes->reason) {
3683: PetscDrawLGDraw(lg);
3684: PetscDrawLGSave(lg);
3685: }
3687: PetscViewerDrawGetDrawLG(v,3,&lg);
3688: if (!n) {PetscDrawLGReset(lg);}
3689: PetscDrawLGGetDraw(lg,&draw);
3690: PetscDrawSetTitle(draw,"(norm -oldnorm)/oldnorm*(% > .2 max)");
3691: x = (PetscReal)n;
3692: y = (prev - rnorm)/(prev*per);
3693: if (n > 2) { /*skip initial crazy value */
3694: PetscDrawLGAddPoint(lg,&x,&y);
3695: }
3696: if (n < 20 || !(n % 5) || snes->reason) {
3697: PetscDrawLGDraw(lg);
3698: PetscDrawLGSave(lg);
3699: }
3700: prev = rnorm;
3701: return(0);
3702: }
3704: /*@
3705: SNESMonitor - runs the user provided monitor routines, if they exist
3707: Collective on SNES
3709: Input Parameters:
3710: + snes - nonlinear solver context obtained from SNESCreate()
3711: . iter - iteration number
3712: - rnorm - relative norm of the residual
3714: Notes:
3715: This routine is called by the SNES implementations.
3716: It does not typically need to be called by the user.
3718: Level: developer
3720: .seealso: SNESMonitorSet()
3721: @*/
3722: PetscErrorCode SNESMonitor(SNES snes,PetscInt iter,PetscReal rnorm)
3723: {
3725: PetscInt i,n = snes->numbermonitors;
3728: VecLockPush(snes->vec_sol);
3729: for (i=0; i<n; i++) {
3730: (*snes->monitor[i])(snes,iter,rnorm,snes->monitorcontext[i]);
3731: }
3732: VecLockPop(snes->vec_sol);
3733: return(0);
3734: }
3736: /* ------------ Routines to set performance monitoring options ----------- */
3738: /*MC
3739: SNESMonitorFunction - functional form passed to SNESMonitorSet() to monitor convergence of nonlinear solver
3741: Synopsis:
3742: #include <petscsnes.h>
3743: $ PetscErrorCode SNESMonitorFunction(SNES snes,PetscInt its, PetscReal norm,void *mctx)
3745: + snes - the SNES context
3746: . its - iteration number
3747: . norm - 2-norm function value (may be estimated)
3748: - mctx - [optional] monitoring context
3750: Level: advanced
3752: .seealso: SNESMonitorSet(), SNESMonitorGet()
3753: M*/
3755: /*@C
3756: SNESMonitorSet - Sets an ADDITIONAL function that is to be used at every
3757: iteration of the nonlinear solver to display the iteration's
3758: progress.
3760: Logically Collective on SNES
3762: Input Parameters:
3763: + snes - the SNES context
3764: . f - the monitor function, see SNESMonitorFunction for the calling sequence
3765: . mctx - [optional] user-defined context for private data for the
3766: monitor routine (use NULL if no context is desired)
3767: - monitordestroy - [optional] routine that frees monitor context
3768: (may be NULL)
3770: Options Database Keys:
3771: + -snes_monitor - sets SNESMonitorDefault()
3772: . -snes_monitor_lg_residualnorm - sets line graph monitor,
3773: uses SNESMonitorLGCreate()
3774: - -snes_monitor_cancel - cancels all monitors that have
3775: been hardwired into a code by
3776: calls to SNESMonitorSet(), but
3777: does not cancel those set via
3778: the options database.
3780: Notes:
3781: Several different monitoring routines may be set by calling
3782: SNESMonitorSet() multiple times; all will be called in the
3783: order in which they were set.
3785: Fortran Notes:
3786: Only a single monitor function can be set for each SNES object
3788: Level: intermediate
3790: .keywords: SNES, nonlinear, set, monitor
3792: .seealso: SNESMonitorDefault(), SNESMonitorCancel(), SNESMonitorFunction
3793: @*/
3794: PetscErrorCode SNESMonitorSet(SNES snes,PetscErrorCode (*f)(SNES,PetscInt,PetscReal,void*),void *mctx,PetscErrorCode (*monitordestroy)(void**))
3795: {
3796: PetscInt i;
3798: PetscBool identical;
3802: for (i=0; i<snes->numbermonitors;i++) {
3803: PetscMonitorCompare((PetscErrorCode (*)(void))f,mctx,monitordestroy,(PetscErrorCode (*)(void))snes->monitor[i],snes->monitorcontext[i],snes->monitordestroy[i],&identical);
3804: if (identical) return(0);
3805: }
3806: if (snes->numbermonitors >= MAXSNESMONITORS) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Too many monitors set");
3807: snes->monitor[snes->numbermonitors] = f;
3808: snes->monitordestroy[snes->numbermonitors] = monitordestroy;
3809: snes->monitorcontext[snes->numbermonitors++] = (void*)mctx;
3810: return(0);
3811: }
3813: /*@
3814: SNESMonitorCancel - Clears all the monitor functions for a SNES object.
3816: Logically Collective on SNES
3818: Input Parameters:
3819: . snes - the SNES context
3821: Options Database Key:
3822: . -snes_monitor_cancel - cancels all monitors that have been hardwired
3823: into a code by calls to SNESMonitorSet(), but does not cancel those
3824: set via the options database
3826: Notes:
3827: There is no way to clear one specific monitor from a SNES object.
3829: Level: intermediate
3831: .keywords: SNES, nonlinear, set, monitor
3833: .seealso: SNESMonitorDefault(), SNESMonitorSet()
3834: @*/
3835: PetscErrorCode SNESMonitorCancel(SNES snes)
3836: {
3838: PetscInt i;
3842: for (i=0; i<snes->numbermonitors; i++) {
3843: if (snes->monitordestroy[i]) {
3844: (*snes->monitordestroy[i])(&snes->monitorcontext[i]);
3845: }
3846: }
3847: snes->numbermonitors = 0;
3848: return(0);
3849: }
3851: /*MC
3852: SNESConvergenceTestFunction - functional form used for testing of convergence of nonlinear solver
3854: Synopsis:
3855: #include <petscsnes.h>
3856: $ PetscErrorCode SNESConvergenceTest(SNES snes,PetscInt it,PetscReal xnorm,PetscReal gnorm,PetscReal f,SNESConvergedReason *reason,void *cctx)
3858: + snes - the SNES context
3859: . it - current iteration (0 is the first and is before any Newton step)
3860: . cctx - [optional] convergence context
3861: . reason - reason for convergence/divergence
3862: . xnorm - 2-norm of current iterate
3863: . gnorm - 2-norm of current step
3864: - f - 2-norm of function
3866: Level: intermediate
3868: .seealso: SNESSetConvergenceTest(), SNESGetConvergenceTest()
3869: M*/
3871: /*@C
3872: SNESSetConvergenceTest - Sets the function that is to be used
3873: to test for convergence of the nonlinear iterative solution.
3875: Logically Collective on SNES
3877: Input Parameters:
3878: + snes - the SNES context
3879: . SNESConvergenceTestFunction - routine to test for convergence
3880: . cctx - [optional] context for private data for the convergence routine (may be NULL)
3881: - destroy - [optional] destructor for the context (may be NULL; NULL_FUNCTION in Fortran)
3883: Level: advanced
3885: .keywords: SNES, nonlinear, set, convergence, test
3887: .seealso: SNESConvergedDefault(), SNESConvergedSkip(), SNESConvergenceTestFunction
3888: @*/
3889: PetscErrorCode SNESSetConvergenceTest(SNES snes,PetscErrorCode (*SNESConvergenceTestFunction)(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*),void *cctx,PetscErrorCode (*destroy)(void*))
3890: {
3895: if (!SNESConvergenceTestFunction) SNESConvergenceTestFunction = SNESConvergedSkip;
3896: if (snes->ops->convergeddestroy) {
3897: (*snes->ops->convergeddestroy)(snes->cnvP);
3898: }
3899: snes->ops->converged = SNESConvergenceTestFunction;
3900: snes->ops->convergeddestroy = destroy;
3901: snes->cnvP = cctx;
3902: return(0);
3903: }
3905: /*@
3906: SNESGetConvergedReason - Gets the reason the SNES iteration was stopped.
3908: Not Collective
3910: Input Parameter:
3911: . snes - the SNES context
3913: Output Parameter:
3914: . reason - negative value indicates diverged, positive value converged, see SNESConvergedReason or the
3915: manual pages for the individual convergence tests for complete lists
3917: Options Database:
3918: . -snes_converged_reason - prints the reason to standard out
3920: Level: intermediate
3922: Notes:
3923: Should only be called after the call the SNESSolve() is complete, if it is called earlier it returns the value SNES__CONVERGED_ITERATING.
3925: .keywords: SNES, nonlinear, set, convergence, test
3927: .seealso: SNESSetConvergenceTest(), SNESSetConvergedReason(), SNESConvergedReason
3928: @*/
3929: PetscErrorCode SNESGetConvergedReason(SNES snes,SNESConvergedReason *reason)
3930: {
3934: *reason = snes->reason;
3935: return(0);
3936: }
3938: /*@
3939: SNESSetConvergedReason - Sets the reason the SNES iteration was stopped.
3941: Not Collective
3943: Input Parameters:
3944: + snes - the SNES context
3945: - reason - negative value indicates diverged, positive value converged, see SNESConvergedReason or the
3946: manual pages for the individual convergence tests for complete lists
3948: Level: intermediate
3950: .keywords: SNES, nonlinear, set, convergence, test
3951: .seealso: SNESGetConvergedReason(), SNESSetConvergenceTest(), SNESConvergedReason
3952: @*/
3953: PetscErrorCode SNESSetConvergedReason(SNES snes,SNESConvergedReason reason)
3954: {
3957: snes->reason = reason;
3958: return(0);
3959: }
3961: /*@
3962: SNESSetConvergenceHistory - Sets the array used to hold the convergence history.
3964: Logically Collective on SNES
3966: Input Parameters:
3967: + snes - iterative context obtained from SNESCreate()
3968: . a - array to hold history, this array will contain the function norms computed at each step
3969: . its - integer array holds the number of linear iterations for each solve.
3970: . na - size of a and its
3971: - reset - PETSC_TRUE indicates each new nonlinear solve resets the history counter to zero,
3972: else it continues storing new values for new nonlinear solves after the old ones
3974: Notes:
3975: If 'a' and 'its' are NULL then space is allocated for the history. If 'na' PETSC_DECIDE or PETSC_DEFAULT then a
3976: default array of length 10000 is allocated.
3978: This routine is useful, e.g., when running a code for purposes
3979: of accurate performance monitoring, when no I/O should be done
3980: during the section of code that is being timed.
3982: Level: intermediate
3984: .keywords: SNES, set, convergence, history
3986: .seealso: SNESGetConvergenceHistory()
3988: @*/
3989: PetscErrorCode SNESSetConvergenceHistory(SNES snes,PetscReal a[],PetscInt its[],PetscInt na,PetscBool reset)
3990: {
3997: if (!a) {
3998: if (na == PETSC_DECIDE || na == PETSC_DEFAULT) na = 1000;
3999: PetscCalloc1(na,&a);
4000: PetscCalloc1(na,&its);
4002: snes->conv_malloc = PETSC_TRUE;
4003: }
4004: snes->conv_hist = a;
4005: snes->conv_hist_its = its;
4006: snes->conv_hist_max = na;
4007: snes->conv_hist_len = 0;
4008: snes->conv_hist_reset = reset;
4009: return(0);
4010: }
4012: #if defined(PETSC_HAVE_MATLAB_ENGINE)
4013: #include <engine.h> /* MATLAB include file */
4014: #include <mex.h> /* MATLAB include file */
4016: PETSC_EXTERN mxArray *SNESGetConvergenceHistoryMatlab(SNES snes)
4017: {
4018: mxArray *mat;
4019: PetscInt i;
4020: PetscReal *ar;
4023: mat = mxCreateDoubleMatrix(snes->conv_hist_len,1,mxREAL);
4024: ar = (PetscReal*) mxGetData(mat);
4025: for (i=0; i<snes->conv_hist_len; i++) ar[i] = snes->conv_hist[i];
4026: PetscFunctionReturn(mat);
4027: }
4028: #endif
4030: /*@C
4031: SNESGetConvergenceHistory - Gets the array used to hold the convergence history.
4033: Not Collective
4035: Input Parameter:
4036: . snes - iterative context obtained from SNESCreate()
4038: Output Parameters:
4039: . a - array to hold history
4040: . its - integer array holds the number of linear iterations (or
4041: negative if not converged) for each solve.
4042: - na - size of a and its
4044: Notes:
4045: The calling sequence for this routine in Fortran is
4046: $ call SNESGetConvergenceHistory(SNES snes, integer na, integer ierr)
4048: This routine is useful, e.g., when running a code for purposes
4049: of accurate performance monitoring, when no I/O should be done
4050: during the section of code that is being timed.
4052: Level: intermediate
4054: .keywords: SNES, get, convergence, history
4056: .seealso: SNESSetConvergencHistory()
4058: @*/
4059: PetscErrorCode SNESGetConvergenceHistory(SNES snes,PetscReal *a[],PetscInt *its[],PetscInt *na)
4060: {
4063: if (a) *a = snes->conv_hist;
4064: if (its) *its = snes->conv_hist_its;
4065: if (na) *na = snes->conv_hist_len;
4066: return(0);
4067: }
4069: /*@C
4070: SNESSetUpdate - Sets the general-purpose update function called
4071: at the beginning of every iteration of the nonlinear solve. Specifically
4072: it is called just before the Jacobian is "evaluated".
4074: Logically Collective on SNES
4076: Input Parameters:
4077: . snes - The nonlinear solver context
4078: . func - The function
4080: Calling sequence of func:
4081: . func (SNES snes, PetscInt step);
4083: . step - The current step of the iteration
4085: Level: advanced
4087: Note: This is NOT what one uses to update the ghost points before a function evaluation, that should be done at the beginning of your FormFunction()
4088: This is not used by most users.
4090: .keywords: SNES, update
4092: .seealso SNESSetJacobian(), SNESSolve()
4093: @*/
4094: PetscErrorCode SNESSetUpdate(SNES snes, PetscErrorCode (*func)(SNES, PetscInt))
4095: {
4098: snes->ops->update = func;
4099: return(0);
4100: }
4102: /*
4103: SNESScaleStep_Private - Scales a step so that its length is less than the
4104: positive parameter delta.
4106: Input Parameters:
4107: + snes - the SNES context
4108: . y - approximate solution of linear system
4109: . fnorm - 2-norm of current function
4110: - delta - trust region size
4112: Output Parameters:
4113: + gpnorm - predicted function norm at the new point, assuming local
4114: linearization. The value is zero if the step lies within the trust
4115: region, and exceeds zero otherwise.
4116: - ynorm - 2-norm of the step
4118: Note:
4119: For non-trust region methods such as SNESNEWTONLS, the parameter delta
4120: is set to be the maximum allowable step size.
4122: .keywords: SNES, nonlinear, scale, step
4123: */
4124: PetscErrorCode SNESScaleStep_Private(SNES snes,Vec y,PetscReal *fnorm,PetscReal *delta,PetscReal *gpnorm,PetscReal *ynorm)
4125: {
4126: PetscReal nrm;
4127: PetscScalar cnorm;
4135: VecNorm(y,NORM_2,&nrm);
4136: if (nrm > *delta) {
4137: nrm = *delta/nrm;
4138: *gpnorm = (1.0 - nrm)*(*fnorm);
4139: cnorm = nrm;
4140: VecScale(y,cnorm);
4141: *ynorm = *delta;
4142: } else {
4143: *gpnorm = 0.0;
4144: *ynorm = nrm;
4145: }
4146: return(0);
4147: }
4149: /*@
4150: SNESReasonView - Displays the reason a SNES solve converged or diverged to a viewer
4152: Collective on SNES
4154: Parameter:
4155: + snes - iterative context obtained from SNESCreate()
4156: - viewer - the viewer to display the reason
4159: Options Database Keys:
4160: . -snes_converged_reason - print reason for converged or diverged, also prints number of iterations
4162: Level: beginner
4164: .keywords: SNES, solve, linear system
4166: .seealso: SNESCreate(), SNESSetUp(), SNESDestroy(), SNESSetTolerances(), SNESConvergedDefault()
4168: @*/
4169: PetscErrorCode SNESReasonView(SNES snes,PetscViewer viewer)
4170: {
4171: PetscViewerFormat format;
4172: PetscBool isAscii;
4173: PetscErrorCode ierr;
4176: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&isAscii);
4177: if (isAscii) {
4178: PetscViewerGetFormat(viewer, &format);
4179: PetscViewerASCIIAddTab(viewer,((PetscObject)snes)->tablevel);
4180: if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
4181: DM dm;
4182: Vec u;
4183: PetscDS prob;
4184: PetscInt Nf, f;
4185: PetscErrorCode (**exactFuncs)(PetscInt, PetscReal, const PetscReal[], PetscInt, PetscScalar[], void *);
4186: PetscReal error;
4188: SNESGetDM(snes, &dm);
4189: SNESGetSolution(snes, &u);
4190: DMGetDS(dm, &prob);
4191: PetscDSGetNumFields(prob, &Nf);
4192: PetscMalloc1(Nf, &exactFuncs);
4193: for (f = 0; f < Nf; ++f) {PetscDSGetExactSolution(prob, f, &exactFuncs[f]);}
4194: DMComputeL2Diff(dm, 0.0, exactFuncs, NULL, u, &error);
4195: PetscFree(exactFuncs);
4196: if (error < 1.0e-11) {PetscViewerASCIIPrintf(viewer, "L_2 Error: < 1.0e-11\n");}
4197: else {PetscViewerASCIIPrintf(viewer, "L_2 Error: %g\n", error);}
4198: }
4199: if (snes->reason > 0) {
4200: if (((PetscObject) snes)->prefix) {
4201: PetscViewerASCIIPrintf(viewer,"Nonlinear %s solve converged due to %s iterations %D\n",((PetscObject) snes)->prefix,SNESConvergedReasons[snes->reason],snes->iter);
4202: } else {
4203: PetscViewerASCIIPrintf(viewer,"Nonlinear solve converged due to %s iterations %D\n",SNESConvergedReasons[snes->reason],snes->iter);
4204: }
4205: } else {
4206: if (((PetscObject) snes)->prefix) {
4207: PetscViewerASCIIPrintf(viewer,"Nonlinear %s solve did not converge due to %s iterations %D\n",((PetscObject) snes)->prefix,SNESConvergedReasons[snes->reason],snes->iter);
4208: } else {
4209: PetscViewerASCIIPrintf(viewer,"Nonlinear solve did not converge due to %s iterations %D\n",SNESConvergedReasons[snes->reason],snes->iter);
4210: }
4211: }
4212: PetscViewerASCIISubtractTab(viewer,((PetscObject)snes)->tablevel);
4213: }
4214: return(0);
4215: }
4217: /*@C
4218: SNESReasonViewFromOptions - Processes command line options to determine if/how a SNESReason is to be viewed.
4220: Collective on SNES
4222: Input Parameters:
4223: . snes - the SNES object
4225: Level: intermediate
4227: @*/
4228: PetscErrorCode SNESReasonViewFromOptions(SNES snes)
4229: {
4230: PetscErrorCode ierr;
4231: PetscViewer viewer;
4232: PetscBool flg;
4233: static PetscBool incall = PETSC_FALSE;
4234: PetscViewerFormat format;
4237: if (incall) return(0);
4238: incall = PETSC_TRUE;
4239: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_converged_reason",&viewer,&format,&flg);
4240: if (flg) {
4241: PetscViewerPushFormat(viewer,format);
4242: SNESReasonView(snes,viewer);
4243: PetscViewerPopFormat(viewer);
4244: PetscViewerDestroy(&viewer);
4245: }
4246: incall = PETSC_FALSE;
4247: return(0);
4248: }
4250: /*@
4251: SNESSolve - Solves a nonlinear system F(x) = b.
4252: Call SNESSolve() after calling SNESCreate() and optional routines of the form SNESSetXXX().
4254: Collective on SNES
4256: Input Parameters:
4257: + snes - the SNES context
4258: . b - the constant part of the equation F(x) = b, or NULL to use zero.
4259: - x - the solution vector.
4261: Notes:
4262: The user should initialize the vector,x, with the initial guess
4263: for the nonlinear solve prior to calling SNESSolve. In particular,
4264: to employ an initial guess of zero, the user should explicitly set
4265: this vector to zero by calling VecSet().
4267: Level: beginner
4269: .keywords: SNES, nonlinear, solve
4271: .seealso: SNESCreate(), SNESDestroy(), SNESSetFunction(), SNESSetJacobian(), SNESSetGridSequence(), SNESGetSolution()
4272: @*/
4273: PetscErrorCode SNESSolve(SNES snes,Vec b,Vec x)
4274: {
4275: PetscErrorCode ierr;
4276: PetscBool flg;
4277: PetscInt grid;
4278: Vec xcreated = NULL;
4279: DM dm;
4288: /* High level operations using the nonlinear solver */
4289: {
4290: PetscViewer viewer;
4291: PetscViewerFormat format;
4292: PetscInt num;
4293: PetscBool flg;
4294: static PetscBool incall = PETSC_FALSE;
4296: if (!incall) {
4297: /* Estimate the convergence rate of the discretization */
4298: PetscOptionsGetViewer(PetscObjectComm((PetscObject) snes), ((PetscObject) snes)->prefix, "-snes_convergence_estimate", &viewer, &format, &flg);
4299: if (flg) {
4300: PetscConvEst conv;
4301: DM dm;
4302: PetscReal *alpha; /* Convergence rate of the solution error for each field in the L_2 norm */
4303: PetscInt Nf;
4305: incall = PETSC_TRUE;
4306: SNESGetDM(snes, &dm);
4307: DMGetNumFields(dm, &Nf);
4308: PetscMalloc1(Nf, &alpha);
4309: PetscConvEstCreate(PetscObjectComm((PetscObject) snes), &conv);
4310: PetscConvEstSetSolver(conv, snes);
4311: PetscConvEstSetFromOptions(conv);
4312: PetscConvEstSetUp(conv);
4313: PetscConvEstGetConvRate(conv, alpha);
4314: PetscViewerPushFormat(viewer, format);
4315: PetscConvEstRateView(conv, alpha, viewer);
4316: PetscViewerPopFormat(viewer);
4317: PetscViewerDestroy(&viewer);
4318: PetscConvEstDestroy(&conv);
4319: PetscFree(alpha);
4320: incall = PETSC_FALSE;
4321: }
4322: /* Adaptively refine the initial grid */
4323: num = 1;
4324: PetscOptionsGetInt(NULL, ((PetscObject) snes)->prefix, "-snes_adapt_initial", &num, &flg);
4325: if (flg) {
4326: DMAdaptor adaptor;
4328: incall = PETSC_TRUE;
4329: DMAdaptorCreate(PETSC_COMM_WORLD, &adaptor);
4330: DMAdaptorSetSolver(adaptor, snes);
4331: DMAdaptorSetSequenceLength(adaptor, num);
4332: DMAdaptorSetFromOptions(adaptor);
4333: DMAdaptorSetUp(adaptor);
4334: DMAdaptorAdapt(adaptor, x, DM_ADAPTATION_INITIAL, &dm, &x);
4335: DMAdaptorDestroy(&adaptor);
4336: incall = PETSC_FALSE;
4337: }
4338: /* Use grid sequencing to adapt */
4339: num = 0;
4340: PetscOptionsGetInt(NULL, ((PetscObject) snes)->prefix, "-snes_adapt_sequence", &num, NULL);
4341: if (num) {
4342: DMAdaptor adaptor;
4344: incall = PETSC_TRUE;
4345: DMAdaptorCreate(PETSC_COMM_WORLD, &adaptor);
4346: DMAdaptorSetSolver(adaptor, snes);
4347: DMAdaptorSetSequenceLength(adaptor, num);
4348: DMAdaptorSetFromOptions(adaptor);
4349: DMAdaptorSetUp(adaptor);
4350: DMAdaptorAdapt(adaptor, x, DM_ADAPTATION_SEQUENTIAL, &dm, &x);
4351: DMAdaptorDestroy(&adaptor);
4352: incall = PETSC_FALSE;
4353: }
4354: }
4355: }
4356: if (!x) {
4357: SNESGetDM(snes,&dm);
4358: DMCreateGlobalVector(dm,&xcreated);
4359: x = xcreated;
4360: }
4361: SNESViewFromOptions(snes,NULL,"-snes_view_pre");
4363: for (grid=0; grid<snes->gridsequence; grid++) {PetscViewerASCIIPushTab(PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)snes)));}
4364: for (grid=0; grid<snes->gridsequence+1; grid++) {
4366: /* set solution vector */
4367: if (!grid) {PetscObjectReference((PetscObject)x);}
4368: VecDestroy(&snes->vec_sol);
4369: snes->vec_sol = x;
4370: SNESGetDM(snes,&dm);
4372: /* set affine vector if provided */
4373: if (b) { PetscObjectReference((PetscObject)b); }
4374: VecDestroy(&snes->vec_rhs);
4375: snes->vec_rhs = b;
4377: if (snes->vec_func == snes->vec_sol) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_IDN,"Solution vector cannot be function vector");
4378: if (snes->vec_rhs == snes->vec_sol) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_IDN,"Solution vector cannot be right hand side vector");
4379: if (!snes->vec_sol_update /* && snes->vec_sol */) {
4380: VecDuplicate(snes->vec_sol,&snes->vec_sol_update);
4381: PetscLogObjectParent((PetscObject)snes,(PetscObject)snes->vec_sol_update);
4382: }
4383: DMShellSetGlobalVector(dm,snes->vec_sol);
4384: SNESSetUp(snes);
4386: if (!grid) {
4387: if (snes->ops->computeinitialguess) {
4388: (*snes->ops->computeinitialguess)(snes,snes->vec_sol,snes->initialguessP);
4389: }
4390: }
4392: if (snes->conv_hist_reset) snes->conv_hist_len = 0;
4393: if (snes->counters_reset) {snes->nfuncs = 0; snes->linear_its = 0; snes->numFailures = 0;}
4395: PetscLogEventBegin(SNES_Solve,snes,0,0,0);
4396: (*snes->ops->solve)(snes);
4397: PetscLogEventEnd(SNES_Solve,snes,0,0,0);
4398: if (!snes->reason) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Internal error, solver returned without setting converged reason");
4399: snes->domainerror = PETSC_FALSE; /* clear the flag if it has been set */
4401: if (snes->lagjac_persist) snes->jac_iter += snes->iter;
4402: if (snes->lagpre_persist) snes->pre_iter += snes->iter;
4404: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_test_local_min",NULL,NULL,&flg);
4405: if (flg && !PetscPreLoadingOn) { SNESTestLocalMin(snes); }
4406: SNESReasonViewFromOptions(snes);
4408: if (snes->errorifnotconverged && snes->reason < 0) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_NOT_CONVERGED,"SNESSolve has not converged");
4409: if (snes->reason < 0) break;
4410: if (grid < snes->gridsequence) {
4411: DM fine;
4412: Vec xnew;
4413: Mat interp;
4415: DMRefine(snes->dm,PetscObjectComm((PetscObject)snes),&fine);
4416: if (!fine) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_INCOMP,"DMRefine() did not perform any refinement, cannot continue grid sequencing");
4417: DMCreateInterpolation(snes->dm,fine,&interp,NULL);
4418: DMCreateGlobalVector(fine,&xnew);
4419: MatInterpolate(interp,x,xnew);
4420: DMInterpolate(snes->dm,interp,fine);
4421: MatDestroy(&interp);
4422: x = xnew;
4424: SNESReset(snes);
4425: SNESSetDM(snes,fine);
4426: SNESResetFromOptions(snes);
4427: DMDestroy(&fine);
4428: PetscViewerASCIIPopTab(PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)snes)));
4429: }
4430: }
4431: SNESViewFromOptions(snes,NULL,"-snes_view");
4432: VecViewFromOptions(snes->vec_sol,(PetscObject)snes,"-snes_view_solution");
4434: VecDestroy(&xcreated);
4435: PetscObjectSAWsBlock((PetscObject)snes);
4436: return(0);
4437: }
4439: /* --------- Internal routines for SNES Package --------- */
4441: /*@C
4442: SNESSetType - Sets the method for the nonlinear solver.
4444: Collective on SNES
4446: Input Parameters:
4447: + snes - the SNES context
4448: - type - a known method
4450: Options Database Key:
4451: . -snes_type <type> - Sets the method; use -help for a list
4452: of available methods (for instance, newtonls or newtontr)
4454: Notes:
4455: See "petsc/include/petscsnes.h" for available methods (for instance)
4456: + SNESNEWTONLS - Newton's method with line search
4457: (systems of nonlinear equations)
4458: . SNESNEWTONTR - Newton's method with trust region
4459: (systems of nonlinear equations)
4461: Normally, it is best to use the SNESSetFromOptions() command and then
4462: set the SNES solver type from the options database rather than by using
4463: this routine. Using the options database provides the user with
4464: maximum flexibility in evaluating the many nonlinear solvers.
4465: The SNESSetType() routine is provided for those situations where it
4466: is necessary to set the nonlinear solver independently of the command
4467: line or options database. This might be the case, for example, when
4468: the choice of solver changes during the execution of the program,
4469: and the user's application is taking responsibility for choosing the
4470: appropriate method.
4472: Developer Notes:
4473: SNESRegister() adds a constructor for a new SNESType to SNESList, SNESSetType() locates
4474: the constructor in that list and calls it to create the spexific object.
4476: Level: intermediate
4478: .keywords: SNES, set, type
4480: .seealso: SNESType, SNESCreate(), SNESDestroy(), SNESGetType(), SNESSetFromOptions()
4482: @*/
4483: PetscErrorCode SNESSetType(SNES snes,SNESType type)
4484: {
4485: PetscErrorCode ierr,(*r)(SNES);
4486: PetscBool match;
4492: PetscObjectTypeCompare((PetscObject)snes,type,&match);
4493: if (match) return(0);
4495: PetscFunctionListFind(SNESList,type,&r);
4496: if (!r) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_UNKNOWN_TYPE,"Unable to find requested SNES type %s",type);
4497: /* Destroy the previous private SNES context */
4498: if (snes->ops->destroy) {
4499: (*(snes)->ops->destroy)(snes);
4500: snes->ops->destroy = NULL;
4501: }
4502: /* Reinitialize function pointers in SNESOps structure */
4503: snes->ops->setup = 0;
4504: snes->ops->solve = 0;
4505: snes->ops->view = 0;
4506: snes->ops->setfromoptions = 0;
4507: snes->ops->destroy = 0;
4508: /* Call the SNESCreate_XXX routine for this particular Nonlinear solver */
4509: snes->setupcalled = PETSC_FALSE;
4511: PetscObjectChangeTypeName((PetscObject)snes,type);
4512: (*r)(snes);
4513: return(0);
4514: }
4516: /*@C
4517: SNESGetType - Gets the SNES method type and name (as a string).
4519: Not Collective
4521: Input Parameter:
4522: . snes - nonlinear solver context
4524: Output Parameter:
4525: . type - SNES method (a character string)
4527: Level: intermediate
4529: .keywords: SNES, nonlinear, get, type, name
4530: @*/
4531: PetscErrorCode SNESGetType(SNES snes,SNESType *type)
4532: {
4536: *type = ((PetscObject)snes)->type_name;
4537: return(0);
4538: }
4540: /*@
4541: SNESSetSolution - Sets the solution vector for use by the SNES routines.
4543: Logically Collective on SNES and Vec
4545: Input Parameters:
4546: + snes - the SNES context obtained from SNESCreate()
4547: - u - the solution vector
4549: Level: beginner
4551: .keywords: SNES, set, solution
4552: @*/
4553: PetscErrorCode SNESSetSolution(SNES snes, Vec u)
4554: {
4555: DM dm;
4561: PetscObjectReference((PetscObject) u);
4562: VecDestroy(&snes->vec_sol);
4564: snes->vec_sol = u;
4566: SNESGetDM(snes, &dm);
4567: DMShellSetGlobalVector(dm, u);
4568: return(0);
4569: }
4571: /*@
4572: SNESGetSolution - Returns the vector where the approximate solution is
4573: stored. This is the fine grid solution when using SNESSetGridSequence().
4575: Not Collective, but Vec is parallel if SNES is parallel
4577: Input Parameter:
4578: . snes - the SNES context
4580: Output Parameter:
4581: . x - the solution
4583: Level: intermediate
4585: .keywords: SNES, nonlinear, get, solution
4587: .seealso: SNESGetSolutionUpdate(), SNESGetFunction()
4588: @*/
4589: PetscErrorCode SNESGetSolution(SNES snes,Vec *x)
4590: {
4594: *x = snes->vec_sol;
4595: return(0);
4596: }
4598: /*@
4599: SNESGetSolutionUpdate - Returns the vector where the solution update is
4600: stored.
4602: Not Collective, but Vec is parallel if SNES is parallel
4604: Input Parameter:
4605: . snes - the SNES context
4607: Output Parameter:
4608: . x - the solution update
4610: Level: advanced
4612: .keywords: SNES, nonlinear, get, solution, update
4614: .seealso: SNESGetSolution(), SNESGetFunction()
4615: @*/
4616: PetscErrorCode SNESGetSolutionUpdate(SNES snes,Vec *x)
4617: {
4621: *x = snes->vec_sol_update;
4622: return(0);
4623: }
4625: /*@C
4626: SNESGetFunction - Returns the vector where the function is stored.
4628: Not Collective, but Vec is parallel if SNES is parallel. Collective if Vec is requested, but has not been created yet.
4630: Input Parameter:
4631: . snes - the SNES context
4633: Output Parameter:
4634: + r - the vector that is used to store residuals (or NULL if you don't want it)
4635: . f - the function (or NULL if you don't want it); see SNESFunction for calling sequence details
4636: - ctx - the function context (or NULL if you don't want it)
4638: Level: advanced
4640: Notes: The vector r DOES NOT, in general contain the current value of the SNES nonlinear function
4642: .keywords: SNES, nonlinear, get, function
4644: .seealso: SNESSetFunction(), SNESGetSolution(), SNESFunction
4645: @*/
4646: PetscErrorCode SNESGetFunction(SNES snes,Vec *r,PetscErrorCode (**f)(SNES,Vec,Vec,void*),void **ctx)
4647: {
4649: DM dm;
4653: if (r) {
4654: if (!snes->vec_func) {
4655: if (snes->vec_rhs) {
4656: VecDuplicate(snes->vec_rhs,&snes->vec_func);
4657: } else if (snes->vec_sol) {
4658: VecDuplicate(snes->vec_sol,&snes->vec_func);
4659: } else if (snes->dm) {
4660: DMCreateGlobalVector(snes->dm,&snes->vec_func);
4661: }
4662: }
4663: *r = snes->vec_func;
4664: }
4665: SNESGetDM(snes,&dm);
4666: DMSNESGetFunction(dm,f,ctx);
4667: return(0);
4668: }
4670: /*@C
4671: SNESGetNGS - Returns the NGS function and context.
4673: Input Parameter:
4674: . snes - the SNES context
4676: Output Parameter:
4677: + f - the function (or NULL) see SNESNGSFunction for details
4678: - ctx - the function context (or NULL)
4680: Level: advanced
4682: .keywords: SNES, nonlinear, get, function
4684: .seealso: SNESSetNGS(), SNESGetFunction()
4685: @*/
4687: PetscErrorCode SNESGetNGS (SNES snes, PetscErrorCode (**f)(SNES, Vec, Vec, void*), void ** ctx)
4688: {
4690: DM dm;
4694: SNESGetDM(snes,&dm);
4695: DMSNESGetNGS(dm,f,ctx);
4696: return(0);
4697: }
4699: /*@C
4700: SNESSetOptionsPrefix - Sets the prefix used for searching for all
4701: SNES options in the database.
4703: Logically Collective on SNES
4705: Input Parameter:
4706: + snes - the SNES context
4707: - prefix - the prefix to prepend to all option names
4709: Notes:
4710: A hyphen (-) must NOT be given at the beginning of the prefix name.
4711: The first character of all runtime options is AUTOMATICALLY the hyphen.
4713: Level: advanced
4715: .keywords: SNES, set, options, prefix, database
4717: .seealso: SNESSetFromOptions()
4718: @*/
4719: PetscErrorCode SNESSetOptionsPrefix(SNES snes,const char prefix[])
4720: {
4725: PetscObjectSetOptionsPrefix((PetscObject)snes,prefix);
4726: if (!snes->ksp) {SNESGetKSP(snes,&snes->ksp);}
4727: if (snes->linesearch) {
4728: SNESGetLineSearch(snes,&snes->linesearch);
4729: PetscObjectSetOptionsPrefix((PetscObject)snes->linesearch,prefix);
4730: }
4731: KSPSetOptionsPrefix(snes->ksp,prefix);
4732: return(0);
4733: }
4735: /*@C
4736: SNESAppendOptionsPrefix - Appends to the prefix used for searching for all
4737: SNES options in the database.
4739: Logically Collective on SNES
4741: Input Parameters:
4742: + snes - the SNES context
4743: - prefix - the prefix to prepend to all option names
4745: Notes:
4746: A hyphen (-) must NOT be given at the beginning of the prefix name.
4747: The first character of all runtime options is AUTOMATICALLY the hyphen.
4749: Level: advanced
4751: .keywords: SNES, append, options, prefix, database
4753: .seealso: SNESGetOptionsPrefix()
4754: @*/
4755: PetscErrorCode SNESAppendOptionsPrefix(SNES snes,const char prefix[])
4756: {
4761: PetscObjectAppendOptionsPrefix((PetscObject)snes,prefix);
4762: if (!snes->ksp) {SNESGetKSP(snes,&snes->ksp);}
4763: if (snes->linesearch) {
4764: SNESGetLineSearch(snes,&snes->linesearch);
4765: PetscObjectAppendOptionsPrefix((PetscObject)snes->linesearch,prefix);
4766: }
4767: KSPAppendOptionsPrefix(snes->ksp,prefix);
4768: return(0);
4769: }
4771: /*@C
4772: SNESGetOptionsPrefix - Sets the prefix used for searching for all
4773: SNES options in the database.
4775: Not Collective
4777: Input Parameter:
4778: . snes - the SNES context
4780: Output Parameter:
4781: . prefix - pointer to the prefix string used
4783: Notes:
4784: On the fortran side, the user should pass in a string 'prefix' of
4785: sufficient length to hold the prefix.
4787: Level: advanced
4789: .keywords: SNES, get, options, prefix, database
4791: .seealso: SNESAppendOptionsPrefix()
4792: @*/
4793: PetscErrorCode SNESGetOptionsPrefix(SNES snes,const char *prefix[])
4794: {
4799: PetscObjectGetOptionsPrefix((PetscObject)snes,prefix);
4800: return(0);
4801: }
4804: /*@C
4805: SNESRegister - Adds a method to the nonlinear solver package.
4807: Not collective
4809: Input Parameters:
4810: + name_solver - name of a new user-defined solver
4811: - routine_create - routine to create method context
4813: Notes:
4814: SNESRegister() may be called multiple times to add several user-defined solvers.
4816: Sample usage:
4817: .vb
4818: SNESRegister("my_solver",MySolverCreate);
4819: .ve
4821: Then, your solver can be chosen with the procedural interface via
4822: $ SNESSetType(snes,"my_solver")
4823: or at runtime via the option
4824: $ -snes_type my_solver
4826: Level: advanced
4828: Note: If your function is not being put into a shared library then use SNESRegister() instead
4830: .keywords: SNES, nonlinear, register
4832: .seealso: SNESRegisterAll(), SNESRegisterDestroy()
4834: Level: advanced
4835: @*/
4836: PetscErrorCode SNESRegister(const char sname[],PetscErrorCode (*function)(SNES))
4837: {
4841: SNESInitializePackage();
4842: PetscFunctionListAdd(&SNESList,sname,function);
4843: return(0);
4844: }
4846: PetscErrorCode SNESTestLocalMin(SNES snes)
4847: {
4849: PetscInt N,i,j;
4850: Vec u,uh,fh;
4851: PetscScalar value;
4852: PetscReal norm;
4855: SNESGetSolution(snes,&u);
4856: VecDuplicate(u,&uh);
4857: VecDuplicate(u,&fh);
4859: /* currently only works for sequential */
4860: PetscPrintf(PETSC_COMM_WORLD,"Testing FormFunction() for local min\n");
4861: VecGetSize(u,&N);
4862: for (i=0; i<N; i++) {
4863: VecCopy(u,uh);
4864: PetscPrintf(PETSC_COMM_WORLD,"i = %D\n",i);
4865: for (j=-10; j<11; j++) {
4866: value = PetscSign(j)*PetscExpReal(PetscAbs(j)-10.0);
4867: VecSetValue(uh,i,value,ADD_VALUES);
4868: SNESComputeFunction(snes,uh,fh);
4869: VecNorm(fh,NORM_2,&norm);
4870: PetscPrintf(PETSC_COMM_WORLD," j norm %D %18.16e\n",j,norm);
4871: value = -value;
4872: VecSetValue(uh,i,value,ADD_VALUES);
4873: }
4874: }
4875: VecDestroy(&uh);
4876: VecDestroy(&fh);
4877: return(0);
4878: }
4880: /*@
4881: SNESKSPSetUseEW - Sets SNES use Eisenstat-Walker method for
4882: computing relative tolerance for linear solvers within an inexact
4883: Newton method.
4885: Logically Collective on SNES
4887: Input Parameters:
4888: + snes - SNES context
4889: - flag - PETSC_TRUE or PETSC_FALSE
4891: Options Database:
4892: + -snes_ksp_ew - use Eisenstat-Walker method for determining linear system convergence
4893: . -snes_ksp_ew_version ver - version of Eisenstat-Walker method
4894: . -snes_ksp_ew_rtol0 <rtol0> - Sets rtol0
4895: . -snes_ksp_ew_rtolmax <rtolmax> - Sets rtolmax
4896: . -snes_ksp_ew_gamma <gamma> - Sets gamma
4897: . -snes_ksp_ew_alpha <alpha> - Sets alpha
4898: . -snes_ksp_ew_alpha2 <alpha2> - Sets alpha2
4899: - -snes_ksp_ew_threshold <threshold> - Sets threshold
4901: Notes:
4902: Currently, the default is to use a constant relative tolerance for
4903: the inner linear solvers. Alternatively, one can use the
4904: Eisenstat-Walker method, where the relative convergence tolerance
4905: is reset at each Newton iteration according progress of the nonlinear
4906: solver.
4908: Level: advanced
4910: Reference:
4911: S. C. Eisenstat and H. F. Walker, "Choosing the forcing terms in an
4912: inexact Newton method", SISC 17 (1), pp.16-32, 1996.
4914: .keywords: SNES, KSP, Eisenstat, Walker, convergence, test, inexact, Newton
4916: .seealso: SNESKSPGetUseEW(), SNESKSPGetParametersEW(), SNESKSPSetParametersEW()
4917: @*/
4918: PetscErrorCode SNESKSPSetUseEW(SNES snes,PetscBool flag)
4919: {
4923: snes->ksp_ewconv = flag;
4924: return(0);
4925: }
4927: /*@
4928: SNESKSPGetUseEW - Gets if SNES is using Eisenstat-Walker method
4929: for computing relative tolerance for linear solvers within an
4930: inexact Newton method.
4932: Not Collective
4934: Input Parameter:
4935: . snes - SNES context
4937: Output Parameter:
4938: . flag - PETSC_TRUE or PETSC_FALSE
4940: Notes:
4941: Currently, the default is to use a constant relative tolerance for
4942: the inner linear solvers. Alternatively, one can use the
4943: Eisenstat-Walker method, where the relative convergence tolerance
4944: is reset at each Newton iteration according progress of the nonlinear
4945: solver.
4947: Level: advanced
4949: Reference:
4950: S. C. Eisenstat and H. F. Walker, "Choosing the forcing terms in an
4951: inexact Newton method", SISC 17 (1), pp.16-32, 1996.
4953: .keywords: SNES, KSP, Eisenstat, Walker, convergence, test, inexact, Newton
4955: .seealso: SNESKSPSetUseEW(), SNESKSPGetParametersEW(), SNESKSPSetParametersEW()
4956: @*/
4957: PetscErrorCode SNESKSPGetUseEW(SNES snes, PetscBool *flag)
4958: {
4962: *flag = snes->ksp_ewconv;
4963: return(0);
4964: }
4966: /*@
4967: SNESKSPSetParametersEW - Sets parameters for Eisenstat-Walker
4968: convergence criteria for the linear solvers within an inexact
4969: Newton method.
4971: Logically Collective on SNES
4973: Input Parameters:
4974: + snes - SNES context
4975: . version - version 1, 2 (default is 2) or 3
4976: . rtol_0 - initial relative tolerance (0 <= rtol_0 < 1)
4977: . rtol_max - maximum relative tolerance (0 <= rtol_max < 1)
4978: . gamma - multiplicative factor for version 2 rtol computation
4979: (0 <= gamma2 <= 1)
4980: . alpha - power for version 2 rtol computation (1 < alpha <= 2)
4981: . alpha2 - power for safeguard
4982: - threshold - threshold for imposing safeguard (0 < threshold < 1)
4984: Note:
4985: Version 3 was contributed by Luis Chacon, June 2006.
4987: Use PETSC_DEFAULT to retain the default for any of the parameters.
4989: Level: advanced
4991: Reference:
4992: S. C. Eisenstat and H. F. Walker, "Choosing the forcing terms in an
4993: inexact Newton method", Utah State University Math. Stat. Dept. Res.
4994: Report 6/94/75, June, 1994, to appear in SIAM J. Sci. Comput.
4996: .keywords: SNES, KSP, Eisenstat, Walker, set, parameters
4998: .seealso: SNESKSPSetUseEW(), SNESKSPGetUseEW(), SNESKSPGetParametersEW()
4999: @*/
5000: PetscErrorCode SNESKSPSetParametersEW(SNES snes,PetscInt version,PetscReal rtol_0,PetscReal rtol_max,PetscReal gamma,PetscReal alpha,PetscReal alpha2,PetscReal threshold)
5001: {
5002: SNESKSPEW *kctx;
5006: kctx = (SNESKSPEW*)snes->kspconvctx;
5007: if (!kctx) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"No Eisenstat-Walker context existing");
5016: if (version != PETSC_DEFAULT) kctx->version = version;
5017: if (rtol_0 != PETSC_DEFAULT) kctx->rtol_0 = rtol_0;
5018: if (rtol_max != PETSC_DEFAULT) kctx->rtol_max = rtol_max;
5019: if (gamma != PETSC_DEFAULT) kctx->gamma = gamma;
5020: if (alpha != PETSC_DEFAULT) kctx->alpha = alpha;
5021: if (alpha2 != PETSC_DEFAULT) kctx->alpha2 = alpha2;
5022: if (threshold != PETSC_DEFAULT) kctx->threshold = threshold;
5024: if (kctx->version < 1 || kctx->version > 3) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Only versions 1, 2 and 3 are supported: %D",kctx->version);
5025: if (kctx->rtol_0 < 0.0 || kctx->rtol_0 >= 1.0) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"0.0 <= rtol_0 < 1.0: %g",(double)kctx->rtol_0);
5026: if (kctx->rtol_max < 0.0 || kctx->rtol_max >= 1.0) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"0.0 <= rtol_max (%g) < 1.0\n",(double)kctx->rtol_max);
5027: if (kctx->gamma < 0.0 || kctx->gamma > 1.0) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"0.0 <= gamma (%g) <= 1.0\n",(double)kctx->gamma);
5028: if (kctx->alpha <= 1.0 || kctx->alpha > 2.0) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"1.0 < alpha (%g) <= 2.0\n",(double)kctx->alpha);
5029: if (kctx->threshold <= 0.0 || kctx->threshold >= 1.0) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"0.0 < threshold (%g) < 1.0\n",(double)kctx->threshold);
5030: return(0);
5031: }
5033: /*@
5034: SNESKSPGetParametersEW - Gets parameters for Eisenstat-Walker
5035: convergence criteria for the linear solvers within an inexact
5036: Newton method.
5038: Not Collective
5040: Input Parameters:
5041: snes - SNES context
5043: Output Parameters:
5044: + version - version 1, 2 (default is 2) or 3
5045: . rtol_0 - initial relative tolerance (0 <= rtol_0 < 1)
5046: . rtol_max - maximum relative tolerance (0 <= rtol_max < 1)
5047: . gamma - multiplicative factor for version 2 rtol computation (0 <= gamma2 <= 1)
5048: . alpha - power for version 2 rtol computation (1 < alpha <= 2)
5049: . alpha2 - power for safeguard
5050: - threshold - threshold for imposing safeguard (0 < threshold < 1)
5052: Level: advanced
5054: .keywords: SNES, KSP, Eisenstat, Walker, get, parameters
5056: .seealso: SNESKSPSetUseEW(), SNESKSPGetUseEW(), SNESKSPSetParametersEW()
5057: @*/
5058: PetscErrorCode SNESKSPGetParametersEW(SNES snes,PetscInt *version,PetscReal *rtol_0,PetscReal *rtol_max,PetscReal *gamma,PetscReal *alpha,PetscReal *alpha2,PetscReal *threshold)
5059: {
5060: SNESKSPEW *kctx;
5064: kctx = (SNESKSPEW*)snes->kspconvctx;
5065: if (!kctx) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"No Eisenstat-Walker context existing");
5066: if (version) *version = kctx->version;
5067: if (rtol_0) *rtol_0 = kctx->rtol_0;
5068: if (rtol_max) *rtol_max = kctx->rtol_max;
5069: if (gamma) *gamma = kctx->gamma;
5070: if (alpha) *alpha = kctx->alpha;
5071: if (alpha2) *alpha2 = kctx->alpha2;
5072: if (threshold) *threshold = kctx->threshold;
5073: return(0);
5074: }
5076: PetscErrorCode KSPPreSolve_SNESEW(KSP ksp, Vec b, Vec x, SNES snes)
5077: {
5079: SNESKSPEW *kctx = (SNESKSPEW*)snes->kspconvctx;
5080: PetscReal rtol = PETSC_DEFAULT,stol;
5083: if (!snes->ksp_ewconv) return(0);
5084: if (!snes->iter) {
5085: rtol = kctx->rtol_0; /* first time in, so use the original user rtol */
5086: VecNorm(snes->vec_func,NORM_2,&kctx->norm_first);
5087: }
5088: else {
5089: if (kctx->version == 1) {
5090: rtol = (snes->norm - kctx->lresid_last)/kctx->norm_last;
5091: if (rtol < 0.0) rtol = -rtol;
5092: stol = PetscPowReal(kctx->rtol_last,kctx->alpha2);
5093: if (stol > kctx->threshold) rtol = PetscMax(rtol,stol);
5094: } else if (kctx->version == 2) {
5095: rtol = kctx->gamma * PetscPowReal(snes->norm/kctx->norm_last,kctx->alpha);
5096: stol = kctx->gamma * PetscPowReal(kctx->rtol_last,kctx->alpha);
5097: if (stol > kctx->threshold) rtol = PetscMax(rtol,stol);
5098: } else if (kctx->version == 3) { /* contributed by Luis Chacon, June 2006. */
5099: rtol = kctx->gamma * PetscPowReal(snes->norm/kctx->norm_last,kctx->alpha);
5100: /* safeguard: avoid sharp decrease of rtol */
5101: stol = kctx->gamma*PetscPowReal(kctx->rtol_last,kctx->alpha);
5102: stol = PetscMax(rtol,stol);
5103: rtol = PetscMin(kctx->rtol_0,stol);
5104: /* safeguard: avoid oversolving */
5105: stol = kctx->gamma*(kctx->norm_first*snes->rtol)/snes->norm;
5106: stol = PetscMax(rtol,stol);
5107: rtol = PetscMin(kctx->rtol_0,stol);
5108: } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Only versions 1, 2 or 3 are supported: %D",kctx->version);
5109: }
5110: /* safeguard: avoid rtol greater than one */
5111: rtol = PetscMin(rtol,kctx->rtol_max);
5112: KSPSetTolerances(ksp,rtol,PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT);
5113: PetscInfo3(snes,"iter %D, Eisenstat-Walker (version %D) KSP rtol=%g\n",snes->iter,kctx->version,(double)rtol);
5114: return(0);
5115: }
5117: PetscErrorCode KSPPostSolve_SNESEW(KSP ksp, Vec b, Vec x, SNES snes)
5118: {
5120: SNESKSPEW *kctx = (SNESKSPEW*)snes->kspconvctx;
5121: PCSide pcside;
5122: Vec lres;
5125: if (!snes->ksp_ewconv) return(0);
5126: KSPGetTolerances(ksp,&kctx->rtol_last,0,0,0);
5127: kctx->norm_last = snes->norm;
5128: if (kctx->version == 1) {
5129: PC pc;
5130: PetscBool isNone;
5132: KSPGetPC(ksp, &pc);
5133: PetscObjectTypeCompare((PetscObject) pc, PCNONE, &isNone);
5134: KSPGetPCSide(ksp,&pcside);
5135: if (pcside == PC_RIGHT || isNone) { /* XXX Should we also test KSP_UNPRECONDITIONED_NORM ? */
5136: /* KSP residual is true linear residual */
5137: KSPGetResidualNorm(ksp,&kctx->lresid_last);
5138: } else {
5139: /* KSP residual is preconditioned residual */
5140: /* compute true linear residual norm */
5141: VecDuplicate(b,&lres);
5142: MatMult(snes->jacobian,x,lres);
5143: VecAYPX(lres,-1.0,b);
5144: VecNorm(lres,NORM_2,&kctx->lresid_last);
5145: VecDestroy(&lres);
5146: }
5147: }
5148: return(0);
5149: }
5151: /*@
5152: SNESGetKSP - Returns the KSP context for a SNES solver.
5154: Not Collective, but if SNES object is parallel, then KSP object is parallel
5156: Input Parameter:
5157: . snes - the SNES context
5159: Output Parameter:
5160: . ksp - the KSP context
5162: Notes:
5163: The user can then directly manipulate the KSP context to set various
5164: options, etc. Likewise, the user can then extract and manipulate the
5165: PC contexts as well.
5167: Level: beginner
5169: .keywords: SNES, nonlinear, get, KSP, context
5171: .seealso: KSPGetPC(), SNESCreate(), KSPCreate(), SNESSetKSP()
5172: @*/
5173: PetscErrorCode SNESGetKSP(SNES snes,KSP *ksp)
5174: {
5181: if (!snes->ksp) {
5182: PetscBool monitor = PETSC_FALSE;
5184: KSPCreate(PetscObjectComm((PetscObject)snes),&snes->ksp);
5185: PetscObjectIncrementTabLevel((PetscObject)snes->ksp,(PetscObject)snes,1);
5186: PetscLogObjectParent((PetscObject)snes,(PetscObject)snes->ksp);
5188: KSPSetPreSolve(snes->ksp,(PetscErrorCode (*)(KSP,Vec,Vec,void*))KSPPreSolve_SNESEW,snes);
5189: KSPSetPostSolve(snes->ksp,(PetscErrorCode (*)(KSP,Vec,Vec,void*))KSPPostSolve_SNESEW,snes);
5191: PetscOptionsGetBool(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-ksp_monitor_snes",&monitor,NULL);
5192: if (monitor) {
5193: KSPMonitorSet(snes->ksp,KSPMonitorSNES,snes,NULL);
5194: }
5195: monitor = PETSC_FALSE;
5196: PetscOptionsGetBool(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-ksp_monitor_snes_lg",&monitor,NULL);
5197: if (monitor) {
5198: PetscObject *objs;
5199: KSPMonitorSNESLGResidualNormCreate(PetscObjectComm((PetscObject)snes),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,600,600,&objs);
5200: objs[0] = (PetscObject) snes;
5201: KSPMonitorSet(snes->ksp,(PetscErrorCode (*)(KSP,PetscInt,PetscReal,void*))KSPMonitorSNESLGResidualNorm,objs,(PetscErrorCode (*)(void**))KSPMonitorSNESLGResidualNormDestroy);
5202: }
5203: }
5204: *ksp = snes->ksp;
5205: return(0);
5206: }
5209: #include <petsc/private/dmimpl.h>
5210: /*@
5211: SNESSetDM - Sets the DM that may be used by some nonlinear solvers or their underlying preconditioners
5213: Logically Collective on SNES
5215: Input Parameters:
5216: + snes - the nonlinear solver context
5217: - dm - the dm, cannot be NULL
5219: Notes:
5220: A DM can only be used for solving one problem at a time because information about the problem is stored on the DM,
5221: even when not using interfaces like DMSNESSetFunction(). Use DMClone() to get a distinct DM when solving different
5222: problems using the same function space.
5224: Level: intermediate
5226: .seealso: SNESGetDM(), KSPSetDM(), KSPGetDM()
5227: @*/
5228: PetscErrorCode SNESSetDM(SNES snes,DM dm)
5229: {
5231: KSP ksp;
5232: DMSNES sdm;
5237: PetscObjectReference((PetscObject)dm);
5238: if (snes->dm) { /* Move the DMSNES context over to the new DM unless the new DM already has one */
5239: if (snes->dm->dmsnes && !dm->dmsnes) {
5240: DMCopyDMSNES(snes->dm,dm);
5241: DMGetDMSNES(snes->dm,&sdm);
5242: if (sdm->originaldm == snes->dm) sdm->originaldm = dm; /* Grant write privileges to the replacement DM */
5243: }
5244: DMCoarsenHookRemove(snes->dm,DMCoarsenHook_SNESVecSol,DMRestrictHook_SNESVecSol,snes);
5245: DMDestroy(&snes->dm);
5246: }
5247: snes->dm = dm;
5248: snes->dmAuto = PETSC_FALSE;
5250: SNESGetKSP(snes,&ksp);
5251: KSPSetDM(ksp,dm);
5252: KSPSetDMActive(ksp,PETSC_FALSE);
5253: if (snes->npc) {
5254: SNESSetDM(snes->npc, snes->dm);
5255: SNESSetNPCSide(snes,snes->npcside);
5256: }
5257: return(0);
5258: }
5260: /*@
5261: SNESGetDM - Gets the DM that may be used by some preconditioners
5263: Not Collective but DM obtained is parallel on SNES
5265: Input Parameter:
5266: . snes - the preconditioner context
5268: Output Parameter:
5269: . dm - the dm
5271: Level: intermediate
5273: .seealso: SNESSetDM(), KSPSetDM(), KSPGetDM()
5274: @*/
5275: PetscErrorCode SNESGetDM(SNES snes,DM *dm)
5276: {
5281: if (!snes->dm) {
5282: DMShellCreate(PetscObjectComm((PetscObject)snes),&snes->dm);
5283: snes->dmAuto = PETSC_TRUE;
5284: }
5285: *dm = snes->dm;
5286: return(0);
5287: }
5289: /*@
5290: SNESSetNPC - Sets the nonlinear preconditioner to be used.
5292: Collective on SNES
5294: Input Parameters:
5295: + snes - iterative context obtained from SNESCreate()
5296: - pc - the preconditioner object
5298: Notes:
5299: Use SNESGetNPC() to retrieve the preconditioner context (for example,
5300: to configure it using the API).
5302: Level: developer
5304: .keywords: SNES, set, precondition
5305: .seealso: SNESGetNPC(), SNESHasNPC()
5306: @*/
5307: PetscErrorCode SNESSetNPC(SNES snes, SNES pc)
5308: {
5315: PetscObjectReference((PetscObject) pc);
5316: SNESDestroy(&snes->npc);
5317: snes->npc = pc;
5318: PetscLogObjectParent((PetscObject)snes, (PetscObject)snes->npc);
5319: return(0);
5320: }
5322: /*@
5323: SNESGetNPC - Creates a nonlinear preconditioning solver (SNES) to be used to precondition the nonlinear solver.
5325: Not Collective
5327: Input Parameter:
5328: . snes - iterative context obtained from SNESCreate()
5330: Output Parameter:
5331: . pc - preconditioner context
5333: Notes:
5334: If a SNES was previously set with SNESSetNPC() then that SNES is returned.
5336: Level: developer
5338: .keywords: SNES, get, preconditioner
5339: .seealso: SNESSetNPC(), SNESHasNPC()
5340: @*/
5341: PetscErrorCode SNESGetNPC(SNES snes, SNES *pc)
5342: {
5344: const char *optionsprefix;
5349: if (!snes->npc) {
5350: SNESCreate(PetscObjectComm((PetscObject)snes),&snes->npc);
5351: PetscObjectIncrementTabLevel((PetscObject)snes->npc,(PetscObject)snes,1);
5352: PetscLogObjectParent((PetscObject)snes,(PetscObject)snes->npc);
5353: SNESGetOptionsPrefix(snes,&optionsprefix);
5354: SNESSetOptionsPrefix(snes->npc,optionsprefix);
5355: SNESAppendOptionsPrefix(snes->npc,"npc_");
5356: SNESSetCountersReset(snes->npc,PETSC_FALSE);
5357: }
5358: *pc = snes->npc;
5359: return(0);
5360: }
5362: /*@
5363: SNESHasNPC - Returns whether a nonlinear preconditioner exists
5365: Not Collective
5367: Input Parameter:
5368: . snes - iterative context obtained from SNESCreate()
5370: Output Parameter:
5371: . has_npc - whether the SNES has an NPC or not
5373: Level: developer
5375: .keywords: SNES, has, preconditioner
5376: .seealso: SNESSetNPC(), SNESGetNPC()
5377: @*/
5378: PetscErrorCode SNESHasNPC(SNES snes, PetscBool *has_npc)
5379: {
5382: *has_npc = (PetscBool) (snes->npc ? PETSC_TRUE : PETSC_FALSE);
5383: return(0);
5384: }
5386: /*@
5387: SNESSetNPCSide - Sets the preconditioning side.
5389: Logically Collective on SNES
5391: Input Parameter:
5392: . snes - iterative context obtained from SNESCreate()
5394: Output Parameter:
5395: . side - the preconditioning side, where side is one of
5396: .vb
5397: PC_LEFT - left preconditioning
5398: PC_RIGHT - right preconditioning (default for most nonlinear solvers)
5399: .ve
5401: Options Database Keys:
5402: . -snes_pc_side <right,left>
5404: Notes:
5405: SNESNRICHARDSON and SNESNCG only support left preconditioning.
5407: Level: intermediate
5409: .keywords: SNES, set, right, left, side, preconditioner, flag
5411: .seealso: SNESGetNPCSide(), KSPSetPCSide()
5412: @*/
5413: PetscErrorCode SNESSetNPCSide(SNES snes,PCSide side)
5414: {
5418: snes->npcside= side;
5419: return(0);
5420: }
5422: /*@
5423: SNESGetNPCSide - Gets the preconditioning side.
5425: Not Collective
5427: Input Parameter:
5428: . snes - iterative context obtained from SNESCreate()
5430: Output Parameter:
5431: . side - the preconditioning side, where side is one of
5432: .vb
5433: PC_LEFT - left preconditioning
5434: PC_RIGHT - right preconditioning (default for most nonlinear solvers)
5435: .ve
5437: Level: intermediate
5439: .keywords: SNES, get, right, left, side, preconditioner, flag
5441: .seealso: SNESSetNPCSide(), KSPGetPCSide()
5442: @*/
5443: PetscErrorCode SNESGetNPCSide(SNES snes,PCSide *side)
5444: {
5448: *side = snes->npcside;
5449: return(0);
5450: }
5452: /*@
5453: SNESSetLineSearch - Sets the linesearch on the SNES instance.
5455: Collective on SNES
5457: Input Parameters:
5458: + snes - iterative context obtained from SNESCreate()
5459: - linesearch - the linesearch object
5461: Notes:
5462: Use SNESGetLineSearch() to retrieve the preconditioner context (for example,
5463: to configure it using the API).
5465: Level: developer
5467: .keywords: SNES, set, linesearch
5468: .seealso: SNESGetLineSearch()
5469: @*/
5470: PetscErrorCode SNESSetLineSearch(SNES snes, SNESLineSearch linesearch)
5471: {
5478: PetscObjectReference((PetscObject) linesearch);
5479: SNESLineSearchDestroy(&snes->linesearch);
5481: snes->linesearch = linesearch;
5483: PetscLogObjectParent((PetscObject)snes, (PetscObject)snes->linesearch);
5484: return(0);
5485: }
5487: /*@
5488: SNESGetLineSearch - Returns a pointer to the line search context set with SNESSetLineSearch()
5489: or creates a default line search instance associated with the SNES and returns it.
5491: Not Collective
5493: Input Parameter:
5494: . snes - iterative context obtained from SNESCreate()
5496: Output Parameter:
5497: . linesearch - linesearch context
5499: Level: beginner
5501: .keywords: SNES, get, linesearch
5502: .seealso: SNESSetLineSearch(), SNESLineSearchCreate()
5503: @*/
5504: PetscErrorCode SNESGetLineSearch(SNES snes, SNESLineSearch *linesearch)
5505: {
5507: const char *optionsprefix;
5512: if (!snes->linesearch) {
5513: SNESGetOptionsPrefix(snes, &optionsprefix);
5514: SNESLineSearchCreate(PetscObjectComm((PetscObject)snes), &snes->linesearch);
5515: SNESLineSearchSetSNES(snes->linesearch, snes);
5516: SNESLineSearchAppendOptionsPrefix(snes->linesearch, optionsprefix);
5517: PetscObjectIncrementTabLevel((PetscObject) snes->linesearch, (PetscObject) snes, 1);
5518: PetscLogObjectParent((PetscObject)snes, (PetscObject)snes->linesearch);
5519: }
5520: *linesearch = snes->linesearch;
5521: return(0);
5522: }
5524: #if defined(PETSC_HAVE_MATLAB_ENGINE)
5525: #include <mex.h>
5527: typedef struct {char *funcname; mxArray *ctx;} SNESMatlabContext;
5529: /*
5530: SNESComputeFunction_Matlab - Calls the function that has been set with SNESSetFunctionMatlab().
5532: Collective on SNES
5534: Input Parameters:
5535: + snes - the SNES context
5536: - x - input vector
5538: Output Parameter:
5539: . y - function vector, as set by SNESSetFunction()
5541: Notes:
5542: SNESComputeFunction() is typically used within nonlinear solvers
5543: implementations, so most users would not generally call this routine
5544: themselves.
5546: Level: developer
5548: .keywords: SNES, nonlinear, compute, function
5550: .seealso: SNESSetFunction(), SNESGetFunction()
5551: */
5552: PetscErrorCode SNESComputeFunction_Matlab(SNES snes,Vec x,Vec y, void *ctx)
5553: {
5554: PetscErrorCode ierr;
5555: SNESMatlabContext *sctx = (SNESMatlabContext*)ctx;
5556: int nlhs = 1,nrhs = 5;
5557: mxArray *plhs[1],*prhs[5];
5558: long long int lx = 0,ly = 0,ls = 0;
5567: /* call Matlab function in ctx with arguments x and y */
5569: PetscMemcpy(&ls,&snes,sizeof(snes));
5570: PetscMemcpy(&lx,&x,sizeof(x));
5571: PetscMemcpy(&ly,&y,sizeof(x));
5572: prhs[0] = mxCreateDoubleScalar((double)ls);
5573: prhs[1] = mxCreateDoubleScalar((double)lx);
5574: prhs[2] = mxCreateDoubleScalar((double)ly);
5575: prhs[3] = mxCreateString(sctx->funcname);
5576: prhs[4] = sctx->ctx;
5577: mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscSNESComputeFunctionInternal");
5578: mxGetScalar(plhs[0]);
5579: mxDestroyArray(prhs[0]);
5580: mxDestroyArray(prhs[1]);
5581: mxDestroyArray(prhs[2]);
5582: mxDestroyArray(prhs[3]);
5583: mxDestroyArray(plhs[0]);
5584: return(0);
5585: }
5587: /*
5588: SNESSetFunctionMatlab - Sets the function evaluation routine and function
5589: vector for use by the SNES routines in solving systems of nonlinear
5590: equations from MATLAB. Here the function is a string containing the name of a MATLAB function
5592: Logically Collective on SNES
5594: Input Parameters:
5595: + snes - the SNES context
5596: . r - vector to store function value
5597: - f - function evaluation routine
5599: Notes:
5600: The Newton-like methods typically solve linear systems of the form
5601: $ f'(x) x = -f(x),
5602: where f'(x) denotes the Jacobian matrix and f(x) is the function.
5604: Level: beginner
5606: Developer Note: This bleeds the allocated memory SNESMatlabContext *sctx;
5608: .keywords: SNES, nonlinear, set, function
5610: .seealso: SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESSetFunction()
5611: */
5612: PetscErrorCode SNESSetFunctionMatlab(SNES snes,Vec r,const char *f,mxArray *ctx)
5613: {
5614: PetscErrorCode ierr;
5615: SNESMatlabContext *sctx;
5618: /* currently sctx is memory bleed */
5619: PetscNew(&sctx);
5620: PetscStrallocpy(f,&sctx->funcname);
5621: /*
5622: This should work, but it doesn't
5623: sctx->ctx = ctx;
5624: mexMakeArrayPersistent(sctx->ctx);
5625: */
5626: sctx->ctx = mxDuplicateArray(ctx);
5627: SNESSetFunction(snes,r,SNESComputeFunction_Matlab,sctx);
5628: return(0);
5629: }
5631: /*
5632: SNESComputeJacobian_Matlab - Calls the function that has been set with SNESSetJacobianMatlab().
5634: Collective on SNES
5636: Input Parameters:
5637: + snes - the SNES context
5638: . x - input vector
5639: . A, B - the matrices
5640: - ctx - user context
5642: Level: developer
5644: .keywords: SNES, nonlinear, compute, function
5646: .seealso: SNESSetFunction(), SNESGetFunction()
5647: @*/
5648: PetscErrorCode SNESComputeJacobian_Matlab(SNES snes,Vec x,Mat A,Mat B,void *ctx)
5649: {
5650: PetscErrorCode ierr;
5651: SNESMatlabContext *sctx = (SNESMatlabContext*)ctx;
5652: int nlhs = 2,nrhs = 6;
5653: mxArray *plhs[2],*prhs[6];
5654: long long int lx = 0,lA = 0,ls = 0, lB = 0;
5660: /* call Matlab function in ctx with arguments x and y */
5662: PetscMemcpy(&ls,&snes,sizeof(snes));
5663: PetscMemcpy(&lx,&x,sizeof(x));
5664: PetscMemcpy(&lA,A,sizeof(x));
5665: PetscMemcpy(&lB,B,sizeof(x));
5666: prhs[0] = mxCreateDoubleScalar((double)ls);
5667: prhs[1] = mxCreateDoubleScalar((double)lx);
5668: prhs[2] = mxCreateDoubleScalar((double)lA);
5669: prhs[3] = mxCreateDoubleScalar((double)lB);
5670: prhs[4] = mxCreateString(sctx->funcname);
5671: prhs[5] = sctx->ctx;
5672: mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscSNESComputeJacobianInternal");
5673: mxGetScalar(plhs[0]);
5674: mxDestroyArray(prhs[0]);
5675: mxDestroyArray(prhs[1]);
5676: mxDestroyArray(prhs[2]);
5677: mxDestroyArray(prhs[3]);
5678: mxDestroyArray(prhs[4]);
5679: mxDestroyArray(plhs[0]);
5680: mxDestroyArray(plhs[1]);
5681: return(0);
5682: }
5684: /*
5685: SNESSetJacobianMatlab - Sets the Jacobian function evaluation routine and two empty Jacobian matrices
5686: vector for use by the SNES routines in solving systems of nonlinear
5687: equations from MATLAB. Here the function is a string containing the name of a MATLAB function
5689: Logically Collective on SNES
5691: Input Parameters:
5692: + snes - the SNES context
5693: . A,B - Jacobian matrices
5694: . J - function evaluation routine
5695: - ctx - user context
5697: Level: developer
5699: Developer Note: This bleeds the allocated memory SNESMatlabContext *sctx;
5701: .keywords: SNES, nonlinear, set, function
5703: .seealso: SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESSetFunction(), J
5704: */
5705: PetscErrorCode SNESSetJacobianMatlab(SNES snes,Mat A,Mat B,const char *J,mxArray *ctx)
5706: {
5707: PetscErrorCode ierr;
5708: SNESMatlabContext *sctx;
5711: /* currently sctx is memory bleed */
5712: PetscNew(&sctx);
5713: PetscStrallocpy(J,&sctx->funcname);
5714: /*
5715: This should work, but it doesn't
5716: sctx->ctx = ctx;
5717: mexMakeArrayPersistent(sctx->ctx);
5718: */
5719: sctx->ctx = mxDuplicateArray(ctx);
5720: SNESSetJacobian(snes,A,B,SNESComputeJacobian_Matlab,sctx);
5721: return(0);
5722: }
5724: /*
5725: SNESMonitor_Matlab - Calls the function that has been set with SNESMonitorSetMatlab().
5727: Collective on SNES
5729: .seealso: SNESSetFunction(), SNESGetFunction()
5730: @*/
5731: PetscErrorCode SNESMonitor_Matlab(SNES snes,PetscInt it, PetscReal fnorm, void *ctx)
5732: {
5733: PetscErrorCode ierr;
5734: SNESMatlabContext *sctx = (SNESMatlabContext*)ctx;
5735: int nlhs = 1,nrhs = 6;
5736: mxArray *plhs[1],*prhs[6];
5737: long long int lx = 0,ls = 0;
5738: Vec x = snes->vec_sol;
5743: PetscMemcpy(&ls,&snes,sizeof(snes));
5744: PetscMemcpy(&lx,&x,sizeof(x));
5745: prhs[0] = mxCreateDoubleScalar((double)ls);
5746: prhs[1] = mxCreateDoubleScalar((double)it);
5747: prhs[2] = mxCreateDoubleScalar((double)fnorm);
5748: prhs[3] = mxCreateDoubleScalar((double)lx);
5749: prhs[4] = mxCreateString(sctx->funcname);
5750: prhs[5] = sctx->ctx;
5751: mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscSNESMonitorInternal");
5752: mxGetScalar(plhs[0]);
5753: mxDestroyArray(prhs[0]);
5754: mxDestroyArray(prhs[1]);
5755: mxDestroyArray(prhs[2]);
5756: mxDestroyArray(prhs[3]);
5757: mxDestroyArray(prhs[4]);
5758: mxDestroyArray(plhs[0]);
5759: return(0);
5760: }
5762: /*
5763: SNESMonitorSetMatlab - Sets the monitor function from MATLAB
5765: Level: developer
5767: Developer Note: This bleeds the allocated memory SNESMatlabContext *sctx;
5769: .keywords: SNES, nonlinear, set, function
5771: .seealso: SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESSetFunction()
5772: */
5773: PetscErrorCode SNESMonitorSetMatlab(SNES snes,const char *f,mxArray *ctx)
5774: {
5775: PetscErrorCode ierr;
5776: SNESMatlabContext *sctx;
5779: /* currently sctx is memory bleed */
5780: PetscNew(&sctx);
5781: PetscStrallocpy(f,&sctx->funcname);
5782: /*
5783: This should work, but it doesn't
5784: sctx->ctx = ctx;
5785: mexMakeArrayPersistent(sctx->ctx);
5786: */
5787: sctx->ctx = mxDuplicateArray(ctx);
5788: SNESMonitorSet(snes,SNESMonitor_Matlab,sctx,NULL);
5789: return(0);
5790: }
5792: #endif