Actual source code: snes.c
petsc-3.10.5 2019-03-28
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 || complete_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: if (mviewer) { PetscViewerDestroy(&mviewer); }
2456: PetscViewerASCIISetTab(viewer,tabs);
2457: return(0);
2458: }
2460: /*@
2461: SNESComputeJacobian - Computes the Jacobian matrix that has been set with SNESSetJacobian().
2463: Collective on SNES and Mat
2465: Input Parameters:
2466: + snes - the SNES context
2467: - x - input vector
2469: Output Parameters:
2470: + A - Jacobian matrix
2471: - B - optional preconditioning matrix
2473: Options Database Keys:
2474: + -snes_lag_preconditioner <lag>
2475: . -snes_lag_jacobian <lag>
2476: . -snes_test_jacobian - compare the user provided Jacobian with one compute via finite differences to check for errors
2477: . -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
2478: . -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
2479: . -snes_compare_explicit - Compare the computed Jacobian to the finite difference Jacobian and output the differences
2480: . -snes_compare_explicit_draw - Compare the computed Jacobian to the finite difference Jacobian and draw the result
2481: . -snes_compare_explicit_contour - Compare the computed Jacobian to the finite difference Jacobian and draw a contour plot with the result
2482: . -snes_compare_operator - Make the comparison options above use the operator instead of the preconditioning matrix
2483: . -snes_compare_coloring - Compute the finite difference Jacobian using coloring and display norms of difference
2484: . -snes_compare_coloring_display - Compute the finite differece Jacobian using coloring and display verbose differences
2485: . -snes_compare_coloring_threshold - Display only those matrix entries that differ by more than a given threshold
2486: . -snes_compare_coloring_threshold_atol - Absolute tolerance for difference in matrix entries to be displayed by -snes_compare_coloring_threshold
2487: . -snes_compare_coloring_threshold_rtol - Relative tolerance for difference in matrix entries to be displayed by -snes_compare_coloring_threshold
2488: . -snes_compare_coloring_draw - Compute the finite differece Jacobian using coloring and draw differences
2489: - -snes_compare_coloring_draw_contour - Compute the finite differece Jacobian using coloring and show contours of matrices and differences
2492: Notes:
2493: Most users should not need to explicitly call this routine, as it
2494: is used internally within the nonlinear solvers.
2496: Developer Notes:
2497: 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
2498: for with the SNESType of test that has been removed.
2500: Level: developer
2502: .keywords: SNES, compute, Jacobian, matrix
2504: .seealso: SNESSetJacobian(), KSPSetOperators(), MatStructure, SNESSetLagPreconditioner(), SNESSetLagJacobian()
2505: @*/
2506: PetscErrorCode SNESComputeJacobian(SNES snes,Vec X,Mat A,Mat B)
2507: {
2509: PetscBool flag;
2510: DM dm;
2511: DMSNES sdm;
2512: KSP ksp;
2518: VecValidValues(X,2,PETSC_TRUE);
2519: SNESGetDM(snes,&dm);
2520: DMGetDMSNES(dm,&sdm);
2522: if (!sdm->ops->computejacobian) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_USER,"Must call SNESSetJacobian(), DMSNESSetJacobian(), DMDASNESSetJacobianLocal(), etc");
2524: /* make sure that MatAssemblyBegin/End() is called on A matrix if it is matrix free */
2526: if (snes->lagjacobian == -2) {
2527: snes->lagjacobian = -1;
2529: PetscInfo(snes,"Recomputing Jacobian/preconditioner because lag is -2 (means compute Jacobian, but then never again) \n");
2530: } else if (snes->lagjacobian == -1) {
2531: PetscInfo(snes,"Reusing Jacobian/preconditioner because lag is -1\n");
2532: PetscObjectTypeCompare((PetscObject)A,MATMFFD,&flag);
2533: if (flag) {
2534: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
2535: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
2536: }
2537: return(0);
2538: } else if (snes->lagjacobian > 1 && (snes->iter + snes->jac_iter) % snes->lagjacobian) {
2539: PetscInfo2(snes,"Reusing Jacobian/preconditioner because lag is %D and SNES iteration is %D\n",snes->lagjacobian,snes->iter);
2540: PetscObjectTypeCompare((PetscObject)A,MATMFFD,&flag);
2541: if (flag) {
2542: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
2543: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
2544: }
2545: return(0);
2546: }
2547: if (snes->npc && snes->npcside== PC_LEFT) {
2548: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
2549: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
2550: return(0);
2551: }
2553: PetscLogEventBegin(SNES_JacobianEval,snes,X,A,B);
2554: VecLockPush(X);
2555: PetscStackPush("SNES user Jacobian function");
2556: (*sdm->ops->computejacobian)(snes,X,A,B,sdm->jacobianctx);
2557: PetscStackPop;
2558: VecLockPop(X);
2559: PetscLogEventEnd(SNES_JacobianEval,snes,X,A,B);
2561: /* the next line ensures that snes->ksp exists */
2562: SNESGetKSP(snes,&ksp);
2563: if (snes->lagpreconditioner == -2) {
2564: PetscInfo(snes,"Rebuilding preconditioner exactly once since lag is -2\n");
2565: KSPSetReusePreconditioner(snes->ksp,PETSC_FALSE);
2566: snes->lagpreconditioner = -1;
2567: } else if (snes->lagpreconditioner == -1) {
2568: PetscInfo(snes,"Reusing preconditioner because lag is -1\n");
2569: KSPSetReusePreconditioner(snes->ksp,PETSC_TRUE);
2570: } else if (snes->lagpreconditioner > 1 && (snes->iter + snes->pre_iter) % snes->lagpreconditioner) {
2571: PetscInfo2(snes,"Reusing preconditioner because lag is %D and SNES iteration is %D\n",snes->lagpreconditioner,snes->iter);
2572: KSPSetReusePreconditioner(snes->ksp,PETSC_TRUE);
2573: } else {
2574: PetscInfo(snes,"Rebuilding preconditioner\n");
2575: KSPSetReusePreconditioner(snes->ksp,PETSC_FALSE);
2576: }
2578: SNESTestJacobian(snes);
2579: /* make sure user returned a correct Jacobian and preconditioner */
2582: {
2583: PetscBool flag = PETSC_FALSE,flag_draw = PETSC_FALSE,flag_contour = PETSC_FALSE,flag_operator = PETSC_FALSE;
2584: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_explicit",NULL,NULL,&flag);
2585: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_explicit_draw",NULL,NULL,&flag_draw);
2586: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_explicit_draw_contour",NULL,NULL,&flag_contour);
2587: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_operator",NULL,NULL,&flag_operator);
2588: if (flag || flag_draw || flag_contour) {
2589: Mat Bexp_mine = NULL,Bexp,FDexp;
2590: PetscViewer vdraw,vstdout;
2591: PetscBool flg;
2592: if (flag_operator) {
2593: MatComputeExplicitOperator(A,&Bexp_mine);
2594: Bexp = Bexp_mine;
2595: } else {
2596: /* See if the preconditioning matrix can be viewed and added directly */
2597: PetscObjectTypeCompareAny((PetscObject)B,&flg,MATSEQAIJ,MATMPIAIJ,MATSEQDENSE,MATMPIDENSE,MATSEQBAIJ,MATMPIBAIJ,MATSEQSBAIJ,MATMPIBAIJ,"");
2598: if (flg) Bexp = B;
2599: else {
2600: /* If the "preconditioning" matrix is itself MATSHELL or some other type without direct support */
2601: MatComputeExplicitOperator(B,&Bexp_mine);
2602: Bexp = Bexp_mine;
2603: }
2604: }
2605: MatConvert(Bexp,MATSAME,MAT_INITIAL_MATRIX,&FDexp);
2606: SNESComputeJacobianDefault(snes,X,FDexp,FDexp,NULL);
2607: PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)snes),&vstdout);
2608: if (flag_draw || flag_contour) {
2609: PetscViewerDrawOpen(PetscObjectComm((PetscObject)snes),0,"Explicit Jacobians",PETSC_DECIDE,PETSC_DECIDE,300,300,&vdraw);
2610: if (flag_contour) {PetscViewerPushFormat(vdraw,PETSC_VIEWER_DRAW_CONTOUR);}
2611: } else vdraw = NULL;
2612: PetscViewerASCIIPrintf(vstdout,"Explicit %s\n",flag_operator ? "Jacobian" : "preconditioning Jacobian");
2613: if (flag) {MatView(Bexp,vstdout);}
2614: if (vdraw) {MatView(Bexp,vdraw);}
2615: PetscViewerASCIIPrintf(vstdout,"Finite difference Jacobian\n");
2616: if (flag) {MatView(FDexp,vstdout);}
2617: if (vdraw) {MatView(FDexp,vdraw);}
2618: MatAYPX(FDexp,-1.0,Bexp,SAME_NONZERO_PATTERN);
2619: PetscViewerASCIIPrintf(vstdout,"User-provided matrix minus finite difference Jacobian\n");
2620: if (flag) {MatView(FDexp,vstdout);}
2621: if (vdraw) { /* Always use contour for the difference */
2622: PetscViewerPushFormat(vdraw,PETSC_VIEWER_DRAW_CONTOUR);
2623: MatView(FDexp,vdraw);
2624: PetscViewerPopFormat(vdraw);
2625: }
2626: if (flag_contour) {PetscViewerPopFormat(vdraw);}
2627: PetscViewerDestroy(&vdraw);
2628: MatDestroy(&Bexp_mine);
2629: MatDestroy(&FDexp);
2630: }
2631: }
2632: {
2633: PetscBool flag = PETSC_FALSE,flag_display = PETSC_FALSE,flag_draw = PETSC_FALSE,flag_contour = PETSC_FALSE,flag_threshold = PETSC_FALSE;
2634: PetscReal threshold_atol = PETSC_SQRT_MACHINE_EPSILON,threshold_rtol = 10*PETSC_SQRT_MACHINE_EPSILON;
2635: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_coloring",NULL,NULL,&flag);
2636: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_coloring_display",NULL,NULL,&flag_display);
2637: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_coloring_draw",NULL,NULL,&flag_draw);
2638: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_coloring_draw_contour",NULL,NULL,&flag_contour);
2639: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_coloring_threshold",NULL,NULL,&flag_threshold);
2640: if (flag_threshold) {
2641: PetscOptionsGetReal(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-snes_compare_coloring_threshold_rtol",&threshold_rtol,NULL);
2642: PetscOptionsGetReal(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-snes_compare_coloring_threshold_atol",&threshold_atol,NULL);
2643: }
2644: if (flag || flag_display || flag_draw || flag_contour || flag_threshold) {
2645: Mat Bfd;
2646: PetscViewer vdraw,vstdout;
2647: MatColoring coloring;
2648: ISColoring iscoloring;
2649: MatFDColoring matfdcoloring;
2650: PetscErrorCode (*func)(SNES,Vec,Vec,void*);
2651: void *funcctx;
2652: PetscReal norm1,norm2,normmax;
2654: MatDuplicate(B,MAT_DO_NOT_COPY_VALUES,&Bfd);
2655: MatColoringCreate(Bfd,&coloring);
2656: MatColoringSetType(coloring,MATCOLORINGSL);
2657: MatColoringSetFromOptions(coloring);
2658: MatColoringApply(coloring,&iscoloring);
2659: MatColoringDestroy(&coloring);
2660: MatFDColoringCreate(Bfd,iscoloring,&matfdcoloring);
2661: MatFDColoringSetFromOptions(matfdcoloring);
2662: MatFDColoringSetUp(Bfd,iscoloring,matfdcoloring);
2663: ISColoringDestroy(&iscoloring);
2665: /* This method of getting the function is currently unreliable since it doesn't work for DM local functions. */
2666: SNESGetFunction(snes,NULL,&func,&funcctx);
2667: MatFDColoringSetFunction(matfdcoloring,(PetscErrorCode (*)(void))func,funcctx);
2668: PetscObjectSetOptionsPrefix((PetscObject)matfdcoloring,((PetscObject)snes)->prefix);
2669: PetscObjectAppendOptionsPrefix((PetscObject)matfdcoloring,"coloring_");
2670: MatFDColoringSetFromOptions(matfdcoloring);
2671: MatFDColoringApply(Bfd,matfdcoloring,X,snes);
2672: MatFDColoringDestroy(&matfdcoloring);
2674: PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)snes),&vstdout);
2675: if (flag_draw || flag_contour) {
2676: PetscViewerDrawOpen(PetscObjectComm((PetscObject)snes),0,"Colored Jacobians",PETSC_DECIDE,PETSC_DECIDE,300,300,&vdraw);
2677: if (flag_contour) {PetscViewerPushFormat(vdraw,PETSC_VIEWER_DRAW_CONTOUR);}
2678: } else vdraw = NULL;
2679: PetscViewerASCIIPrintf(vstdout,"Explicit preconditioning Jacobian\n");
2680: if (flag_display) {MatView(B,vstdout);}
2681: if (vdraw) {MatView(B,vdraw);}
2682: PetscViewerASCIIPrintf(vstdout,"Colored Finite difference Jacobian\n");
2683: if (flag_display) {MatView(Bfd,vstdout);}
2684: if (vdraw) {MatView(Bfd,vdraw);}
2685: MatAYPX(Bfd,-1.0,B,SAME_NONZERO_PATTERN);
2686: MatNorm(Bfd,NORM_1,&norm1);
2687: MatNorm(Bfd,NORM_FROBENIUS,&norm2);
2688: MatNorm(Bfd,NORM_MAX,&normmax);
2689: PetscViewerASCIIPrintf(vstdout,"User-provided matrix minus finite difference Jacobian, norm1=%g normFrob=%g normmax=%g\n",(double)norm1,(double)norm2,(double)normmax);
2690: if (flag_display) {MatView(Bfd,vstdout);}
2691: if (vdraw) { /* Always use contour for the difference */
2692: PetscViewerPushFormat(vdraw,PETSC_VIEWER_DRAW_CONTOUR);
2693: MatView(Bfd,vdraw);
2694: PetscViewerPopFormat(vdraw);
2695: }
2696: if (flag_contour) {PetscViewerPopFormat(vdraw);}
2698: if (flag_threshold) {
2699: PetscInt bs,rstart,rend,i;
2700: MatGetBlockSize(B,&bs);
2701: MatGetOwnershipRange(B,&rstart,&rend);
2702: for (i=rstart; i<rend; i++) {
2703: const PetscScalar *ba,*ca;
2704: const PetscInt *bj,*cj;
2705: PetscInt bn,cn,j,maxentrycol = -1,maxdiffcol = -1,maxrdiffcol = -1;
2706: PetscReal maxentry = 0,maxdiff = 0,maxrdiff = 0;
2707: MatGetRow(B,i,&bn,&bj,&ba);
2708: MatGetRow(Bfd,i,&cn,&cj,&ca);
2709: if (bn != cn) SETERRQ(((PetscObject)A)->comm,PETSC_ERR_PLIB,"Unexpected different nonzero pattern in -snes_compare_coloring_threshold");
2710: for (j=0; j<bn; j++) {
2711: PetscReal rdiff = PetscAbsScalar(ca[j]) / (threshold_atol + threshold_rtol*PetscAbsScalar(ba[j]));
2712: if (PetscAbsScalar(ba[j]) > PetscAbs(maxentry)) {
2713: maxentrycol = bj[j];
2714: maxentry = PetscRealPart(ba[j]);
2715: }
2716: if (PetscAbsScalar(ca[j]) > PetscAbs(maxdiff)) {
2717: maxdiffcol = bj[j];
2718: maxdiff = PetscRealPart(ca[j]);
2719: }
2720: if (rdiff > maxrdiff) {
2721: maxrdiffcol = bj[j];
2722: maxrdiff = rdiff;
2723: }
2724: }
2725: if (maxrdiff > 1) {
2726: 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);
2727: for (j=0; j<bn; j++) {
2728: PetscReal rdiff;
2729: rdiff = PetscAbsScalar(ca[j]) / (threshold_atol + threshold_rtol*PetscAbsScalar(ba[j]));
2730: if (rdiff > 1) {
2731: PetscViewerASCIIPrintf(vstdout," (%D,%g:%g)",bj[j],(double)PetscRealPart(ba[j]),(double)PetscRealPart(ca[j]));
2732: }
2733: }
2734: PetscViewerASCIIPrintf(vstdout,"\n",i,maxentry,maxdiff,maxrdiff);
2735: }
2736: MatRestoreRow(B,i,&bn,&bj,&ba);
2737: MatRestoreRow(Bfd,i,&cn,&cj,&ca);
2738: }
2739: }
2740: PetscViewerDestroy(&vdraw);
2741: MatDestroy(&Bfd);
2742: }
2743: }
2744: return(0);
2745: }
2747: /*MC
2748: SNESJacobianFunction - Function used to convey the nonlinear Jacobian of the function to be solved by SNES
2750: Synopsis:
2751: #include "petscsnes.h"
2752: PetscErrorCode SNESJacobianFunction(SNES snes,Vec x,Mat Amat,Mat Pmat,void *ctx);
2754: + x - input vector
2755: . Amat - the matrix that defines the (approximate) Jacobian
2756: . Pmat - the matrix to be used in constructing the preconditioner, usually the same as Amat.
2757: - ctx - [optional] user-defined Jacobian context
2759: Level: intermediate
2761: .seealso: SNESSetFunction(), SNESGetFunction(), SNESSetJacobian(), SNESGetJacobian()
2762: M*/
2764: /*@C
2765: SNESSetJacobian - Sets the function to compute Jacobian as well as the
2766: location to store the matrix.
2768: Logically Collective on SNES and Mat
2770: Input Parameters:
2771: + snes - the SNES context
2772: . Amat - the matrix that defines the (approximate) Jacobian
2773: . Pmat - the matrix to be used in constructing the preconditioner, usually the same as Amat.
2774: . J - Jacobian evaluation routine (if NULL then SNES retains any previously set value), see SNESJacobianFunction for details
2775: - ctx - [optional] user-defined context for private data for the
2776: Jacobian evaluation routine (may be NULL) (if NULL then SNES retains any previously set value)
2778: Notes:
2779: If the Amat matrix and Pmat matrix are different you must call MatAssemblyBegin/End() on
2780: each matrix.
2782: If you know the operator Amat has a null space you can use MatSetNullSpace() and MatSetTransposeNullSpace() to supply the null
2783: space to Amat and the KSP solvers will automatically use that null space as needed during the solution process.
2785: If using SNESComputeJacobianDefaultColor() to assemble a Jacobian, the ctx argument
2786: must be a MatFDColoring.
2788: Other defect-correction schemes can be used by computing a different matrix in place of the Jacobian. One common
2789: example is to use the "Picard linearization" which only differentiates through the highest order parts of each term.
2791: Level: beginner
2793: .keywords: SNES, nonlinear, set, Jacobian, matrix
2795: .seealso: KSPSetOperators(), SNESSetFunction(), MatMFFDComputeJacobian(), SNESComputeJacobianDefaultColor(), MatStructure, J,
2796: SNESSetPicard(), SNESJacobianFunction
2797: @*/
2798: PetscErrorCode SNESSetJacobian(SNES snes,Mat Amat,Mat Pmat,PetscErrorCode (*J)(SNES,Vec,Mat,Mat,void*),void *ctx)
2799: {
2801: DM dm;
2809: SNESGetDM(snes,&dm);
2810: DMSNESSetJacobian(dm,J,ctx);
2811: if (Amat) {
2812: PetscObjectReference((PetscObject)Amat);
2813: MatDestroy(&snes->jacobian);
2815: snes->jacobian = Amat;
2816: }
2817: if (Pmat) {
2818: PetscObjectReference((PetscObject)Pmat);
2819: MatDestroy(&snes->jacobian_pre);
2821: snes->jacobian_pre = Pmat;
2822: }
2823: return(0);
2824: }
2826: /*@C
2827: SNESGetJacobian - Returns the Jacobian matrix and optionally the user
2828: provided context for evaluating the Jacobian.
2830: Not Collective, but Mat object will be parallel if SNES object is
2832: Input Parameter:
2833: . snes - the nonlinear solver context
2835: Output Parameters:
2836: + Amat - location to stash (approximate) Jacobian matrix (or NULL)
2837: . Pmat - location to stash matrix used to compute the preconditioner (or NULL)
2838: . J - location to put Jacobian function (or NULL), see SNESJacobianFunction for details on its calling sequence
2839: - ctx - location to stash Jacobian ctx (or NULL)
2841: Level: advanced
2843: .seealso: SNESSetJacobian(), SNESComputeJacobian(), SNESJacobianFunction, SNESGetFunction()
2844: @*/
2845: PetscErrorCode SNESGetJacobian(SNES snes,Mat *Amat,Mat *Pmat,PetscErrorCode (**J)(SNES,Vec,Mat,Mat,void*),void **ctx)
2846: {
2848: DM dm;
2849: DMSNES sdm;
2853: if (Amat) *Amat = snes->jacobian;
2854: if (Pmat) *Pmat = snes->jacobian_pre;
2855: SNESGetDM(snes,&dm);
2856: DMGetDMSNES(dm,&sdm);
2857: if (J) *J = sdm->ops->computejacobian;
2858: if (ctx) *ctx = sdm->jacobianctx;
2859: return(0);
2860: }
2862: /*@
2863: SNESSetUp - Sets up the internal data structures for the later use
2864: of a nonlinear solver.
2866: Collective on SNES
2868: Input Parameters:
2869: . snes - the SNES context
2871: Notes:
2872: For basic use of the SNES solvers the user need not explicitly call
2873: SNESSetUp(), since these actions will automatically occur during
2874: the call to SNESSolve(). However, if one wishes to control this
2875: phase separately, SNESSetUp() should be called after SNESCreate()
2876: and optional routines of the form SNESSetXXX(), but before SNESSolve().
2878: Level: advanced
2880: .keywords: SNES, nonlinear, setup
2882: .seealso: SNESCreate(), SNESSolve(), SNESDestroy()
2883: @*/
2884: PetscErrorCode SNESSetUp(SNES snes)
2885: {
2887: DM dm;
2888: DMSNES sdm;
2889: SNESLineSearch linesearch, pclinesearch;
2890: void *lsprectx,*lspostctx;
2891: PetscErrorCode (*precheck)(SNESLineSearch,Vec,Vec,PetscBool*,void*);
2892: PetscErrorCode (*postcheck)(SNESLineSearch,Vec,Vec,Vec,PetscBool*,PetscBool*,void*);
2893: PetscErrorCode (*func)(SNES,Vec,Vec,void*);
2894: Vec f,fpc;
2895: void *funcctx;
2896: PetscErrorCode (*jac)(SNES,Vec,Mat,Mat,void*);
2897: void *jacctx,*appctx;
2898: Mat j,jpre;
2902: if (snes->setupcalled) return(0);
2904: if (!((PetscObject)snes)->type_name) {
2905: SNESSetType(snes,SNESNEWTONLS);
2906: }
2908: SNESGetFunction(snes,&snes->vec_func,NULL,NULL);
2910: SNESGetDM(snes,&dm);
2911: DMGetDMSNES(dm,&sdm);
2912: if (!sdm->ops->computefunction) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_ARG_WRONGSTATE,"Function never provided to SNES object");
2913: if (!sdm->ops->computejacobian) {
2914: DMSNESSetJacobian(dm,SNESComputeJacobianDefaultColor,NULL);
2915: }
2916: if (!snes->vec_func) {
2917: DMCreateGlobalVector(dm,&snes->vec_func);
2918: }
2920: if (!snes->ksp) {
2921: SNESGetKSP(snes, &snes->ksp);
2922: }
2924: if (!snes->linesearch) {
2925: SNESGetLineSearch(snes, &snes->linesearch);
2926: }
2927: SNESLineSearchSetFunction(snes->linesearch,SNESComputeFunction);
2929: if (snes->npc && (snes->npcside== PC_LEFT)) {
2930: snes->mf = PETSC_TRUE;
2931: snes->mf_operator = PETSC_FALSE;
2932: }
2934: if (snes->npc) {
2935: /* copy the DM over */
2936: SNESGetDM(snes,&dm);
2937: SNESSetDM(snes->npc,dm);
2939: SNESGetFunction(snes,&f,&func,&funcctx);
2940: VecDuplicate(f,&fpc);
2941: SNESSetFunction(snes->npc,fpc,func,funcctx);
2942: SNESGetJacobian(snes,&j,&jpre,&jac,&jacctx);
2943: SNESSetJacobian(snes->npc,j,jpre,jac,jacctx);
2944: SNESGetApplicationContext(snes,&appctx);
2945: SNESSetApplicationContext(snes->npc,appctx);
2946: VecDestroy(&fpc);
2948: /* copy the function pointers over */
2949: PetscObjectCopyFortranFunctionPointers((PetscObject)snes,(PetscObject)snes->npc);
2951: /* default to 1 iteration */
2952: SNESSetTolerances(snes->npc,0.0,0.0,0.0,1,snes->npc->max_funcs);
2953: if (snes->npcside==PC_RIGHT) {
2954: SNESSetNormSchedule(snes->npc,SNES_NORM_FINAL_ONLY);
2955: } else {
2956: SNESSetNormSchedule(snes->npc,SNES_NORM_NONE);
2957: }
2958: SNESSetFromOptions(snes->npc);
2960: /* copy the line search context over */
2961: SNESGetLineSearch(snes,&linesearch);
2962: SNESGetLineSearch(snes->npc,&pclinesearch);
2963: SNESLineSearchGetPreCheck(linesearch,&precheck,&lsprectx);
2964: SNESLineSearchGetPostCheck(linesearch,&postcheck,&lspostctx);
2965: SNESLineSearchSetPreCheck(pclinesearch,precheck,lsprectx);
2966: SNESLineSearchSetPostCheck(pclinesearch,postcheck,lspostctx);
2967: PetscObjectCopyFortranFunctionPointers((PetscObject)linesearch, (PetscObject)pclinesearch);
2968: }
2969: if (snes->mf) {
2970: SNESSetUpMatrixFree_Private(snes, snes->mf_operator, snes->mf_version);
2971: }
2972: if (snes->ops->usercompute && !snes->user) {
2973: (*snes->ops->usercompute)(snes,(void**)&snes->user);
2974: }
2976: snes->jac_iter = 0;
2977: snes->pre_iter = 0;
2979: if (snes->ops->setup) {
2980: (*snes->ops->setup)(snes);
2981: }
2983: if (snes->npc && (snes->npcside== PC_LEFT)) {
2984: if (snes->functype == SNES_FUNCTION_PRECONDITIONED) {
2985: SNESGetLineSearch(snes,&linesearch);
2986: SNESLineSearchSetFunction(linesearch,SNESComputeFunctionDefaultNPC);
2987: }
2988: }
2990: snes->setupcalled = PETSC_TRUE;
2991: return(0);
2992: }
2994: /*@
2995: SNESReset - Resets a SNES context to the snessetupcalled = 0 state and removes any allocated Vecs and Mats
2997: Collective on SNES
2999: Input Parameter:
3000: . snes - iterative context obtained from SNESCreate()
3002: Level: intermediate
3004: Notes:
3005: Also calls the application context destroy routine set with SNESSetComputeApplicationContext()
3007: .keywords: SNES, destroy
3009: .seealso: SNESCreate(), SNESSetUp(), SNESSolve()
3010: @*/
3011: PetscErrorCode SNESReset(SNES snes)
3012: {
3017: if (snes->ops->userdestroy && snes->user) {
3018: (*snes->ops->userdestroy)((void**)&snes->user);
3019: snes->user = NULL;
3020: }
3021: if (snes->npc) {
3022: SNESReset(snes->npc);
3023: }
3025: if (snes->ops->reset) {
3026: (*snes->ops->reset)(snes);
3027: }
3028: if (snes->ksp) {
3029: KSPReset(snes->ksp);
3030: }
3032: if (snes->linesearch) {
3033: SNESLineSearchReset(snes->linesearch);
3034: }
3036: VecDestroy(&snes->vec_rhs);
3037: VecDestroy(&snes->vec_sol);
3038: VecDestroy(&snes->vec_sol_update);
3039: VecDestroy(&snes->vec_func);
3040: MatDestroy(&snes->jacobian);
3041: MatDestroy(&snes->jacobian_pre);
3042: VecDestroyVecs(snes->nwork,&snes->work);
3043: VecDestroyVecs(snes->nvwork,&snes->vwork);
3045: snes->alwayscomputesfinalresidual = PETSC_FALSE;
3047: snes->nwork = snes->nvwork = 0;
3048: snes->setupcalled = PETSC_FALSE;
3049: return(0);
3050: }
3052: /*@
3053: SNESDestroy - Destroys the nonlinear solver context that was created
3054: with SNESCreate().
3056: Collective on SNES
3058: Input Parameter:
3059: . snes - the SNES context
3061: Level: beginner
3063: .keywords: SNES, nonlinear, destroy
3065: .seealso: SNESCreate(), SNESSolve()
3066: @*/
3067: PetscErrorCode SNESDestroy(SNES *snes)
3068: {
3072: if (!*snes) return(0);
3074: if (--((PetscObject)(*snes))->refct > 0) {*snes = 0; return(0);}
3076: SNESReset((*snes));
3077: SNESDestroy(&(*snes)->npc);
3079: /* if memory was published with SAWs then destroy it */
3080: PetscObjectSAWsViewOff((PetscObject)*snes);
3081: if ((*snes)->ops->destroy) {(*((*snes))->ops->destroy)((*snes));}
3083: if ((*snes)->dm) {DMCoarsenHookRemove((*snes)->dm,DMCoarsenHook_SNESVecSol,DMRestrictHook_SNESVecSol,*snes);}
3084: DMDestroy(&(*snes)->dm);
3085: KSPDestroy(&(*snes)->ksp);
3086: SNESLineSearchDestroy(&(*snes)->linesearch);
3088: PetscFree((*snes)->kspconvctx);
3089: if ((*snes)->ops->convergeddestroy) {
3090: (*(*snes)->ops->convergeddestroy)((*snes)->cnvP);
3091: }
3092: if ((*snes)->conv_malloc) {
3093: PetscFree((*snes)->conv_hist);
3094: PetscFree((*snes)->conv_hist_its);
3095: }
3096: SNESMonitorCancel((*snes));
3097: PetscHeaderDestroy(snes);
3098: return(0);
3099: }
3101: /* ----------- Routines to set solver parameters ---------- */
3103: /*@
3104: SNESSetLagPreconditioner - Determines when the preconditioner is rebuilt in the nonlinear solve.
3106: Logically Collective on SNES
3108: Input Parameters:
3109: + snes - the SNES context
3110: - lag - -1 indicates NEVER rebuild, 1 means rebuild every time the Jacobian is computed within a single nonlinear solve, 2 means every second time
3111: the Jacobian is built etc. -2 indicates rebuild preconditioner at next chance but then never rebuild after that
3113: Options Database Keys:
3114: . -snes_lag_preconditioner <lag>
3116: Notes:
3117: The default is 1
3118: The preconditioner is ALWAYS built in the first iteration of a nonlinear solve unless lag is -1
3119: If -1 is used before the very first nonlinear solve the preconditioner is still built because there is no previous preconditioner to use
3121: Level: intermediate
3123: .keywords: SNES, nonlinear, set, convergence, tolerances
3125: .seealso: SNESSetTrustRegionTolerance(), SNESGetLagPreconditioner(), SNESSetLagJacobian(), SNESGetLagJacobian()
3127: @*/
3128: PetscErrorCode SNESSetLagPreconditioner(SNES snes,PetscInt lag)
3129: {
3132: if (lag < -2) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Lag must be -2, -1, 1 or greater");
3133: if (!lag) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Lag cannot be 0");
3135: snes->lagpreconditioner = lag;
3136: return(0);
3137: }
3139: /*@
3140: SNESSetGridSequence - sets the number of steps of grid sequencing that SNES does
3142: Logically Collective on SNES
3144: Input Parameters:
3145: + snes - the SNES context
3146: - steps - the number of refinements to do, defaults to 0
3148: Options Database Keys:
3149: . -snes_grid_sequence <steps>
3151: Level: intermediate
3153: Notes:
3154: Use SNESGetSolution() to extract the fine grid solution after grid sequencing.
3156: .keywords: SNES, nonlinear, set, convergence, tolerances
3158: .seealso: SNESSetTrustRegionTolerance(), SNESGetLagPreconditioner(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESGetGridSequence()
3160: @*/
3161: PetscErrorCode SNESSetGridSequence(SNES snes,PetscInt steps)
3162: {
3166: snes->gridsequence = steps;
3167: return(0);
3168: }
3170: /*@
3171: SNESGetGridSequence - gets the number of steps of grid sequencing that SNES does
3173: Logically Collective on SNES
3175: Input Parameter:
3176: . snes - the SNES context
3178: Output Parameter:
3179: . steps - the number of refinements to do, defaults to 0
3181: Options Database Keys:
3182: . -snes_grid_sequence <steps>
3184: Level: intermediate
3186: Notes:
3187: Use SNESGetSolution() to extract the fine grid solution after grid sequencing.
3189: .keywords: SNES, nonlinear, set, convergence, tolerances
3191: .seealso: SNESSetTrustRegionTolerance(), SNESGetLagPreconditioner(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESSetGridSequence()
3193: @*/
3194: PetscErrorCode SNESGetGridSequence(SNES snes,PetscInt *steps)
3195: {
3198: *steps = snes->gridsequence;
3199: return(0);
3200: }
3202: /*@
3203: SNESGetLagPreconditioner - Indicates how often the preconditioner is rebuilt
3205: Not Collective
3207: Input Parameter:
3208: . snes - the SNES context
3210: Output Parameter:
3211: . lag - -1 indicates NEVER rebuild, 1 means rebuild every time the Jacobian is computed within a single nonlinear solve, 2 means every second time
3212: the Jacobian is built etc. -2 indicates rebuild preconditioner at next chance but then never rebuild after that
3214: Options Database Keys:
3215: . -snes_lag_preconditioner <lag>
3217: Notes:
3218: The default is 1
3219: The preconditioner is ALWAYS built in the first iteration of a nonlinear solve unless lag is -1
3221: Level: intermediate
3223: .keywords: SNES, nonlinear, set, convergence, tolerances
3225: .seealso: SNESSetTrustRegionTolerance(), SNESSetLagPreconditioner()
3227: @*/
3228: PetscErrorCode SNESGetLagPreconditioner(SNES snes,PetscInt *lag)
3229: {
3232: *lag = snes->lagpreconditioner;
3233: return(0);
3234: }
3236: /*@
3237: SNESSetLagJacobian - Determines when the Jacobian is rebuilt in the nonlinear solve. See SNESSetLagPreconditioner() for determining how
3238: often the preconditioner is rebuilt.
3240: Logically Collective on SNES
3242: Input Parameters:
3243: + snes - the SNES context
3244: - lag - -1 indicates NEVER rebuild, 1 means rebuild every time the Jacobian is computed within a single nonlinear solve, 2 means every second time
3245: the Jacobian is built etc. -2 means rebuild at next chance but then never again
3247: Options Database Keys:
3248: . -snes_lag_jacobian <lag>
3250: Notes:
3251: The default is 1
3252: The Jacobian is ALWAYS built in the first iteration of a nonlinear solve unless lag is -1
3253: 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
3254: at the next Newton step but never again (unless it is reset to another value)
3256: Level: intermediate
3258: .keywords: SNES, nonlinear, set, convergence, tolerances
3260: .seealso: SNESSetTrustRegionTolerance(), SNESGetLagPreconditioner(), SNESSetLagPreconditioner(), SNESGetLagJacobian()
3262: @*/
3263: PetscErrorCode SNESSetLagJacobian(SNES snes,PetscInt lag)
3264: {
3267: if (lag < -2) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Lag must be -2, -1, 1 or greater");
3268: if (!lag) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Lag cannot be 0");
3270: snes->lagjacobian = lag;
3271: return(0);
3272: }
3274: /*@
3275: SNESGetLagJacobian - Indicates how often the Jacobian is rebuilt. See SNESGetLagPreconditioner() to determine when the preconditioner is rebuilt
3277: Not Collective
3279: Input Parameter:
3280: . snes - the SNES context
3282: Output Parameter:
3283: . lag - -1 indicates NEVER rebuild, 1 means rebuild every time the Jacobian is computed within a single nonlinear solve, 2 means every second time
3284: the Jacobian is built etc.
3286: Options Database Keys:
3287: . -snes_lag_jacobian <lag>
3289: Notes:
3290: The default is 1
3291: The jacobian is ALWAYS built in the first iteration of a nonlinear solve unless lag is -1
3293: Level: intermediate
3295: .keywords: SNES, nonlinear, set, convergence, tolerances
3297: .seealso: SNESSetTrustRegionTolerance(), SNESSetLagJacobian(), SNESSetLagPreconditioner(), SNESGetLagPreconditioner()
3299: @*/
3300: PetscErrorCode SNESGetLagJacobian(SNES snes,PetscInt *lag)
3301: {
3304: *lag = snes->lagjacobian;
3305: return(0);
3306: }
3308: /*@
3309: SNESSetLagJacobianPersists - Set whether or not the Jacobian lagging persists through multiple solves
3311: Logically collective on SNES
3313: Input Parameter:
3314: + snes - the SNES context
3315: - flg - jacobian lagging persists if true
3317: Options Database Keys:
3318: . -snes_lag_jacobian_persists <flg>
3320: Notes:
3321: This is useful both for nonlinear preconditioning, where it's appropriate to have the Jacobian be stale by
3322: several solves, and for implicit time-stepping, where Jacobian lagging in the inner nonlinear solve over several
3323: timesteps may present huge efficiency gains.
3325: Level: developer
3327: .keywords: SNES, nonlinear, lag
3329: .seealso: SNESSetLagPreconditionerPersists(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESGetNPC()
3331: @*/
3332: PetscErrorCode SNESSetLagJacobianPersists(SNES snes,PetscBool flg)
3333: {
3337: snes->lagjac_persist = flg;
3338: return(0);
3339: }
3341: /*@
3342: SNESSetLagPreconditionerPersists - Set whether or not the preconditioner lagging persists through multiple solves
3344: Logically Collective on SNES
3346: Input Parameter:
3347: + snes - the SNES context
3348: - flg - preconditioner lagging persists if true
3350: Options Database Keys:
3351: . -snes_lag_jacobian_persists <flg>
3353: Notes:
3354: This is useful both for nonlinear preconditioning, where it's appropriate to have the preconditioner be stale
3355: by several solves, and for implicit time-stepping, where preconditioner lagging in the inner nonlinear solve over
3356: several timesteps may present huge efficiency gains.
3358: Level: developer
3360: .keywords: SNES, nonlinear, lag
3362: .seealso: SNESSetLagJacobianPersists(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESGetNPC()
3364: @*/
3365: PetscErrorCode SNESSetLagPreconditionerPersists(SNES snes,PetscBool flg)
3366: {
3370: snes->lagpre_persist = flg;
3371: return(0);
3372: }
3374: /*@
3375: SNESSetForceIteration - force SNESSolve() to take at least one iteration regardless of the initial residual norm
3377: Logically Collective on SNES
3379: Input Parameters:
3380: + snes - the SNES context
3381: - force - PETSC_TRUE require at least one iteration
3383: Options Database Keys:
3384: . -snes_force_iteration <force> - Sets forcing an iteration
3386: Notes:
3387: This is used sometimes with TS to prevent TS from detecting a false steady state solution
3389: Level: intermediate
3391: .keywords: SNES, nonlinear, set, convergence, tolerances
3393: .seealso: SNESSetTrustRegionTolerance(), SNESSetDivergenceTolerance()
3394: @*/
3395: PetscErrorCode SNESSetForceIteration(SNES snes,PetscBool force)
3396: {
3399: snes->forceiteration = force;
3400: return(0);
3401: }
3403: /*@
3404: SNESGetForceIteration - Whether or not to force SNESSolve() take at least one iteration regardless of the initial residual norm
3406: Logically Collective on SNES
3408: Input Parameters:
3409: . snes - the SNES context
3411: Output Parameter:
3412: . force - PETSC_TRUE requires at least one iteration.
3414: .keywords: SNES, nonlinear, set, convergence, tolerances
3416: Level: intermediate
3418: .seealso: SNESSetForceIteration(), SNESSetTrustRegionTolerance(), SNESSetDivergenceTolerance()
3419: @*/
3420: PetscErrorCode SNESGetForceIteration(SNES snes,PetscBool *force)
3421: {
3424: *force = snes->forceiteration;
3425: return(0);
3426: }
3428: /*@
3429: SNESSetTolerances - Sets various parameters used in convergence tests.
3431: Logically Collective on SNES
3433: Input Parameters:
3434: + snes - the SNES context
3435: . abstol - absolute convergence tolerance
3436: . rtol - relative convergence tolerance
3437: . stol - convergence tolerance in terms of the norm of the change in the solution between steps, || delta x || < stol*|| x ||
3438: . maxit - maximum number of iterations
3439: - maxf - maximum number of function evaluations (-1 indicates no limit)
3441: Options Database Keys:
3442: + -snes_atol <abstol> - Sets abstol
3443: . -snes_rtol <rtol> - Sets rtol
3444: . -snes_stol <stol> - Sets stol
3445: . -snes_max_it <maxit> - Sets maxit
3446: - -snes_max_funcs <maxf> - Sets maxf
3448: Notes:
3449: The default maximum number of iterations is 50.
3450: The default maximum number of function evaluations is 1000.
3452: Level: intermediate
3454: .keywords: SNES, nonlinear, set, convergence, tolerances
3456: .seealso: SNESSetTrustRegionTolerance(), SNESSetDivergenceTolerance(), SNESSetForceIteration()
3457: @*/
3458: PetscErrorCode SNESSetTolerances(SNES snes,PetscReal abstol,PetscReal rtol,PetscReal stol,PetscInt maxit,PetscInt maxf)
3459: {
3468: if (abstol != PETSC_DEFAULT) {
3469: if (abstol < 0.0) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Absolute tolerance %g must be non-negative",(double)abstol);
3470: snes->abstol = abstol;
3471: }
3472: if (rtol != PETSC_DEFAULT) {
3473: 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);
3474: snes->rtol = rtol;
3475: }
3476: if (stol != PETSC_DEFAULT) {
3477: if (stol < 0.0) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Step tolerance %g must be non-negative",(double)stol);
3478: snes->stol = stol;
3479: }
3480: if (maxit != PETSC_DEFAULT) {
3481: if (maxit < 0) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Maximum number of iterations %D must be non-negative",maxit);
3482: snes->max_its = maxit;
3483: }
3484: if (maxf != PETSC_DEFAULT) {
3485: if (maxf < -1) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Maximum number of function evaluations %D must be -1 or nonnegative",maxf);
3486: snes->max_funcs = maxf;
3487: }
3488: snes->tolerancesset = PETSC_TRUE;
3489: return(0);
3490: }
3492: /*@
3493: SNESSetDivergenceTolerance - Sets the divergence tolerance used for the SNES divergence test.
3495: Logically Collective on SNES
3497: Input Parameters:
3498: + snes - the SNES context
3499: - divtol - the divergence tolerance. Use -1 to deactivate the test.
3501: Options Database Keys:
3502: + -snes_divergence_tolerance <divtol> - Sets divtol
3504: Notes:
3505: The default divergence tolerance is 1e4.
3507: Level: intermediate
3509: .keywords: SNES, nonlinear, set, divergence, tolerance
3511: .seealso: SNESSetTolerances(), SNESGetDivergenceTolerance
3512: @*/
3513: PetscErrorCode SNESSetDivergenceTolerance(SNES snes,PetscReal divtol)
3514: {
3519: if (divtol != PETSC_DEFAULT) {
3520: snes->divtol = divtol;
3521: }
3522: else {
3523: snes->divtol = 1.0e4;
3524: }
3525: return(0);
3526: }
3528: /*@
3529: SNESGetTolerances - Gets various parameters used in convergence tests.
3531: Not Collective
3533: Input Parameters:
3534: + snes - the SNES context
3535: . atol - absolute convergence tolerance
3536: . rtol - relative convergence tolerance
3537: . stol - convergence tolerance in terms of the norm
3538: of the change in the solution between steps
3539: . maxit - maximum number of iterations
3540: - maxf - maximum number of function evaluations
3542: Notes:
3543: The user can specify NULL for any parameter that is not needed.
3545: Level: intermediate
3547: .keywords: SNES, nonlinear, get, convergence, tolerances
3549: .seealso: SNESSetTolerances()
3550: @*/
3551: PetscErrorCode SNESGetTolerances(SNES snes,PetscReal *atol,PetscReal *rtol,PetscReal *stol,PetscInt *maxit,PetscInt *maxf)
3552: {
3555: if (atol) *atol = snes->abstol;
3556: if (rtol) *rtol = snes->rtol;
3557: if (stol) *stol = snes->stol;
3558: if (maxit) *maxit = snes->max_its;
3559: if (maxf) *maxf = snes->max_funcs;
3560: return(0);
3561: }
3563: /*@
3564: SNESGetDivergenceTolerance - Gets divergence tolerance used in divergence test.
3566: Not Collective
3568: Input Parameters:
3569: + snes - the SNES context
3570: - divtol - divergence tolerance
3572: Level: intermediate
3574: .keywords: SNES, nonlinear, get, divergence, tolerance
3576: .seealso: SNESSetDivergenceTolerance()
3577: @*/
3578: PetscErrorCode SNESGetDivergenceTolerance(SNES snes,PetscReal *divtol)
3579: {
3582: if (divtol) *divtol = snes->divtol;
3583: return(0);
3584: }
3586: /*@
3587: SNESSetTrustRegionTolerance - Sets the trust region parameter tolerance.
3589: Logically Collective on SNES
3591: Input Parameters:
3592: + snes - the SNES context
3593: - tol - tolerance
3595: Options Database Key:
3596: . -snes_trtol <tol> - Sets tol
3598: Level: intermediate
3600: .keywords: SNES, nonlinear, set, trust region, tolerance
3602: .seealso: SNESSetTolerances()
3603: @*/
3604: PetscErrorCode SNESSetTrustRegionTolerance(SNES snes,PetscReal tol)
3605: {
3609: snes->deltatol = tol;
3610: return(0);
3611: }
3613: /*
3614: Duplicate the lg monitors for SNES from KSP; for some reason with
3615: dynamic libraries things don't work under Sun4 if we just use
3616: macros instead of functions
3617: */
3618: PetscErrorCode SNESMonitorLGResidualNorm(SNES snes,PetscInt it,PetscReal norm,void *ctx)
3619: {
3624: KSPMonitorLGResidualNorm((KSP)snes,it,norm,ctx);
3625: return(0);
3626: }
3628: PetscErrorCode SNESMonitorLGCreate(MPI_Comm comm,const char host[],const char label[],int x,int y,int m,int n,PetscDrawLG *lgctx)
3629: {
3633: KSPMonitorLGResidualNormCreate(comm,host,label,x,y,m,n,lgctx);
3634: return(0);
3635: }
3637: PETSC_INTERN PetscErrorCode SNESMonitorRange_Private(SNES,PetscInt,PetscReal*);
3639: PetscErrorCode SNESMonitorLGRange(SNES snes,PetscInt n,PetscReal rnorm,void *monctx)
3640: {
3641: PetscDrawLG lg;
3642: PetscErrorCode ierr;
3643: PetscReal x,y,per;
3644: PetscViewer v = (PetscViewer)monctx;
3645: static PetscReal prev; /* should be in the context */
3646: PetscDraw draw;
3650: PetscViewerDrawGetDrawLG(v,0,&lg);
3651: if (!n) {PetscDrawLGReset(lg);}
3652: PetscDrawLGGetDraw(lg,&draw);
3653: PetscDrawSetTitle(draw,"Residual norm");
3654: x = (PetscReal)n;
3655: if (rnorm > 0.0) y = PetscLog10Real(rnorm);
3656: else y = -15.0;
3657: PetscDrawLGAddPoint(lg,&x,&y);
3658: if (n < 20 || !(n % 5) || snes->reason) {
3659: PetscDrawLGDraw(lg);
3660: PetscDrawLGSave(lg);
3661: }
3663: PetscViewerDrawGetDrawLG(v,1,&lg);
3664: if (!n) {PetscDrawLGReset(lg);}
3665: PetscDrawLGGetDraw(lg,&draw);
3666: PetscDrawSetTitle(draw,"% elemts > .2*max elemt");
3667: SNESMonitorRange_Private(snes,n,&per);
3668: x = (PetscReal)n;
3669: y = 100.0*per;
3670: PetscDrawLGAddPoint(lg,&x,&y);
3671: if (n < 20 || !(n % 5) || snes->reason) {
3672: PetscDrawLGDraw(lg);
3673: PetscDrawLGSave(lg);
3674: }
3676: PetscViewerDrawGetDrawLG(v,2,&lg);
3677: if (!n) {prev = rnorm;PetscDrawLGReset(lg);}
3678: PetscDrawLGGetDraw(lg,&draw);
3679: PetscDrawSetTitle(draw,"(norm -oldnorm)/oldnorm");
3680: x = (PetscReal)n;
3681: y = (prev - rnorm)/prev;
3682: PetscDrawLGAddPoint(lg,&x,&y);
3683: if (n < 20 || !(n % 5) || snes->reason) {
3684: PetscDrawLGDraw(lg);
3685: PetscDrawLGSave(lg);
3686: }
3688: PetscViewerDrawGetDrawLG(v,3,&lg);
3689: if (!n) {PetscDrawLGReset(lg);}
3690: PetscDrawLGGetDraw(lg,&draw);
3691: PetscDrawSetTitle(draw,"(norm -oldnorm)/oldnorm*(% > .2 max)");
3692: x = (PetscReal)n;
3693: y = (prev - rnorm)/(prev*per);
3694: if (n > 2) { /*skip initial crazy value */
3695: PetscDrawLGAddPoint(lg,&x,&y);
3696: }
3697: if (n < 20 || !(n % 5) || snes->reason) {
3698: PetscDrawLGDraw(lg);
3699: PetscDrawLGSave(lg);
3700: }
3701: prev = rnorm;
3702: return(0);
3703: }
3705: /*@
3706: SNESMonitor - runs the user provided monitor routines, if they exist
3708: Collective on SNES
3710: Input Parameters:
3711: + snes - nonlinear solver context obtained from SNESCreate()
3712: . iter - iteration number
3713: - rnorm - relative norm of the residual
3715: Notes:
3716: This routine is called by the SNES implementations.
3717: It does not typically need to be called by the user.
3719: Level: developer
3721: .seealso: SNESMonitorSet()
3722: @*/
3723: PetscErrorCode SNESMonitor(SNES snes,PetscInt iter,PetscReal rnorm)
3724: {
3726: PetscInt i,n = snes->numbermonitors;
3729: VecLockPush(snes->vec_sol);
3730: for (i=0; i<n; i++) {
3731: (*snes->monitor[i])(snes,iter,rnorm,snes->monitorcontext[i]);
3732: }
3733: VecLockPop(snes->vec_sol);
3734: return(0);
3735: }
3737: /* ------------ Routines to set performance monitoring options ----------- */
3739: /*MC
3740: SNESMonitorFunction - functional form passed to SNESMonitorSet() to monitor convergence of nonlinear solver
3742: Synopsis:
3743: #include <petscsnes.h>
3744: $ PetscErrorCode SNESMonitorFunction(SNES snes,PetscInt its, PetscReal norm,void *mctx)
3746: + snes - the SNES context
3747: . its - iteration number
3748: . norm - 2-norm function value (may be estimated)
3749: - mctx - [optional] monitoring context
3751: Level: advanced
3753: .seealso: SNESMonitorSet(), SNESMonitorGet()
3754: M*/
3756: /*@C
3757: SNESMonitorSet - Sets an ADDITIONAL function that is to be used at every
3758: iteration of the nonlinear solver to display the iteration's
3759: progress.
3761: Logically Collective on SNES
3763: Input Parameters:
3764: + snes - the SNES context
3765: . f - the monitor function, see SNESMonitorFunction for the calling sequence
3766: . mctx - [optional] user-defined context for private data for the
3767: monitor routine (use NULL if no context is desired)
3768: - monitordestroy - [optional] routine that frees monitor context
3769: (may be NULL)
3771: Options Database Keys:
3772: + -snes_monitor - sets SNESMonitorDefault()
3773: . -snes_monitor_lg_residualnorm - sets line graph monitor,
3774: uses SNESMonitorLGCreate()
3775: - -snes_monitor_cancel - cancels all monitors that have
3776: been hardwired into a code by
3777: calls to SNESMonitorSet(), but
3778: does not cancel those set via
3779: the options database.
3781: Notes:
3782: Several different monitoring routines may be set by calling
3783: SNESMonitorSet() multiple times; all will be called in the
3784: order in which they were set.
3786: Fortran Notes:
3787: Only a single monitor function can be set for each SNES object
3789: Level: intermediate
3791: .keywords: SNES, nonlinear, set, monitor
3793: .seealso: SNESMonitorDefault(), SNESMonitorCancel(), SNESMonitorFunction
3794: @*/
3795: PetscErrorCode SNESMonitorSet(SNES snes,PetscErrorCode (*f)(SNES,PetscInt,PetscReal,void*),void *mctx,PetscErrorCode (*monitordestroy)(void**))
3796: {
3797: PetscInt i;
3799: PetscBool identical;
3803: for (i=0; i<snes->numbermonitors;i++) {
3804: PetscMonitorCompare((PetscErrorCode (*)(void))f,mctx,monitordestroy,(PetscErrorCode (*)(void))snes->monitor[i],snes->monitorcontext[i],snes->monitordestroy[i],&identical);
3805: if (identical) return(0);
3806: }
3807: if (snes->numbermonitors >= MAXSNESMONITORS) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Too many monitors set");
3808: snes->monitor[snes->numbermonitors] = f;
3809: snes->monitordestroy[snes->numbermonitors] = monitordestroy;
3810: snes->monitorcontext[snes->numbermonitors++] = (void*)mctx;
3811: return(0);
3812: }
3814: /*@
3815: SNESMonitorCancel - Clears all the monitor functions for a SNES object.
3817: Logically Collective on SNES
3819: Input Parameters:
3820: . snes - the SNES context
3822: Options Database Key:
3823: . -snes_monitor_cancel - cancels all monitors that have been hardwired
3824: into a code by calls to SNESMonitorSet(), but does not cancel those
3825: set via the options database
3827: Notes:
3828: There is no way to clear one specific monitor from a SNES object.
3830: Level: intermediate
3832: .keywords: SNES, nonlinear, set, monitor
3834: .seealso: SNESMonitorDefault(), SNESMonitorSet()
3835: @*/
3836: PetscErrorCode SNESMonitorCancel(SNES snes)
3837: {
3839: PetscInt i;
3843: for (i=0; i<snes->numbermonitors; i++) {
3844: if (snes->monitordestroy[i]) {
3845: (*snes->monitordestroy[i])(&snes->monitorcontext[i]);
3846: }
3847: }
3848: snes->numbermonitors = 0;
3849: return(0);
3850: }
3852: /*MC
3853: SNESConvergenceTestFunction - functional form used for testing of convergence of nonlinear solver
3855: Synopsis:
3856: #include <petscsnes.h>
3857: $ PetscErrorCode SNESConvergenceTest(SNES snes,PetscInt it,PetscReal xnorm,PetscReal gnorm,PetscReal f,SNESConvergedReason *reason,void *cctx)
3859: + snes - the SNES context
3860: . it - current iteration (0 is the first and is before any Newton step)
3861: . cctx - [optional] convergence context
3862: . reason - reason for convergence/divergence
3863: . xnorm - 2-norm of current iterate
3864: . gnorm - 2-norm of current step
3865: - f - 2-norm of function
3867: Level: intermediate
3869: .seealso: SNESSetConvergenceTest(), SNESGetConvergenceTest()
3870: M*/
3872: /*@C
3873: SNESSetConvergenceTest - Sets the function that is to be used
3874: to test for convergence of the nonlinear iterative solution.
3876: Logically Collective on SNES
3878: Input Parameters:
3879: + snes - the SNES context
3880: . SNESConvergenceTestFunction - routine to test for convergence
3881: . cctx - [optional] context for private data for the convergence routine (may be NULL)
3882: - destroy - [optional] destructor for the context (may be NULL; NULL_FUNCTION in Fortran)
3884: Level: advanced
3886: .keywords: SNES, nonlinear, set, convergence, test
3888: .seealso: SNESConvergedDefault(), SNESConvergedSkip(), SNESConvergenceTestFunction
3889: @*/
3890: PetscErrorCode SNESSetConvergenceTest(SNES snes,PetscErrorCode (*SNESConvergenceTestFunction)(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*),void *cctx,PetscErrorCode (*destroy)(void*))
3891: {
3896: if (!SNESConvergenceTestFunction) SNESConvergenceTestFunction = SNESConvergedSkip;
3897: if (snes->ops->convergeddestroy) {
3898: (*snes->ops->convergeddestroy)(snes->cnvP);
3899: }
3900: snes->ops->converged = SNESConvergenceTestFunction;
3901: snes->ops->convergeddestroy = destroy;
3902: snes->cnvP = cctx;
3903: return(0);
3904: }
3906: /*@
3907: SNESGetConvergedReason - Gets the reason the SNES iteration was stopped.
3909: Not Collective
3911: Input Parameter:
3912: . snes - the SNES context
3914: Output Parameter:
3915: . reason - negative value indicates diverged, positive value converged, see SNESConvergedReason or the
3916: manual pages for the individual convergence tests for complete lists
3918: Options Database:
3919: . -snes_converged_reason - prints the reason to standard out
3921: Level: intermediate
3923: Notes:
3924: Should only be called after the call the SNESSolve() is complete, if it is called earlier it returns the value SNES__CONVERGED_ITERATING.
3926: .keywords: SNES, nonlinear, set, convergence, test
3928: .seealso: SNESSetConvergenceTest(), SNESSetConvergedReason(), SNESConvergedReason
3929: @*/
3930: PetscErrorCode SNESGetConvergedReason(SNES snes,SNESConvergedReason *reason)
3931: {
3935: *reason = snes->reason;
3936: return(0);
3937: }
3939: /*@
3940: SNESSetConvergedReason - Sets the reason the SNES iteration was stopped.
3942: Not Collective
3944: Input Parameters:
3945: + snes - the SNES context
3946: - reason - negative value indicates diverged, positive value converged, see SNESConvergedReason or the
3947: manual pages for the individual convergence tests for complete lists
3949: Level: intermediate
3951: .keywords: SNES, nonlinear, set, convergence, test
3952: .seealso: SNESGetConvergedReason(), SNESSetConvergenceTest(), SNESConvergedReason
3953: @*/
3954: PetscErrorCode SNESSetConvergedReason(SNES snes,SNESConvergedReason reason)
3955: {
3958: snes->reason = reason;
3959: return(0);
3960: }
3962: /*@
3963: SNESSetConvergenceHistory - Sets the array used to hold the convergence history.
3965: Logically Collective on SNES
3967: Input Parameters:
3968: + snes - iterative context obtained from SNESCreate()
3969: . a - array to hold history, this array will contain the function norms computed at each step
3970: . its - integer array holds the number of linear iterations for each solve.
3971: . na - size of a and its
3972: - reset - PETSC_TRUE indicates each new nonlinear solve resets the history counter to zero,
3973: else it continues storing new values for new nonlinear solves after the old ones
3975: Notes:
3976: If 'a' and 'its' are NULL then space is allocated for the history. If 'na' PETSC_DECIDE or PETSC_DEFAULT then a
3977: default array of length 10000 is allocated.
3979: This routine is useful, e.g., when running a code for purposes
3980: of accurate performance monitoring, when no I/O should be done
3981: during the section of code that is being timed.
3983: Level: intermediate
3985: .keywords: SNES, set, convergence, history
3987: .seealso: SNESGetConvergenceHistory()
3989: @*/
3990: PetscErrorCode SNESSetConvergenceHistory(SNES snes,PetscReal a[],PetscInt its[],PetscInt na,PetscBool reset)
3991: {
3998: if (!a) {
3999: if (na == PETSC_DECIDE || na == PETSC_DEFAULT) na = 1000;
4000: PetscCalloc1(na,&a);
4001: PetscCalloc1(na,&its);
4003: snes->conv_malloc = PETSC_TRUE;
4004: }
4005: snes->conv_hist = a;
4006: snes->conv_hist_its = its;
4007: snes->conv_hist_max = na;
4008: snes->conv_hist_len = 0;
4009: snes->conv_hist_reset = reset;
4010: return(0);
4011: }
4013: #if defined(PETSC_HAVE_MATLAB_ENGINE)
4014: #include <engine.h> /* MATLAB include file */
4015: #include <mex.h> /* MATLAB include file */
4017: PETSC_EXTERN mxArray *SNESGetConvergenceHistoryMatlab(SNES snes)
4018: {
4019: mxArray *mat;
4020: PetscInt i;
4021: PetscReal *ar;
4024: mat = mxCreateDoubleMatrix(snes->conv_hist_len,1,mxREAL);
4025: ar = (PetscReal*) mxGetData(mat);
4026: for (i=0; i<snes->conv_hist_len; i++) ar[i] = snes->conv_hist[i];
4027: PetscFunctionReturn(mat);
4028: }
4029: #endif
4031: /*@C
4032: SNESGetConvergenceHistory - Gets the array used to hold the convergence history.
4034: Not Collective
4036: Input Parameter:
4037: . snes - iterative context obtained from SNESCreate()
4039: Output Parameters:
4040: . a - array to hold history
4041: . its - integer array holds the number of linear iterations (or
4042: negative if not converged) for each solve.
4043: - na - size of a and its
4045: Notes:
4046: The calling sequence for this routine in Fortran is
4047: $ call SNESGetConvergenceHistory(SNES snes, integer na, integer ierr)
4049: This routine is useful, e.g., when running a code for purposes
4050: of accurate performance monitoring, when no I/O should be done
4051: during the section of code that is being timed.
4053: Level: intermediate
4055: .keywords: SNES, get, convergence, history
4057: .seealso: SNESSetConvergencHistory()
4059: @*/
4060: PetscErrorCode SNESGetConvergenceHistory(SNES snes,PetscReal *a[],PetscInt *its[],PetscInt *na)
4061: {
4064: if (a) *a = snes->conv_hist;
4065: if (its) *its = snes->conv_hist_its;
4066: if (na) *na = snes->conv_hist_len;
4067: return(0);
4068: }
4070: /*@C
4071: SNESSetUpdate - Sets the general-purpose update function called
4072: at the beginning of every iteration of the nonlinear solve. Specifically
4073: it is called just before the Jacobian is "evaluated".
4075: Logically Collective on SNES
4077: Input Parameters:
4078: . snes - The nonlinear solver context
4079: . func - The function
4081: Calling sequence of func:
4082: . func (SNES snes, PetscInt step);
4084: . step - The current step of the iteration
4086: Level: advanced
4088: 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()
4089: This is not used by most users.
4091: .keywords: SNES, update
4093: .seealso SNESSetJacobian(), SNESSolve()
4094: @*/
4095: PetscErrorCode SNESSetUpdate(SNES snes, PetscErrorCode (*func)(SNES, PetscInt))
4096: {
4099: snes->ops->update = func;
4100: return(0);
4101: }
4103: /*
4104: SNESScaleStep_Private - Scales a step so that its length is less than the
4105: positive parameter delta.
4107: Input Parameters:
4108: + snes - the SNES context
4109: . y - approximate solution of linear system
4110: . fnorm - 2-norm of current function
4111: - delta - trust region size
4113: Output Parameters:
4114: + gpnorm - predicted function norm at the new point, assuming local
4115: linearization. The value is zero if the step lies within the trust
4116: region, and exceeds zero otherwise.
4117: - ynorm - 2-norm of the step
4119: Note:
4120: For non-trust region methods such as SNESNEWTONLS, the parameter delta
4121: is set to be the maximum allowable step size.
4123: .keywords: SNES, nonlinear, scale, step
4124: */
4125: PetscErrorCode SNESScaleStep_Private(SNES snes,Vec y,PetscReal *fnorm,PetscReal *delta,PetscReal *gpnorm,PetscReal *ynorm)
4126: {
4127: PetscReal nrm;
4128: PetscScalar cnorm;
4136: VecNorm(y,NORM_2,&nrm);
4137: if (nrm > *delta) {
4138: nrm = *delta/nrm;
4139: *gpnorm = (1.0 - nrm)*(*fnorm);
4140: cnorm = nrm;
4141: VecScale(y,cnorm);
4142: *ynorm = *delta;
4143: } else {
4144: *gpnorm = 0.0;
4145: *ynorm = nrm;
4146: }
4147: return(0);
4148: }
4150: /*@
4151: SNESReasonView - Displays the reason a SNES solve converged or diverged to a viewer
4153: Collective on SNES
4155: Parameter:
4156: + snes - iterative context obtained from SNESCreate()
4157: - viewer - the viewer to display the reason
4160: Options Database Keys:
4161: . -snes_converged_reason - print reason for converged or diverged, also prints number of iterations
4163: Level: beginner
4165: .keywords: SNES, solve, linear system
4167: .seealso: SNESCreate(), SNESSetUp(), SNESDestroy(), SNESSetTolerances(), SNESConvergedDefault()
4169: @*/
4170: PetscErrorCode SNESReasonView(SNES snes,PetscViewer viewer)
4171: {
4172: PetscViewerFormat format;
4173: PetscBool isAscii;
4174: PetscErrorCode ierr;
4177: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&isAscii);
4178: if (isAscii) {
4179: PetscViewerGetFormat(viewer, &format);
4180: PetscViewerASCIIAddTab(viewer,((PetscObject)snes)->tablevel);
4181: if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
4182: DM dm;
4183: Vec u;
4184: PetscDS prob;
4185: PetscInt Nf, f;
4186: PetscErrorCode (**exactFuncs)(PetscInt, PetscReal, const PetscReal[], PetscInt, PetscScalar[], void *);
4187: PetscReal error;
4189: SNESGetDM(snes, &dm);
4190: SNESGetSolution(snes, &u);
4191: DMGetDS(dm, &prob);
4192: PetscDSGetNumFields(prob, &Nf);
4193: PetscMalloc1(Nf, &exactFuncs);
4194: for (f = 0; f < Nf; ++f) {PetscDSGetExactSolution(prob, f, &exactFuncs[f]);}
4195: DMComputeL2Diff(dm, 0.0, exactFuncs, NULL, u, &error);
4196: PetscFree(exactFuncs);
4197: if (error < 1.0e-11) {PetscViewerASCIIPrintf(viewer, "L_2 Error: < 1.0e-11\n");}
4198: else {PetscViewerASCIIPrintf(viewer, "L_2 Error: %g\n", error);}
4199: }
4200: if (snes->reason > 0) {
4201: if (((PetscObject) snes)->prefix) {
4202: PetscViewerASCIIPrintf(viewer,"Nonlinear %s solve converged due to %s iterations %D\n",((PetscObject) snes)->prefix,SNESConvergedReasons[snes->reason],snes->iter);
4203: } else {
4204: PetscViewerASCIIPrintf(viewer,"Nonlinear solve converged due to %s iterations %D\n",SNESConvergedReasons[snes->reason],snes->iter);
4205: }
4206: } else {
4207: if (((PetscObject) snes)->prefix) {
4208: PetscViewerASCIIPrintf(viewer,"Nonlinear %s solve did not converge due to %s iterations %D\n",((PetscObject) snes)->prefix,SNESConvergedReasons[snes->reason],snes->iter);
4209: } else {
4210: PetscViewerASCIIPrintf(viewer,"Nonlinear solve did not converge due to %s iterations %D\n",SNESConvergedReasons[snes->reason],snes->iter);
4211: }
4212: }
4213: PetscViewerASCIISubtractTab(viewer,((PetscObject)snes)->tablevel);
4214: }
4215: return(0);
4216: }
4218: /*@C
4219: SNESReasonViewFromOptions - Processes command line options to determine if/how a SNESReason is to be viewed.
4221: Collective on SNES
4223: Input Parameters:
4224: . snes - the SNES object
4226: Level: intermediate
4228: @*/
4229: PetscErrorCode SNESReasonViewFromOptions(SNES snes)
4230: {
4231: PetscErrorCode ierr;
4232: PetscViewer viewer;
4233: PetscBool flg;
4234: static PetscBool incall = PETSC_FALSE;
4235: PetscViewerFormat format;
4238: if (incall) return(0);
4239: incall = PETSC_TRUE;
4240: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_converged_reason",&viewer,&format,&flg);
4241: if (flg) {
4242: PetscViewerPushFormat(viewer,format);
4243: SNESReasonView(snes,viewer);
4244: PetscViewerPopFormat(viewer);
4245: PetscViewerDestroy(&viewer);
4246: }
4247: incall = PETSC_FALSE;
4248: return(0);
4249: }
4251: /*@
4252: SNESSolve - Solves a nonlinear system F(x) = b.
4253: Call SNESSolve() after calling SNESCreate() and optional routines of the form SNESSetXXX().
4255: Collective on SNES
4257: Input Parameters:
4258: + snes - the SNES context
4259: . b - the constant part of the equation F(x) = b, or NULL to use zero.
4260: - x - the solution vector.
4262: Notes:
4263: The user should initialize the vector,x, with the initial guess
4264: for the nonlinear solve prior to calling SNESSolve. In particular,
4265: to employ an initial guess of zero, the user should explicitly set
4266: this vector to zero by calling VecSet().
4268: Level: beginner
4270: .keywords: SNES, nonlinear, solve
4272: .seealso: SNESCreate(), SNESDestroy(), SNESSetFunction(), SNESSetJacobian(), SNESSetGridSequence(), SNESGetSolution()
4273: @*/
4274: PetscErrorCode SNESSolve(SNES snes,Vec b,Vec x)
4275: {
4276: PetscErrorCode ierr;
4277: PetscBool flg;
4278: PetscInt grid;
4279: Vec xcreated = NULL;
4280: DM dm;
4289: /* High level operations using the nonlinear solver */
4290: {
4291: PetscViewer viewer;
4292: PetscViewerFormat format;
4293: PetscInt num;
4294: PetscBool flg;
4295: static PetscBool incall = PETSC_FALSE;
4297: if (!incall) {
4298: /* Estimate the convergence rate of the discretization */
4299: PetscOptionsGetViewer(PetscObjectComm((PetscObject) snes), ((PetscObject) snes)->prefix, "-snes_convergence_estimate", &viewer, &format, &flg);
4300: if (flg) {
4301: PetscConvEst conv;
4302: DM dm;
4303: PetscReal *alpha; /* Convergence rate of the solution error for each field in the L_2 norm */
4304: PetscInt Nf;
4306: incall = PETSC_TRUE;
4307: SNESGetDM(snes, &dm);
4308: DMGetNumFields(dm, &Nf);
4309: PetscMalloc1(Nf, &alpha);
4310: PetscConvEstCreate(PetscObjectComm((PetscObject) snes), &conv);
4311: PetscConvEstSetSolver(conv, snes);
4312: PetscConvEstSetFromOptions(conv);
4313: PetscConvEstSetUp(conv);
4314: PetscConvEstGetConvRate(conv, alpha);
4315: PetscViewerPushFormat(viewer, format);
4316: PetscConvEstRateView(conv, alpha, viewer);
4317: PetscViewerPopFormat(viewer);
4318: PetscViewerDestroy(&viewer);
4319: PetscConvEstDestroy(&conv);
4320: PetscFree(alpha);
4321: incall = PETSC_FALSE;
4322: }
4323: /* Adaptively refine the initial grid */
4324: num = 1;
4325: PetscOptionsGetInt(NULL, ((PetscObject) snes)->prefix, "-snes_adapt_initial", &num, &flg);
4326: if (flg) {
4327: DMAdaptor adaptor;
4329: incall = PETSC_TRUE;
4330: DMAdaptorCreate(PETSC_COMM_WORLD, &adaptor);
4331: DMAdaptorSetSolver(adaptor, snes);
4332: DMAdaptorSetSequenceLength(adaptor, num);
4333: DMAdaptorSetFromOptions(adaptor);
4334: DMAdaptorSetUp(adaptor);
4335: DMAdaptorAdapt(adaptor, x, DM_ADAPTATION_INITIAL, &dm, &x);
4336: DMAdaptorDestroy(&adaptor);
4337: incall = PETSC_FALSE;
4338: }
4339: /* Use grid sequencing to adapt */
4340: num = 0;
4341: PetscOptionsGetInt(NULL, ((PetscObject) snes)->prefix, "-snes_adapt_sequence", &num, NULL);
4342: if (num) {
4343: DMAdaptor adaptor;
4345: incall = PETSC_TRUE;
4346: DMAdaptorCreate(PETSC_COMM_WORLD, &adaptor);
4347: DMAdaptorSetSolver(adaptor, snes);
4348: DMAdaptorSetSequenceLength(adaptor, num);
4349: DMAdaptorSetFromOptions(adaptor);
4350: DMAdaptorSetUp(adaptor);
4351: DMAdaptorAdapt(adaptor, x, DM_ADAPTATION_SEQUENTIAL, &dm, &x);
4352: DMAdaptorDestroy(&adaptor);
4353: incall = PETSC_FALSE;
4354: }
4355: }
4356: }
4357: if (!x) {
4358: SNESGetDM(snes,&dm);
4359: DMCreateGlobalVector(dm,&xcreated);
4360: x = xcreated;
4361: }
4362: SNESViewFromOptions(snes,NULL,"-snes_view_pre");
4364: for (grid=0; grid<snes->gridsequence; grid++) {PetscViewerASCIIPushTab(PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)snes)));}
4365: for (grid=0; grid<snes->gridsequence+1; grid++) {
4367: /* set solution vector */
4368: if (!grid) {PetscObjectReference((PetscObject)x);}
4369: VecDestroy(&snes->vec_sol);
4370: snes->vec_sol = x;
4371: SNESGetDM(snes,&dm);
4373: /* set affine vector if provided */
4374: if (b) { PetscObjectReference((PetscObject)b); }
4375: VecDestroy(&snes->vec_rhs);
4376: snes->vec_rhs = b;
4378: if (snes->vec_func == snes->vec_sol) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_IDN,"Solution vector cannot be function vector");
4379: if (snes->vec_rhs == snes->vec_sol) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_IDN,"Solution vector cannot be right hand side vector");
4380: if (!snes->vec_sol_update /* && snes->vec_sol */) {
4381: VecDuplicate(snes->vec_sol,&snes->vec_sol_update);
4382: PetscLogObjectParent((PetscObject)snes,(PetscObject)snes->vec_sol_update);
4383: }
4384: DMShellSetGlobalVector(dm,snes->vec_sol);
4385: SNESSetUp(snes);
4387: if (!grid) {
4388: if (snes->ops->computeinitialguess) {
4389: (*snes->ops->computeinitialguess)(snes,snes->vec_sol,snes->initialguessP);
4390: }
4391: }
4393: if (snes->conv_hist_reset) snes->conv_hist_len = 0;
4394: if (snes->counters_reset) {snes->nfuncs = 0; snes->linear_its = 0; snes->numFailures = 0;}
4396: PetscLogEventBegin(SNES_Solve,snes,0,0,0);
4397: (*snes->ops->solve)(snes);
4398: PetscLogEventEnd(SNES_Solve,snes,0,0,0);
4399: if (!snes->reason) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Internal error, solver returned without setting converged reason");
4400: snes->domainerror = PETSC_FALSE; /* clear the flag if it has been set */
4402: if (snes->lagjac_persist) snes->jac_iter += snes->iter;
4403: if (snes->lagpre_persist) snes->pre_iter += snes->iter;
4405: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_test_local_min",NULL,NULL,&flg);
4406: if (flg && !PetscPreLoadingOn) { SNESTestLocalMin(snes); }
4407: SNESReasonViewFromOptions(snes);
4409: if (snes->errorifnotconverged && snes->reason < 0) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_NOT_CONVERGED,"SNESSolve has not converged");
4410: if (snes->reason < 0) break;
4411: if (grid < snes->gridsequence) {
4412: DM fine;
4413: Vec xnew;
4414: Mat interp;
4416: DMRefine(snes->dm,PetscObjectComm((PetscObject)snes),&fine);
4417: if (!fine) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_INCOMP,"DMRefine() did not perform any refinement, cannot continue grid sequencing");
4418: DMCreateInterpolation(snes->dm,fine,&interp,NULL);
4419: DMCreateGlobalVector(fine,&xnew);
4420: MatInterpolate(interp,x,xnew);
4421: DMInterpolate(snes->dm,interp,fine);
4422: MatDestroy(&interp);
4423: x = xnew;
4425: SNESReset(snes);
4426: SNESSetDM(snes,fine);
4427: SNESResetFromOptions(snes);
4428: DMDestroy(&fine);
4429: PetscViewerASCIIPopTab(PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)snes)));
4430: }
4431: }
4432: SNESViewFromOptions(snes,NULL,"-snes_view");
4433: VecViewFromOptions(snes->vec_sol,(PetscObject)snes,"-snes_view_solution");
4435: VecDestroy(&xcreated);
4436: PetscObjectSAWsBlock((PetscObject)snes);
4437: return(0);
4438: }
4440: /* --------- Internal routines for SNES Package --------- */
4442: /*@C
4443: SNESSetType - Sets the method for the nonlinear solver.
4445: Collective on SNES
4447: Input Parameters:
4448: + snes - the SNES context
4449: - type - a known method
4451: Options Database Key:
4452: . -snes_type <type> - Sets the method; use -help for a list
4453: of available methods (for instance, newtonls or newtontr)
4455: Notes:
4456: See "petsc/include/petscsnes.h" for available methods (for instance)
4457: + SNESNEWTONLS - Newton's method with line search
4458: (systems of nonlinear equations)
4459: . SNESNEWTONTR - Newton's method with trust region
4460: (systems of nonlinear equations)
4462: Normally, it is best to use the SNESSetFromOptions() command and then
4463: set the SNES solver type from the options database rather than by using
4464: this routine. Using the options database provides the user with
4465: maximum flexibility in evaluating the many nonlinear solvers.
4466: The SNESSetType() routine is provided for those situations where it
4467: is necessary to set the nonlinear solver independently of the command
4468: line or options database. This might be the case, for example, when
4469: the choice of solver changes during the execution of the program,
4470: and the user's application is taking responsibility for choosing the
4471: appropriate method.
4473: Developer Notes:
4474: SNESRegister() adds a constructor for a new SNESType to SNESList, SNESSetType() locates
4475: the constructor in that list and calls it to create the spexific object.
4477: Level: intermediate
4479: .keywords: SNES, set, type
4481: .seealso: SNESType, SNESCreate(), SNESDestroy(), SNESGetType(), SNESSetFromOptions()
4483: @*/
4484: PetscErrorCode SNESSetType(SNES snes,SNESType type)
4485: {
4486: PetscErrorCode ierr,(*r)(SNES);
4487: PetscBool match;
4493: PetscObjectTypeCompare((PetscObject)snes,type,&match);
4494: if (match) return(0);
4496: PetscFunctionListFind(SNESList,type,&r);
4497: if (!r) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_UNKNOWN_TYPE,"Unable to find requested SNES type %s",type);
4498: /* Destroy the previous private SNES context */
4499: if (snes->ops->destroy) {
4500: (*(snes)->ops->destroy)(snes);
4501: snes->ops->destroy = NULL;
4502: }
4503: /* Reinitialize function pointers in SNESOps structure */
4504: snes->ops->setup = 0;
4505: snes->ops->solve = 0;
4506: snes->ops->view = 0;
4507: snes->ops->setfromoptions = 0;
4508: snes->ops->destroy = 0;
4509: /* Call the SNESCreate_XXX routine for this particular Nonlinear solver */
4510: snes->setupcalled = PETSC_FALSE;
4512: PetscObjectChangeTypeName((PetscObject)snes,type);
4513: (*r)(snes);
4514: return(0);
4515: }
4517: /*@C
4518: SNESGetType - Gets the SNES method type and name (as a string).
4520: Not Collective
4522: Input Parameter:
4523: . snes - nonlinear solver context
4525: Output Parameter:
4526: . type - SNES method (a character string)
4528: Level: intermediate
4530: .keywords: SNES, nonlinear, get, type, name
4531: @*/
4532: PetscErrorCode SNESGetType(SNES snes,SNESType *type)
4533: {
4537: *type = ((PetscObject)snes)->type_name;
4538: return(0);
4539: }
4541: /*@
4542: SNESSetSolution - Sets the solution vector for use by the SNES routines.
4544: Logically Collective on SNES and Vec
4546: Input Parameters:
4547: + snes - the SNES context obtained from SNESCreate()
4548: - u - the solution vector
4550: Level: beginner
4552: .keywords: SNES, set, solution
4553: @*/
4554: PetscErrorCode SNESSetSolution(SNES snes, Vec u)
4555: {
4556: DM dm;
4562: PetscObjectReference((PetscObject) u);
4563: VecDestroy(&snes->vec_sol);
4565: snes->vec_sol = u;
4567: SNESGetDM(snes, &dm);
4568: DMShellSetGlobalVector(dm, u);
4569: return(0);
4570: }
4572: /*@
4573: SNESGetSolution - Returns the vector where the approximate solution is
4574: stored. This is the fine grid solution when using SNESSetGridSequence().
4576: Not Collective, but Vec is parallel if SNES is parallel
4578: Input Parameter:
4579: . snes - the SNES context
4581: Output Parameter:
4582: . x - the solution
4584: Level: intermediate
4586: .keywords: SNES, nonlinear, get, solution
4588: .seealso: SNESGetSolutionUpdate(), SNESGetFunction()
4589: @*/
4590: PetscErrorCode SNESGetSolution(SNES snes,Vec *x)
4591: {
4595: *x = snes->vec_sol;
4596: return(0);
4597: }
4599: /*@
4600: SNESGetSolutionUpdate - Returns the vector where the solution update is
4601: stored.
4603: Not Collective, but Vec is parallel if SNES is parallel
4605: Input Parameter:
4606: . snes - the SNES context
4608: Output Parameter:
4609: . x - the solution update
4611: Level: advanced
4613: .keywords: SNES, nonlinear, get, solution, update
4615: .seealso: SNESGetSolution(), SNESGetFunction()
4616: @*/
4617: PetscErrorCode SNESGetSolutionUpdate(SNES snes,Vec *x)
4618: {
4622: *x = snes->vec_sol_update;
4623: return(0);
4624: }
4626: /*@C
4627: SNESGetFunction - Returns the vector where the function is stored.
4629: Not Collective, but Vec is parallel if SNES is parallel. Collective if Vec is requested, but has not been created yet.
4631: Input Parameter:
4632: . snes - the SNES context
4634: Output Parameter:
4635: + r - the vector that is used to store residuals (or NULL if you don't want it)
4636: . f - the function (or NULL if you don't want it); see SNESFunction for calling sequence details
4637: - ctx - the function context (or NULL if you don't want it)
4639: Level: advanced
4641: Notes: The vector r DOES NOT, in general contain the current value of the SNES nonlinear function
4643: .keywords: SNES, nonlinear, get, function
4645: .seealso: SNESSetFunction(), SNESGetSolution(), SNESFunction
4646: @*/
4647: PetscErrorCode SNESGetFunction(SNES snes,Vec *r,PetscErrorCode (**f)(SNES,Vec,Vec,void*),void **ctx)
4648: {
4650: DM dm;
4654: if (r) {
4655: if (!snes->vec_func) {
4656: if (snes->vec_rhs) {
4657: VecDuplicate(snes->vec_rhs,&snes->vec_func);
4658: } else if (snes->vec_sol) {
4659: VecDuplicate(snes->vec_sol,&snes->vec_func);
4660: } else if (snes->dm) {
4661: DMCreateGlobalVector(snes->dm,&snes->vec_func);
4662: }
4663: }
4664: *r = snes->vec_func;
4665: }
4666: SNESGetDM(snes,&dm);
4667: DMSNESGetFunction(dm,f,ctx);
4668: return(0);
4669: }
4671: /*@C
4672: SNESGetNGS - Returns the NGS function and context.
4674: Input Parameter:
4675: . snes - the SNES context
4677: Output Parameter:
4678: + f - the function (or NULL) see SNESNGSFunction for details
4679: - ctx - the function context (or NULL)
4681: Level: advanced
4683: .keywords: SNES, nonlinear, get, function
4685: .seealso: SNESSetNGS(), SNESGetFunction()
4686: @*/
4688: PetscErrorCode SNESGetNGS (SNES snes, PetscErrorCode (**f)(SNES, Vec, Vec, void*), void ** ctx)
4689: {
4691: DM dm;
4695: SNESGetDM(snes,&dm);
4696: DMSNESGetNGS(dm,f,ctx);
4697: return(0);
4698: }
4700: /*@C
4701: SNESSetOptionsPrefix - Sets the prefix used for searching for all
4702: SNES options in the database.
4704: Logically Collective on SNES
4706: Input Parameter:
4707: + snes - the SNES context
4708: - prefix - the prefix to prepend to all option names
4710: Notes:
4711: A hyphen (-) must NOT be given at the beginning of the prefix name.
4712: The first character of all runtime options is AUTOMATICALLY the hyphen.
4714: Level: advanced
4716: .keywords: SNES, set, options, prefix, database
4718: .seealso: SNESSetFromOptions()
4719: @*/
4720: PetscErrorCode SNESSetOptionsPrefix(SNES snes,const char prefix[])
4721: {
4726: PetscObjectSetOptionsPrefix((PetscObject)snes,prefix);
4727: if (!snes->ksp) {SNESGetKSP(snes,&snes->ksp);}
4728: if (snes->linesearch) {
4729: SNESGetLineSearch(snes,&snes->linesearch);
4730: PetscObjectSetOptionsPrefix((PetscObject)snes->linesearch,prefix);
4731: }
4732: KSPSetOptionsPrefix(snes->ksp,prefix);
4733: return(0);
4734: }
4736: /*@C
4737: SNESAppendOptionsPrefix - Appends to the prefix used for searching for all
4738: SNES options in the database.
4740: Logically Collective on SNES
4742: Input Parameters:
4743: + snes - the SNES context
4744: - prefix - the prefix to prepend to all option names
4746: Notes:
4747: A hyphen (-) must NOT be given at the beginning of the prefix name.
4748: The first character of all runtime options is AUTOMATICALLY the hyphen.
4750: Level: advanced
4752: .keywords: SNES, append, options, prefix, database
4754: .seealso: SNESGetOptionsPrefix()
4755: @*/
4756: PetscErrorCode SNESAppendOptionsPrefix(SNES snes,const char prefix[])
4757: {
4762: PetscObjectAppendOptionsPrefix((PetscObject)snes,prefix);
4763: if (!snes->ksp) {SNESGetKSP(snes,&snes->ksp);}
4764: if (snes->linesearch) {
4765: SNESGetLineSearch(snes,&snes->linesearch);
4766: PetscObjectAppendOptionsPrefix((PetscObject)snes->linesearch,prefix);
4767: }
4768: KSPAppendOptionsPrefix(snes->ksp,prefix);
4769: return(0);
4770: }
4772: /*@C
4773: SNESGetOptionsPrefix - Sets the prefix used for searching for all
4774: SNES options in the database.
4776: Not Collective
4778: Input Parameter:
4779: . snes - the SNES context
4781: Output Parameter:
4782: . prefix - pointer to the prefix string used
4784: Notes:
4785: On the fortran side, the user should pass in a string 'prefix' of
4786: sufficient length to hold the prefix.
4788: Level: advanced
4790: .keywords: SNES, get, options, prefix, database
4792: .seealso: SNESAppendOptionsPrefix()
4793: @*/
4794: PetscErrorCode SNESGetOptionsPrefix(SNES snes,const char *prefix[])
4795: {
4800: PetscObjectGetOptionsPrefix((PetscObject)snes,prefix);
4801: return(0);
4802: }
4805: /*@C
4806: SNESRegister - Adds a method to the nonlinear solver package.
4808: Not collective
4810: Input Parameters:
4811: + name_solver - name of a new user-defined solver
4812: - routine_create - routine to create method context
4814: Notes:
4815: SNESRegister() may be called multiple times to add several user-defined solvers.
4817: Sample usage:
4818: .vb
4819: SNESRegister("my_solver",MySolverCreate);
4820: .ve
4822: Then, your solver can be chosen with the procedural interface via
4823: $ SNESSetType(snes,"my_solver")
4824: or at runtime via the option
4825: $ -snes_type my_solver
4827: Level: advanced
4829: Note: If your function is not being put into a shared library then use SNESRegister() instead
4831: .keywords: SNES, nonlinear, register
4833: .seealso: SNESRegisterAll(), SNESRegisterDestroy()
4835: Level: advanced
4836: @*/
4837: PetscErrorCode SNESRegister(const char sname[],PetscErrorCode (*function)(SNES))
4838: {
4842: SNESInitializePackage();
4843: PetscFunctionListAdd(&SNESList,sname,function);
4844: return(0);
4845: }
4847: PetscErrorCode SNESTestLocalMin(SNES snes)
4848: {
4850: PetscInt N,i,j;
4851: Vec u,uh,fh;
4852: PetscScalar value;
4853: PetscReal norm;
4856: SNESGetSolution(snes,&u);
4857: VecDuplicate(u,&uh);
4858: VecDuplicate(u,&fh);
4860: /* currently only works for sequential */
4861: PetscPrintf(PETSC_COMM_WORLD,"Testing FormFunction() for local min\n");
4862: VecGetSize(u,&N);
4863: for (i=0; i<N; i++) {
4864: VecCopy(u,uh);
4865: PetscPrintf(PETSC_COMM_WORLD,"i = %D\n",i);
4866: for (j=-10; j<11; j++) {
4867: value = PetscSign(j)*PetscExpReal(PetscAbs(j)-10.0);
4868: VecSetValue(uh,i,value,ADD_VALUES);
4869: SNESComputeFunction(snes,uh,fh);
4870: VecNorm(fh,NORM_2,&norm);
4871: PetscPrintf(PETSC_COMM_WORLD," j norm %D %18.16e\n",j,norm);
4872: value = -value;
4873: VecSetValue(uh,i,value,ADD_VALUES);
4874: }
4875: }
4876: VecDestroy(&uh);
4877: VecDestroy(&fh);
4878: return(0);
4879: }
4881: /*@
4882: SNESKSPSetUseEW - Sets SNES use Eisenstat-Walker method for
4883: computing relative tolerance for linear solvers within an inexact
4884: Newton method.
4886: Logically Collective on SNES
4888: Input Parameters:
4889: + snes - SNES context
4890: - flag - PETSC_TRUE or PETSC_FALSE
4892: Options Database:
4893: + -snes_ksp_ew - use Eisenstat-Walker method for determining linear system convergence
4894: . -snes_ksp_ew_version ver - version of Eisenstat-Walker method
4895: . -snes_ksp_ew_rtol0 <rtol0> - Sets rtol0
4896: . -snes_ksp_ew_rtolmax <rtolmax> - Sets rtolmax
4897: . -snes_ksp_ew_gamma <gamma> - Sets gamma
4898: . -snes_ksp_ew_alpha <alpha> - Sets alpha
4899: . -snes_ksp_ew_alpha2 <alpha2> - Sets alpha2
4900: - -snes_ksp_ew_threshold <threshold> - Sets threshold
4902: Notes:
4903: Currently, the default is to use a constant relative tolerance for
4904: the inner linear solvers. Alternatively, one can use the
4905: Eisenstat-Walker method, where the relative convergence tolerance
4906: is reset at each Newton iteration according progress of the nonlinear
4907: solver.
4909: Level: advanced
4911: Reference:
4912: S. C. Eisenstat and H. F. Walker, "Choosing the forcing terms in an
4913: inexact Newton method", SISC 17 (1), pp.16-32, 1996.
4915: .keywords: SNES, KSP, Eisenstat, Walker, convergence, test, inexact, Newton
4917: .seealso: SNESKSPGetUseEW(), SNESKSPGetParametersEW(), SNESKSPSetParametersEW()
4918: @*/
4919: PetscErrorCode SNESKSPSetUseEW(SNES snes,PetscBool flag)
4920: {
4924: snes->ksp_ewconv = flag;
4925: return(0);
4926: }
4928: /*@
4929: SNESKSPGetUseEW - Gets if SNES is using Eisenstat-Walker method
4930: for computing relative tolerance for linear solvers within an
4931: inexact Newton method.
4933: Not Collective
4935: Input Parameter:
4936: . snes - SNES context
4938: Output Parameter:
4939: . flag - PETSC_TRUE or PETSC_FALSE
4941: Notes:
4942: Currently, the default is to use a constant relative tolerance for
4943: the inner linear solvers. Alternatively, one can use the
4944: Eisenstat-Walker method, where the relative convergence tolerance
4945: is reset at each Newton iteration according progress of the nonlinear
4946: solver.
4948: Level: advanced
4950: Reference:
4951: S. C. Eisenstat and H. F. Walker, "Choosing the forcing terms in an
4952: inexact Newton method", SISC 17 (1), pp.16-32, 1996.
4954: .keywords: SNES, KSP, Eisenstat, Walker, convergence, test, inexact, Newton
4956: .seealso: SNESKSPSetUseEW(), SNESKSPGetParametersEW(), SNESKSPSetParametersEW()
4957: @*/
4958: PetscErrorCode SNESKSPGetUseEW(SNES snes, PetscBool *flag)
4959: {
4963: *flag = snes->ksp_ewconv;
4964: return(0);
4965: }
4967: /*@
4968: SNESKSPSetParametersEW - Sets parameters for Eisenstat-Walker
4969: convergence criteria for the linear solvers within an inexact
4970: Newton method.
4972: Logically Collective on SNES
4974: Input Parameters:
4975: + snes - SNES context
4976: . version - version 1, 2 (default is 2) or 3
4977: . rtol_0 - initial relative tolerance (0 <= rtol_0 < 1)
4978: . rtol_max - maximum relative tolerance (0 <= rtol_max < 1)
4979: . gamma - multiplicative factor for version 2 rtol computation
4980: (0 <= gamma2 <= 1)
4981: . alpha - power for version 2 rtol computation (1 < alpha <= 2)
4982: . alpha2 - power for safeguard
4983: - threshold - threshold for imposing safeguard (0 < threshold < 1)
4985: Note:
4986: Version 3 was contributed by Luis Chacon, June 2006.
4988: Use PETSC_DEFAULT to retain the default for any of the parameters.
4990: Level: advanced
4992: Reference:
4993: S. C. Eisenstat and H. F. Walker, "Choosing the forcing terms in an
4994: inexact Newton method", Utah State University Math. Stat. Dept. Res.
4995: Report 6/94/75, June, 1994, to appear in SIAM J. Sci. Comput.
4997: .keywords: SNES, KSP, Eisenstat, Walker, set, parameters
4999: .seealso: SNESKSPSetUseEW(), SNESKSPGetUseEW(), SNESKSPGetParametersEW()
5000: @*/
5001: PetscErrorCode SNESKSPSetParametersEW(SNES snes,PetscInt version,PetscReal rtol_0,PetscReal rtol_max,PetscReal gamma,PetscReal alpha,PetscReal alpha2,PetscReal threshold)
5002: {
5003: SNESKSPEW *kctx;
5007: kctx = (SNESKSPEW*)snes->kspconvctx;
5008: if (!kctx) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"No Eisenstat-Walker context existing");
5017: if (version != PETSC_DEFAULT) kctx->version = version;
5018: if (rtol_0 != PETSC_DEFAULT) kctx->rtol_0 = rtol_0;
5019: if (rtol_max != PETSC_DEFAULT) kctx->rtol_max = rtol_max;
5020: if (gamma != PETSC_DEFAULT) kctx->gamma = gamma;
5021: if (alpha != PETSC_DEFAULT) kctx->alpha = alpha;
5022: if (alpha2 != PETSC_DEFAULT) kctx->alpha2 = alpha2;
5023: if (threshold != PETSC_DEFAULT) kctx->threshold = threshold;
5025: 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);
5026: 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);
5027: 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);
5028: 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);
5029: 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);
5030: 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);
5031: return(0);
5032: }
5034: /*@
5035: SNESKSPGetParametersEW - Gets parameters for Eisenstat-Walker
5036: convergence criteria for the linear solvers within an inexact
5037: Newton method.
5039: Not Collective
5041: Input Parameters:
5042: snes - SNES context
5044: Output Parameters:
5045: + version - version 1, 2 (default is 2) or 3
5046: . rtol_0 - initial relative tolerance (0 <= rtol_0 < 1)
5047: . rtol_max - maximum relative tolerance (0 <= rtol_max < 1)
5048: . gamma - multiplicative factor for version 2 rtol computation (0 <= gamma2 <= 1)
5049: . alpha - power for version 2 rtol computation (1 < alpha <= 2)
5050: . alpha2 - power for safeguard
5051: - threshold - threshold for imposing safeguard (0 < threshold < 1)
5053: Level: advanced
5055: .keywords: SNES, KSP, Eisenstat, Walker, get, parameters
5057: .seealso: SNESKSPSetUseEW(), SNESKSPGetUseEW(), SNESKSPSetParametersEW()
5058: @*/
5059: PetscErrorCode SNESKSPGetParametersEW(SNES snes,PetscInt *version,PetscReal *rtol_0,PetscReal *rtol_max,PetscReal *gamma,PetscReal *alpha,PetscReal *alpha2,PetscReal *threshold)
5060: {
5061: SNESKSPEW *kctx;
5065: kctx = (SNESKSPEW*)snes->kspconvctx;
5066: if (!kctx) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"No Eisenstat-Walker context existing");
5067: if (version) *version = kctx->version;
5068: if (rtol_0) *rtol_0 = kctx->rtol_0;
5069: if (rtol_max) *rtol_max = kctx->rtol_max;
5070: if (gamma) *gamma = kctx->gamma;
5071: if (alpha) *alpha = kctx->alpha;
5072: if (alpha2) *alpha2 = kctx->alpha2;
5073: if (threshold) *threshold = kctx->threshold;
5074: return(0);
5075: }
5077: PetscErrorCode KSPPreSolve_SNESEW(KSP ksp, Vec b, Vec x, SNES snes)
5078: {
5080: SNESKSPEW *kctx = (SNESKSPEW*)snes->kspconvctx;
5081: PetscReal rtol = PETSC_DEFAULT,stol;
5084: if (!snes->ksp_ewconv) return(0);
5085: if (!snes->iter) {
5086: rtol = kctx->rtol_0; /* first time in, so use the original user rtol */
5087: VecNorm(snes->vec_func,NORM_2,&kctx->norm_first);
5088: }
5089: else {
5090: if (kctx->version == 1) {
5091: rtol = (snes->norm - kctx->lresid_last)/kctx->norm_last;
5092: if (rtol < 0.0) rtol = -rtol;
5093: stol = PetscPowReal(kctx->rtol_last,kctx->alpha2);
5094: if (stol > kctx->threshold) rtol = PetscMax(rtol,stol);
5095: } else if (kctx->version == 2) {
5096: rtol = kctx->gamma * PetscPowReal(snes->norm/kctx->norm_last,kctx->alpha);
5097: stol = kctx->gamma * PetscPowReal(kctx->rtol_last,kctx->alpha);
5098: if (stol > kctx->threshold) rtol = PetscMax(rtol,stol);
5099: } else if (kctx->version == 3) { /* contributed by Luis Chacon, June 2006. */
5100: rtol = kctx->gamma * PetscPowReal(snes->norm/kctx->norm_last,kctx->alpha);
5101: /* safeguard: avoid sharp decrease of rtol */
5102: stol = kctx->gamma*PetscPowReal(kctx->rtol_last,kctx->alpha);
5103: stol = PetscMax(rtol,stol);
5104: rtol = PetscMin(kctx->rtol_0,stol);
5105: /* safeguard: avoid oversolving */
5106: stol = kctx->gamma*(kctx->norm_first*snes->rtol)/snes->norm;
5107: stol = PetscMax(rtol,stol);
5108: rtol = PetscMin(kctx->rtol_0,stol);
5109: } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Only versions 1, 2 or 3 are supported: %D",kctx->version);
5110: }
5111: /* safeguard: avoid rtol greater than one */
5112: rtol = PetscMin(rtol,kctx->rtol_max);
5113: KSPSetTolerances(ksp,rtol,PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT);
5114: PetscInfo3(snes,"iter %D, Eisenstat-Walker (version %D) KSP rtol=%g\n",snes->iter,kctx->version,(double)rtol);
5115: return(0);
5116: }
5118: PetscErrorCode KSPPostSolve_SNESEW(KSP ksp, Vec b, Vec x, SNES snes)
5119: {
5121: SNESKSPEW *kctx = (SNESKSPEW*)snes->kspconvctx;
5122: PCSide pcside;
5123: Vec lres;
5126: if (!snes->ksp_ewconv) return(0);
5127: KSPGetTolerances(ksp,&kctx->rtol_last,0,0,0);
5128: kctx->norm_last = snes->norm;
5129: if (kctx->version == 1) {
5130: PC pc;
5131: PetscBool isNone;
5133: KSPGetPC(ksp, &pc);
5134: PetscObjectTypeCompare((PetscObject) pc, PCNONE, &isNone);
5135: KSPGetPCSide(ksp,&pcside);
5136: if (pcside == PC_RIGHT || isNone) { /* XXX Should we also test KSP_UNPRECONDITIONED_NORM ? */
5137: /* KSP residual is true linear residual */
5138: KSPGetResidualNorm(ksp,&kctx->lresid_last);
5139: } else {
5140: /* KSP residual is preconditioned residual */
5141: /* compute true linear residual norm */
5142: VecDuplicate(b,&lres);
5143: MatMult(snes->jacobian,x,lres);
5144: VecAYPX(lres,-1.0,b);
5145: VecNorm(lres,NORM_2,&kctx->lresid_last);
5146: VecDestroy(&lres);
5147: }
5148: }
5149: return(0);
5150: }
5152: /*@
5153: SNESGetKSP - Returns the KSP context for a SNES solver.
5155: Not Collective, but if SNES object is parallel, then KSP object is parallel
5157: Input Parameter:
5158: . snes - the SNES context
5160: Output Parameter:
5161: . ksp - the KSP context
5163: Notes:
5164: The user can then directly manipulate the KSP context to set various
5165: options, etc. Likewise, the user can then extract and manipulate the
5166: PC contexts as well.
5168: Level: beginner
5170: .keywords: SNES, nonlinear, get, KSP, context
5172: .seealso: KSPGetPC(), SNESCreate(), KSPCreate(), SNESSetKSP()
5173: @*/
5174: PetscErrorCode SNESGetKSP(SNES snes,KSP *ksp)
5175: {
5182: if (!snes->ksp) {
5183: PetscBool monitor = PETSC_FALSE;
5185: KSPCreate(PetscObjectComm((PetscObject)snes),&snes->ksp);
5186: PetscObjectIncrementTabLevel((PetscObject)snes->ksp,(PetscObject)snes,1);
5187: PetscLogObjectParent((PetscObject)snes,(PetscObject)snes->ksp);
5189: KSPSetPreSolve(snes->ksp,(PetscErrorCode (*)(KSP,Vec,Vec,void*))KSPPreSolve_SNESEW,snes);
5190: KSPSetPostSolve(snes->ksp,(PetscErrorCode (*)(KSP,Vec,Vec,void*))KSPPostSolve_SNESEW,snes);
5192: PetscOptionsGetBool(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-ksp_monitor_snes",&monitor,NULL);
5193: if (monitor) {
5194: KSPMonitorSet(snes->ksp,KSPMonitorSNES,snes,NULL);
5195: }
5196: monitor = PETSC_FALSE;
5197: PetscOptionsGetBool(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-ksp_monitor_snes_lg",&monitor,NULL);
5198: if (monitor) {
5199: PetscObject *objs;
5200: KSPMonitorSNESLGResidualNormCreate(PetscObjectComm((PetscObject)snes),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,600,600,&objs);
5201: objs[0] = (PetscObject) snes;
5202: KSPMonitorSet(snes->ksp,(PetscErrorCode (*)(KSP,PetscInt,PetscReal,void*))KSPMonitorSNESLGResidualNorm,objs,(PetscErrorCode (*)(void**))KSPMonitorSNESLGResidualNormDestroy);
5203: }
5204: }
5205: *ksp = snes->ksp;
5206: return(0);
5207: }
5210: #include <petsc/private/dmimpl.h>
5211: /*@
5212: SNESSetDM - Sets the DM that may be used by some nonlinear solvers or their underlying preconditioners
5214: Logically Collective on SNES
5216: Input Parameters:
5217: + snes - the nonlinear solver context
5218: - dm - the dm, cannot be NULL
5220: Notes:
5221: A DM can only be used for solving one problem at a time because information about the problem is stored on the DM,
5222: even when not using interfaces like DMSNESSetFunction(). Use DMClone() to get a distinct DM when solving different
5223: problems using the same function space.
5225: Level: intermediate
5227: .seealso: SNESGetDM(), KSPSetDM(), KSPGetDM()
5228: @*/
5229: PetscErrorCode SNESSetDM(SNES snes,DM dm)
5230: {
5232: KSP ksp;
5233: DMSNES sdm;
5238: PetscObjectReference((PetscObject)dm);
5239: if (snes->dm) { /* Move the DMSNES context over to the new DM unless the new DM already has one */
5240: if (snes->dm->dmsnes && !dm->dmsnes) {
5241: DMCopyDMSNES(snes->dm,dm);
5242: DMGetDMSNES(snes->dm,&sdm);
5243: if (sdm->originaldm == snes->dm) sdm->originaldm = dm; /* Grant write privileges to the replacement DM */
5244: }
5245: DMCoarsenHookRemove(snes->dm,DMCoarsenHook_SNESVecSol,DMRestrictHook_SNESVecSol,snes);
5246: DMDestroy(&snes->dm);
5247: }
5248: snes->dm = dm;
5249: snes->dmAuto = PETSC_FALSE;
5251: SNESGetKSP(snes,&ksp);
5252: KSPSetDM(ksp,dm);
5253: KSPSetDMActive(ksp,PETSC_FALSE);
5254: if (snes->npc) {
5255: SNESSetDM(snes->npc, snes->dm);
5256: SNESSetNPCSide(snes,snes->npcside);
5257: }
5258: return(0);
5259: }
5261: /*@
5262: SNESGetDM - Gets the DM that may be used by some preconditioners
5264: Not Collective but DM obtained is parallel on SNES
5266: Input Parameter:
5267: . snes - the preconditioner context
5269: Output Parameter:
5270: . dm - the dm
5272: Level: intermediate
5274: .seealso: SNESSetDM(), KSPSetDM(), KSPGetDM()
5275: @*/
5276: PetscErrorCode SNESGetDM(SNES snes,DM *dm)
5277: {
5282: if (!snes->dm) {
5283: DMShellCreate(PetscObjectComm((PetscObject)snes),&snes->dm);
5284: snes->dmAuto = PETSC_TRUE;
5285: }
5286: *dm = snes->dm;
5287: return(0);
5288: }
5290: /*@
5291: SNESSetNPC - Sets the nonlinear preconditioner to be used.
5293: Collective on SNES
5295: Input Parameters:
5296: + snes - iterative context obtained from SNESCreate()
5297: - pc - the preconditioner object
5299: Notes:
5300: Use SNESGetNPC() to retrieve the preconditioner context (for example,
5301: to configure it using the API).
5303: Level: developer
5305: .keywords: SNES, set, precondition
5306: .seealso: SNESGetNPC(), SNESHasNPC()
5307: @*/
5308: PetscErrorCode SNESSetNPC(SNES snes, SNES pc)
5309: {
5316: PetscObjectReference((PetscObject) pc);
5317: SNESDestroy(&snes->npc);
5318: snes->npc = pc;
5319: PetscLogObjectParent((PetscObject)snes, (PetscObject)snes->npc);
5320: return(0);
5321: }
5323: /*@
5324: SNESGetNPC - Creates a nonlinear preconditioning solver (SNES) to be used to precondition the nonlinear solver.
5326: Not Collective
5328: Input Parameter:
5329: . snes - iterative context obtained from SNESCreate()
5331: Output Parameter:
5332: . pc - preconditioner context
5334: Notes:
5335: If a SNES was previously set with SNESSetNPC() then that SNES is returned.
5337: Level: developer
5339: .keywords: SNES, get, preconditioner
5340: .seealso: SNESSetNPC(), SNESHasNPC()
5341: @*/
5342: PetscErrorCode SNESGetNPC(SNES snes, SNES *pc)
5343: {
5345: const char *optionsprefix;
5350: if (!snes->npc) {
5351: SNESCreate(PetscObjectComm((PetscObject)snes),&snes->npc);
5352: PetscObjectIncrementTabLevel((PetscObject)snes->npc,(PetscObject)snes,1);
5353: PetscLogObjectParent((PetscObject)snes,(PetscObject)snes->npc);
5354: SNESGetOptionsPrefix(snes,&optionsprefix);
5355: SNESSetOptionsPrefix(snes->npc,optionsprefix);
5356: SNESAppendOptionsPrefix(snes->npc,"npc_");
5357: SNESSetCountersReset(snes->npc,PETSC_FALSE);
5358: }
5359: *pc = snes->npc;
5360: return(0);
5361: }
5363: /*@
5364: SNESHasNPC - Returns whether a nonlinear preconditioner exists
5366: Not Collective
5368: Input Parameter:
5369: . snes - iterative context obtained from SNESCreate()
5371: Output Parameter:
5372: . has_npc - whether the SNES has an NPC or not
5374: Level: developer
5376: .keywords: SNES, has, preconditioner
5377: .seealso: SNESSetNPC(), SNESGetNPC()
5378: @*/
5379: PetscErrorCode SNESHasNPC(SNES snes, PetscBool *has_npc)
5380: {
5383: *has_npc = (PetscBool) (snes->npc ? PETSC_TRUE : PETSC_FALSE);
5384: return(0);
5385: }
5387: /*@
5388: SNESSetNPCSide - Sets the preconditioning side.
5390: Logically Collective on SNES
5392: Input Parameter:
5393: . snes - iterative context obtained from SNESCreate()
5395: Output Parameter:
5396: . side - the preconditioning side, where side is one of
5397: .vb
5398: PC_LEFT - left preconditioning
5399: PC_RIGHT - right preconditioning (default for most nonlinear solvers)
5400: .ve
5402: Options Database Keys:
5403: . -snes_pc_side <right,left>
5405: Notes:
5406: SNESNRICHARDSON and SNESNCG only support left preconditioning.
5408: Level: intermediate
5410: .keywords: SNES, set, right, left, side, preconditioner, flag
5412: .seealso: SNESGetNPCSide(), KSPSetPCSide()
5413: @*/
5414: PetscErrorCode SNESSetNPCSide(SNES snes,PCSide side)
5415: {
5419: snes->npcside= side;
5420: return(0);
5421: }
5423: /*@
5424: SNESGetNPCSide - Gets the preconditioning side.
5426: Not Collective
5428: Input Parameter:
5429: . snes - iterative context obtained from SNESCreate()
5431: Output Parameter:
5432: . side - the preconditioning side, where side is one of
5433: .vb
5434: PC_LEFT - left preconditioning
5435: PC_RIGHT - right preconditioning (default for most nonlinear solvers)
5436: .ve
5438: Level: intermediate
5440: .keywords: SNES, get, right, left, side, preconditioner, flag
5442: .seealso: SNESSetNPCSide(), KSPGetPCSide()
5443: @*/
5444: PetscErrorCode SNESGetNPCSide(SNES snes,PCSide *side)
5445: {
5449: *side = snes->npcside;
5450: return(0);
5451: }
5453: /*@
5454: SNESSetLineSearch - Sets the linesearch on the SNES instance.
5456: Collective on SNES
5458: Input Parameters:
5459: + snes - iterative context obtained from SNESCreate()
5460: - linesearch - the linesearch object
5462: Notes:
5463: Use SNESGetLineSearch() to retrieve the preconditioner context (for example,
5464: to configure it using the API).
5466: Level: developer
5468: .keywords: SNES, set, linesearch
5469: .seealso: SNESGetLineSearch()
5470: @*/
5471: PetscErrorCode SNESSetLineSearch(SNES snes, SNESLineSearch linesearch)
5472: {
5479: PetscObjectReference((PetscObject) linesearch);
5480: SNESLineSearchDestroy(&snes->linesearch);
5482: snes->linesearch = linesearch;
5484: PetscLogObjectParent((PetscObject)snes, (PetscObject)snes->linesearch);
5485: return(0);
5486: }
5488: /*@
5489: SNESGetLineSearch - Returns a pointer to the line search context set with SNESSetLineSearch()
5490: or creates a default line search instance associated with the SNES and returns it.
5492: Not Collective
5494: Input Parameter:
5495: . snes - iterative context obtained from SNESCreate()
5497: Output Parameter:
5498: . linesearch - linesearch context
5500: Level: beginner
5502: .keywords: SNES, get, linesearch
5503: .seealso: SNESSetLineSearch(), SNESLineSearchCreate()
5504: @*/
5505: PetscErrorCode SNESGetLineSearch(SNES snes, SNESLineSearch *linesearch)
5506: {
5508: const char *optionsprefix;
5513: if (!snes->linesearch) {
5514: SNESGetOptionsPrefix(snes, &optionsprefix);
5515: SNESLineSearchCreate(PetscObjectComm((PetscObject)snes), &snes->linesearch);
5516: SNESLineSearchSetSNES(snes->linesearch, snes);
5517: SNESLineSearchAppendOptionsPrefix(snes->linesearch, optionsprefix);
5518: PetscObjectIncrementTabLevel((PetscObject) snes->linesearch, (PetscObject) snes, 1);
5519: PetscLogObjectParent((PetscObject)snes, (PetscObject)snes->linesearch);
5520: }
5521: *linesearch = snes->linesearch;
5522: return(0);
5523: }
5525: #if defined(PETSC_HAVE_MATLAB_ENGINE)
5526: #include <mex.h>
5528: typedef struct {char *funcname; mxArray *ctx;} SNESMatlabContext;
5530: /*
5531: SNESComputeFunction_Matlab - Calls the function that has been set with SNESSetFunctionMatlab().
5533: Collective on SNES
5535: Input Parameters:
5536: + snes - the SNES context
5537: - x - input vector
5539: Output Parameter:
5540: . y - function vector, as set by SNESSetFunction()
5542: Notes:
5543: SNESComputeFunction() is typically used within nonlinear solvers
5544: implementations, so most users would not generally call this routine
5545: themselves.
5547: Level: developer
5549: .keywords: SNES, nonlinear, compute, function
5551: .seealso: SNESSetFunction(), SNESGetFunction()
5552: */
5553: PetscErrorCode SNESComputeFunction_Matlab(SNES snes,Vec x,Vec y, void *ctx)
5554: {
5555: PetscErrorCode ierr;
5556: SNESMatlabContext *sctx = (SNESMatlabContext*)ctx;
5557: int nlhs = 1,nrhs = 5;
5558: mxArray *plhs[1],*prhs[5];
5559: long long int lx = 0,ly = 0,ls = 0;
5568: /* call Matlab function in ctx with arguments x and y */
5570: PetscMemcpy(&ls,&snes,sizeof(snes));
5571: PetscMemcpy(&lx,&x,sizeof(x));
5572: PetscMemcpy(&ly,&y,sizeof(x));
5573: prhs[0] = mxCreateDoubleScalar((double)ls);
5574: prhs[1] = mxCreateDoubleScalar((double)lx);
5575: prhs[2] = mxCreateDoubleScalar((double)ly);
5576: prhs[3] = mxCreateString(sctx->funcname);
5577: prhs[4] = sctx->ctx;
5578: mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscSNESComputeFunctionInternal");
5579: mxGetScalar(plhs[0]);
5580: mxDestroyArray(prhs[0]);
5581: mxDestroyArray(prhs[1]);
5582: mxDestroyArray(prhs[2]);
5583: mxDestroyArray(prhs[3]);
5584: mxDestroyArray(plhs[0]);
5585: return(0);
5586: }
5588: /*
5589: SNESSetFunctionMatlab - Sets the function evaluation routine and function
5590: vector for use by the SNES routines in solving systems of nonlinear
5591: equations from MATLAB. Here the function is a string containing the name of a MATLAB function
5593: Logically Collective on SNES
5595: Input Parameters:
5596: + snes - the SNES context
5597: . r - vector to store function value
5598: - f - function evaluation routine
5600: Notes:
5601: The Newton-like methods typically solve linear systems of the form
5602: $ f'(x) x = -f(x),
5603: where f'(x) denotes the Jacobian matrix and f(x) is the function.
5605: Level: beginner
5607: Developer Note: This bleeds the allocated memory SNESMatlabContext *sctx;
5609: .keywords: SNES, nonlinear, set, function
5611: .seealso: SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESSetFunction()
5612: */
5613: PetscErrorCode SNESSetFunctionMatlab(SNES snes,Vec r,const char *f,mxArray *ctx)
5614: {
5615: PetscErrorCode ierr;
5616: SNESMatlabContext *sctx;
5619: /* currently sctx is memory bleed */
5620: PetscNew(&sctx);
5621: PetscStrallocpy(f,&sctx->funcname);
5622: /*
5623: This should work, but it doesn't
5624: sctx->ctx = ctx;
5625: mexMakeArrayPersistent(sctx->ctx);
5626: */
5627: sctx->ctx = mxDuplicateArray(ctx);
5628: SNESSetFunction(snes,r,SNESComputeFunction_Matlab,sctx);
5629: return(0);
5630: }
5632: /*
5633: SNESComputeJacobian_Matlab - Calls the function that has been set with SNESSetJacobianMatlab().
5635: Collective on SNES
5637: Input Parameters:
5638: + snes - the SNES context
5639: . x - input vector
5640: . A, B - the matrices
5641: - ctx - user context
5643: Level: developer
5645: .keywords: SNES, nonlinear, compute, function
5647: .seealso: SNESSetFunction(), SNESGetFunction()
5648: @*/
5649: PetscErrorCode SNESComputeJacobian_Matlab(SNES snes,Vec x,Mat A,Mat B,void *ctx)
5650: {
5651: PetscErrorCode ierr;
5652: SNESMatlabContext *sctx = (SNESMatlabContext*)ctx;
5653: int nlhs = 2,nrhs = 6;
5654: mxArray *plhs[2],*prhs[6];
5655: long long int lx = 0,lA = 0,ls = 0, lB = 0;
5661: /* call Matlab function in ctx with arguments x and y */
5663: PetscMemcpy(&ls,&snes,sizeof(snes));
5664: PetscMemcpy(&lx,&x,sizeof(x));
5665: PetscMemcpy(&lA,A,sizeof(x));
5666: PetscMemcpy(&lB,B,sizeof(x));
5667: prhs[0] = mxCreateDoubleScalar((double)ls);
5668: prhs[1] = mxCreateDoubleScalar((double)lx);
5669: prhs[2] = mxCreateDoubleScalar((double)lA);
5670: prhs[3] = mxCreateDoubleScalar((double)lB);
5671: prhs[4] = mxCreateString(sctx->funcname);
5672: prhs[5] = sctx->ctx;
5673: mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscSNESComputeJacobianInternal");
5674: mxGetScalar(plhs[0]);
5675: mxDestroyArray(prhs[0]);
5676: mxDestroyArray(prhs[1]);
5677: mxDestroyArray(prhs[2]);
5678: mxDestroyArray(prhs[3]);
5679: mxDestroyArray(prhs[4]);
5680: mxDestroyArray(plhs[0]);
5681: mxDestroyArray(plhs[1]);
5682: return(0);
5683: }
5685: /*
5686: SNESSetJacobianMatlab - Sets the Jacobian function evaluation routine and two empty Jacobian matrices
5687: vector for use by the SNES routines in solving systems of nonlinear
5688: equations from MATLAB. Here the function is a string containing the name of a MATLAB function
5690: Logically Collective on SNES
5692: Input Parameters:
5693: + snes - the SNES context
5694: . A,B - Jacobian matrices
5695: . J - function evaluation routine
5696: - ctx - user context
5698: Level: developer
5700: Developer Note: This bleeds the allocated memory SNESMatlabContext *sctx;
5702: .keywords: SNES, nonlinear, set, function
5704: .seealso: SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESSetFunction(), J
5705: */
5706: PetscErrorCode SNESSetJacobianMatlab(SNES snes,Mat A,Mat B,const char *J,mxArray *ctx)
5707: {
5708: PetscErrorCode ierr;
5709: SNESMatlabContext *sctx;
5712: /* currently sctx is memory bleed */
5713: PetscNew(&sctx);
5714: PetscStrallocpy(J,&sctx->funcname);
5715: /*
5716: This should work, but it doesn't
5717: sctx->ctx = ctx;
5718: mexMakeArrayPersistent(sctx->ctx);
5719: */
5720: sctx->ctx = mxDuplicateArray(ctx);
5721: SNESSetJacobian(snes,A,B,SNESComputeJacobian_Matlab,sctx);
5722: return(0);
5723: }
5725: /*
5726: SNESMonitor_Matlab - Calls the function that has been set with SNESMonitorSetMatlab().
5728: Collective on SNES
5730: .seealso: SNESSetFunction(), SNESGetFunction()
5731: @*/
5732: PetscErrorCode SNESMonitor_Matlab(SNES snes,PetscInt it, PetscReal fnorm, void *ctx)
5733: {
5734: PetscErrorCode ierr;
5735: SNESMatlabContext *sctx = (SNESMatlabContext*)ctx;
5736: int nlhs = 1,nrhs = 6;
5737: mxArray *plhs[1],*prhs[6];
5738: long long int lx = 0,ls = 0;
5739: Vec x = snes->vec_sol;
5744: PetscMemcpy(&ls,&snes,sizeof(snes));
5745: PetscMemcpy(&lx,&x,sizeof(x));
5746: prhs[0] = mxCreateDoubleScalar((double)ls);
5747: prhs[1] = mxCreateDoubleScalar((double)it);
5748: prhs[2] = mxCreateDoubleScalar((double)fnorm);
5749: prhs[3] = mxCreateDoubleScalar((double)lx);
5750: prhs[4] = mxCreateString(sctx->funcname);
5751: prhs[5] = sctx->ctx;
5752: mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscSNESMonitorInternal");
5753: mxGetScalar(plhs[0]);
5754: mxDestroyArray(prhs[0]);
5755: mxDestroyArray(prhs[1]);
5756: mxDestroyArray(prhs[2]);
5757: mxDestroyArray(prhs[3]);
5758: mxDestroyArray(prhs[4]);
5759: mxDestroyArray(plhs[0]);
5760: return(0);
5761: }
5763: /*
5764: SNESMonitorSetMatlab - Sets the monitor function from MATLAB
5766: Level: developer
5768: Developer Note: This bleeds the allocated memory SNESMatlabContext *sctx;
5770: .keywords: SNES, nonlinear, set, function
5772: .seealso: SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESSetFunction()
5773: */
5774: PetscErrorCode SNESMonitorSetMatlab(SNES snes,const char *f,mxArray *ctx)
5775: {
5776: PetscErrorCode ierr;
5777: SNESMatlabContext *sctx;
5780: /* currently sctx is memory bleed */
5781: PetscNew(&sctx);
5782: PetscStrallocpy(f,&sctx->funcname);
5783: /*
5784: This should work, but it doesn't
5785: sctx->ctx = ctx;
5786: mexMakeArrayPersistent(sctx->ctx);
5787: */
5788: sctx->ctx = mxDuplicateArray(ctx);
5789: SNESMonitorSet(snes,SNESMonitor_Matlab,sctx,NULL);
5790: return(0);
5791: }
5793: #endif