Actual source code: snes.c
petsc-3.8.0 2017-09-26
2: #include <petsc/private/snesimpl.h>
3: #include <petscdmshell.h>
4: #include <petscdraw.h>
5: #include <petscds.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
227: /*@C
228: SNESView - Prints the SNES data structure.
230: Collective on SNES
232: Input Parameters:
233: + SNES - the SNES context
234: - viewer - visualization context
236: Options Database Key:
237: . -snes_view - Calls SNESView() at end of SNESSolve()
239: Notes:
240: The available visualization contexts include
241: + PETSC_VIEWER_STDOUT_SELF - standard output (default)
242: - PETSC_VIEWER_STDOUT_WORLD - synchronized standard
243: output where only the first processor opens
244: the file. All other processors send their
245: data to the first processor to print.
247: The user can open an alternative visualization context with
248: PetscViewerASCIIOpen() - output to a specified file.
250: Level: beginner
252: .keywords: SNES, view
254: .seealso: PetscViewerASCIIOpen()
255: @*/
256: PetscErrorCode SNESView(SNES snes,PetscViewer viewer)
257: {
258: SNESKSPEW *kctx;
260: KSP ksp;
261: SNESLineSearch linesearch;
262: PetscBool iascii,isstring,isbinary,isdraw;
263: DMSNES dmsnes;
264: #if defined(PETSC_HAVE_SAWS)
265: PetscBool issaws;
266: #endif
270: if (!viewer) {
271: PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)snes),&viewer);
272: }
276: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);
277: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSTRING,&isstring);
278: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);
279: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);
280: #if defined(PETSC_HAVE_SAWS)
281: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSAWS,&issaws);
282: #endif
283: if (iascii) {
284: SNESNormSchedule normschedule;
286: PetscObjectPrintClassNamePrefixType((PetscObject)snes,viewer);
287: if (!snes->setupcalled) {
288: PetscViewerASCIIPrintf(viewer," SNES has not been set up so information may be incomplete\n");
289: }
290: if (snes->ops->view) {
291: PetscViewerASCIIPushTab(viewer);
292: (*snes->ops->view)(snes,viewer);
293: PetscViewerASCIIPopTab(viewer);
294: }
295: PetscViewerASCIIPrintf(viewer," maximum iterations=%D, maximum function evaluations=%D\n",snes->max_its,snes->max_funcs);
296: PetscViewerASCIIPrintf(viewer," tolerances: relative=%g, absolute=%g, solution=%g\n",(double)snes->rtol,(double)snes->abstol,(double)snes->stol);
297: if (snes->usesksp) {
298: PetscViewerASCIIPrintf(viewer," total number of linear solver iterations=%D\n",snes->linear_its);
299: }
300: PetscViewerASCIIPrintf(viewer," total number of function evaluations=%D\n",snes->nfuncs);
301: SNESGetNormSchedule(snes, &normschedule);
302: if (normschedule > 0) {PetscViewerASCIIPrintf(viewer," norm schedule %s\n",SNESNormSchedules[normschedule]);}
303: if (snes->gridsequence) {
304: PetscViewerASCIIPrintf(viewer," total number of grid sequence refinements=%D\n",snes->gridsequence);
305: }
306: if (snes->ksp_ewconv) {
307: kctx = (SNESKSPEW*)snes->kspconvctx;
308: if (kctx) {
309: PetscViewerASCIIPrintf(viewer," Eisenstat-Walker computation of KSP relative tolerance (version %D)\n",kctx->version);
310: PetscViewerASCIIPrintf(viewer," rtol_0=%g, rtol_max=%g, threshold=%g\n",(double)kctx->rtol_0,(double)kctx->rtol_max,(double)kctx->threshold);
311: PetscViewerASCIIPrintf(viewer," gamma=%g, alpha=%g, alpha2=%g\n",(double)kctx->gamma,(double)kctx->alpha,(double)kctx->alpha2);
312: }
313: }
314: if (snes->lagpreconditioner == -1) {
315: PetscViewerASCIIPrintf(viewer," Preconditioned is never rebuilt\n");
316: } else if (snes->lagpreconditioner > 1) {
317: PetscViewerASCIIPrintf(viewer," Preconditioned is rebuilt every %D new Jacobians\n",snes->lagpreconditioner);
318: }
319: if (snes->lagjacobian == -1) {
320: PetscViewerASCIIPrintf(viewer," Jacobian is never rebuilt\n");
321: } else if (snes->lagjacobian > 1) {
322: PetscViewerASCIIPrintf(viewer," Jacobian is rebuilt every %D SNES iterations\n",snes->lagjacobian);
323: }
324: } else if (isstring) {
325: const char *type;
326: SNESGetType(snes,&type);
327: PetscViewerStringSPrintf(viewer," %-3.3s",type);
328: } else if (isbinary) {
329: PetscInt classid = SNES_FILE_CLASSID;
330: MPI_Comm comm;
331: PetscMPIInt rank;
332: char type[256];
334: PetscObjectGetComm((PetscObject)snes,&comm);
335: MPI_Comm_rank(comm,&rank);
336: if (!rank) {
337: PetscViewerBinaryWrite(viewer,&classid,1,PETSC_INT,PETSC_FALSE);
338: PetscStrncpy(type,((PetscObject)snes)->type_name,sizeof(type));
339: PetscViewerBinaryWrite(viewer,type,sizeof(type),PETSC_CHAR,PETSC_FALSE);
340: }
341: if (snes->ops->view) {
342: (*snes->ops->view)(snes,viewer);
343: }
344: } else if (isdraw) {
345: PetscDraw draw;
346: char str[36];
347: PetscReal x,y,bottom,h;
349: PetscViewerDrawGetDraw(viewer,0,&draw);
350: PetscDrawGetCurrentPoint(draw,&x,&y);
351: PetscStrcpy(str,"SNES: ");
352: PetscStrcat(str,((PetscObject)snes)->type_name);
353: PetscDrawStringBoxed(draw,x,y,PETSC_DRAW_BLUE,PETSC_DRAW_BLACK,str,NULL,&h);
354: bottom = y - h;
355: PetscDrawPushCurrentPoint(draw,x,bottom);
356: if (snes->ops->view) {
357: (*snes->ops->view)(snes,viewer);
358: }
359: #if defined(PETSC_HAVE_SAWS)
360: } else if (issaws) {
361: PetscMPIInt rank;
362: const char *name;
364: PetscObjectGetName((PetscObject)snes,&name);
365: MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
366: if (!((PetscObject)snes)->amsmem && !rank) {
367: char dir[1024];
369: PetscObjectViewSAWs((PetscObject)snes,viewer);
370: PetscSNPrintf(dir,1024,"/PETSc/Objects/%s/its",name);
371: PetscStackCallSAWs(SAWs_Register,(dir,&snes->iter,1,SAWs_READ,SAWs_INT));
372: if (!snes->conv_hist) {
373: SNESSetConvergenceHistory(snes,NULL,NULL,PETSC_DECIDE,PETSC_TRUE);
374: }
375: PetscSNPrintf(dir,1024,"/PETSc/Objects/%s/conv_hist",name);
376: PetscStackCallSAWs(SAWs_Register,(dir,snes->conv_hist,10,SAWs_READ,SAWs_DOUBLE));
377: }
378: #endif
379: }
380: if (snes->linesearch) {
381: PetscViewerASCIIPushTab(viewer);
382: SNESGetLineSearch(snes, &linesearch);
383: SNESLineSearchView(linesearch, viewer);
384: PetscViewerASCIIPopTab(viewer);
385: }
386: if (snes->npc && snes->usesnpc) {
387: PetscViewerASCIIPushTab(viewer);
388: SNESView(snes->npc, viewer);
389: PetscViewerASCIIPopTab(viewer);
390: }
391: PetscViewerASCIIPushTab(viewer);
392: DMGetDMSNES(snes->dm,&dmsnes);
393: DMSNESView(dmsnes, viewer);
394: PetscViewerASCIIPopTab(viewer);
395: if (snes->usesksp) {
396: SNESGetKSP(snes,&ksp);
397: PetscViewerASCIIPushTab(viewer);
398: KSPView(ksp,viewer);
399: PetscViewerASCIIPopTab(viewer);
400: }
401: if (isdraw) {
402: PetscDraw draw;
403: PetscViewerDrawGetDraw(viewer,0,&draw);
404: PetscDrawPopCurrentPoint(draw);
405: }
406: return(0);
407: }
409: /*
410: We retain a list of functions that also take SNES command
411: line options. These are called at the end SNESSetFromOptions()
412: */
413: #define MAXSETFROMOPTIONS 5
414: static PetscInt numberofsetfromoptions;
415: static PetscErrorCode (*othersetfromoptions[MAXSETFROMOPTIONS])(SNES);
417: /*@C
418: SNESAddOptionsChecker - Adds an additional function to check for SNES options.
420: Not Collective
422: Input Parameter:
423: . snescheck - function that checks for options
425: Level: developer
427: .seealso: SNESSetFromOptions()
428: @*/
429: PetscErrorCode SNESAddOptionsChecker(PetscErrorCode (*snescheck)(SNES))
430: {
432: if (numberofsetfromoptions >= MAXSETFROMOPTIONS) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE, "Too many options checkers, only %D allowed", MAXSETFROMOPTIONS);
433: othersetfromoptions[numberofsetfromoptions++] = snescheck;
434: return(0);
435: }
437: extern PetscErrorCode SNESDefaultMatrixFreeCreate2(SNES,Vec,Mat*);
439: static PetscErrorCode SNESSetUpMatrixFree_Private(SNES snes, PetscBool hasOperator, PetscInt version)
440: {
441: Mat J;
442: KSP ksp;
443: PC pc;
444: PetscBool match;
446: MatNullSpace nullsp;
451: if (!snes->vec_func && (snes->jacobian || snes->jacobian_pre)) {
452: Mat A = snes->jacobian, B = snes->jacobian_pre;
453: MatCreateVecs(A ? A : B, NULL,&snes->vec_func);
454: }
456: if (version == 1) {
457: MatCreateSNESMF(snes,&J);
458: MatMFFDSetOptionsPrefix(J,((PetscObject)snes)->prefix);
459: MatSetFromOptions(J);
460: } else if (version == 2) {
461: if (!snes->vec_func) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"SNESSetFunction() must be called first");
462: #if !defined(PETSC_USE_COMPLEX) && !defined(PETSC_USE_REAL_SINGLE) && !defined(PETSC_USE_REAL___FLOAT128) && !defined(PETSC_USE_REAL___FP16)
463: SNESDefaultMatrixFreeCreate2(snes,snes->vec_func,&J);
464: #else
465: SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP, "matrix-free operator rutines (version 2)");
466: #endif
467: } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE, "matrix-free operator rutines, only version 1 and 2");
469: /* attach any user provided null space that was on Amat to the newly created matrix free matrix */
470: if (snes->jacobian) {
471: MatGetNullSpace(snes->jacobian,&nullsp);
472: if (nullsp) {
473: MatSetNullSpace(J,nullsp);
474: }
475: }
477: PetscInfo1(snes,"Setting default matrix-free operator routines (version %D)\n", version);
478: if (hasOperator) {
480: /* This version replaces the user provided Jacobian matrix with a
481: matrix-free version but still employs the user-provided preconditioner matrix. */
482: SNESSetJacobian(snes,J,0,0,0);
483: } else {
484: /* This version replaces both the user-provided Jacobian and the user-
485: provided preconditioner Jacobian with the default matrix free version. */
486: if ((snes->npcside== PC_LEFT) && snes->npc) {
487: if (!snes->jacobian){SNESSetJacobian(snes,J,0,0,0);}
488: } else {
489: SNESSetJacobian(snes,J,J,MatMFFDComputeJacobian,0);
490: }
491: /* Force no preconditioner */
492: SNESGetKSP(snes,&ksp);
493: KSPGetPC(ksp,&pc);
494: PetscObjectTypeCompare((PetscObject)pc,PCSHELL,&match);
495: if (!match) {
496: PetscInfo(snes,"Setting default matrix-free preconditioner routines\nThat is no preconditioner is being used\n");
497: PCSetType(pc,PCNONE);
498: }
499: }
500: MatDestroy(&J);
501: return(0);
502: }
504: static PetscErrorCode DMRestrictHook_SNESVecSol(DM dmfine,Mat Restrict,Vec Rscale,Mat Inject,DM dmcoarse,void *ctx)
505: {
506: SNES snes = (SNES)ctx;
508: Vec Xfine,Xfine_named = NULL,Xcoarse;
511: if (PetscLogPrintInfo) {
512: PetscInt finelevel,coarselevel,fineclevel,coarseclevel;
513: DMGetRefineLevel(dmfine,&finelevel);
514: DMGetCoarsenLevel(dmfine,&fineclevel);
515: DMGetRefineLevel(dmcoarse,&coarselevel);
516: DMGetCoarsenLevel(dmcoarse,&coarseclevel);
517: PetscInfo4(dmfine,"Restricting SNES solution vector from level %D-%D to level %D-%D\n",finelevel,fineclevel,coarselevel,coarseclevel);
518: }
519: if (dmfine == snes->dm) Xfine = snes->vec_sol;
520: else {
521: DMGetNamedGlobalVector(dmfine,"SNESVecSol",&Xfine_named);
522: Xfine = Xfine_named;
523: }
524: DMGetNamedGlobalVector(dmcoarse,"SNESVecSol",&Xcoarse);
525: if (Inject) {
526: MatRestrict(Inject,Xfine,Xcoarse);
527: } else {
528: MatRestrict(Restrict,Xfine,Xcoarse);
529: VecPointwiseMult(Xcoarse,Xcoarse,Rscale);
530: }
531: DMRestoreNamedGlobalVector(dmcoarse,"SNESVecSol",&Xcoarse);
532: if (Xfine_named) {DMRestoreNamedGlobalVector(dmfine,"SNESVecSol",&Xfine_named);}
533: return(0);
534: }
536: static PetscErrorCode DMCoarsenHook_SNESVecSol(DM dm,DM dmc,void *ctx)
537: {
541: DMCoarsenHookAdd(dmc,DMCoarsenHook_SNESVecSol,DMRestrictHook_SNESVecSol,ctx);
542: return(0);
543: }
545: /* This may be called to rediscretize the operator on levels of linear multigrid. The DM shuffle is so the user can
546: * safely call SNESGetDM() in their residual evaluation routine. */
547: static PetscErrorCode KSPComputeOperators_SNES(KSP ksp,Mat A,Mat B,void *ctx)
548: {
549: SNES snes = (SNES)ctx;
551: Mat Asave = A,Bsave = B;
552: Vec X,Xnamed = NULL;
553: DM dmsave;
554: void *ctxsave;
555: PetscErrorCode (*jac)(SNES,Vec,Mat,Mat,void*);
558: dmsave = snes->dm;
559: KSPGetDM(ksp,&snes->dm);
560: if (dmsave == snes->dm) X = snes->vec_sol; /* We are on the finest level */
561: else { /* We are on a coarser level, this vec was initialized using a DM restrict hook */
562: DMGetNamedGlobalVector(snes->dm,"SNESVecSol",&Xnamed);
563: X = Xnamed;
564: SNESGetJacobian(snes,NULL,NULL,&jac,&ctxsave);
565: /* If the DM's don't match up, the MatFDColoring context needed for the jacobian won't match up either -- fixit. */
566: if (jac == SNESComputeJacobianDefaultColor) {
567: SNESSetJacobian(snes,NULL,NULL,SNESComputeJacobianDefaultColor,0);
568: }
569: }
570: /* put the previous context back */
572: SNESComputeJacobian(snes,X,A,B);
573: if (snes->dm != dmsave && jac == SNESComputeJacobianDefaultColor) {
574: SNESSetJacobian(snes,NULL,NULL,jac,ctxsave);
575: }
577: if (A != Asave || B != Bsave) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_SUP,"No support for changing matrices at this time");
578: if (Xnamed) {
579: DMRestoreNamedGlobalVector(snes->dm,"SNESVecSol",&Xnamed);
580: }
581: snes->dm = dmsave;
582: return(0);
583: }
585: /*@
586: SNESSetUpMatrices - ensures that matrices are available for SNES, to be called by SNESSetUp_XXX()
588: Collective
590: Input Arguments:
591: . snes - snes to configure
593: Level: developer
595: .seealso: SNESSetUp()
596: @*/
597: PetscErrorCode SNESSetUpMatrices(SNES snes)
598: {
600: DM dm;
601: DMSNES sdm;
604: SNESGetDM(snes,&dm);
605: DMGetDMSNES(dm,&sdm);
606: if (!sdm->ops->computejacobian) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_PLIB,"DMSNES not properly configured");
607: else if (!snes->jacobian && snes->mf) {
608: Mat J;
609: void *functx;
610: MatCreateSNESMF(snes,&J);
611: MatMFFDSetOptionsPrefix(J,((PetscObject)snes)->prefix);
612: MatSetFromOptions(J);
613: SNESGetFunction(snes,NULL,NULL,&functx);
614: SNESSetJacobian(snes,J,J,0,0);
615: MatDestroy(&J);
616: } else if (snes->mf_operator && !snes->jacobian_pre && !snes->jacobian) {
617: Mat J,B;
618: MatCreateSNESMF(snes,&J);
619: MatMFFDSetOptionsPrefix(J,((PetscObject)snes)->prefix);
620: MatSetFromOptions(J);
621: DMCreateMatrix(snes->dm,&B);
622: /* sdm->computejacobian was already set to reach here */
623: SNESSetJacobian(snes,J,B,NULL,NULL);
624: MatDestroy(&J);
625: MatDestroy(&B);
626: } else if (!snes->jacobian_pre) {
627: PetscDS prob;
628: Mat J, B;
629: PetscBool hasPrec = PETSC_FALSE;
631: J = snes->jacobian;
632: DMGetDS(dm, &prob);
633: if (prob) {PetscDSHasJacobianPreconditioner(prob, &hasPrec);}
634: if (J) {PetscObjectReference((PetscObject) J);}
635: else if (hasPrec) {DMCreateMatrix(snes->dm, &J);}
636: DMCreateMatrix(snes->dm, &B);
637: SNESSetJacobian(snes, J ? J : B, B, NULL, NULL);
638: MatDestroy(&J);
639: MatDestroy(&B);
640: }
641: {
642: KSP ksp;
643: SNESGetKSP(snes,&ksp);
644: KSPSetComputeOperators(ksp,KSPComputeOperators_SNES,snes);
645: DMCoarsenHookAdd(snes->dm,DMCoarsenHook_SNESVecSol,DMRestrictHook_SNESVecSol,snes);
646: }
647: return(0);
648: }
650: /*@C
651: SNESMonitorSetFromOptions - Sets a monitor function and viewer appropriate for the type indicated by the user
653: Collective on SNES
655: Input Parameters:
656: + snes - SNES object you wish to monitor
657: . name - the monitor type one is seeking
658: . help - message indicating what monitoring is done
659: . manual - manual page for the monitor
660: . monitor - the monitor function
661: - 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
663: Level: developer
665: .seealso: PetscOptionsGetViewer(), PetscOptionsGetReal(), PetscOptionsHasName(), PetscOptionsGetString(),
666: PetscOptionsGetIntArray(), PetscOptionsGetRealArray(), PetscOptionsBool()
667: PetscOptionsInt(), PetscOptionsString(), PetscOptionsReal(), PetscOptionsBool(),
668: PetscOptionsName(), PetscOptionsBegin(), PetscOptionsEnd(), PetscOptionsHead(),
669: PetscOptionsStringArray(),PetscOptionsRealArray(), PetscOptionsScalar(),
670: PetscOptionsBoolGroupBegin(), PetscOptionsBoolGroup(), PetscOptionsBoolGroupEnd(),
671: PetscOptionsFList(), PetscOptionsEList()
672: @*/
673: PetscErrorCode SNESMonitorSetFromOptions(SNES snes,const char name[],const char help[], const char manual[],PetscErrorCode (*monitor)(SNES,PetscInt,PetscReal,PetscViewerAndFormat*),PetscErrorCode (*monitorsetup)(SNES,PetscViewerAndFormat*))
674: {
675: PetscErrorCode ierr;
676: PetscViewer viewer;
677: PetscViewerFormat format;
678: PetscBool flg;
681: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,name,&viewer,&format,&flg);
682: if (flg) {
683: PetscViewerAndFormat *vf;
684: PetscViewerAndFormatCreate(viewer,format,&vf);
685: PetscObjectDereference((PetscObject)viewer);
686: if (monitorsetup) {
687: (*monitorsetup)(snes,vf);
688: }
689: SNESMonitorSet(snes,(PetscErrorCode (*)(SNES,PetscInt,PetscReal,void*))monitor,vf,(PetscErrorCode (*)(void**))PetscViewerAndFormatDestroy);
690: }
691: return(0);
692: }
694: /*@
695: SNESSetFromOptions - Sets various SNES and KSP parameters from user options.
697: Collective on SNES
699: Input Parameter:
700: . snes - the SNES context
702: Options Database Keys:
703: + -snes_type <type> - newtonls, newtontr, ngmres, ncg, nrichardson, qn, vi, fas, SNESType for complete list
704: . -snes_stol - convergence tolerance in terms of the norm
705: of the change in the solution between steps
706: . -snes_atol <abstol> - absolute tolerance of residual norm
707: . -snes_rtol <rtol> - relative decrease in tolerance norm from initial
708: . -snes_divergence_tolerance <divtol> - if the residual goes above divtol*rnorm0, exit with divergence
709: . -snes_force_iteration <force> - force SNESSolve() to take at least one iteration
710: . -snes_max_it <max_it> - maximum number of iterations
711: . -snes_max_funcs <max_funcs> - maximum number of function evaluations
712: . -snes_max_fail <max_fail> - maximum number of line search failures allowed before stopping, default is none
713: . -snes_max_linear_solve_fail - number of linear solver failures before SNESSolve() stops
714: . -snes_lag_preconditioner <lag> - how often preconditioner is rebuilt (use -1 to never rebuild)
715: . -snes_lag_jacobian <lag> - how often Jacobian is rebuilt (use -1 to never rebuild)
716: . -snes_trtol <trtol> - trust region tolerance
717: . -snes_no_convergence_test - skip convergence test in nonlinear
718: solver; hence iterations will continue until max_it
719: or some other criterion is reached. Saves expense
720: of convergence test
721: . -snes_monitor [ascii][:filename][:viewer format] - prints residual norm at each iteration. if no filename given prints to stdout
722: . -snes_monitor_solution [ascii binary draw][:filename][:viewer format] - plots solution at each iteration
723: . -snes_monitor_residual [ascii binary draw][:filename][:viewer format] - plots residual (not its norm) at each iteration
724: . -snes_monitor_solution_update [ascii binary draw][:filename][:viewer format] - plots update to solution at each iteration
725: . -snes_monitor_lg_residualnorm - plots residual norm at each iteration
726: . -snes_monitor_lg_range - plots residual norm at each iteration
727: . -snes_fd - use finite differences to compute Jacobian; very slow, only for testing
728: . -snes_fd_color - use finite differences with coloring to compute Jacobian
729: . -snes_mf_ksp_monitor - if using matrix-free multiply then print h at each KSP iteration
730: - -snes_converged_reason - print the reason for convergence/divergence after each solve
732: Options Database for Eisenstat-Walker method:
733: + -snes_ksp_ew - use Eisenstat-Walker method for determining linear system convergence
734: . -snes_ksp_ew_version ver - version of Eisenstat-Walker method
735: . -snes_ksp_ew_rtol0 <rtol0> - Sets rtol0
736: . -snes_ksp_ew_rtolmax <rtolmax> - Sets rtolmax
737: . -snes_ksp_ew_gamma <gamma> - Sets gamma
738: . -snes_ksp_ew_alpha <alpha> - Sets alpha
739: . -snes_ksp_ew_alpha2 <alpha2> - Sets alpha2
740: - -snes_ksp_ew_threshold <threshold> - Sets threshold
742: Notes:
743: To see all options, run your program with the -help option or consult
744: Users-Manual: ch_snes
746: Level: beginner
748: .keywords: SNES, nonlinear, set, options, database
750: .seealso: SNESSetOptionsPrefix()
751: @*/
752: PetscErrorCode SNESSetFromOptions(SNES snes)
753: {
754: PetscBool flg,pcset,persist,set;
755: PetscInt i,indx,lag,grids;
756: const char *deft = SNESNEWTONLS;
757: const char *convtests[] = {"default","skip"};
758: SNESKSPEW *kctx = NULL;
759: char type[256], monfilename[PETSC_MAX_PATH_LEN];
761: PCSide pcside;
762: const char *optionsprefix;
766: SNESRegisterAll();
767: PetscObjectOptionsBegin((PetscObject)snes);
768: if (((PetscObject)snes)->type_name) deft = ((PetscObject)snes)->type_name;
769: PetscOptionsFList("-snes_type","Nonlinear solver method","SNESSetType",SNESList,deft,type,256,&flg);
770: if (flg) {
771: SNESSetType(snes,type);
772: } else if (!((PetscObject)snes)->type_name) {
773: SNESSetType(snes,deft);
774: }
775: PetscOptionsReal("-snes_stol","Stop if step length less than","SNESSetTolerances",snes->stol,&snes->stol,NULL);
776: PetscOptionsReal("-snes_atol","Stop if function norm less than","SNESSetTolerances",snes->abstol,&snes->abstol,NULL);
778: PetscOptionsReal("-snes_rtol","Stop if decrease in function norm less than","SNESSetTolerances",snes->rtol,&snes->rtol,NULL);
779: PetscOptionsReal("-snes_divergence_tolerance","Stop if residual norm increases by this factor","SNESSetDivergenceTolerance",snes->divtol,&snes->divtol,NULL);
780: PetscOptionsInt("-snes_max_it","Maximum iterations","SNESSetTolerances",snes->max_its,&snes->max_its,NULL);
781: PetscOptionsInt("-snes_max_funcs","Maximum function evaluations","SNESSetTolerances",snes->max_funcs,&snes->max_funcs,NULL);
782: PetscOptionsInt("-snes_max_fail","Maximum nonlinear step failures","SNESSetMaxNonlinearStepFailures",snes->maxFailures,&snes->maxFailures,NULL);
783: PetscOptionsInt("-snes_max_linear_solve_fail","Maximum failures in linear solves allowed","SNESSetMaxLinearSolveFailures",snes->maxLinearSolveFailures,&snes->maxLinearSolveFailures,NULL);
784: PetscOptionsBool("-snes_error_if_not_converged","Generate error if solver does not converge","SNESSetErrorIfNotConverged",snes->errorifnotconverged,&snes->errorifnotconverged,NULL);
785: PetscOptionsBool("-snes_force_iteration","Force SNESSolve() to take at least one iteration","SNESForceIteration",snes->forceiteration,&snes->forceiteration,NULL);
787: PetscOptionsInt("-snes_lag_preconditioner","How often to rebuild preconditioner","SNESSetLagPreconditioner",snes->lagpreconditioner,&lag,&flg);
788: if (flg) {
789: SNESSetLagPreconditioner(snes,lag);
790: }
791: PetscOptionsBool("-snes_lag_preconditioner_persists","Preconditioner lagging through multiple solves","SNESSetLagPreconditionerPersists",snes->lagjac_persist,&persist,&flg);
792: if (flg) {
793: SNESSetLagPreconditionerPersists(snes,persist);
794: }
795: PetscOptionsInt("-snes_lag_jacobian","How often to rebuild Jacobian","SNESSetLagJacobian",snes->lagjacobian,&lag,&flg);
796: if (flg) {
797: SNESSetLagJacobian(snes,lag);
798: }
799: PetscOptionsBool("-snes_lag_jacobian_persists","Jacobian lagging through multiple solves","SNESSetLagJacobianPersists",snes->lagjac_persist,&persist,&flg);
800: if (flg) {
801: SNESSetLagJacobianPersists(snes,persist);
802: }
804: PetscOptionsInt("-snes_grid_sequence","Use grid sequencing to generate initial guess","SNESSetGridSequence",snes->gridsequence,&grids,&flg);
805: if (flg) {
806: SNESSetGridSequence(snes,grids);
807: }
809: PetscOptionsEList("-snes_convergence_test","Convergence test","SNESSetConvergenceTest",convtests,2,"default",&indx,&flg);
810: if (flg) {
811: switch (indx) {
812: case 0: SNESSetConvergenceTest(snes,SNESConvergedDefault,NULL,NULL); break;
813: case 1: SNESSetConvergenceTest(snes,SNESConvergedSkip,NULL,NULL); break;
814: }
815: }
817: PetscOptionsEList("-snes_norm_schedule","SNES Norm schedule","SNESSetNormSchedule",SNESNormSchedules,5,"function",&indx,&flg);
818: if (flg) { SNESSetNormSchedule(snes,(SNESNormSchedule)indx); }
820: PetscOptionsEList("-snes_function_type","SNES Norm schedule","SNESSetFunctionType",SNESFunctionTypes,2,"unpreconditioned",&indx,&flg);
821: if (flg) { SNESSetFunctionType(snes,(SNESFunctionType)indx); }
823: kctx = (SNESKSPEW*)snes->kspconvctx;
825: PetscOptionsBool("-snes_ksp_ew","Use Eisentat-Walker linear system convergence test","SNESKSPSetUseEW",snes->ksp_ewconv,&snes->ksp_ewconv,NULL);
827: PetscOptionsInt("-snes_ksp_ew_version","Version 1, 2 or 3","SNESKSPSetParametersEW",kctx->version,&kctx->version,NULL);
828: PetscOptionsReal("-snes_ksp_ew_rtol0","0 <= rtol0 < 1","SNESKSPSetParametersEW",kctx->rtol_0,&kctx->rtol_0,NULL);
829: PetscOptionsReal("-snes_ksp_ew_rtolmax","0 <= rtolmax < 1","SNESKSPSetParametersEW",kctx->rtol_max,&kctx->rtol_max,NULL);
830: PetscOptionsReal("-snes_ksp_ew_gamma","0 <= gamma <= 1","SNESKSPSetParametersEW",kctx->gamma,&kctx->gamma,NULL);
831: PetscOptionsReal("-snes_ksp_ew_alpha","1 < alpha <= 2","SNESKSPSetParametersEW",kctx->alpha,&kctx->alpha,NULL);
832: PetscOptionsReal("-snes_ksp_ew_alpha2","alpha2","SNESKSPSetParametersEW",kctx->alpha2,&kctx->alpha2,NULL);
833: PetscOptionsReal("-snes_ksp_ew_threshold","0 < threshold < 1","SNESKSPSetParametersEW",kctx->threshold,&kctx->threshold,NULL);
835: flg = PETSC_FALSE;
836: PetscOptionsBool("-snes_check_jacobian","Check each Jacobian with a differenced one","SNESUpdateCheckJacobian",flg,&flg,&set);
837: if (set && flg) {
838: SNESSetUpdate(snes,SNESUpdateCheckJacobian);
839: }
841: flg = PETSC_FALSE;
842: PetscOptionsBool("-snes_monitor_cancel","Remove all monitors","SNESMonitorCancel",flg,&flg,&set);
843: if (set && flg) {SNESMonitorCancel(snes);}
845: SNESMonitorSetFromOptions(snes,"-snes_monitor","Monitor norm of function","SNESMonitorDefault",SNESMonitorDefault,NULL);
846: SNESMonitorSetFromOptions(snes,"-snes_monitor_short","Monitor norm of function with fewer digits","SNESMonitorDefaultShort",SNESMonitorDefaultShort,NULL);
847: SNESMonitorSetFromOptions(snes,"-snes_monitor_range","Monitor range of elements of function","SNESMonitorRange",SNESMonitorRange,NULL);
849: SNESMonitorSetFromOptions(snes,"-snes_monitor_ratio","Monitor ratios of the norm of function for consecutive steps","SNESMonitorRatio",SNESMonitorRatio,SNESMonitorRatioSetUp);
850: SNESMonitorSetFromOptions(snes,"-snes_monitor_field","Monitor norm of function (split into fields)","SNESMonitorDefaultField",SNESMonitorDefaultField,NULL);
851: SNESMonitorSetFromOptions(snes,"-snes_monitor_solution","View solution at each iteration","SNESMonitorSolution",SNESMonitorSolution,NULL);
852: SNESMonitorSetFromOptions(snes,"-snes_monitor_solution_update","View correction at each iteration","SNESMonitorSolutionUpdate",SNESMonitorSolutionUpdate,NULL);
853: SNESMonitorSetFromOptions(snes,"-snes_monitor_residual","View residual at each iteration","SNESMonitorResidual",SNESMonitorResidual,NULL);
854: SNESMonitorSetFromOptions(snes,"-snes_monitor_jacupdate_spectrum","Print the change in the spectrum of the Jacobian","SNESMonitorJacUpdateSpectrum",SNESMonitorJacUpdateSpectrum,NULL);
855: SNESMonitorSetFromOptions(snes,"-snes_monitor_fields","Monitor norm of function per field","SNESMonitorSet",SNESMonitorFields,NULL);
857: PetscOptionsString("-snes_monitor_python","Use Python function","SNESMonitorSet",0,monfilename,PETSC_MAX_PATH_LEN,&flg);
858: if (flg) {PetscPythonMonitorSet((PetscObject)snes,monfilename);}
861: flg = PETSC_FALSE;
862: PetscOptionsBool("-snes_monitor_lg_residualnorm","Plot function norm at each iteration","SNESMonitorLGResidualNorm",flg,&flg,NULL);
863: if (flg) {
864: PetscDrawLG ctx;
866: SNESMonitorLGCreate(PetscObjectComm((PetscObject)snes),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,400,300,&ctx);
867: SNESMonitorSet(snes,SNESMonitorLGResidualNorm,ctx,(PetscErrorCode (*)(void**))PetscDrawLGDestroy);
868: }
869: flg = PETSC_FALSE;
870: PetscOptionsBool("-snes_monitor_lg_range","Plot function range at each iteration","SNESMonitorLGRange",flg,&flg,NULL);
871: if (flg) {
872: PetscViewer ctx;
874: PetscViewerDrawOpen(PetscObjectComm((PetscObject)snes),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,400,300,&ctx);
875: SNESMonitorSet(snes,SNESMonitorLGRange,ctx,(PetscErrorCode (*)(void**))PetscViewerDestroy);
876: }
880: flg = PETSC_FALSE;
881: PetscOptionsBool("-snes_fd","Use finite differences (slow) to compute Jacobian","SNESComputeJacobianDefault",flg,&flg,NULL);
882: if (flg) {
883: void *functx;
884: DM dm;
885: DMSNES sdm;
886: SNESGetDM(snes,&dm);
887: DMGetDMSNES(dm,&sdm);
888: sdm->jacobianctx = NULL;
889: SNESGetFunction(snes,NULL,NULL,&functx);
890: SNESSetJacobian(snes,snes->jacobian,snes->jacobian_pre,SNESComputeJacobianDefault,functx);
891: PetscInfo(snes,"Setting default finite difference Jacobian matrix\n");
892: }
894: flg = PETSC_FALSE;
895: PetscOptionsBool("-snes_fd_function","Use finite differences (slow) to compute function from user objective","SNESObjectiveComputeFunctionDefaultFD",flg,&flg,NULL);
896: if (flg) {
897: SNESSetFunction(snes,NULL,SNESObjectiveComputeFunctionDefaultFD,NULL);
898: }
900: flg = PETSC_FALSE;
901: PetscOptionsBool("-snes_fd_color","Use finite differences with coloring to compute Jacobian","SNESComputeJacobianDefaultColor",flg,&flg,NULL);
902: if (flg) {
903: DM dm;
904: DMSNES sdm;
905: SNESGetDM(snes,&dm);
906: DMGetDMSNES(dm,&sdm);
907: sdm->jacobianctx = NULL;
908: SNESSetJacobian(snes,snes->jacobian,snes->jacobian_pre,SNESComputeJacobianDefaultColor,0);
909: PetscInfo(snes,"Setting default finite difference coloring Jacobian matrix\n");
910: }
912: flg = PETSC_FALSE;
913: PetscOptionsBool("-snes_mf_operator","Use a Matrix-Free Jacobian with user-provided preconditioner matrix","SNESSetUseMatrixFree",PETSC_FALSE,&snes->mf_operator,&flg);
914: if (flg && snes->mf_operator) {
915: snes->mf_operator = PETSC_TRUE;
916: snes->mf = PETSC_TRUE;
917: }
918: flg = PETSC_FALSE;
919: PetscOptionsBool("-snes_mf","Use a Matrix-Free Jacobian with no preconditioner matrix","SNESSetUseMatrixFree",PETSC_FALSE,&snes->mf,&flg);
920: if (!flg && snes->mf_operator) snes->mf = PETSC_TRUE;
921: PetscOptionsInt("-snes_mf_version","Matrix-Free routines version 1 or 2","None",snes->mf_version,&snes->mf_version,0);
923: flg = PETSC_FALSE;
924: SNESGetNPCSide(snes,&pcside);
925: PetscOptionsEnum("-snes_npc_side","SNES nonlinear preconditioner side","SNESSetNPCSide",PCSides,(PetscEnum)pcside,(PetscEnum*)&pcside,&flg);
926: if (flg) {SNESSetNPCSide(snes,pcside);}
928: #if defined(PETSC_HAVE_SAWS)
929: /*
930: Publish convergence information using SAWs
931: */
932: flg = PETSC_FALSE;
933: PetscOptionsBool("-snes_monitor_saws","Publish SNES progress using SAWs","SNESMonitorSet",flg,&flg,NULL);
934: if (flg) {
935: void *ctx;
936: SNESMonitorSAWsCreate(snes,&ctx);
937: SNESMonitorSet(snes,SNESMonitorSAWs,ctx,SNESMonitorSAWsDestroy);
938: }
939: #endif
940: #if defined(PETSC_HAVE_SAWS)
941: {
942: PetscBool set;
943: flg = PETSC_FALSE;
944: PetscOptionsBool("-snes_saws_block","Block for SAWs at end of SNESSolve","PetscObjectSAWsBlock",((PetscObject)snes)->amspublishblock,&flg,&set);
945: if (set) {
946: PetscObjectSAWsSetBlock((PetscObject)snes,flg);
947: }
948: }
949: #endif
951: for (i = 0; i < numberofsetfromoptions; i++) {
952: (*othersetfromoptions[i])(snes);
953: }
955: if (snes->ops->setfromoptions) {
956: (*snes->ops->setfromoptions)(PetscOptionsObject,snes);
957: }
959: /* process any options handlers added with PetscObjectAddOptionsHandler() */
960: PetscObjectProcessOptionsHandlers(PetscOptionsObject,(PetscObject)snes);
961: PetscOptionsEnd();
963: if (!snes->linesearch) {
964: SNESGetLineSearch(snes, &snes->linesearch);
965: }
966: SNESLineSearchSetFromOptions(snes->linesearch);
968: if (!snes->ksp) {SNESGetKSP(snes,&snes->ksp);}
969: KSPSetOperators(snes->ksp,snes->jacobian,snes->jacobian_pre);
970: KSPSetFromOptions(snes->ksp);
972: /* if someone has set the SNES NPC type, create it. */
973: SNESGetOptionsPrefix(snes, &optionsprefix);
974: PetscOptionsHasName(((PetscObject)snes)->options,optionsprefix, "-npc_snes_type", &pcset);
975: if (pcset && (!snes->npc)) {
976: SNESGetNPC(snes, &snes->npc);
977: }
978: return(0);
979: }
981: /*@C
982: SNESSetComputeApplicationContext - Sets an optional function to compute a user-defined context for
983: the nonlinear solvers.
985: Logically Collective on SNES
987: Input Parameters:
988: + snes - the SNES context
989: . compute - function to compute the context
990: - destroy - function to destroy the context
992: Level: intermediate
994: Notes:
995: This function is currently not available from Fortran.
997: .keywords: SNES, nonlinear, set, application, context
999: .seealso: SNESGetApplicationContext(), SNESSetComputeApplicationContext(), SNESGetApplicationContext()
1000: @*/
1001: PetscErrorCode SNESSetComputeApplicationContext(SNES snes,PetscErrorCode (*compute)(SNES,void**),PetscErrorCode (*destroy)(void**))
1002: {
1005: snes->ops->usercompute = compute;
1006: snes->ops->userdestroy = destroy;
1007: return(0);
1008: }
1010: /*@
1011: SNESSetApplicationContext - Sets the optional user-defined context for
1012: the nonlinear solvers.
1014: Logically Collective on SNES
1016: Input Parameters:
1017: + snes - the SNES context
1018: - usrP - optional user context
1020: Level: intermediate
1022: Fortran Notes: To use this from Fortran you must write a Fortran interface definition for this
1023: function that tells Fortran the Fortran derived data type that you are passing in as the ctx argument.
1025: .keywords: SNES, nonlinear, set, application, context
1027: .seealso: SNESGetApplicationContext()
1028: @*/
1029: PetscErrorCode SNESSetApplicationContext(SNES snes,void *usrP)
1030: {
1032: KSP ksp;
1036: SNESGetKSP(snes,&ksp);
1037: KSPSetApplicationContext(ksp,usrP);
1038: snes->user = usrP;
1039: return(0);
1040: }
1042: /*@
1043: SNESGetApplicationContext - Gets the user-defined context for the
1044: nonlinear solvers.
1046: Not Collective
1048: Input Parameter:
1049: . snes - SNES context
1051: Output Parameter:
1052: . usrP - user context
1054: Fortran Notes: To use this from Fortran you must write a Fortran interface definition for this
1055: function that tells Fortran the Fortran derived data type that you are passing in as the ctx argument.
1057: Level: intermediate
1059: .keywords: SNES, nonlinear, get, application, context
1061: .seealso: SNESSetApplicationContext()
1062: @*/
1063: PetscErrorCode SNESGetApplicationContext(SNES snes,void *usrP)
1064: {
1067: *(void**)usrP = snes->user;
1068: return(0);
1069: }
1071: /*@
1072: SNESSetUseMatrixFree - indicates that SNES should use matrix free finite difference matrix vector products internally to apply
1073: the Jacobian.
1075: Collective on SNES
1077: Input Parameters:
1078: + snes - SNES context
1079: . mf - use matrix-free for both the Amat and Pmat used by SNESSetJacobian(), both the Amat and Pmat set in SNESSetJacobian() will be ignored
1080: - mf_operator - use matrix-free only for the Amat used by SNESSetJacobian(), this means the user provided Pmat will continue to be used
1082: Options Database:
1083: + -snes_mf - use matrix free for both the mat and pmat operator
1084: - -snes_mf_operator - use matrix free only for the mat operator
1086: Level: intermediate
1088: .keywords: SNES, nonlinear, get, iteration, number,
1090: .seealso: SNESGetUseMatrixFree(), MatCreateSNESMF()
1091: @*/
1092: PetscErrorCode SNESSetUseMatrixFree(SNES snes,PetscBool mf_operator,PetscBool mf)
1093: {
1096: if (mf && !mf_operator) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_INCOMP,"If using mf must also use mf_operator");
1097: snes->mf = mf;
1098: snes->mf_operator = mf_operator;
1099: return(0);
1100: }
1102: /*@
1103: SNESGetUseMatrixFree - indicates if the SNES uses matrix free finite difference matrix vector products to apply
1104: the Jacobian.
1106: Collective on SNES
1108: Input Parameter:
1109: . snes - SNES context
1111: Output Parameters:
1112: + mf - use matrix-free for both the Amat and Pmat used by SNESSetJacobian(), both the Amat and Pmat set in SNESSetJacobian() will be ignored
1113: - mf_operator - use matrix-free only for the Amat used by SNESSetJacobian(), this means the user provided Pmat will continue to be used
1115: Options Database:
1116: + -snes_mf - use matrix free for both the mat and pmat operator
1117: - -snes_mf_operator - use matrix free only for the mat operator
1119: Level: intermediate
1121: .keywords: SNES, nonlinear, get, iteration, number,
1123: .seealso: SNESSetUseMatrixFree(), MatCreateSNESMF()
1124: @*/
1125: PetscErrorCode SNESGetUseMatrixFree(SNES snes,PetscBool *mf_operator,PetscBool *mf)
1126: {
1129: if (mf) *mf = snes->mf;
1130: if (mf_operator) *mf_operator = snes->mf_operator;
1131: return(0);
1132: }
1134: /*@
1135: SNESGetIterationNumber - Gets the number of nonlinear iterations completed
1136: at this time.
1138: Not Collective
1140: Input Parameter:
1141: . snes - SNES context
1143: Output Parameter:
1144: . iter - iteration number
1146: Notes:
1147: For example, during the computation of iteration 2 this would return 1.
1149: This is useful for using lagged Jacobians (where one does not recompute the
1150: Jacobian at each SNES iteration). For example, the code
1151: .vb
1152: SNESGetIterationNumber(snes,&it);
1153: if (!(it % 2)) {
1154: [compute Jacobian here]
1155: }
1156: .ve
1157: can be used in your ComputeJacobian() function to cause the Jacobian to be
1158: recomputed every second SNES iteration.
1160: Level: intermediate
1162: .keywords: SNES, nonlinear, get, iteration, number,
1164: .seealso: SNESGetLinearSolveIterations()
1165: @*/
1166: PetscErrorCode SNESGetIterationNumber(SNES snes,PetscInt *iter)
1167: {
1171: *iter = snes->iter;
1172: return(0);
1173: }
1175: /*@
1176: SNESSetIterationNumber - Sets the current iteration number.
1178: Not Collective
1180: Input Parameter:
1181: . snes - SNES context
1182: . iter - iteration number
1184: Level: developer
1186: .keywords: SNES, nonlinear, set, iteration, number,
1188: .seealso: SNESGetLinearSolveIterations()
1189: @*/
1190: PetscErrorCode SNESSetIterationNumber(SNES snes,PetscInt iter)
1191: {
1196: PetscObjectSAWsTakeAccess((PetscObject)snes);
1197: snes->iter = iter;
1198: PetscObjectSAWsGrantAccess((PetscObject)snes);
1199: return(0);
1200: }
1202: /*@
1203: SNESGetNonlinearStepFailures - Gets the number of unsuccessful steps
1204: attempted by the nonlinear solver.
1206: Not Collective
1208: Input Parameter:
1209: . snes - SNES context
1211: Output Parameter:
1212: . nfails - number of unsuccessful steps attempted
1214: Notes:
1215: This counter is reset to zero for each successive call to SNESSolve().
1217: Level: intermediate
1219: .keywords: SNES, nonlinear, get, number, unsuccessful, steps
1221: .seealso: SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures(), SNESGetLinearSolveFailures(),
1222: SNESSetMaxNonlinearStepFailures(), SNESGetMaxNonlinearStepFailures()
1223: @*/
1224: PetscErrorCode SNESGetNonlinearStepFailures(SNES snes,PetscInt *nfails)
1225: {
1229: *nfails = snes->numFailures;
1230: return(0);
1231: }
1233: /*@
1234: SNESSetMaxNonlinearStepFailures - Sets the maximum number of unsuccessful steps
1235: attempted by the nonlinear solver before it gives up.
1237: Not Collective
1239: Input Parameters:
1240: + snes - SNES context
1241: - maxFails - maximum of unsuccessful steps
1243: Level: intermediate
1245: .keywords: SNES, nonlinear, set, maximum, unsuccessful, steps
1247: .seealso: SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures(), SNESGetLinearSolveFailures(),
1248: SNESGetMaxNonlinearStepFailures(), SNESGetNonlinearStepFailures()
1249: @*/
1250: PetscErrorCode SNESSetMaxNonlinearStepFailures(SNES snes, PetscInt maxFails)
1251: {
1254: snes->maxFailures = maxFails;
1255: return(0);
1256: }
1258: /*@
1259: SNESGetMaxNonlinearStepFailures - Gets the maximum number of unsuccessful steps
1260: attempted by the nonlinear solver before it gives up.
1262: Not Collective
1264: Input Parameter:
1265: . snes - SNES context
1267: Output Parameter:
1268: . maxFails - maximum of unsuccessful steps
1270: Level: intermediate
1272: .keywords: SNES, nonlinear, get, maximum, unsuccessful, steps
1274: .seealso: SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures(), SNESGetLinearSolveFailures(),
1275: SNESSetMaxNonlinearStepFailures(), SNESGetNonlinearStepFailures()
1277: @*/
1278: PetscErrorCode SNESGetMaxNonlinearStepFailures(SNES snes, PetscInt *maxFails)
1279: {
1283: *maxFails = snes->maxFailures;
1284: return(0);
1285: }
1287: /*@
1288: SNESGetNumberFunctionEvals - Gets the number of user provided function evaluations
1289: done by SNES.
1291: Not Collective
1293: Input Parameter:
1294: . snes - SNES context
1296: Output Parameter:
1297: . nfuncs - number of evaluations
1299: Level: intermediate
1301: Notes: Reset every time SNESSolve is called unless SNESSetCountersReset() is used.
1303: .keywords: SNES, nonlinear, get, maximum, unsuccessful, steps
1305: .seealso: SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures(), SNESGetLinearSolveFailures(), SNESSetCountersReset()
1306: @*/
1307: PetscErrorCode SNESGetNumberFunctionEvals(SNES snes, PetscInt *nfuncs)
1308: {
1312: *nfuncs = snes->nfuncs;
1313: return(0);
1314: }
1316: /*@
1317: SNESGetLinearSolveFailures - Gets the number of failed (non-converged)
1318: linear solvers.
1320: Not Collective
1322: Input Parameter:
1323: . snes - SNES context
1325: Output Parameter:
1326: . nfails - number of failed solves
1328: Level: intermediate
1330: Options Database Keys:
1331: . -snes_max_linear_solve_fail <num> - The number of failures before the solve is terminated
1333: Notes:
1334: This counter is reset to zero for each successive call to SNESSolve().
1336: .keywords: SNES, nonlinear, get, number, unsuccessful, steps
1338: .seealso: SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures()
1339: @*/
1340: PetscErrorCode SNESGetLinearSolveFailures(SNES snes,PetscInt *nfails)
1341: {
1345: *nfails = snes->numLinearSolveFailures;
1346: return(0);
1347: }
1349: /*@
1350: SNESSetMaxLinearSolveFailures - the number of failed linear solve attempts
1351: allowed before SNES returns with a diverged reason of SNES_DIVERGED_LINEAR_SOLVE
1353: Logically Collective on SNES
1355: Input Parameters:
1356: + snes - SNES context
1357: - maxFails - maximum allowed linear solve failures
1359: Level: intermediate
1361: Options Database Keys:
1362: . -snes_max_linear_solve_fail <num> - The number of failures before the solve is terminated
1364: Notes: By default this is 0; that is SNES returns on the first failed linear solve
1366: .keywords: SNES, nonlinear, set, maximum, unsuccessful, steps
1368: .seealso: SNESGetLinearSolveFailures(), SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations()
1369: @*/
1370: PetscErrorCode SNESSetMaxLinearSolveFailures(SNES snes, PetscInt maxFails)
1371: {
1375: snes->maxLinearSolveFailures = maxFails;
1376: return(0);
1377: }
1379: /*@
1380: SNESGetMaxLinearSolveFailures - gets the maximum number of linear solve failures that
1381: are allowed before SNES terminates
1383: Not Collective
1385: Input Parameter:
1386: . snes - SNES context
1388: Output Parameter:
1389: . maxFails - maximum of unsuccessful solves allowed
1391: Level: intermediate
1393: Notes: By default this is 1; that is SNES returns on the first failed linear solve
1395: .keywords: SNES, nonlinear, get, maximum, unsuccessful, steps
1397: .seealso: SNESGetLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures(),
1398: @*/
1399: PetscErrorCode SNESGetMaxLinearSolveFailures(SNES snes, PetscInt *maxFails)
1400: {
1404: *maxFails = snes->maxLinearSolveFailures;
1405: return(0);
1406: }
1408: /*@
1409: SNESGetLinearSolveIterations - Gets the total number of linear iterations
1410: used by the nonlinear solver.
1412: Not Collective
1414: Input Parameter:
1415: . snes - SNES context
1417: Output Parameter:
1418: . lits - number of linear iterations
1420: Notes:
1421: This counter is reset to zero for each successive call to SNESSolve() unless SNESSetCountersReset() is used.
1423: 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
1424: then call KSPGetIterationNumber() after the failed solve.
1426: Level: intermediate
1428: .keywords: SNES, nonlinear, get, number, linear, iterations
1430: .seealso: SNESGetIterationNumber(), SNESGetLinearSolveFailures(), SNESGetMaxLinearSolveFailures(), SNESSetCountersReset()
1431: @*/
1432: PetscErrorCode SNESGetLinearSolveIterations(SNES snes,PetscInt *lits)
1433: {
1437: *lits = snes->linear_its;
1438: return(0);
1439: }
1441: /*@
1442: SNESSetCountersReset - Sets whether or not the counters for linear iterations and function evaluations
1443: are reset every time SNESSolve() is called.
1445: Logically Collective on SNES
1447: Input Parameter:
1448: + snes - SNES context
1449: - reset - whether to reset the counters or not
1451: Notes:
1452: This defaults to PETSC_TRUE
1454: Level: developer
1456: .keywords: SNES, nonlinear, set, reset, number, linear, iterations
1458: .seealso: SNESGetNumberFunctionEvals(), SNESGetLinearSolveIterations(), SNESGetNPC()
1459: @*/
1460: PetscErrorCode SNESSetCountersReset(SNES snes,PetscBool reset)
1461: {
1465: snes->counters_reset = reset;
1466: return(0);
1467: }
1470: /*@
1471: SNESSetKSP - Sets a KSP context for the SNES object to use
1473: Not Collective, but the SNES and KSP objects must live on the same MPI_Comm
1475: Input Parameters:
1476: + snes - the SNES context
1477: - ksp - the KSP context
1479: Notes:
1480: The SNES object already has its KSP object, you can obtain with SNESGetKSP()
1481: so this routine is rarely needed.
1483: The KSP object that is already in the SNES object has its reference count
1484: decreased by one.
1486: Level: developer
1488: .keywords: SNES, nonlinear, get, KSP, context
1490: .seealso: KSPGetPC(), SNESCreate(), KSPCreate(), SNESSetKSP()
1491: @*/
1492: PetscErrorCode SNESSetKSP(SNES snes,KSP ksp)
1493: {
1500: PetscObjectReference((PetscObject)ksp);
1501: if (snes->ksp) {PetscObjectDereference((PetscObject)snes->ksp);}
1502: snes->ksp = ksp;
1503: return(0);
1504: }
1506: /* -----------------------------------------------------------*/
1507: /*@
1508: SNESCreate - Creates a nonlinear solver context.
1510: Collective on MPI_Comm
1512: Input Parameters:
1513: . comm - MPI communicator
1515: Output Parameter:
1516: . outsnes - the new SNES context
1518: Options Database Keys:
1519: + -snes_mf - Activates default matrix-free Jacobian-vector products,
1520: and no preconditioning matrix
1521: . -snes_mf_operator - Activates default matrix-free Jacobian-vector
1522: products, and a user-provided preconditioning matrix
1523: as set by SNESSetJacobian()
1524: - -snes_fd - Uses (slow!) finite differences to compute Jacobian
1526: Level: beginner
1528: Developer Notes: SNES always creates a KSP object even though many SNES methods do not use it. This is
1529: unfortunate and should be fixed at some point. The flag snes->usesksp indicates if the
1530: particular method does use KSP and regulates if the information about the KSP is printed
1531: in SNESView(). TSSetFromOptions() does call SNESSetFromOptions() which can lead to users being confused
1532: by help messages about meaningless SNES options.
1534: SNES always creates the snes->kspconvctx even though it is used by only one type. This should
1535: be fixed.
1537: .keywords: SNES, nonlinear, create, context
1539: .seealso: SNESSolve(), SNESDestroy(), SNES, SNESSetLagPreconditioner()
1541: @*/
1542: PetscErrorCode SNESCreate(MPI_Comm comm,SNES *outsnes)
1543: {
1545: SNES snes;
1546: SNESKSPEW *kctx;
1550: *outsnes = NULL;
1551: SNESInitializePackage();
1553: PetscHeaderCreate(snes,SNES_CLASSID,"SNES","Nonlinear solver","SNES",comm,SNESDestroy,SNESView);
1555: snes->ops->converged = SNESConvergedDefault;
1556: snes->usesksp = PETSC_TRUE;
1557: snes->tolerancesset = PETSC_FALSE;
1558: snes->max_its = 50;
1559: snes->max_funcs = 10000;
1560: snes->norm = 0.0;
1561: snes->normschedule = SNES_NORM_ALWAYS;
1562: snes->functype = SNES_FUNCTION_DEFAULT;
1563: #if defined(PETSC_USE_REAL_SINGLE)
1564: snes->rtol = 1.e-5;
1565: #else
1566: snes->rtol = 1.e-8;
1567: #endif
1568: snes->ttol = 0.0;
1569: #if defined(PETSC_USE_REAL_SINGLE)
1570: snes->abstol = 1.e-25;
1571: #else
1572: snes->abstol = 1.e-50;
1573: #endif
1574: #if defined(PETSC_USE_REAL_SINGLE)
1575: snes->stol = 1.e-5;
1576: #else
1577: snes->stol = 1.e-8;
1578: #endif
1579: #if defined(PETSC_USE_REAL_SINGLE)
1580: snes->deltatol = 1.e-6;
1581: #else
1582: snes->deltatol = 1.e-12;
1583: #endif
1584: snes->divtol = 1.e4;
1585: snes->rnorm0 = 0;
1586: snes->nfuncs = 0;
1587: snes->numFailures = 0;
1588: snes->maxFailures = 1;
1589: snes->linear_its = 0;
1590: snes->lagjacobian = 1;
1591: snes->jac_iter = 0;
1592: snes->lagjac_persist = PETSC_FALSE;
1593: snes->lagpreconditioner = 1;
1594: snes->pre_iter = 0;
1595: snes->lagpre_persist = PETSC_FALSE;
1596: snes->numbermonitors = 0;
1597: snes->data = 0;
1598: snes->setupcalled = PETSC_FALSE;
1599: snes->ksp_ewconv = PETSC_FALSE;
1600: snes->nwork = 0;
1601: snes->work = 0;
1602: snes->nvwork = 0;
1603: snes->vwork = 0;
1604: snes->conv_hist_len = 0;
1605: snes->conv_hist_max = 0;
1606: snes->conv_hist = NULL;
1607: snes->conv_hist_its = NULL;
1608: snes->conv_hist_reset = PETSC_TRUE;
1609: snes->counters_reset = PETSC_TRUE;
1610: snes->vec_func_init_set = PETSC_FALSE;
1611: snes->reason = SNES_CONVERGED_ITERATING;
1612: snes->npcside = PC_RIGHT;
1614: snes->mf = PETSC_FALSE;
1615: snes->mf_operator = PETSC_FALSE;
1616: snes->mf_version = 1;
1618: snes->numLinearSolveFailures = 0;
1619: snes->maxLinearSolveFailures = 1;
1621: snes->vizerotolerance = 1.e-8;
1623: /* Set this to true if the implementation of SNESSolve_XXX does compute the residual at the final solution. */
1624: snes->alwayscomputesfinalresidual = PETSC_FALSE;
1626: /* Create context to compute Eisenstat-Walker relative tolerance for KSP */
1627: PetscNewLog(snes,&kctx);
1629: snes->kspconvctx = (void*)kctx;
1630: kctx->version = 2;
1631: kctx->rtol_0 = .3; /* Eisenstat and Walker suggest rtol_0=.5, but
1632: this was too large for some test cases */
1633: kctx->rtol_last = 0.0;
1634: kctx->rtol_max = .9;
1635: kctx->gamma = 1.0;
1636: kctx->alpha = .5*(1.0 + PetscSqrtReal(5.0));
1637: kctx->alpha2 = kctx->alpha;
1638: kctx->threshold = .1;
1639: kctx->lresid_last = 0.0;
1640: kctx->norm_last = 0.0;
1642: *outsnes = snes;
1643: return(0);
1644: }
1646: /*MC
1647: SNESFunction - Functional form used to convey the nonlinear function to be solved by SNES
1649: Synopsis:
1650: #include "petscsnes.h"
1651: PetscErrorCode SNESFunction(SNES snes,Vec x,Vec f,void *ctx);
1653: Input Parameters:
1654: + snes - the SNES context
1655: . x - state at which to evaluate residual
1656: - ctx - optional user-defined function context, passed in with SNESSetFunction()
1658: Output Parameter:
1659: . f - vector to put residual (function value)
1661: Level: intermediate
1663: .seealso: SNESSetFunction(), SNESGetFunction()
1664: M*/
1666: /*@C
1667: SNESSetFunction - Sets the function evaluation routine and function
1668: vector for use by the SNES routines in solving systems of nonlinear
1669: equations.
1671: Logically Collective on SNES
1673: Input Parameters:
1674: + snes - the SNES context
1675: . r - vector to store function value
1676: . f - function evaluation routine; see SNESFunction for calling sequence details
1677: - ctx - [optional] user-defined context for private data for the
1678: function evaluation routine (may be NULL)
1680: Notes:
1681: The Newton-like methods typically solve linear systems of the form
1682: $ f'(x) x = -f(x),
1683: where f'(x) denotes the Jacobian matrix and f(x) is the function.
1685: Level: beginner
1687: .keywords: SNES, nonlinear, set, function
1689: .seealso: SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESSetPicard(), SNESFunction
1690: @*/
1691: PetscErrorCode SNESSetFunction(SNES snes,Vec r,PetscErrorCode (*f)(SNES,Vec,Vec,void*),void *ctx)
1692: {
1694: DM dm;
1698: if (r) {
1701: PetscObjectReference((PetscObject)r);
1702: VecDestroy(&snes->vec_func);
1704: snes->vec_func = r;
1705: }
1706: SNESGetDM(snes,&dm);
1707: DMSNESSetFunction(dm,f,ctx);
1708: return(0);
1709: }
1712: /*@C
1713: SNESSetInitialFunction - Sets the function vector to be used as the
1714: function norm at the initialization of the method. In some
1715: instances, the user has precomputed the function before calling
1716: SNESSolve. This function allows one to avoid a redundant call
1717: to SNESComputeFunction in that case.
1719: Logically Collective on SNES
1721: Input Parameters:
1722: + snes - the SNES context
1723: - f - vector to store function value
1725: Notes:
1726: This should not be modified during the solution procedure.
1728: This is used extensively in the SNESFAS hierarchy and in nonlinear preconditioning.
1730: Level: developer
1732: .keywords: SNES, nonlinear, set, function
1734: .seealso: SNESSetFunction(), SNESComputeFunction(), SNESSetInitialFunctionNorm()
1735: @*/
1736: PetscErrorCode SNESSetInitialFunction(SNES snes, Vec f)
1737: {
1739: Vec vec_func;
1745: if (snes->npcside== PC_LEFT && snes->functype == SNES_FUNCTION_PRECONDITIONED) {
1746: snes->vec_func_init_set = PETSC_FALSE;
1747: return(0);
1748: }
1749: SNESGetFunction(snes,&vec_func,NULL,NULL);
1750: VecCopy(f, vec_func);
1752: snes->vec_func_init_set = PETSC_TRUE;
1753: return(0);
1754: }
1756: /*@
1757: SNESSetNormSchedule - Sets the SNESNormSchedule used in covergence and monitoring
1758: of the SNES method.
1760: Logically Collective on SNES
1762: Input Parameters:
1763: + snes - the SNES context
1764: - normschedule - the frequency of norm computation
1766: Options Database Key:
1767: . -snes_norm_schedule <none, always, initialonly, finalonly, initalfinalonly>
1769: Notes:
1770: Only certain SNES methods support certain SNESNormSchedules. Most require evaluation
1771: of the nonlinear function and the taking of its norm at every iteration to
1772: even ensure convergence at all. However, methods such as custom Gauss-Seidel methods
1773: (SNESNGS) and the like do not require the norm of the function to be computed, and therfore
1774: may either be monitored for convergence or not. As these are often used as nonlinear
1775: preconditioners, monitoring the norm of their error is not a useful enterprise within
1776: their solution.
1778: Level: developer
1780: .keywords: SNES, nonlinear, set, function, norm, type
1782: .seealso: SNESGetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
1783: @*/
1784: PetscErrorCode SNESSetNormSchedule(SNES snes, SNESNormSchedule normschedule)
1785: {
1788: snes->normschedule = normschedule;
1789: return(0);
1790: }
1793: /*@
1794: SNESGetNormSchedule - Gets the SNESNormSchedule used in covergence and monitoring
1795: of the SNES method.
1797: Logically Collective on SNES
1799: Input Parameters:
1800: + snes - the SNES context
1801: - normschedule - the type of the norm used
1803: Level: advanced
1805: .keywords: SNES, nonlinear, set, function, norm, type
1807: .seealso: SNESSetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
1808: @*/
1809: PetscErrorCode SNESGetNormSchedule(SNES snes, SNESNormSchedule *normschedule)
1810: {
1813: *normschedule = snes->normschedule;
1814: return(0);
1815: }
1818: /*@
1819: SNESSetFunctionNorm - Sets the last computed residual norm.
1821: Logically Collective on SNES
1823: Input Parameters:
1824: + snes - the SNES context
1826: - normschedule - the frequency of norm computation
1828: Level: developer
1830: .keywords: SNES, nonlinear, set, function, norm, type
1831: .seealso: SNESGetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
1832: @*/
1833: PetscErrorCode SNESSetFunctionNorm(SNES snes, PetscReal norm)
1834: {
1837: snes->norm = norm;
1838: return(0);
1839: }
1841: /*@
1842: SNESGetFunctionNorm - Gets the last computed norm of the residual
1844: Not Collective
1846: Input Parameter:
1847: . snes - the SNES context
1849: Output Parameter:
1850: . norm - the last computed residual norm
1852: Level: developer
1854: .keywords: SNES, nonlinear, set, function, norm, type
1855: .seealso: SNESSetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
1856: @*/
1857: PetscErrorCode SNESGetFunctionNorm(SNES snes, PetscReal *norm)
1858: {
1862: *norm = snes->norm;
1863: return(0);
1864: }
1866: /*@C
1867: SNESSetFunctionType - Sets the SNESNormSchedule used in covergence and monitoring
1868: of the SNES method.
1870: Logically Collective on SNES
1872: Input Parameters:
1873: + snes - the SNES context
1874: - normschedule - the frequency of norm computation
1876: Notes:
1877: Only certain SNES methods support certain SNESNormSchedules. Most require evaluation
1878: of the nonlinear function and the taking of its norm at every iteration to
1879: even ensure convergence at all. However, methods such as custom Gauss-Seidel methods
1880: (SNESNGS) and the like do not require the norm of the function to be computed, and therfore
1881: may either be monitored for convergence or not. As these are often used as nonlinear
1882: preconditioners, monitoring the norm of their error is not a useful enterprise within
1883: their solution.
1885: Level: developer
1887: .keywords: SNES, nonlinear, set, function, norm, type
1889: .seealso: SNESGetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
1890: @*/
1891: PetscErrorCode SNESSetFunctionType(SNES snes, SNESFunctionType type)
1892: {
1895: snes->functype = type;
1896: return(0);
1897: }
1900: /*@C
1901: SNESGetFunctionType - Gets the SNESNormSchedule used in covergence and monitoring
1902: of the SNES method.
1904: Logically Collective on SNES
1906: Input Parameters:
1907: + snes - the SNES context
1908: - normschedule - the type of the norm used
1910: Level: advanced
1912: .keywords: SNES, nonlinear, set, function, norm, type
1914: .seealso: SNESSetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
1915: @*/
1916: PetscErrorCode SNESGetFunctionType(SNES snes, SNESFunctionType *type)
1917: {
1920: *type = snes->functype;
1921: return(0);
1922: }
1924: /*MC
1925: SNESNGSFunction - function used to convey a Gauss-Seidel sweep on the nonlinear function
1927: Synopsis:
1928: #include <petscsnes.h>
1929: $ SNESNGSFunction(SNES snes,Vec x,Vec b,void *ctx);
1931: + X - solution vector
1932: . B - RHS vector
1933: - ctx - optional user-defined Gauss-Seidel context
1935: Level: intermediate
1937: .seealso: SNESSetNGS(), SNESGetNGS()
1938: M*/
1940: /*@C
1941: SNESSetNGS - Sets the user nonlinear Gauss-Seidel routine for
1942: use with composed nonlinear solvers.
1944: Input Parameters:
1945: + snes - the SNES context
1946: . f - function evaluation routine to apply Gauss-Seidel see SNESNGSFunction
1947: - ctx - [optional] user-defined context for private data for the
1948: smoother evaluation routine (may be NULL)
1950: Notes:
1951: The NGS routines are used by the composed nonlinear solver to generate
1952: a problem appropriate update to the solution, particularly FAS.
1954: Level: intermediate
1956: .keywords: SNES, nonlinear, set, Gauss-Seidel
1958: .seealso: SNESGetFunction(), SNESComputeNGS()
1959: @*/
1960: PetscErrorCode SNESSetNGS(SNES snes,PetscErrorCode (*f)(SNES,Vec,Vec,void*),void *ctx)
1961: {
1963: DM dm;
1967: SNESGetDM(snes,&dm);
1968: DMSNESSetNGS(dm,f,ctx);
1969: return(0);
1970: }
1972: PETSC_EXTERN PetscErrorCode SNESPicardComputeFunction(SNES snes,Vec x,Vec f,void *ctx)
1973: {
1975: DM dm;
1976: DMSNES sdm;
1979: SNESGetDM(snes,&dm);
1980: DMGetDMSNES(dm,&sdm);
1981: /* A(x)*x - b(x) */
1982: if (sdm->ops->computepfunction) {
1983: (*sdm->ops->computepfunction)(snes,x,f,sdm->pctx);
1984: } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Must call SNESSetPicard() to provide Picard function.");
1986: if (sdm->ops->computepjacobian) {
1987: (*sdm->ops->computepjacobian)(snes,x,snes->jacobian,snes->jacobian_pre,sdm->pctx);
1988: } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Must call SNESSetPicard() to provide Picard matrix.");
1989: VecScale(f,-1.0);
1990: MatMultAdd(snes->jacobian,x,f,f);
1991: return(0);
1992: }
1994: PETSC_EXTERN PetscErrorCode SNESPicardComputeJacobian(SNES snes,Vec x1,Mat J,Mat B,void *ctx)
1995: {
1997: /* the jacobian matrix should be pre-filled in SNESPicardComputeFunction */
1998: return(0);
1999: }
2001: /*@C
2002: SNESSetPicard - Use SNES to solve the semilinear-system A(x) x = b(x) via a Picard type iteration (Picard linearization)
2004: Logically Collective on SNES
2006: Input Parameters:
2007: + snes - the SNES context
2008: . r - vector to store function value
2009: . b - function evaluation routine
2010: . Amat - matrix with which A(x) x - b(x) is to be computed
2011: . Pmat - matrix from which preconditioner is computed (usually the same as Amat)
2012: . J - function to compute matrix value, see SNESJacobianFunction for details on its calling sequence
2013: - ctx - [optional] user-defined context for private data for the
2014: function evaluation routine (may be NULL)
2016: Notes:
2017: 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
2018: 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.
2020: One can call SNESSetPicard() or SNESSetFunction() (and possibly SNESSetJacobian()) but cannot call both
2022: $ 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}
2023: $ Note that when an exact solver is used this corresponds to the "classic" Picard A(x^{n}) x^{n+1} = b(x^{n}) iteration.
2025: Run with -snes_mf_operator to solve the system with Newton's method using A(x^{n}) to construct the preconditioner.
2027: We implement the defect correction form of the Picard iteration because it converges much more generally when inexact linear solvers are used then
2028: the direct Picard iteration A(x^n) x^{n+1} = b(x^n)
2030: 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
2031: 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
2032: different please contact us at petsc-dev@mcs.anl.gov and we'll have an entirely new argument :-).
2034: Level: intermediate
2036: .keywords: SNES, nonlinear, set, function
2038: .seealso: SNESGetFunction(), SNESSetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESGetPicard(), SNESLineSearchPreCheckPicard(), SNESJacobianFunction
2039: @*/
2040: 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)
2041: {
2043: DM dm;
2047: SNESGetDM(snes, &dm);
2048: DMSNESSetPicard(dm,b,J,ctx);
2049: SNESSetFunction(snes,r,SNESPicardComputeFunction,ctx);
2050: SNESSetJacobian(snes,Amat,Pmat,SNESPicardComputeJacobian,ctx);
2051: return(0);
2052: }
2054: /*@C
2055: SNESGetPicard - Returns the context for the Picard iteration
2057: Not Collective, but Vec is parallel if SNES is parallel. Collective if Vec is requested, but has not been created yet.
2059: Input Parameter:
2060: . snes - the SNES context
2062: Output Parameter:
2063: + r - the function (or NULL)
2064: . f - the function (or NULL); see SNESFunction for calling sequence details
2065: . Amat - the matrix used to defined the operation A(x) x - b(x) (or NULL)
2066: . Pmat - the matrix from which the preconditioner will be constructed (or NULL)
2067: . J - the function for matrix evaluation (or NULL); see SNESJacobianFunction for calling sequence details
2068: - ctx - the function context (or NULL)
2070: Level: advanced
2072: .keywords: SNES, nonlinear, get, function
2074: .seealso: SNESSetPicard(), SNESGetFunction(), SNESGetJacobian(), SNESGetDM(), SNESFunction, SNESJacobianFunction
2075: @*/
2076: 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)
2077: {
2079: DM dm;
2083: SNESGetFunction(snes,r,NULL,NULL);
2084: SNESGetJacobian(snes,Amat,Pmat,NULL,NULL);
2085: SNESGetDM(snes,&dm);
2086: DMSNESGetPicard(dm,f,J,ctx);
2087: return(0);
2088: }
2090: /*@C
2091: SNESSetComputeInitialGuess - Sets a routine used to compute an initial guess for the problem
2093: Logically Collective on SNES
2095: Input Parameters:
2096: + snes - the SNES context
2097: . func - function evaluation routine
2098: - ctx - [optional] user-defined context for private data for the
2099: function evaluation routine (may be NULL)
2101: Calling sequence of func:
2102: $ func (SNES snes,Vec x,void *ctx);
2104: . f - function vector
2105: - ctx - optional user-defined function context
2107: Level: intermediate
2109: .keywords: SNES, nonlinear, set, function
2111: .seealso: SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian()
2112: @*/
2113: PetscErrorCode SNESSetComputeInitialGuess(SNES snes,PetscErrorCode (*func)(SNES,Vec,void*),void *ctx)
2114: {
2117: if (func) snes->ops->computeinitialguess = func;
2118: if (ctx) snes->initialguessP = ctx;
2119: return(0);
2120: }
2122: /* --------------------------------------------------------------- */
2123: /*@C
2124: SNESGetRhs - Gets the vector for solving F(x) = rhs. If rhs is not set
2125: it assumes a zero right hand side.
2127: Logically Collective on SNES
2129: Input Parameter:
2130: . snes - the SNES context
2132: Output Parameter:
2133: . rhs - the right hand side vector or NULL if the right hand side vector is null
2135: Level: intermediate
2137: .keywords: SNES, nonlinear, get, function, right hand side
2139: .seealso: SNESGetSolution(), SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESSetFunction()
2140: @*/
2141: PetscErrorCode SNESGetRhs(SNES snes,Vec *rhs)
2142: {
2146: *rhs = snes->vec_rhs;
2147: return(0);
2148: }
2150: /*@
2151: SNESComputeFunction - Calls the function that has been set with SNESSetFunction().
2153: Collective on SNES
2155: Input Parameters:
2156: + snes - the SNES context
2157: - x - input vector
2159: Output Parameter:
2160: . y - function vector, as set by SNESSetFunction()
2162: Notes:
2163: SNESComputeFunction() is typically used within nonlinear solvers
2164: implementations, so most users would not generally call this routine
2165: themselves.
2167: Level: developer
2169: .keywords: SNES, nonlinear, compute, function
2171: .seealso: SNESSetFunction(), SNESGetFunction()
2172: @*/
2173: PetscErrorCode SNESComputeFunction(SNES snes,Vec x,Vec y)
2174: {
2176: DM dm;
2177: DMSNES sdm;
2185: VecValidValues(x,2,PETSC_TRUE);
2187: SNESGetDM(snes,&dm);
2188: DMGetDMSNES(dm,&sdm);
2189: if (sdm->ops->computefunction) {
2190: if (sdm->ops->computefunction != SNESObjectiveComputeFunctionDefaultFD) {
2191: PetscLogEventBegin(SNES_FunctionEval,snes,x,y,0);
2192: }
2193: VecLockPush(x);
2194: PetscStackPush("SNES user function");
2195: (*sdm->ops->computefunction)(snes,x,y,sdm->functionctx);
2196: PetscStackPop;
2197: VecLockPop(x);
2198: if (sdm->ops->computefunction != SNESObjectiveComputeFunctionDefaultFD) {
2199: PetscLogEventEnd(SNES_FunctionEval,snes,x,y,0);
2200: }
2201: } else if (snes->vec_rhs) {
2202: MatMult(snes->jacobian, x, y);
2203: } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Must call SNESSetFunction() or SNESSetDM() before SNESComputeFunction(), likely called from SNESSolve().");
2204: if (snes->vec_rhs) {
2205: VecAXPY(y,-1.0,snes->vec_rhs);
2206: }
2207: snes->nfuncs++;
2208: /*
2209: domainerror might not be set on all processes; so we tag vector locally with Inf and the next inner product or norm will
2210: propagate the value to all processes
2211: */
2212: if (snes->domainerror) {
2213: VecSetInf(y);
2214: }
2215: return(0);
2216: }
2218: /*@
2219: SNESComputeNGS - Calls the Gauss-Seidel function that has been set with SNESSetNGS().
2221: Collective on SNES
2223: Input Parameters:
2224: + snes - the SNES context
2225: . x - input vector
2226: - b - rhs vector
2228: Output Parameter:
2229: . x - new solution vector
2231: Notes:
2232: SNESComputeNGS() is typically used within composed nonlinear solver
2233: implementations, so most users would not generally call this routine
2234: themselves.
2236: Level: developer
2238: .keywords: SNES, nonlinear, compute, function
2240: .seealso: SNESSetNGS(), SNESComputeFunction()
2241: @*/
2242: PetscErrorCode SNESComputeNGS(SNES snes,Vec b,Vec x)
2243: {
2245: DM dm;
2246: DMSNES sdm;
2254: if (b) {VecValidValues(b,2,PETSC_TRUE);}
2255: PetscLogEventBegin(SNES_NGSEval,snes,x,b,0);
2256: SNESGetDM(snes,&dm);
2257: DMGetDMSNES(dm,&sdm);
2258: if (sdm->ops->computegs) {
2259: if (b) {VecLockPush(b);}
2260: PetscStackPush("SNES user NGS");
2261: (*sdm->ops->computegs)(snes,x,b,sdm->gsctx);
2262: PetscStackPop;
2263: if (b) {VecLockPop(b);}
2264: } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Must call SNESSetNGS() before SNESComputeNGS(), likely called from SNESSolve().");
2265: PetscLogEventEnd(SNES_NGSEval,snes,x,b,0);
2266: return(0);
2267: }
2269: /*@
2270: SNESComputeJacobian - Computes the Jacobian matrix that has been set with SNESSetJacobian().
2272: Collective on SNES and Mat
2274: Input Parameters:
2275: + snes - the SNES context
2276: - x - input vector
2278: Output Parameters:
2279: + A - Jacobian matrix
2280: - B - optional preconditioning matrix
2282: Options Database Keys:
2283: + -snes_lag_preconditioner <lag>
2284: . -snes_lag_jacobian <lag>
2285: . -snes_compare_explicit - Compare the computed Jacobian to the finite difference Jacobian and output the differences
2286: . -snes_compare_explicit_draw - Compare the computed Jacobian to the finite difference Jacobian and draw the result
2287: . -snes_compare_explicit_contour - Compare the computed Jacobian to the finite difference Jacobian and draw a contour plot with the result
2288: . -snes_compare_operator - Make the comparison options above use the operator instead of the preconditioning matrix
2289: . -snes_compare_coloring - Compute the finite difference Jacobian using coloring and display norms of difference
2290: . -snes_compare_coloring_display - Compute the finite differece Jacobian using coloring and display verbose differences
2291: . -snes_compare_coloring_threshold - Display only those matrix entries that differ by more than a given threshold
2292: . -snes_compare_coloring_threshold_atol - Absolute tolerance for difference in matrix entries to be displayed by -snes_compare_coloring_threshold
2293: . -snes_compare_coloring_threshold_rtol - Relative tolerance for difference in matrix entries to be displayed by -snes_compare_coloring_threshold
2294: . -snes_compare_coloring_draw - Compute the finite differece Jacobian using coloring and draw differences
2295: - -snes_compare_coloring_draw_contour - Compute the finite differece Jacobian using coloring and show contours of matrices and differences
2298: Notes:
2299: Most users should not need to explicitly call this routine, as it
2300: is used internally within the nonlinear solvers.
2302: Level: developer
2304: .keywords: SNES, compute, Jacobian, matrix
2306: .seealso: SNESSetJacobian(), KSPSetOperators(), MatStructure, SNESSetLagPreconditioner(), SNESSetLagJacobian()
2307: @*/
2308: PetscErrorCode SNESComputeJacobian(SNES snes,Vec X,Mat A,Mat B)
2309: {
2311: PetscBool flag;
2312: DM dm;
2313: DMSNES sdm;
2314: KSP ksp;
2320: VecValidValues(X,2,PETSC_TRUE);
2321: SNESGetDM(snes,&dm);
2322: DMGetDMSNES(dm,&sdm);
2324: if (!sdm->ops->computejacobian) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_USER,"Must call SNESSetJacobian(), DMSNESSetJacobian(), DMDASNESSetJacobianLocal(), etc");
2326: /* make sure that MatAssemblyBegin/End() is called on A matrix if it is matrix free */
2328: if (snes->lagjacobian == -2) {
2329: snes->lagjacobian = -1;
2331: PetscInfo(snes,"Recomputing Jacobian/preconditioner because lag is -2 (means compute Jacobian, but then never again) \n");
2332: } else if (snes->lagjacobian == -1) {
2333: PetscInfo(snes,"Reusing Jacobian/preconditioner because lag is -1\n");
2334: PetscObjectTypeCompare((PetscObject)A,MATMFFD,&flag);
2335: if (flag) {
2336: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
2337: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
2338: }
2339: return(0);
2340: } else if (snes->lagjacobian > 1 && (snes->iter + snes->jac_iter) % snes->lagjacobian) {
2341: PetscInfo2(snes,"Reusing Jacobian/preconditioner because lag is %D and SNES iteration is %D\n",snes->lagjacobian,snes->iter);
2342: PetscObjectTypeCompare((PetscObject)A,MATMFFD,&flag);
2343: if (flag) {
2344: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
2345: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
2346: }
2347: return(0);
2348: }
2349: if (snes->npc && snes->npcside== PC_LEFT) {
2350: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
2351: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
2352: return(0);
2353: }
2355: PetscLogEventBegin(SNES_JacobianEval,snes,X,A,B);
2356: VecLockPush(X);
2357: PetscStackPush("SNES user Jacobian function");
2358: (*sdm->ops->computejacobian)(snes,X,A,B,sdm->jacobianctx);
2359: PetscStackPop;
2360: VecLockPop(X);
2361: PetscLogEventEnd(SNES_JacobianEval,snes,X,A,B);
2363: /* the next line ensures that snes->ksp exists */
2364: SNESGetKSP(snes,&ksp);
2365: if (snes->lagpreconditioner == -2) {
2366: PetscInfo(snes,"Rebuilding preconditioner exactly once since lag is -2\n");
2367: KSPSetReusePreconditioner(snes->ksp,PETSC_FALSE);
2368: snes->lagpreconditioner = -1;
2369: } else if (snes->lagpreconditioner == -1) {
2370: PetscInfo(snes,"Reusing preconditioner because lag is -1\n");
2371: KSPSetReusePreconditioner(snes->ksp,PETSC_TRUE);
2372: } else if (snes->lagpreconditioner > 1 && (snes->iter + snes->pre_iter) % snes->lagpreconditioner) {
2373: PetscInfo2(snes,"Reusing preconditioner because lag is %D and SNES iteration is %D\n",snes->lagpreconditioner,snes->iter);
2374: KSPSetReusePreconditioner(snes->ksp,PETSC_TRUE);
2375: } else {
2376: PetscInfo(snes,"Rebuilding preconditioner\n");
2377: KSPSetReusePreconditioner(snes->ksp,PETSC_FALSE);
2378: }
2380: /* make sure user returned a correct Jacobian and preconditioner */
2383: {
2384: PetscBool flag = PETSC_FALSE,flag_draw = PETSC_FALSE,flag_contour = PETSC_FALSE,flag_operator = PETSC_FALSE;
2385: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_explicit",NULL,NULL,&flag);
2386: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_explicit_draw",NULL,NULL,&flag_draw);
2387: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_explicit_draw_contour",NULL,NULL,&flag_contour);
2388: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_operator",NULL,NULL,&flag_operator);
2389: if (flag || flag_draw || flag_contour) {
2390: Mat Bexp_mine = NULL,Bexp,FDexp;
2391: PetscViewer vdraw,vstdout;
2392: PetscBool flg;
2393: if (flag_operator) {
2394: MatComputeExplicitOperator(A,&Bexp_mine);
2395: Bexp = Bexp_mine;
2396: } else {
2397: /* See if the preconditioning matrix can be viewed and added directly */
2398: PetscObjectTypeCompareAny((PetscObject)B,&flg,MATSEQAIJ,MATMPIAIJ,MATSEQDENSE,MATMPIDENSE,MATSEQBAIJ,MATMPIBAIJ,MATSEQSBAIJ,MATMPIBAIJ,"");
2399: if (flg) Bexp = B;
2400: else {
2401: /* If the "preconditioning" matrix is itself MATSHELL or some other type without direct support */
2402: MatComputeExplicitOperator(B,&Bexp_mine);
2403: Bexp = Bexp_mine;
2404: }
2405: }
2406: MatConvert(Bexp,MATSAME,MAT_INITIAL_MATRIX,&FDexp);
2407: SNESComputeJacobianDefault(snes,X,FDexp,FDexp,NULL);
2408: PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)snes),&vstdout);
2409: if (flag_draw || flag_contour) {
2410: PetscViewerDrawOpen(PetscObjectComm((PetscObject)snes),0,"Explicit Jacobians",PETSC_DECIDE,PETSC_DECIDE,300,300,&vdraw);
2411: if (flag_contour) {PetscViewerPushFormat(vdraw,PETSC_VIEWER_DRAW_CONTOUR);}
2412: } else vdraw = NULL;
2413: PetscViewerASCIIPrintf(vstdout,"Explicit %s\n",flag_operator ? "Jacobian" : "preconditioning Jacobian");
2414: if (flag) {MatView(Bexp,vstdout);}
2415: if (vdraw) {MatView(Bexp,vdraw);}
2416: PetscViewerASCIIPrintf(vstdout,"Finite difference Jacobian\n");
2417: if (flag) {MatView(FDexp,vstdout);}
2418: if (vdraw) {MatView(FDexp,vdraw);}
2419: MatAYPX(FDexp,-1.0,Bexp,SAME_NONZERO_PATTERN);
2420: PetscViewerASCIIPrintf(vstdout,"User-provided matrix minus finite difference Jacobian\n");
2421: if (flag) {MatView(FDexp,vstdout);}
2422: if (vdraw) { /* Always use contour for the difference */
2423: PetscViewerPushFormat(vdraw,PETSC_VIEWER_DRAW_CONTOUR);
2424: MatView(FDexp,vdraw);
2425: PetscViewerPopFormat(vdraw);
2426: }
2427: if (flag_contour) {PetscViewerPopFormat(vdraw);}
2428: PetscViewerDestroy(&vdraw);
2429: MatDestroy(&Bexp_mine);
2430: MatDestroy(&FDexp);
2431: }
2432: }
2433: {
2434: PetscBool flag = PETSC_FALSE,flag_display = PETSC_FALSE,flag_draw = PETSC_FALSE,flag_contour = PETSC_FALSE,flag_threshold = PETSC_FALSE;
2435: PetscReal threshold_atol = PETSC_SQRT_MACHINE_EPSILON,threshold_rtol = 10*PETSC_SQRT_MACHINE_EPSILON;
2436: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_coloring",NULL,NULL,&flag);
2437: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_coloring_display",NULL,NULL,&flag_display);
2438: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_coloring_draw",NULL,NULL,&flag_draw);
2439: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_coloring_draw_contour",NULL,NULL,&flag_contour);
2440: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_compare_coloring_threshold",NULL,NULL,&flag_threshold);
2441: if (flag_threshold) {
2442: PetscOptionsGetReal(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-snes_compare_coloring_threshold_rtol",&threshold_rtol,NULL);
2443: PetscOptionsGetReal(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-snes_compare_coloring_threshold_atol",&threshold_atol,NULL);
2444: }
2445: if (flag || flag_display || flag_draw || flag_contour || flag_threshold) {
2446: Mat Bfd;
2447: PetscViewer vdraw,vstdout;
2448: MatColoring coloring;
2449: ISColoring iscoloring;
2450: MatFDColoring matfdcoloring;
2451: PetscErrorCode (*func)(SNES,Vec,Vec,void*);
2452: void *funcctx;
2453: PetscReal norm1,norm2,normmax;
2455: MatDuplicate(B,MAT_DO_NOT_COPY_VALUES,&Bfd);
2456: MatColoringCreate(Bfd,&coloring);
2457: MatColoringSetType(coloring,MATCOLORINGSL);
2458: MatColoringSetFromOptions(coloring);
2459: MatColoringApply(coloring,&iscoloring);
2460: MatColoringDestroy(&coloring);
2461: MatFDColoringCreate(Bfd,iscoloring,&matfdcoloring);
2462: MatFDColoringSetFromOptions(matfdcoloring);
2463: MatFDColoringSetUp(Bfd,iscoloring,matfdcoloring);
2464: ISColoringDestroy(&iscoloring);
2466: /* This method of getting the function is currently unreliable since it doesn't work for DM local functions. */
2467: SNESGetFunction(snes,NULL,&func,&funcctx);
2468: MatFDColoringSetFunction(matfdcoloring,(PetscErrorCode (*)(void))func,funcctx);
2469: PetscObjectSetOptionsPrefix((PetscObject)matfdcoloring,((PetscObject)snes)->prefix);
2470: PetscObjectAppendOptionsPrefix((PetscObject)matfdcoloring,"coloring_");
2471: MatFDColoringSetFromOptions(matfdcoloring);
2472: MatFDColoringApply(Bfd,matfdcoloring,X,snes);
2473: MatFDColoringDestroy(&matfdcoloring);
2475: PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)snes),&vstdout);
2476: if (flag_draw || flag_contour) {
2477: PetscViewerDrawOpen(PetscObjectComm((PetscObject)snes),0,"Colored Jacobians",PETSC_DECIDE,PETSC_DECIDE,300,300,&vdraw);
2478: if (flag_contour) {PetscViewerPushFormat(vdraw,PETSC_VIEWER_DRAW_CONTOUR);}
2479: } else vdraw = NULL;
2480: PetscViewerASCIIPrintf(vstdout,"Explicit preconditioning Jacobian\n");
2481: if (flag_display) {MatView(B,vstdout);}
2482: if (vdraw) {MatView(B,vdraw);}
2483: PetscViewerASCIIPrintf(vstdout,"Colored Finite difference Jacobian\n");
2484: if (flag_display) {MatView(Bfd,vstdout);}
2485: if (vdraw) {MatView(Bfd,vdraw);}
2486: MatAYPX(Bfd,-1.0,B,SAME_NONZERO_PATTERN);
2487: MatNorm(Bfd,NORM_1,&norm1);
2488: MatNorm(Bfd,NORM_FROBENIUS,&norm2);
2489: MatNorm(Bfd,NORM_MAX,&normmax);
2490: PetscViewerASCIIPrintf(vstdout,"User-provided matrix minus finite difference Jacobian, norm1=%g normFrob=%g normmax=%g\n",(double)norm1,(double)norm2,(double)normmax);
2491: if (flag_display) {MatView(Bfd,vstdout);}
2492: if (vdraw) { /* Always use contour for the difference */
2493: PetscViewerPushFormat(vdraw,PETSC_VIEWER_DRAW_CONTOUR);
2494: MatView(Bfd,vdraw);
2495: PetscViewerPopFormat(vdraw);
2496: }
2497: if (flag_contour) {PetscViewerPopFormat(vdraw);}
2499: if (flag_threshold) {
2500: PetscInt bs,rstart,rend,i;
2501: MatGetBlockSize(B,&bs);
2502: MatGetOwnershipRange(B,&rstart,&rend);
2503: for (i=rstart; i<rend; i++) {
2504: const PetscScalar *ba,*ca;
2505: const PetscInt *bj,*cj;
2506: PetscInt bn,cn,j,maxentrycol = -1,maxdiffcol = -1,maxrdiffcol = -1;
2507: PetscReal maxentry = 0,maxdiff = 0,maxrdiff = 0;
2508: MatGetRow(B,i,&bn,&bj,&ba);
2509: MatGetRow(Bfd,i,&cn,&cj,&ca);
2510: if (bn != cn) SETERRQ(((PetscObject)A)->comm,PETSC_ERR_PLIB,"Unexpected different nonzero pattern in -snes_compare_coloring_threshold");
2511: for (j=0; j<bn; j++) {
2512: PetscReal rdiff = PetscAbsScalar(ca[j]) / (threshold_atol + threshold_rtol*PetscAbsScalar(ba[j]));
2513: if (PetscAbsScalar(ba[j]) > PetscAbs(maxentry)) {
2514: maxentrycol = bj[j];
2515: maxentry = PetscRealPart(ba[j]);
2516: }
2517: if (PetscAbsScalar(ca[j]) > PetscAbs(maxdiff)) {
2518: maxdiffcol = bj[j];
2519: maxdiff = PetscRealPart(ca[j]);
2520: }
2521: if (rdiff > maxrdiff) {
2522: maxrdiffcol = bj[j];
2523: maxrdiff = rdiff;
2524: }
2525: }
2526: if (maxrdiff > 1) {
2527: 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);
2528: for (j=0; j<bn; j++) {
2529: PetscReal rdiff;
2530: rdiff = PetscAbsScalar(ca[j]) / (threshold_atol + threshold_rtol*PetscAbsScalar(ba[j]));
2531: if (rdiff > 1) {
2532: PetscViewerASCIIPrintf(vstdout," (%D,%g:%g)",bj[j],(double)PetscRealPart(ba[j]),(double)PetscRealPart(ca[j]));
2533: }
2534: }
2535: PetscViewerASCIIPrintf(vstdout,"\n",i,maxentry,maxdiff,maxrdiff);
2536: }
2537: MatRestoreRow(B,i,&bn,&bj,&ba);
2538: MatRestoreRow(Bfd,i,&cn,&cj,&ca);
2539: }
2540: }
2541: PetscViewerDestroy(&vdraw);
2542: MatDestroy(&Bfd);
2543: }
2544: }
2545: return(0);
2546: }
2548: /*MC
2549: SNESJacobianFunction - Function used to convey the nonlinear Jacobian of the function to be solved by SNES
2551: Synopsis:
2552: #include "petscsnes.h"
2553: PetscErrorCode SNESJacobianFunction(SNES snes,Vec x,Mat Amat,Mat Pmat,void *ctx);
2555: + x - input vector
2556: . Amat - the matrix that defines the (approximate) Jacobian
2557: . Pmat - the matrix to be used in constructing the preconditioner, usually the same as Amat.
2558: - ctx - [optional] user-defined Jacobian context
2560: Level: intermediate
2562: .seealso: SNESSetFunction(), SNESGetFunction(), SNESSetJacobian(), SNESGetJacobian()
2563: M*/
2565: /*@C
2566: SNESSetJacobian - Sets the function to compute Jacobian as well as the
2567: location to store the matrix.
2569: Logically Collective on SNES and Mat
2571: Input Parameters:
2572: + snes - the SNES context
2573: . Amat - the matrix that defines the (approximate) Jacobian
2574: . Pmat - the matrix to be used in constructing the preconditioner, usually the same as Amat.
2575: . J - Jacobian evaluation routine (if NULL then SNES retains any previously set value), see SNESJacobianFunction for details
2576: - ctx - [optional] user-defined context for private data for the
2577: Jacobian evaluation routine (may be NULL) (if NULL then SNES retains any previously set value)
2579: Notes:
2580: If the Amat matrix and Pmat matrix are different you must call MatAssemblyBegin/End() on
2581: each matrix.
2583: If you know the operator Amat has a null space you can use MatSetNullSpace() and MatSetTransposeNullSpace() to supply the null
2584: space to Amat and the KSP solvers will automatically use that null space as needed during the solution process.
2586: If using SNESComputeJacobianDefaultColor() to assemble a Jacobian, the ctx argument
2587: must be a MatFDColoring.
2589: Other defect-correction schemes can be used by computing a different matrix in place of the Jacobian. One common
2590: example is to use the "Picard linearization" which only differentiates through the highest order parts of each term.
2592: Level: beginner
2594: .keywords: SNES, nonlinear, set, Jacobian, matrix
2596: .seealso: KSPSetOperators(), SNESSetFunction(), MatMFFDComputeJacobian(), SNESComputeJacobianDefaultColor(), MatStructure, J,
2597: SNESSetPicard(), SNESJacobianFunction
2598: @*/
2599: PetscErrorCode SNESSetJacobian(SNES snes,Mat Amat,Mat Pmat,PetscErrorCode (*J)(SNES,Vec,Mat,Mat,void*),void *ctx)
2600: {
2602: DM dm;
2610: SNESGetDM(snes,&dm);
2611: DMSNESSetJacobian(dm,J,ctx);
2612: if (Amat) {
2613: PetscObjectReference((PetscObject)Amat);
2614: MatDestroy(&snes->jacobian);
2616: snes->jacobian = Amat;
2617: }
2618: if (Pmat) {
2619: PetscObjectReference((PetscObject)Pmat);
2620: MatDestroy(&snes->jacobian_pre);
2622: snes->jacobian_pre = Pmat;
2623: }
2624: return(0);
2625: }
2627: /*@C
2628: SNESGetJacobian - Returns the Jacobian matrix and optionally the user
2629: provided context for evaluating the Jacobian.
2631: Not Collective, but Mat object will be parallel if SNES object is
2633: Input Parameter:
2634: . snes - the nonlinear solver context
2636: Output Parameters:
2637: + Amat - location to stash (approximate) Jacobian matrix (or NULL)
2638: . Pmat - location to stash matrix used to compute the preconditioner (or NULL)
2639: . J - location to put Jacobian function (or NULL), see SNESJacobianFunction for details on its calling sequence
2640: - ctx - location to stash Jacobian ctx (or NULL)
2642: Level: advanced
2644: .seealso: SNESSetJacobian(), SNESComputeJacobian(), SNESJacobianFunction, SNESGetFunction()
2645: @*/
2646: PetscErrorCode SNESGetJacobian(SNES snes,Mat *Amat,Mat *Pmat,PetscErrorCode (**J)(SNES,Vec,Mat,Mat,void*),void **ctx)
2647: {
2649: DM dm;
2650: DMSNES sdm;
2654: if (Amat) *Amat = snes->jacobian;
2655: if (Pmat) *Pmat = snes->jacobian_pre;
2656: SNESGetDM(snes,&dm);
2657: DMGetDMSNES(dm,&sdm);
2658: if (J) *J = sdm->ops->computejacobian;
2659: if (ctx) *ctx = sdm->jacobianctx;
2660: return(0);
2661: }
2663: /*@
2664: SNESSetUp - Sets up the internal data structures for the later use
2665: of a nonlinear solver.
2667: Collective on SNES
2669: Input Parameters:
2670: . snes - the SNES context
2672: Notes:
2673: For basic use of the SNES solvers the user need not explicitly call
2674: SNESSetUp(), since these actions will automatically occur during
2675: the call to SNESSolve(). However, if one wishes to control this
2676: phase separately, SNESSetUp() should be called after SNESCreate()
2677: and optional routines of the form SNESSetXXX(), but before SNESSolve().
2679: Level: advanced
2681: .keywords: SNES, nonlinear, setup
2683: .seealso: SNESCreate(), SNESSolve(), SNESDestroy()
2684: @*/
2685: PetscErrorCode SNESSetUp(SNES snes)
2686: {
2688: DM dm;
2689: DMSNES sdm;
2690: SNESLineSearch linesearch, pclinesearch;
2691: void *lsprectx,*lspostctx;
2692: PetscErrorCode (*precheck)(SNESLineSearch,Vec,Vec,PetscBool*,void*);
2693: PetscErrorCode (*postcheck)(SNESLineSearch,Vec,Vec,Vec,PetscBool*,PetscBool*,void*);
2694: PetscErrorCode (*func)(SNES,Vec,Vec,void*);
2695: Vec f,fpc;
2696: void *funcctx;
2697: PetscErrorCode (*jac)(SNES,Vec,Mat,Mat,void*);
2698: void *jacctx,*appctx;
2699: Mat j,jpre;
2703: if (snes->setupcalled) return(0);
2705: if (!((PetscObject)snes)->type_name) {
2706: SNESSetType(snes,SNESNEWTONLS);
2707: }
2709: SNESGetFunction(snes,&snes->vec_func,NULL,NULL);
2711: SNESGetDM(snes,&dm);
2712: DMGetDMSNES(dm,&sdm);
2713: if (!sdm->ops->computefunction) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_ARG_WRONGSTATE,"Function never provided to SNES object");
2714: if (!sdm->ops->computejacobian) {
2715: DMSNESSetJacobian(dm,SNESComputeJacobianDefaultColor,NULL);
2716: }
2717: if (!snes->vec_func) {
2718: DMCreateGlobalVector(dm,&snes->vec_func);
2719: }
2721: if (!snes->ksp) {
2722: SNESGetKSP(snes, &snes->ksp);
2723: }
2725: if (!snes->linesearch) {
2726: SNESGetLineSearch(snes, &snes->linesearch);
2727: }
2728: SNESLineSearchSetFunction(snes->linesearch,SNESComputeFunction);
2730: if (snes->npc && (snes->npcside== PC_LEFT)) {
2731: snes->mf = PETSC_TRUE;
2732: snes->mf_operator = PETSC_FALSE;
2733: }
2735: if (snes->npc) {
2736: /* copy the DM over */
2737: SNESGetDM(snes,&dm);
2738: SNESSetDM(snes->npc,dm);
2740: SNESGetFunction(snes,&f,&func,&funcctx);
2741: VecDuplicate(f,&fpc);
2742: SNESSetFunction(snes->npc,fpc,func,funcctx);
2743: SNESGetJacobian(snes,&j,&jpre,&jac,&jacctx);
2744: SNESSetJacobian(snes->npc,j,jpre,jac,jacctx);
2745: SNESGetApplicationContext(snes,&appctx);
2746: SNESSetApplicationContext(snes->npc,appctx);
2747: VecDestroy(&fpc);
2749: /* copy the function pointers over */
2750: PetscObjectCopyFortranFunctionPointers((PetscObject)snes,(PetscObject)snes->npc);
2752: /* default to 1 iteration */
2753: SNESSetTolerances(snes->npc,0.0,0.0,0.0,1,snes->npc->max_funcs);
2754: if (snes->npcside==PC_RIGHT) {
2755: SNESSetNormSchedule(snes->npc,SNES_NORM_FINAL_ONLY);
2756: } else {
2757: SNESSetNormSchedule(snes->npc,SNES_NORM_NONE);
2758: }
2759: SNESSetFromOptions(snes->npc);
2761: /* copy the line search context over */
2762: SNESGetLineSearch(snes,&linesearch);
2763: SNESGetLineSearch(snes->npc,&pclinesearch);
2764: SNESLineSearchGetPreCheck(linesearch,&precheck,&lsprectx);
2765: SNESLineSearchGetPostCheck(linesearch,&postcheck,&lspostctx);
2766: SNESLineSearchSetPreCheck(pclinesearch,precheck,lsprectx);
2767: SNESLineSearchSetPostCheck(pclinesearch,postcheck,lspostctx);
2768: PetscObjectCopyFortranFunctionPointers((PetscObject)linesearch, (PetscObject)pclinesearch);
2769: }
2770: if (snes->mf) {
2771: SNESSetUpMatrixFree_Private(snes, snes->mf_operator, snes->mf_version);
2772: }
2773: if (snes->ops->usercompute && !snes->user) {
2774: (*snes->ops->usercompute)(snes,(void**)&snes->user);
2775: }
2777: snes->jac_iter = 0;
2778: snes->pre_iter = 0;
2780: if (snes->ops->setup) {
2781: (*snes->ops->setup)(snes);
2782: }
2784: if (snes->npc && (snes->npcside== PC_LEFT)) {
2785: if (snes->functype == SNES_FUNCTION_PRECONDITIONED) {
2786: SNESGetLineSearch(snes,&linesearch);
2787: SNESLineSearchSetFunction(linesearch,SNESComputeFunctionDefaultNPC);
2788: }
2789: }
2791: snes->setupcalled = PETSC_TRUE;
2792: return(0);
2793: }
2795: /*@
2796: SNESReset - Resets a SNES context to the snessetupcalled = 0 state and removes any allocated Vecs and Mats
2798: Collective on SNES
2800: Input Parameter:
2801: . snes - iterative context obtained from SNESCreate()
2803: Level: intermediate
2805: Notes: Also calls the application context destroy routine set with SNESSetComputeApplicationContext()
2807: .keywords: SNES, destroy
2809: .seealso: SNESCreate(), SNESSetUp(), SNESSolve()
2810: @*/
2811: PetscErrorCode SNESReset(SNES snes)
2812: {
2817: if (snes->ops->userdestroy && snes->user) {
2818: (*snes->ops->userdestroy)((void**)&snes->user);
2819: snes->user = NULL;
2820: }
2821: if (snes->npc) {
2822: SNESReset(snes->npc);
2823: }
2825: if (snes->ops->reset) {
2826: (*snes->ops->reset)(snes);
2827: }
2828: if (snes->ksp) {
2829: KSPReset(snes->ksp);
2830: }
2832: if (snes->linesearch) {
2833: SNESLineSearchReset(snes->linesearch);
2834: }
2836: VecDestroy(&snes->vec_rhs);
2837: VecDestroy(&snes->vec_sol);
2838: VecDestroy(&snes->vec_sol_update);
2839: VecDestroy(&snes->vec_func);
2840: MatDestroy(&snes->jacobian);
2841: MatDestroy(&snes->jacobian_pre);
2842: VecDestroyVecs(snes->nwork,&snes->work);
2843: VecDestroyVecs(snes->nvwork,&snes->vwork);
2845: snes->alwayscomputesfinalresidual = PETSC_FALSE;
2847: snes->nwork = snes->nvwork = 0;
2848: snes->setupcalled = PETSC_FALSE;
2849: return(0);
2850: }
2852: /*@
2853: SNESDestroy - Destroys the nonlinear solver context that was created
2854: with SNESCreate().
2856: Collective on SNES
2858: Input Parameter:
2859: . snes - the SNES context
2861: Level: beginner
2863: .keywords: SNES, nonlinear, destroy
2865: .seealso: SNESCreate(), SNESSolve()
2866: @*/
2867: PetscErrorCode SNESDestroy(SNES *snes)
2868: {
2872: if (!*snes) return(0);
2874: if (--((PetscObject)(*snes))->refct > 0) {*snes = 0; return(0);}
2876: SNESReset((*snes));
2877: SNESDestroy(&(*snes)->npc);
2879: /* if memory was published with SAWs then destroy it */
2880: PetscObjectSAWsViewOff((PetscObject)*snes);
2881: if ((*snes)->ops->destroy) {(*((*snes))->ops->destroy)((*snes));}
2883: DMDestroy(&(*snes)->dm);
2884: KSPDestroy(&(*snes)->ksp);
2885: SNESLineSearchDestroy(&(*snes)->linesearch);
2887: PetscFree((*snes)->kspconvctx);
2888: if ((*snes)->ops->convergeddestroy) {
2889: (*(*snes)->ops->convergeddestroy)((*snes)->cnvP);
2890: }
2891: if ((*snes)->conv_malloc) {
2892: PetscFree((*snes)->conv_hist);
2893: PetscFree((*snes)->conv_hist_its);
2894: }
2895: SNESMonitorCancel((*snes));
2896: PetscHeaderDestroy(snes);
2897: return(0);
2898: }
2900: /* ----------- Routines to set solver parameters ---------- */
2902: /*@
2903: SNESSetLagPreconditioner - Determines when the preconditioner is rebuilt in the nonlinear solve.
2905: Logically Collective on SNES
2907: Input Parameters:
2908: + snes - the SNES context
2909: - lag - -1 indicates NEVER rebuild, 1 means rebuild every time the Jacobian is computed within a single nonlinear solve, 2 means every second time
2910: the Jacobian is built etc. -2 indicates rebuild preconditioner at next chance but then never rebuild after that
2912: Options Database Keys:
2913: . -snes_lag_preconditioner <lag>
2915: Notes:
2916: The default is 1
2917: The preconditioner is ALWAYS built in the first iteration of a nonlinear solve unless lag is -1
2918: If -1 is used before the very first nonlinear solve the preconditioner is still built because there is no previous preconditioner to use
2920: Level: intermediate
2922: .keywords: SNES, nonlinear, set, convergence, tolerances
2924: .seealso: SNESSetTrustRegionTolerance(), SNESGetLagPreconditioner(), SNESSetLagJacobian(), SNESGetLagJacobian()
2926: @*/
2927: PetscErrorCode SNESSetLagPreconditioner(SNES snes,PetscInt lag)
2928: {
2931: if (lag < -2) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Lag must be -2, -1, 1 or greater");
2932: if (!lag) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Lag cannot be 0");
2934: snes->lagpreconditioner = lag;
2935: return(0);
2936: }
2938: /*@
2939: SNESSetGridSequence - sets the number of steps of grid sequencing that SNES does
2941: Logically Collective on SNES
2943: Input Parameters:
2944: + snes - the SNES context
2945: - steps - the number of refinements to do, defaults to 0
2947: Options Database Keys:
2948: . -snes_grid_sequence <steps>
2950: Level: intermediate
2952: Notes:
2953: Use SNESGetSolution() to extract the fine grid solution after grid sequencing.
2955: .keywords: SNES, nonlinear, set, convergence, tolerances
2957: .seealso: SNESSetTrustRegionTolerance(), SNESGetLagPreconditioner(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESGetGridSequence()
2959: @*/
2960: PetscErrorCode SNESSetGridSequence(SNES snes,PetscInt steps)
2961: {
2965: snes->gridsequence = steps;
2966: return(0);
2967: }
2969: /*@
2970: SNESGetGridSequence - gets the number of steps of grid sequencing that SNES does
2972: Logically Collective on SNES
2974: Input Parameter:
2975: . snes - the SNES context
2977: Output Parameter:
2978: . steps - the number of refinements to do, defaults to 0
2980: Options Database Keys:
2981: . -snes_grid_sequence <steps>
2983: Level: intermediate
2985: Notes:
2986: Use SNESGetSolution() to extract the fine grid solution after grid sequencing.
2988: .keywords: SNES, nonlinear, set, convergence, tolerances
2990: .seealso: SNESSetTrustRegionTolerance(), SNESGetLagPreconditioner(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESSetGridSequence()
2992: @*/
2993: PetscErrorCode SNESGetGridSequence(SNES snes,PetscInt *steps)
2994: {
2997: *steps = snes->gridsequence;
2998: return(0);
2999: }
3001: /*@
3002: SNESGetLagPreconditioner - Indicates how often the preconditioner is rebuilt
3004: Not Collective
3006: Input Parameter:
3007: . snes - the SNES context
3009: Output Parameter:
3010: . lag - -1 indicates NEVER rebuild, 1 means rebuild every time the Jacobian is computed within a single nonlinear solve, 2 means every second time
3011: the Jacobian is built etc. -2 indicates rebuild preconditioner at next chance but then never rebuild after that
3013: Options Database Keys:
3014: . -snes_lag_preconditioner <lag>
3016: Notes:
3017: The default is 1
3018: The preconditioner is ALWAYS built in the first iteration of a nonlinear solve unless lag is -1
3020: Level: intermediate
3022: .keywords: SNES, nonlinear, set, convergence, tolerances
3024: .seealso: SNESSetTrustRegionTolerance(), SNESSetLagPreconditioner()
3026: @*/
3027: PetscErrorCode SNESGetLagPreconditioner(SNES snes,PetscInt *lag)
3028: {
3031: *lag = snes->lagpreconditioner;
3032: return(0);
3033: }
3035: /*@
3036: SNESSetLagJacobian - Determines when the Jacobian is rebuilt in the nonlinear solve. See SNESSetLagPreconditioner() for determining how
3037: often the preconditioner is rebuilt.
3039: Logically Collective on SNES
3041: Input Parameters:
3042: + snes - the SNES context
3043: - lag - -1 indicates NEVER rebuild, 1 means rebuild every time the Jacobian is computed within a single nonlinear solve, 2 means every second time
3044: the Jacobian is built etc. -2 means rebuild at next chance but then never again
3046: Options Database Keys:
3047: . -snes_lag_jacobian <lag>
3049: Notes:
3050: The default is 1
3051: The Jacobian is ALWAYS built in the first iteration of a nonlinear solve unless lag is -1
3052: 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
3053: at the next Newton step but never again (unless it is reset to another value)
3055: Level: intermediate
3057: .keywords: SNES, nonlinear, set, convergence, tolerances
3059: .seealso: SNESSetTrustRegionTolerance(), SNESGetLagPreconditioner(), SNESSetLagPreconditioner(), SNESGetLagJacobian()
3061: @*/
3062: PetscErrorCode SNESSetLagJacobian(SNES snes,PetscInt lag)
3063: {
3066: if (lag < -2) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Lag must be -2, -1, 1 or greater");
3067: if (!lag) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Lag cannot be 0");
3069: snes->lagjacobian = lag;
3070: return(0);
3071: }
3073: /*@
3074: SNESGetLagJacobian - Indicates how often the Jacobian is rebuilt. See SNESGetLagPreconditioner() to determine when the preconditioner is rebuilt
3076: Not Collective
3078: Input Parameter:
3079: . snes - the SNES context
3081: Output Parameter:
3082: . lag - -1 indicates NEVER rebuild, 1 means rebuild every time the Jacobian is computed within a single nonlinear solve, 2 means every second time
3083: the Jacobian is built etc.
3085: Options Database Keys:
3086: . -snes_lag_jacobian <lag>
3088: Notes:
3089: The default is 1
3090: The jacobian is ALWAYS built in the first iteration of a nonlinear solve unless lag is -1
3092: Level: intermediate
3094: .keywords: SNES, nonlinear, set, convergence, tolerances
3096: .seealso: SNESSetTrustRegionTolerance(), SNESSetLagJacobian(), SNESSetLagPreconditioner(), SNESGetLagPreconditioner()
3098: @*/
3099: PetscErrorCode SNESGetLagJacobian(SNES snes,PetscInt *lag)
3100: {
3103: *lag = snes->lagjacobian;
3104: return(0);
3105: }
3107: /*@
3108: SNESSetLagJacobianPersists - Set whether or not the Jacobian lagging persists through multiple solves
3110: Logically collective on SNES
3112: Input Parameter:
3113: + snes - the SNES context
3114: - flg - jacobian lagging persists if true
3116: Options Database Keys:
3117: . -snes_lag_jacobian_persists <flg>
3119: Notes: This is useful both for nonlinear preconditioning, where it's appropriate to have the Jacobian be stale by
3120: several solves, and for implicit time-stepping, where Jacobian lagging in the inner nonlinear solve over several
3121: timesteps may present huge efficiency gains.
3123: Level: developer
3125: .keywords: SNES, nonlinear, lag
3127: .seealso: SNESSetLagPreconditionerPersists(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESGetNPC()
3129: @*/
3130: PetscErrorCode SNESSetLagJacobianPersists(SNES snes,PetscBool flg)
3131: {
3135: snes->lagjac_persist = flg;
3136: return(0);
3137: }
3139: /*@
3140: SNESSetLagPreconditionerPersists - Set whether or not the preconditioner lagging persists through multiple solves
3142: Logically Collective on SNES
3144: Input Parameter:
3145: + snes - the SNES context
3146: - flg - preconditioner lagging persists if true
3148: Options Database Keys:
3149: . -snes_lag_jacobian_persists <flg>
3151: Notes: This is useful both for nonlinear preconditioning, where it's appropriate to have the preconditioner be stale
3152: by several solves, and for implicit time-stepping, where preconditioner lagging in the inner nonlinear solve over
3153: several timesteps may present huge efficiency gains.
3155: Level: developer
3157: .keywords: SNES, nonlinear, lag
3159: .seealso: SNESSetLagJacobianPersists(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESGetNPC()
3161: @*/
3162: PetscErrorCode SNESSetLagPreconditionerPersists(SNES snes,PetscBool flg)
3163: {
3167: snes->lagpre_persist = flg;
3168: return(0);
3169: }
3171: /*@
3172: SNESSetForceIteration - force SNESSolve() to take at least one iteration regardless of the initial residual norm
3174: Logically Collective on SNES
3176: Input Parameters:
3177: + snes - the SNES context
3178: - force - PETSC_TRUE require at least one iteration
3180: Options Database Keys:
3181: . -snes_force_iteration <force> - Sets forcing an iteration
3183: Notes:
3184: This is used sometimes with TS to prevent TS from detecting a false steady state solution
3186: Level: intermediate
3188: .keywords: SNES, nonlinear, set, convergence, tolerances
3190: .seealso: SNESSetTrustRegionTolerance(), SNESSetDivergenceTolerance()
3191: @*/
3192: PetscErrorCode SNESSetForceIteration(SNES snes,PetscBool force)
3193: {
3196: snes->forceiteration = force;
3197: return(0);
3198: }
3201: /*@
3202: SNESSetTolerances - Sets various parameters used in convergence tests.
3204: Logically Collective on SNES
3206: Input Parameters:
3207: + snes - the SNES context
3208: . abstol - absolute convergence tolerance
3209: . rtol - relative convergence tolerance
3210: . stol - convergence tolerance in terms of the norm of the change in the solution between steps, || delta x || < stol*|| x ||
3211: . maxit - maximum number of iterations
3212: - maxf - maximum number of function evaluations
3214: Options Database Keys:
3215: + -snes_atol <abstol> - Sets abstol
3216: . -snes_rtol <rtol> - Sets rtol
3217: . -snes_stol <stol> - Sets stol
3218: . -snes_max_it <maxit> - Sets maxit
3219: - -snes_max_funcs <maxf> - Sets maxf
3221: Notes:
3222: The default maximum number of iterations is 50.
3223: The default maximum number of function evaluations is 1000.
3225: Level: intermediate
3227: .keywords: SNES, nonlinear, set, convergence, tolerances
3229: .seealso: SNESSetTrustRegionTolerance(), SNESSetDivergenceTolerance(), SNESSetForceIteration()
3230: @*/
3231: PetscErrorCode SNESSetTolerances(SNES snes,PetscReal abstol,PetscReal rtol,PetscReal stol,PetscInt maxit,PetscInt maxf)
3232: {
3241: if (abstol != PETSC_DEFAULT) {
3242: if (abstol < 0.0) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Absolute tolerance %g must be non-negative",(double)abstol);
3243: snes->abstol = abstol;
3244: }
3245: if (rtol != PETSC_DEFAULT) {
3246: 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);
3247: snes->rtol = rtol;
3248: }
3249: if (stol != PETSC_DEFAULT) {
3250: if (stol < 0.0) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Step tolerance %g must be non-negative",(double)stol);
3251: snes->stol = stol;
3252: }
3253: if (maxit != PETSC_DEFAULT) {
3254: if (maxit < 0) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Maximum number of iterations %D must be non-negative",maxit);
3255: snes->max_its = maxit;
3256: }
3257: if (maxf != PETSC_DEFAULT) {
3258: if (maxf < 0) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Maximum number of function evaluations %D must be non-negative",maxf);
3259: snes->max_funcs = maxf;
3260: }
3261: snes->tolerancesset = PETSC_TRUE;
3262: return(0);
3263: }
3265: /*@
3266: SNESSetDivergenceTolerance - Sets the divergence tolerance used for the SNES divergence test.
3268: Logically Collective on SNES
3270: Input Parameters:
3271: + snes - the SNES context
3272: - divtol - the divergence tolerance. Use -1 to deactivate the test.
3274: Options Database Keys:
3275: + -snes_divergence_tolerance <divtol> - Sets divtol
3277: Notes:
3278: The default divergence tolerance is 1e4.
3280: Level: intermediate
3282: .keywords: SNES, nonlinear, set, divergence, tolerance
3284: .seealso: SNESSetTolerances(), SNESGetDivergenceTolerance
3285: @*/
3286: PetscErrorCode SNESSetDivergenceTolerance(SNES snes,PetscReal divtol)
3287: {
3292: if (divtol != PETSC_DEFAULT) {
3293: snes->divtol = divtol;
3294: }
3295: else {
3296: snes->divtol = 1.0e4;
3297: }
3298: return(0);
3299: }
3301: /*@
3302: SNESGetTolerances - Gets various parameters used in convergence tests.
3304: Not Collective
3306: Input Parameters:
3307: + snes - the SNES context
3308: . atol - absolute convergence tolerance
3309: . rtol - relative convergence tolerance
3310: . stol - convergence tolerance in terms of the norm
3311: of the change in the solution between steps
3312: . maxit - maximum number of iterations
3313: - maxf - maximum number of function evaluations
3315: Notes:
3316: The user can specify NULL for any parameter that is not needed.
3318: Level: intermediate
3320: .keywords: SNES, nonlinear, get, convergence, tolerances
3322: .seealso: SNESSetTolerances()
3323: @*/
3324: PetscErrorCode SNESGetTolerances(SNES snes,PetscReal *atol,PetscReal *rtol,PetscReal *stol,PetscInt *maxit,PetscInt *maxf)
3325: {
3328: if (atol) *atol = snes->abstol;
3329: if (rtol) *rtol = snes->rtol;
3330: if (stol) *stol = snes->stol;
3331: if (maxit) *maxit = snes->max_its;
3332: if (maxf) *maxf = snes->max_funcs;
3333: return(0);
3334: }
3336: /*@
3337: SNESGetDivergenceTolerance - Gets divergence tolerance used in divergence test.
3339: Not Collective
3341: Input Parameters:
3342: + snes - the SNES context
3343: - divtol - divergence tolerance
3345: Level: intermediate
3347: .keywords: SNES, nonlinear, get, divergence, tolerance
3349: .seealso: SNESSetDivergenceTolerance()
3350: @*/
3351: PetscErrorCode SNESGetDivergenceTolerance(SNES snes,PetscReal *divtol)
3352: {
3355: if (divtol) *divtol = snes->divtol;
3356: return(0);
3357: }
3359: /*@
3360: SNESSetTrustRegionTolerance - Sets the trust region parameter tolerance.
3362: Logically Collective on SNES
3364: Input Parameters:
3365: + snes - the SNES context
3366: - tol - tolerance
3368: Options Database Key:
3369: . -snes_trtol <tol> - Sets tol
3371: Level: intermediate
3373: .keywords: SNES, nonlinear, set, trust region, tolerance
3375: .seealso: SNESSetTolerances()
3376: @*/
3377: PetscErrorCode SNESSetTrustRegionTolerance(SNES snes,PetscReal tol)
3378: {
3382: snes->deltatol = tol;
3383: return(0);
3384: }
3386: /*
3387: Duplicate the lg monitors for SNES from KSP; for some reason with
3388: dynamic libraries things don't work under Sun4 if we just use
3389: macros instead of functions
3390: */
3391: PetscErrorCode SNESMonitorLGResidualNorm(SNES snes,PetscInt it,PetscReal norm,void *ctx)
3392: {
3397: KSPMonitorLGResidualNorm((KSP)snes,it,norm,ctx);
3398: return(0);
3399: }
3401: PetscErrorCode SNESMonitorLGCreate(MPI_Comm comm,const char host[],const char label[],int x,int y,int m,int n,PetscDrawLG *lgctx)
3402: {
3406: KSPMonitorLGResidualNormCreate(comm,host,label,x,y,m,n,lgctx);
3407: return(0);
3408: }
3410: PETSC_INTERN PetscErrorCode SNESMonitorRange_Private(SNES,PetscInt,PetscReal*);
3412: PetscErrorCode SNESMonitorLGRange(SNES snes,PetscInt n,PetscReal rnorm,void *monctx)
3413: {
3414: PetscDrawLG lg;
3415: PetscErrorCode ierr;
3416: PetscReal x,y,per;
3417: PetscViewer v = (PetscViewer)monctx;
3418: static PetscReal prev; /* should be in the context */
3419: PetscDraw draw;
3423: PetscViewerDrawGetDrawLG(v,0,&lg);
3424: if (!n) {PetscDrawLGReset(lg);}
3425: PetscDrawLGGetDraw(lg,&draw);
3426: PetscDrawSetTitle(draw,"Residual norm");
3427: x = (PetscReal)n;
3428: if (rnorm > 0.0) y = PetscLog10Real(rnorm);
3429: else y = -15.0;
3430: PetscDrawLGAddPoint(lg,&x,&y);
3431: if (n < 20 || !(n % 5) || snes->reason) {
3432: PetscDrawLGDraw(lg);
3433: PetscDrawLGSave(lg);
3434: }
3436: PetscViewerDrawGetDrawLG(v,1,&lg);
3437: if (!n) {PetscDrawLGReset(lg);}
3438: PetscDrawLGGetDraw(lg,&draw);
3439: PetscDrawSetTitle(draw,"% elemts > .2*max elemt");
3440: SNESMonitorRange_Private(snes,n,&per);
3441: x = (PetscReal)n;
3442: y = 100.0*per;
3443: PetscDrawLGAddPoint(lg,&x,&y);
3444: if (n < 20 || !(n % 5) || snes->reason) {
3445: PetscDrawLGDraw(lg);
3446: PetscDrawLGSave(lg);
3447: }
3449: PetscViewerDrawGetDrawLG(v,2,&lg);
3450: if (!n) {prev = rnorm;PetscDrawLGReset(lg);}
3451: PetscDrawLGGetDraw(lg,&draw);
3452: PetscDrawSetTitle(draw,"(norm -oldnorm)/oldnorm");
3453: x = (PetscReal)n;
3454: y = (prev - rnorm)/prev;
3455: PetscDrawLGAddPoint(lg,&x,&y);
3456: if (n < 20 || !(n % 5) || snes->reason) {
3457: PetscDrawLGDraw(lg);
3458: PetscDrawLGSave(lg);
3459: }
3461: PetscViewerDrawGetDrawLG(v,3,&lg);
3462: if (!n) {PetscDrawLGReset(lg);}
3463: PetscDrawLGGetDraw(lg,&draw);
3464: PetscDrawSetTitle(draw,"(norm -oldnorm)/oldnorm*(% > .2 max)");
3465: x = (PetscReal)n;
3466: y = (prev - rnorm)/(prev*per);
3467: if (n > 2) { /*skip initial crazy value */
3468: PetscDrawLGAddPoint(lg,&x,&y);
3469: }
3470: if (n < 20 || !(n % 5) || snes->reason) {
3471: PetscDrawLGDraw(lg);
3472: PetscDrawLGSave(lg);
3473: }
3474: prev = rnorm;
3475: return(0);
3476: }
3478: /*@
3479: SNESMonitor - runs the user provided monitor routines, if they exist
3481: Collective on SNES
3483: Input Parameters:
3484: + snes - nonlinear solver context obtained from SNESCreate()
3485: . iter - iteration number
3486: - rnorm - relative norm of the residual
3488: Notes:
3489: This routine is called by the SNES implementations.
3490: It does not typically need to be called by the user.
3492: Level: developer
3494: .seealso: SNESMonitorSet()
3495: @*/
3496: PetscErrorCode SNESMonitor(SNES snes,PetscInt iter,PetscReal rnorm)
3497: {
3499: PetscInt i,n = snes->numbermonitors;
3502: VecLockPush(snes->vec_sol);
3503: for (i=0; i<n; i++) {
3504: (*snes->monitor[i])(snes,iter,rnorm,snes->monitorcontext[i]);
3505: }
3506: VecLockPop(snes->vec_sol);
3507: return(0);
3508: }
3510: /* ------------ Routines to set performance monitoring options ----------- */
3512: /*MC
3513: SNESMonitorFunction - functional form passed to SNESMonitorSet() to monitor convergence of nonlinear solver
3515: Synopsis:
3516: #include <petscsnes.h>
3517: $ PetscErrorCode SNESMonitorFunction(SNES snes,PetscInt its, PetscReal norm,void *mctx)
3519: + snes - the SNES context
3520: . its - iteration number
3521: . norm - 2-norm function value (may be estimated)
3522: - mctx - [optional] monitoring context
3524: Level: advanced
3526: .seealso: SNESMonitorSet(), SNESMonitorGet()
3527: M*/
3529: /*@C
3530: SNESMonitorSet - Sets an ADDITIONAL function that is to be used at every
3531: iteration of the nonlinear solver to display the iteration's
3532: progress.
3534: Logically Collective on SNES
3536: Input Parameters:
3537: + snes - the SNES context
3538: . f - the monitor function, see SNESMonitorFunction for the calling sequence
3539: . mctx - [optional] user-defined context for private data for the
3540: monitor routine (use NULL if no context is desired)
3541: - monitordestroy - [optional] routine that frees monitor context
3542: (may be NULL)
3544: Options Database Keys:
3545: + -snes_monitor - sets SNESMonitorDefault()
3546: . -snes_monitor_lg_residualnorm - sets line graph monitor,
3547: uses SNESMonitorLGCreate()
3548: - -snes_monitor_cancel - cancels all monitors that have
3549: been hardwired into a code by
3550: calls to SNESMonitorSet(), but
3551: does not cancel those set via
3552: the options database.
3554: Notes:
3555: Several different monitoring routines may be set by calling
3556: SNESMonitorSet() multiple times; all will be called in the
3557: order in which they were set.
3559: Fortran notes: Only a single monitor function can be set for each SNES object
3561: Level: intermediate
3563: .keywords: SNES, nonlinear, set, monitor
3565: .seealso: SNESMonitorDefault(), SNESMonitorCancel(), SNESMonitorFunction
3566: @*/
3567: PetscErrorCode SNESMonitorSet(SNES snes,PetscErrorCode (*f)(SNES,PetscInt,PetscReal,void*),void *mctx,PetscErrorCode (*monitordestroy)(void**))
3568: {
3569: PetscInt i;
3571: PetscBool identical;
3575: for (i=0; i<snes->numbermonitors;i++) {
3576: PetscMonitorCompare((PetscErrorCode (*)(void))f,mctx,monitordestroy,(PetscErrorCode (*)(void))snes->monitor[i],snes->monitorcontext[i],snes->monitordestroy[i],&identical);
3577: if (identical) return(0);
3578: }
3579: if (snes->numbermonitors >= MAXSNESMONITORS) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Too many monitors set");
3580: snes->monitor[snes->numbermonitors] = f;
3581: snes->monitordestroy[snes->numbermonitors] = monitordestroy;
3582: snes->monitorcontext[snes->numbermonitors++] = (void*)mctx;
3583: return(0);
3584: }
3586: /*@
3587: SNESMonitorCancel - Clears all the monitor functions for a SNES object.
3589: Logically Collective on SNES
3591: Input Parameters:
3592: . snes - the SNES context
3594: Options Database Key:
3595: . -snes_monitor_cancel - cancels all monitors that have been hardwired
3596: into a code by calls to SNESMonitorSet(), but does not cancel those
3597: set via the options database
3599: Notes:
3600: There is no way to clear one specific monitor from a SNES object.
3602: Level: intermediate
3604: .keywords: SNES, nonlinear, set, monitor
3606: .seealso: SNESMonitorDefault(), SNESMonitorSet()
3607: @*/
3608: PetscErrorCode SNESMonitorCancel(SNES snes)
3609: {
3611: PetscInt i;
3615: for (i=0; i<snes->numbermonitors; i++) {
3616: if (snes->monitordestroy[i]) {
3617: (*snes->monitordestroy[i])(&snes->monitorcontext[i]);
3618: }
3619: }
3620: snes->numbermonitors = 0;
3621: return(0);
3622: }
3624: /*MC
3625: SNESConvergenceTestFunction - functional form used for testing of convergence of nonlinear solver
3627: Synopsis:
3628: #include <petscsnes.h>
3629: $ PetscErrorCode SNESConvergenceTest(SNES snes,PetscInt it,PetscReal xnorm,PetscReal gnorm,PetscReal f,SNESConvergedReason *reason,void *cctx)
3631: + snes - the SNES context
3632: . it - current iteration (0 is the first and is before any Newton step)
3633: . cctx - [optional] convergence context
3634: . reason - reason for convergence/divergence
3635: . xnorm - 2-norm of current iterate
3636: . gnorm - 2-norm of current step
3637: - f - 2-norm of function
3639: Level: intermediate
3641: .seealso: SNESSetConvergenceTest(), SNESGetConvergenceTest()
3642: M*/
3644: /*@C
3645: SNESSetConvergenceTest - Sets the function that is to be used
3646: to test for convergence of the nonlinear iterative solution.
3648: Logically Collective on SNES
3650: Input Parameters:
3651: + snes - the SNES context
3652: . SNESConvergenceTestFunction - routine to test for convergence
3653: . cctx - [optional] context for private data for the convergence routine (may be NULL)
3654: - destroy - [optional] destructor for the context (may be NULL; NULL_FUNCTION in Fortran)
3656: Level: advanced
3658: .keywords: SNES, nonlinear, set, convergence, test
3660: .seealso: SNESConvergedDefault(), SNESConvergedSkip(), SNESConvergenceTestFunction
3661: @*/
3662: PetscErrorCode SNESSetConvergenceTest(SNES snes,PetscErrorCode (*SNESConvergenceTestFunction)(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*),void *cctx,PetscErrorCode (*destroy)(void*))
3663: {
3668: if (!SNESConvergenceTestFunction) SNESConvergenceTestFunction = SNESConvergedSkip;
3669: if (snes->ops->convergeddestroy) {
3670: (*snes->ops->convergeddestroy)(snes->cnvP);
3671: }
3672: snes->ops->converged = SNESConvergenceTestFunction;
3673: snes->ops->convergeddestroy = destroy;
3674: snes->cnvP = cctx;
3675: return(0);
3676: }
3678: /*@
3679: SNESGetConvergedReason - Gets the reason the SNES iteration was stopped.
3681: Not Collective
3683: Input Parameter:
3684: . snes - the SNES context
3686: Output Parameter:
3687: . reason - negative value indicates diverged, positive value converged, see SNESConvergedReason or the
3688: manual pages for the individual convergence tests for complete lists
3690: Options Database:
3691: . -snes_converged_reason - prints the reason to standard out
3693: Level: intermediate
3695: Notes: Should only be called after the call the SNESSolve() is complete, if it is called earlier it returns the value SNES__CONVERGED_ITERATING.
3697: .keywords: SNES, nonlinear, set, convergence, test
3699: .seealso: SNESSetConvergenceTest(), SNESSetConvergedReason(), SNESConvergedReason
3700: @*/
3701: PetscErrorCode SNESGetConvergedReason(SNES snes,SNESConvergedReason *reason)
3702: {
3706: *reason = snes->reason;
3707: return(0);
3708: }
3710: /*@
3711: SNESSetConvergedReason - Sets the reason the SNES iteration was stopped.
3713: Not Collective
3715: Input Parameters:
3716: + snes - the SNES context
3717: - reason - negative value indicates diverged, positive value converged, see SNESConvergedReason or the
3718: manual pages for the individual convergence tests for complete lists
3720: Level: intermediate
3722: .keywords: SNES, nonlinear, set, convergence, test
3723: .seealso: SNESGetConvergedReason(), SNESSetConvergenceTest(), SNESConvergedReason
3724: @*/
3725: PetscErrorCode SNESSetConvergedReason(SNES snes,SNESConvergedReason reason)
3726: {
3729: snes->reason = reason;
3730: return(0);
3731: }
3733: /*@
3734: SNESSetConvergenceHistory - Sets the array used to hold the convergence history.
3736: Logically Collective on SNES
3738: Input Parameters:
3739: + snes - iterative context obtained from SNESCreate()
3740: . a - array to hold history, this array will contain the function norms computed at each step
3741: . its - integer array holds the number of linear iterations for each solve.
3742: . na - size of a and its
3743: - reset - PETSC_TRUE indicates each new nonlinear solve resets the history counter to zero,
3744: else it continues storing new values for new nonlinear solves after the old ones
3746: Notes:
3747: If 'a' and 'its' are NULL then space is allocated for the history. If 'na' PETSC_DECIDE or PETSC_DEFAULT then a
3748: default array of length 10000 is allocated.
3750: This routine is useful, e.g., when running a code for purposes
3751: of accurate performance monitoring, when no I/O should be done
3752: during the section of code that is being timed.
3754: Level: intermediate
3756: .keywords: SNES, set, convergence, history
3758: .seealso: SNESGetConvergenceHistory()
3760: @*/
3761: PetscErrorCode SNESSetConvergenceHistory(SNES snes,PetscReal a[],PetscInt its[],PetscInt na,PetscBool reset)
3762: {
3769: if (!a) {
3770: if (na == PETSC_DECIDE || na == PETSC_DEFAULT) na = 1000;
3771: PetscCalloc1(na,&a);
3772: PetscCalloc1(na,&its);
3774: snes->conv_malloc = PETSC_TRUE;
3775: }
3776: snes->conv_hist = a;
3777: snes->conv_hist_its = its;
3778: snes->conv_hist_max = na;
3779: snes->conv_hist_len = 0;
3780: snes->conv_hist_reset = reset;
3781: return(0);
3782: }
3784: #if defined(PETSC_HAVE_MATLAB_ENGINE)
3785: #include <engine.h> /* MATLAB include file */
3786: #include <mex.h> /* MATLAB include file */
3788: PETSC_EXTERN mxArray *SNESGetConvergenceHistoryMatlab(SNES snes)
3789: {
3790: mxArray *mat;
3791: PetscInt i;
3792: PetscReal *ar;
3795: mat = mxCreateDoubleMatrix(snes->conv_hist_len,1,mxREAL);
3796: ar = (PetscReal*) mxGetData(mat);
3797: for (i=0; i<snes->conv_hist_len; i++) ar[i] = snes->conv_hist[i];
3798: PetscFunctionReturn(mat);
3799: }
3800: #endif
3802: /*@C
3803: SNESGetConvergenceHistory - Gets the array used to hold the convergence history.
3805: Not Collective
3807: Input Parameter:
3808: . snes - iterative context obtained from SNESCreate()
3810: Output Parameters:
3811: . a - array to hold history
3812: . its - integer array holds the number of linear iterations (or
3813: negative if not converged) for each solve.
3814: - na - size of a and its
3816: Notes:
3817: The calling sequence for this routine in Fortran is
3818: $ call SNESGetConvergenceHistory(SNES snes, integer na, integer ierr)
3820: This routine is useful, e.g., when running a code for purposes
3821: of accurate performance monitoring, when no I/O should be done
3822: during the section of code that is being timed.
3824: Level: intermediate
3826: .keywords: SNES, get, convergence, history
3828: .seealso: SNESSetConvergencHistory()
3830: @*/
3831: PetscErrorCode SNESGetConvergenceHistory(SNES snes,PetscReal *a[],PetscInt *its[],PetscInt *na)
3832: {
3835: if (a) *a = snes->conv_hist;
3836: if (its) *its = snes->conv_hist_its;
3837: if (na) *na = snes->conv_hist_len;
3838: return(0);
3839: }
3841: /*@C
3842: SNESSetUpdate - Sets the general-purpose update function called
3843: at the beginning of every iteration of the nonlinear solve. Specifically
3844: it is called just before the Jacobian is "evaluated".
3846: Logically Collective on SNES
3848: Input Parameters:
3849: . snes - The nonlinear solver context
3850: . func - The function
3852: Calling sequence of func:
3853: . func (SNES snes, PetscInt step);
3855: . step - The current step of the iteration
3857: Level: advanced
3859: 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()
3860: This is not used by most users.
3862: .keywords: SNES, update
3864: .seealso SNESSetJacobian(), SNESSolve()
3865: @*/
3866: PetscErrorCode SNESSetUpdate(SNES snes, PetscErrorCode (*func)(SNES, PetscInt))
3867: {
3870: snes->ops->update = func;
3871: return(0);
3872: }
3874: /*
3875: SNESScaleStep_Private - Scales a step so that its length is less than the
3876: positive parameter delta.
3878: Input Parameters:
3879: + snes - the SNES context
3880: . y - approximate solution of linear system
3881: . fnorm - 2-norm of current function
3882: - delta - trust region size
3884: Output Parameters:
3885: + gpnorm - predicted function norm at the new point, assuming local
3886: linearization. The value is zero if the step lies within the trust
3887: region, and exceeds zero otherwise.
3888: - ynorm - 2-norm of the step
3890: Note:
3891: For non-trust region methods such as SNESNEWTONLS, the parameter delta
3892: is set to be the maximum allowable step size.
3894: .keywords: SNES, nonlinear, scale, step
3895: */
3896: PetscErrorCode SNESScaleStep_Private(SNES snes,Vec y,PetscReal *fnorm,PetscReal *delta,PetscReal *gpnorm,PetscReal *ynorm)
3897: {
3898: PetscReal nrm;
3899: PetscScalar cnorm;
3907: VecNorm(y,NORM_2,&nrm);
3908: if (nrm > *delta) {
3909: nrm = *delta/nrm;
3910: *gpnorm = (1.0 - nrm)*(*fnorm);
3911: cnorm = nrm;
3912: VecScale(y,cnorm);
3913: *ynorm = *delta;
3914: } else {
3915: *gpnorm = 0.0;
3916: *ynorm = nrm;
3917: }
3918: return(0);
3919: }
3921: /*@
3922: SNESReasonView - Displays the reason a SNES solve converged or diverged to a viewer
3924: Collective on SNES
3926: Parameter:
3927: + snes - iterative context obtained from SNESCreate()
3928: - viewer - the viewer to display the reason
3931: Options Database Keys:
3932: . -snes_converged_reason - print reason for converged or diverged, also prints number of iterations
3934: Level: beginner
3936: .keywords: SNES, solve, linear system
3938: .seealso: SNESCreate(), SNESSetUp(), SNESDestroy(), SNESSetTolerances(), SNESConvergedDefault()
3940: @*/
3941: PetscErrorCode SNESReasonView(SNES snes,PetscViewer viewer)
3942: {
3944: PetscBool isAscii;
3947: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&isAscii);
3948: if (isAscii) {
3949: PetscViewerASCIIAddTab(viewer,((PetscObject)snes)->tablevel);
3950: if (snes->reason > 0) {
3951: if (((PetscObject) snes)->prefix) {
3952: PetscViewerASCIIPrintf(viewer,"Nonlinear %s solve converged due to %s iterations %D\n",((PetscObject) snes)->prefix,SNESConvergedReasons[snes->reason],snes->iter);
3953: } else {
3954: PetscViewerASCIIPrintf(viewer,"Nonlinear solve converged due to %s iterations %D\n",SNESConvergedReasons[snes->reason],snes->iter);
3955: }
3956: } else {
3957: if (((PetscObject) snes)->prefix) {
3958: PetscViewerASCIIPrintf(viewer,"Nonlinear %s solve did not converge due to %s iterations %D\n",((PetscObject) snes)->prefix,SNESConvergedReasons[snes->reason],snes->iter);
3959: } else {
3960: PetscViewerASCIIPrintf(viewer,"Nonlinear solve did not converge due to %s iterations %D\n",SNESConvergedReasons[snes->reason],snes->iter);
3961: }
3962: }
3963: PetscViewerASCIISubtractTab(viewer,((PetscObject)snes)->tablevel);
3964: }
3965: return(0);
3966: }
3968: /*@C
3969: SNESReasonViewFromOptions - Processes command line options to determine if/how a SNESReason is to be viewed.
3971: Collective on SNES
3973: Input Parameters:
3974: . snes - the SNES object
3976: Level: intermediate
3978: @*/
3979: PetscErrorCode SNESReasonViewFromOptions(SNES snes)
3980: {
3981: PetscErrorCode ierr;
3982: PetscViewer viewer;
3983: PetscBool flg;
3984: static PetscBool incall = PETSC_FALSE;
3985: PetscViewerFormat format;
3988: if (incall) return(0);
3989: incall = PETSC_TRUE;
3990: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_converged_reason",&viewer,&format,&flg);
3991: if (flg) {
3992: PetscViewerPushFormat(viewer,format);
3993: SNESReasonView(snes,viewer);
3994: PetscViewerPopFormat(viewer);
3995: PetscViewerDestroy(&viewer);
3996: }
3997: incall = PETSC_FALSE;
3998: return(0);
3999: }
4001: /*@C
4002: SNESSolve - Solves a nonlinear system F(x) = b.
4003: Call SNESSolve() after calling SNESCreate() and optional routines of the form SNESSetXXX().
4005: Collective on SNES
4007: Input Parameters:
4008: + snes - the SNES context
4009: . b - the constant part of the equation F(x) = b, or NULL to use zero.
4010: - x - the solution vector.
4012: Notes:
4013: The user should initialize the vector,x, with the initial guess
4014: for the nonlinear solve prior to calling SNESSolve. In particular,
4015: to employ an initial guess of zero, the user should explicitly set
4016: this vector to zero by calling VecSet().
4018: Level: beginner
4020: .keywords: SNES, nonlinear, solve
4022: .seealso: SNESCreate(), SNESDestroy(), SNESSetFunction(), SNESSetJacobian(), SNESSetGridSequence(), SNESGetSolution()
4023: @*/
4024: PetscErrorCode SNESSolve(SNES snes,Vec b,Vec x)
4025: {
4026: PetscErrorCode ierr;
4027: PetscBool flg;
4028: PetscInt grid;
4029: Vec xcreated = NULL;
4030: DM dm;
4039: {
4040: PetscViewer viewer;
4041: PetscViewerFormat format;
4042: PetscBool flg;
4043: static PetscBool incall = PETSC_FALSE;
4045: if (!incall) {
4046: PetscOptionsGetViewer(PetscObjectComm((PetscObject) snes), ((PetscObject) snes)->prefix, "-snes_convergence_estimate", &viewer, &format, &flg);
4047: if (flg) {
4048: PetscConvEst conv;
4049: PetscReal alpha; /* Convergence rate of the solution error in the L_2 norm */
4051: incall = PETSC_TRUE;
4052: PetscConvEstCreate(PetscObjectComm((PetscObject) snes), &conv);
4053: PetscConvEstSetSolver(conv, snes);
4054: PetscConvEstSetFromOptions(conv);
4055: PetscConvEstSetUp(conv);
4056: PetscConvEstGetConvRate(conv, &alpha);
4057: PetscViewerPushFormat(viewer, format);
4058: PetscConvEstRateView(conv, alpha, viewer);
4059: PetscViewerPopFormat(viewer);
4060: PetscViewerDestroy(&viewer);
4061: PetscConvEstDestroy(&conv);
4062: incall = PETSC_FALSE;
4063: }
4064: }
4065: }
4066: if (!x) {
4067: SNESGetDM(snes,&dm);
4068: DMCreateGlobalVector(dm,&xcreated);
4069: x = xcreated;
4070: }
4071: SNESViewFromOptions(snes,NULL,"-snes_view_pre");
4073: for (grid=0; grid<snes->gridsequence; grid++) {PetscViewerASCIIPushTab(PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)snes)));}
4074: for (grid=0; grid<snes->gridsequence+1; grid++) {
4076: /* set solution vector */
4077: if (!grid) {PetscObjectReference((PetscObject)x);}
4078: VecDestroy(&snes->vec_sol);
4079: snes->vec_sol = x;
4080: SNESGetDM(snes,&dm);
4082: /* set affine vector if provided */
4083: if (b) { PetscObjectReference((PetscObject)b); }
4084: VecDestroy(&snes->vec_rhs);
4085: snes->vec_rhs = b;
4087: if (snes->vec_func == snes->vec_sol) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_IDN,"Solution vector cannot be function vector");
4088: if (snes->vec_rhs == snes->vec_sol) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_IDN,"Solution vector cannot be right hand side vector");
4089: if (!snes->vec_sol_update /* && snes->vec_sol */) {
4090: VecDuplicate(snes->vec_sol,&snes->vec_sol_update);
4091: PetscLogObjectParent((PetscObject)snes,(PetscObject)snes->vec_sol_update);
4092: }
4093: DMShellSetGlobalVector(dm,snes->vec_sol);
4094: SNESSetUp(snes);
4096: if (!grid) {
4097: if (snes->ops->computeinitialguess) {
4098: (*snes->ops->computeinitialguess)(snes,snes->vec_sol,snes->initialguessP);
4099: }
4100: }
4102: if (snes->conv_hist_reset) snes->conv_hist_len = 0;
4103: if (snes->counters_reset) {snes->nfuncs = 0; snes->linear_its = 0; snes->numFailures = 0;}
4105: PetscLogEventBegin(SNES_Solve,snes,0,0,0);
4106: (*snes->ops->solve)(snes);
4107: PetscLogEventEnd(SNES_Solve,snes,0,0,0);
4108: if (!snes->reason) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Internal error, solver returned without setting converged reason");
4109: snes->domainerror = PETSC_FALSE; /* clear the flag if it has been set */
4111: if (snes->lagjac_persist) snes->jac_iter += snes->iter;
4112: if (snes->lagpre_persist) snes->pre_iter += snes->iter;
4114: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->prefix,"-snes_test_local_min",NULL,NULL,&flg);
4115: if (flg && !PetscPreLoadingOn) { SNESTestLocalMin(snes); }
4116: SNESReasonViewFromOptions(snes);
4118: if (snes->errorifnotconverged && snes->reason < 0) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_NOT_CONVERGED,"SNESSolve has not converged");
4119: if (snes->reason < 0) break;
4120: if (grid < snes->gridsequence) {
4121: DM fine;
4122: Vec xnew;
4123: Mat interp;
4125: DMRefine(snes->dm,PetscObjectComm((PetscObject)snes),&fine);
4126: if (!fine) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_INCOMP,"DMRefine() did not perform any refinement, cannot continue grid sequencing");
4127: DMCreateInterpolation(snes->dm,fine,&interp,NULL);
4128: DMCreateGlobalVector(fine,&xnew);
4129: MatInterpolate(interp,x,xnew);
4130: DMInterpolate(snes->dm,interp,fine);
4131: MatDestroy(&interp);
4132: x = xnew;
4134: SNESReset(snes);
4135: SNESSetDM(snes,fine);
4136: DMDestroy(&fine);
4137: PetscViewerASCIIPopTab(PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)snes)));
4138: }
4139: }
4140: SNESViewFromOptions(snes,NULL,"-snes_view");
4141: VecViewFromOptions(snes->vec_sol,(PetscObject)snes,"-snes_view_solution");
4143: VecDestroy(&xcreated);
4144: PetscObjectSAWsBlock((PetscObject)snes);
4145: return(0);
4146: }
4148: /* --------- Internal routines for SNES Package --------- */
4150: /*@C
4151: SNESSetType - Sets the method for the nonlinear solver.
4153: Collective on SNES
4155: Input Parameters:
4156: + snes - the SNES context
4157: - type - a known method
4159: Options Database Key:
4160: . -snes_type <type> - Sets the method; use -help for a list
4161: of available methods (for instance, newtonls or newtontr)
4163: Notes:
4164: See "petsc/include/petscsnes.h" for available methods (for instance)
4165: + SNESNEWTONLS - Newton's method with line search
4166: (systems of nonlinear equations)
4167: . SNESNEWTONTR - Newton's method with trust region
4168: (systems of nonlinear equations)
4170: Normally, it is best to use the SNESSetFromOptions() command and then
4171: set the SNES solver type from the options database rather than by using
4172: this routine. Using the options database provides the user with
4173: maximum flexibility in evaluating the many nonlinear solvers.
4174: The SNESSetType() routine is provided for those situations where it
4175: is necessary to set the nonlinear solver independently of the command
4176: line or options database. This might be the case, for example, when
4177: the choice of solver changes during the execution of the program,
4178: and the user's application is taking responsibility for choosing the
4179: appropriate method.
4181: Developer Notes: SNESRegister() adds a constructor for a new SNESType to SNESList, SNESSetType() locates
4182: the constructor in that list and calls it to create the spexific object.
4184: Level: intermediate
4186: .keywords: SNES, set, type
4188: .seealso: SNESType, SNESCreate(), SNESDestroy(), SNESGetType(), SNESSetFromOptions()
4190: @*/
4191: PetscErrorCode SNESSetType(SNES snes,SNESType type)
4192: {
4193: PetscErrorCode ierr,(*r)(SNES);
4194: PetscBool match;
4200: PetscObjectTypeCompare((PetscObject)snes,type,&match);
4201: if (match) return(0);
4203: PetscFunctionListFind(SNESList,type,&r);
4204: if (!r) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_UNKNOWN_TYPE,"Unable to find requested SNES type %s",type);
4205: /* Destroy the previous private SNES context */
4206: if (snes->ops->destroy) {
4207: (*(snes)->ops->destroy)(snes);
4208: snes->ops->destroy = NULL;
4209: }
4210: /* Reinitialize function pointers in SNESOps structure */
4211: snes->ops->setup = 0;
4212: snes->ops->solve = 0;
4213: snes->ops->view = 0;
4214: snes->ops->setfromoptions = 0;
4215: snes->ops->destroy = 0;
4216: /* Call the SNESCreate_XXX routine for this particular Nonlinear solver */
4217: snes->setupcalled = PETSC_FALSE;
4219: PetscObjectChangeTypeName((PetscObject)snes,type);
4220: (*r)(snes);
4221: return(0);
4222: }
4224: /*@C
4225: SNESGetType - Gets the SNES method type and name (as a string).
4227: Not Collective
4229: Input Parameter:
4230: . snes - nonlinear solver context
4232: Output Parameter:
4233: . type - SNES method (a character string)
4235: Level: intermediate
4237: .keywords: SNES, nonlinear, get, type, name
4238: @*/
4239: PetscErrorCode SNESGetType(SNES snes,SNESType *type)
4240: {
4244: *type = ((PetscObject)snes)->type_name;
4245: return(0);
4246: }
4248: /*@
4249: SNESSetSolution - Sets the solution vector for use by the SNES routines.
4251: Logically Collective on SNES and Vec
4253: Input Parameters:
4254: + snes - the SNES context obtained from SNESCreate()
4255: - u - the solution vector
4257: Level: beginner
4259: .keywords: SNES, set, solution
4260: @*/
4261: PetscErrorCode SNESSetSolution(SNES snes, Vec u)
4262: {
4263: DM dm;
4269: PetscObjectReference((PetscObject) u);
4270: VecDestroy(&snes->vec_sol);
4272: snes->vec_sol = u;
4274: SNESGetDM(snes, &dm);
4275: DMShellSetGlobalVector(dm, u);
4276: return(0);
4277: }
4279: /*@
4280: SNESGetSolution - Returns the vector where the approximate solution is
4281: stored. This is the fine grid solution when using SNESSetGridSequence().
4283: Not Collective, but Vec is parallel if SNES is parallel
4285: Input Parameter:
4286: . snes - the SNES context
4288: Output Parameter:
4289: . x - the solution
4291: Level: intermediate
4293: .keywords: SNES, nonlinear, get, solution
4295: .seealso: SNESGetSolutionUpdate(), SNESGetFunction()
4296: @*/
4297: PetscErrorCode SNESGetSolution(SNES snes,Vec *x)
4298: {
4302: *x = snes->vec_sol;
4303: return(0);
4304: }
4306: /*@
4307: SNESGetSolutionUpdate - Returns the vector where the solution update is
4308: stored.
4310: Not Collective, but Vec is parallel if SNES is parallel
4312: Input Parameter:
4313: . snes - the SNES context
4315: Output Parameter:
4316: . x - the solution update
4318: Level: advanced
4320: .keywords: SNES, nonlinear, get, solution, update
4322: .seealso: SNESGetSolution(), SNESGetFunction()
4323: @*/
4324: PetscErrorCode SNESGetSolutionUpdate(SNES snes,Vec *x)
4325: {
4329: *x = snes->vec_sol_update;
4330: return(0);
4331: }
4333: /*@C
4334: SNESGetFunction - Returns the vector where the function is stored.
4336: Not Collective, but Vec is parallel if SNES is parallel. Collective if Vec is requested, but has not been created yet.
4338: Input Parameter:
4339: . snes - the SNES context
4341: Output Parameter:
4342: + r - the vector that is used to store residuals (or NULL if you don't want it)
4343: . f - the function (or NULL if you don't want it); see SNESFunction for calling sequence details
4344: - ctx - the function context (or NULL if you don't want it)
4346: Level: advanced
4348: .keywords: SNES, nonlinear, get, function
4350: .seealso: SNESSetFunction(), SNESGetSolution(), SNESFunction
4351: @*/
4352: PetscErrorCode SNESGetFunction(SNES snes,Vec *r,PetscErrorCode (**f)(SNES,Vec,Vec,void*),void **ctx)
4353: {
4355: DM dm;
4359: if (r) {
4360: if (!snes->vec_func) {
4361: if (snes->vec_rhs) {
4362: VecDuplicate(snes->vec_rhs,&snes->vec_func);
4363: } else if (snes->vec_sol) {
4364: VecDuplicate(snes->vec_sol,&snes->vec_func);
4365: } else if (snes->dm) {
4366: DMCreateGlobalVector(snes->dm,&snes->vec_func);
4367: }
4368: }
4369: *r = snes->vec_func;
4370: }
4371: SNESGetDM(snes,&dm);
4372: DMSNESGetFunction(dm,f,ctx);
4373: return(0);
4374: }
4376: /*@C
4377: SNESGetNGS - Returns the NGS function and context.
4379: Input Parameter:
4380: . snes - the SNES context
4382: Output Parameter:
4383: + f - the function (or NULL) see SNESNGSFunction for details
4384: - ctx - the function context (or NULL)
4386: Level: advanced
4388: .keywords: SNES, nonlinear, get, function
4390: .seealso: SNESSetNGS(), SNESGetFunction()
4391: @*/
4393: PetscErrorCode SNESGetNGS (SNES snes, PetscErrorCode (**f)(SNES, Vec, Vec, void*), void ** ctx)
4394: {
4396: DM dm;
4400: SNESGetDM(snes,&dm);
4401: DMSNESGetNGS(dm,f,ctx);
4402: return(0);
4403: }
4405: /*@C
4406: SNESSetOptionsPrefix - Sets the prefix used for searching for all
4407: SNES options in the database.
4409: Logically Collective on SNES
4411: Input Parameter:
4412: + snes - the SNES context
4413: - prefix - the prefix to prepend to all option names
4415: Notes:
4416: A hyphen (-) must NOT be given at the beginning of the prefix name.
4417: The first character of all runtime options is AUTOMATICALLY the hyphen.
4419: Level: advanced
4421: .keywords: SNES, set, options, prefix, database
4423: .seealso: SNESSetFromOptions()
4424: @*/
4425: PetscErrorCode SNESSetOptionsPrefix(SNES snes,const char prefix[])
4426: {
4431: PetscObjectSetOptionsPrefix((PetscObject)snes,prefix);
4432: if (!snes->ksp) {SNESGetKSP(snes,&snes->ksp);}
4433: if (snes->linesearch) {
4434: SNESGetLineSearch(snes,&snes->linesearch);
4435: PetscObjectSetOptionsPrefix((PetscObject)snes->linesearch,prefix);
4436: }
4437: KSPSetOptionsPrefix(snes->ksp,prefix);
4438: return(0);
4439: }
4441: /*@C
4442: SNESAppendOptionsPrefix - Appends to the prefix used for searching for all
4443: SNES options in the database.
4445: Logically Collective on SNES
4447: Input Parameters:
4448: + snes - the SNES context
4449: - prefix - the prefix to prepend to all option names
4451: Notes:
4452: A hyphen (-) must NOT be given at the beginning of the prefix name.
4453: The first character of all runtime options is AUTOMATICALLY the hyphen.
4455: Level: advanced
4457: .keywords: SNES, append, options, prefix, database
4459: .seealso: SNESGetOptionsPrefix()
4460: @*/
4461: PetscErrorCode SNESAppendOptionsPrefix(SNES snes,const char prefix[])
4462: {
4467: PetscObjectAppendOptionsPrefix((PetscObject)snes,prefix);
4468: if (!snes->ksp) {SNESGetKSP(snes,&snes->ksp);}
4469: if (snes->linesearch) {
4470: SNESGetLineSearch(snes,&snes->linesearch);
4471: PetscObjectAppendOptionsPrefix((PetscObject)snes->linesearch,prefix);
4472: }
4473: KSPAppendOptionsPrefix(snes->ksp,prefix);
4474: return(0);
4475: }
4477: /*@C
4478: SNESGetOptionsPrefix - Sets the prefix used for searching for all
4479: SNES options in the database.
4481: Not Collective
4483: Input Parameter:
4484: . snes - the SNES context
4486: Output Parameter:
4487: . prefix - pointer to the prefix string used
4489: Notes: On the fortran side, the user should pass in a string 'prefix' of
4490: sufficient length to hold the prefix.
4492: Level: advanced
4494: .keywords: SNES, get, options, prefix, database
4496: .seealso: SNESAppendOptionsPrefix()
4497: @*/
4498: PetscErrorCode SNESGetOptionsPrefix(SNES snes,const char *prefix[])
4499: {
4504: PetscObjectGetOptionsPrefix((PetscObject)snes,prefix);
4505: return(0);
4506: }
4509: /*@C
4510: SNESRegister - Adds a method to the nonlinear solver package.
4512: Not collective
4514: Input Parameters:
4515: + name_solver - name of a new user-defined solver
4516: - routine_create - routine to create method context
4518: Notes:
4519: SNESRegister() may be called multiple times to add several user-defined solvers.
4521: Sample usage:
4522: .vb
4523: SNESRegister("my_solver",MySolverCreate);
4524: .ve
4526: Then, your solver can be chosen with the procedural interface via
4527: $ SNESSetType(snes,"my_solver")
4528: or at runtime via the option
4529: $ -snes_type my_solver
4531: Level: advanced
4533: Note: If your function is not being put into a shared library then use SNESRegister() instead
4535: .keywords: SNES, nonlinear, register
4537: .seealso: SNESRegisterAll(), SNESRegisterDestroy()
4539: Level: advanced
4540: @*/
4541: PetscErrorCode SNESRegister(const char sname[],PetscErrorCode (*function)(SNES))
4542: {
4546: PetscFunctionListAdd(&SNESList,sname,function);
4547: return(0);
4548: }
4550: PetscErrorCode SNESTestLocalMin(SNES snes)
4551: {
4553: PetscInt N,i,j;
4554: Vec u,uh,fh;
4555: PetscScalar value;
4556: PetscReal norm;
4559: SNESGetSolution(snes,&u);
4560: VecDuplicate(u,&uh);
4561: VecDuplicate(u,&fh);
4563: /* currently only works for sequential */
4564: PetscPrintf(PETSC_COMM_WORLD,"Testing FormFunction() for local min\n");
4565: VecGetSize(u,&N);
4566: for (i=0; i<N; i++) {
4567: VecCopy(u,uh);
4568: PetscPrintf(PETSC_COMM_WORLD,"i = %D\n",i);
4569: for (j=-10; j<11; j++) {
4570: value = PetscSign(j)*PetscExpReal(PetscAbs(j)-10.0);
4571: VecSetValue(uh,i,value,ADD_VALUES);
4572: SNESComputeFunction(snes,uh,fh);
4573: VecNorm(fh,NORM_2,&norm);
4574: PetscPrintf(PETSC_COMM_WORLD," j norm %D %18.16e\n",j,norm);
4575: value = -value;
4576: VecSetValue(uh,i,value,ADD_VALUES);
4577: }
4578: }
4579: VecDestroy(&uh);
4580: VecDestroy(&fh);
4581: return(0);
4582: }
4584: /*@
4585: SNESKSPSetUseEW - Sets SNES use Eisenstat-Walker method for
4586: computing relative tolerance for linear solvers within an inexact
4587: Newton method.
4589: Logically Collective on SNES
4591: Input Parameters:
4592: + snes - SNES context
4593: - flag - PETSC_TRUE or PETSC_FALSE
4595: Options Database:
4596: + -snes_ksp_ew - use Eisenstat-Walker method for determining linear system convergence
4597: . -snes_ksp_ew_version ver - version of Eisenstat-Walker method
4598: . -snes_ksp_ew_rtol0 <rtol0> - Sets rtol0
4599: . -snes_ksp_ew_rtolmax <rtolmax> - Sets rtolmax
4600: . -snes_ksp_ew_gamma <gamma> - Sets gamma
4601: . -snes_ksp_ew_alpha <alpha> - Sets alpha
4602: . -snes_ksp_ew_alpha2 <alpha2> - Sets alpha2
4603: - -snes_ksp_ew_threshold <threshold> - Sets threshold
4605: Notes:
4606: Currently, the default is to use a constant relative tolerance for
4607: the inner linear solvers. Alternatively, one can use the
4608: Eisenstat-Walker method, where the relative convergence tolerance
4609: is reset at each Newton iteration according progress of the nonlinear
4610: solver.
4612: Level: advanced
4614: Reference:
4615: S. C. Eisenstat and H. F. Walker, "Choosing the forcing terms in an
4616: inexact Newton method", SISC 17 (1), pp.16-32, 1996.
4618: .keywords: SNES, KSP, Eisenstat, Walker, convergence, test, inexact, Newton
4620: .seealso: SNESKSPGetUseEW(), SNESKSPGetParametersEW(), SNESKSPSetParametersEW()
4621: @*/
4622: PetscErrorCode SNESKSPSetUseEW(SNES snes,PetscBool flag)
4623: {
4627: snes->ksp_ewconv = flag;
4628: return(0);
4629: }
4631: /*@
4632: SNESKSPGetUseEW - Gets if SNES is using Eisenstat-Walker method
4633: for computing relative tolerance for linear solvers within an
4634: inexact Newton method.
4636: Not Collective
4638: Input Parameter:
4639: . snes - SNES context
4641: Output Parameter:
4642: . flag - PETSC_TRUE or PETSC_FALSE
4644: Notes:
4645: Currently, the default is to use a constant relative tolerance for
4646: the inner linear solvers. Alternatively, one can use the
4647: Eisenstat-Walker method, where the relative convergence tolerance
4648: is reset at each Newton iteration according progress of the nonlinear
4649: solver.
4651: Level: advanced
4653: Reference:
4654: S. C. Eisenstat and H. F. Walker, "Choosing the forcing terms in an
4655: inexact Newton method", SISC 17 (1), pp.16-32, 1996.
4657: .keywords: SNES, KSP, Eisenstat, Walker, convergence, test, inexact, Newton
4659: .seealso: SNESKSPSetUseEW(), SNESKSPGetParametersEW(), SNESKSPSetParametersEW()
4660: @*/
4661: PetscErrorCode SNESKSPGetUseEW(SNES snes, PetscBool *flag)
4662: {
4666: *flag = snes->ksp_ewconv;
4667: return(0);
4668: }
4670: /*@
4671: SNESKSPSetParametersEW - Sets parameters for Eisenstat-Walker
4672: convergence criteria for the linear solvers within an inexact
4673: Newton method.
4675: Logically Collective on SNES
4677: Input Parameters:
4678: + snes - SNES context
4679: . version - version 1, 2 (default is 2) or 3
4680: . rtol_0 - initial relative tolerance (0 <= rtol_0 < 1)
4681: . rtol_max - maximum relative tolerance (0 <= rtol_max < 1)
4682: . gamma - multiplicative factor for version 2 rtol computation
4683: (0 <= gamma2 <= 1)
4684: . alpha - power for version 2 rtol computation (1 < alpha <= 2)
4685: . alpha2 - power for safeguard
4686: - threshold - threshold for imposing safeguard (0 < threshold < 1)
4688: Note:
4689: Version 3 was contributed by Luis Chacon, June 2006.
4691: Use PETSC_DEFAULT to retain the default for any of the parameters.
4693: Level: advanced
4695: Reference:
4696: S. C. Eisenstat and H. F. Walker, "Choosing the forcing terms in an
4697: inexact Newton method", Utah State University Math. Stat. Dept. Res.
4698: Report 6/94/75, June, 1994, to appear in SIAM J. Sci. Comput.
4700: .keywords: SNES, KSP, Eisenstat, Walker, set, parameters
4702: .seealso: SNESKSPSetUseEW(), SNESKSPGetUseEW(), SNESKSPGetParametersEW()
4703: @*/
4704: PetscErrorCode SNESKSPSetParametersEW(SNES snes,PetscInt version,PetscReal rtol_0,PetscReal rtol_max,PetscReal gamma,PetscReal alpha,PetscReal alpha2,PetscReal threshold)
4705: {
4706: SNESKSPEW *kctx;
4710: kctx = (SNESKSPEW*)snes->kspconvctx;
4711: if (!kctx) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"No Eisenstat-Walker context existing");
4720: if (version != PETSC_DEFAULT) kctx->version = version;
4721: if (rtol_0 != PETSC_DEFAULT) kctx->rtol_0 = rtol_0;
4722: if (rtol_max != PETSC_DEFAULT) kctx->rtol_max = rtol_max;
4723: if (gamma != PETSC_DEFAULT) kctx->gamma = gamma;
4724: if (alpha != PETSC_DEFAULT) kctx->alpha = alpha;
4725: if (alpha2 != PETSC_DEFAULT) kctx->alpha2 = alpha2;
4726: if (threshold != PETSC_DEFAULT) kctx->threshold = threshold;
4728: 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);
4729: 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);
4730: 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);
4731: 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);
4732: 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);
4733: 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);
4734: return(0);
4735: }
4737: /*@
4738: SNESKSPGetParametersEW - Gets parameters for Eisenstat-Walker
4739: convergence criteria for the linear solvers within an inexact
4740: Newton method.
4742: Not Collective
4744: Input Parameters:
4745: snes - SNES context
4747: Output Parameters:
4748: + version - version 1, 2 (default is 2) or 3
4749: . rtol_0 - initial relative tolerance (0 <= rtol_0 < 1)
4750: . rtol_max - maximum relative tolerance (0 <= rtol_max < 1)
4751: . gamma - multiplicative factor for version 2 rtol computation (0 <= gamma2 <= 1)
4752: . alpha - power for version 2 rtol computation (1 < alpha <= 2)
4753: . alpha2 - power for safeguard
4754: - threshold - threshold for imposing safeguard (0 < threshold < 1)
4756: Level: advanced
4758: .keywords: SNES, KSP, Eisenstat, Walker, get, parameters
4760: .seealso: SNESKSPSetUseEW(), SNESKSPGetUseEW(), SNESKSPSetParametersEW()
4761: @*/
4762: PetscErrorCode SNESKSPGetParametersEW(SNES snes,PetscInt *version,PetscReal *rtol_0,PetscReal *rtol_max,PetscReal *gamma,PetscReal *alpha,PetscReal *alpha2,PetscReal *threshold)
4763: {
4764: SNESKSPEW *kctx;
4768: kctx = (SNESKSPEW*)snes->kspconvctx;
4769: if (!kctx) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"No Eisenstat-Walker context existing");
4770: if (version) *version = kctx->version;
4771: if (rtol_0) *rtol_0 = kctx->rtol_0;
4772: if (rtol_max) *rtol_max = kctx->rtol_max;
4773: if (gamma) *gamma = kctx->gamma;
4774: if (alpha) *alpha = kctx->alpha;
4775: if (alpha2) *alpha2 = kctx->alpha2;
4776: if (threshold) *threshold = kctx->threshold;
4777: return(0);
4778: }
4780: PetscErrorCode KSPPreSolve_SNESEW(KSP ksp, Vec b, Vec x, SNES snes)
4781: {
4783: SNESKSPEW *kctx = (SNESKSPEW*)snes->kspconvctx;
4784: PetscReal rtol = PETSC_DEFAULT,stol;
4787: if (!snes->ksp_ewconv) return(0);
4788: if (!snes->iter) {
4789: rtol = kctx->rtol_0; /* first time in, so use the original user rtol */
4790: VecNorm(snes->vec_func,NORM_2,&kctx->norm_first);
4791: }
4792: else {
4793: if (kctx->version == 1) {
4794: rtol = (snes->norm - kctx->lresid_last)/kctx->norm_last;
4795: if (rtol < 0.0) rtol = -rtol;
4796: stol = PetscPowReal(kctx->rtol_last,kctx->alpha2);
4797: if (stol > kctx->threshold) rtol = PetscMax(rtol,stol);
4798: } else if (kctx->version == 2) {
4799: rtol = kctx->gamma * PetscPowReal(snes->norm/kctx->norm_last,kctx->alpha);
4800: stol = kctx->gamma * PetscPowReal(kctx->rtol_last,kctx->alpha);
4801: if (stol > kctx->threshold) rtol = PetscMax(rtol,stol);
4802: } else if (kctx->version == 3) { /* contributed by Luis Chacon, June 2006. */
4803: rtol = kctx->gamma * PetscPowReal(snes->norm/kctx->norm_last,kctx->alpha);
4804: /* safeguard: avoid sharp decrease of rtol */
4805: stol = kctx->gamma*PetscPowReal(kctx->rtol_last,kctx->alpha);
4806: stol = PetscMax(rtol,stol);
4807: rtol = PetscMin(kctx->rtol_0,stol);
4808: /* safeguard: avoid oversolving */
4809: stol = kctx->gamma*(kctx->norm_first*snes->rtol)/snes->norm;
4810: stol = PetscMax(rtol,stol);
4811: rtol = PetscMin(kctx->rtol_0,stol);
4812: } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Only versions 1, 2 or 3 are supported: %D",kctx->version);
4813: }
4814: /* safeguard: avoid rtol greater than one */
4815: rtol = PetscMin(rtol,kctx->rtol_max);
4816: KSPSetTolerances(ksp,rtol,PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT);
4817: PetscInfo3(snes,"iter %D, Eisenstat-Walker (version %D) KSP rtol=%g\n",snes->iter,kctx->version,(double)rtol);
4818: return(0);
4819: }
4821: PetscErrorCode KSPPostSolve_SNESEW(KSP ksp, Vec b, Vec x, SNES snes)
4822: {
4824: SNESKSPEW *kctx = (SNESKSPEW*)snes->kspconvctx;
4825: PCSide pcside;
4826: Vec lres;
4829: if (!snes->ksp_ewconv) return(0);
4830: KSPGetTolerances(ksp,&kctx->rtol_last,0,0,0);
4831: kctx->norm_last = snes->norm;
4832: if (kctx->version == 1) {
4833: PC pc;
4834: PetscBool isNone;
4836: KSPGetPC(ksp, &pc);
4837: PetscObjectTypeCompare((PetscObject) pc, PCNONE, &isNone);
4838: KSPGetPCSide(ksp,&pcside);
4839: if (pcside == PC_RIGHT || isNone) { /* XXX Should we also test KSP_UNPRECONDITIONED_NORM ? */
4840: /* KSP residual is true linear residual */
4841: KSPGetResidualNorm(ksp,&kctx->lresid_last);
4842: } else {
4843: /* KSP residual is preconditioned residual */
4844: /* compute true linear residual norm */
4845: VecDuplicate(b,&lres);
4846: MatMult(snes->jacobian,x,lres);
4847: VecAYPX(lres,-1.0,b);
4848: VecNorm(lres,NORM_2,&kctx->lresid_last);
4849: VecDestroy(&lres);
4850: }
4851: }
4852: return(0);
4853: }
4855: /*@
4856: SNESGetKSP - Returns the KSP context for a SNES solver.
4858: Not Collective, but if SNES object is parallel, then KSP object is parallel
4860: Input Parameter:
4861: . snes - the SNES context
4863: Output Parameter:
4864: . ksp - the KSP context
4866: Notes:
4867: The user can then directly manipulate the KSP context to set various
4868: options, etc. Likewise, the user can then extract and manipulate the
4869: PC contexts as well.
4871: Level: beginner
4873: .keywords: SNES, nonlinear, get, KSP, context
4875: .seealso: KSPGetPC(), SNESCreate(), KSPCreate(), SNESSetKSP()
4876: @*/
4877: PetscErrorCode SNESGetKSP(SNES snes,KSP *ksp)
4878: {
4885: if (!snes->ksp) {
4886: PetscBool monitor = PETSC_FALSE;
4888: KSPCreate(PetscObjectComm((PetscObject)snes),&snes->ksp);
4889: PetscObjectIncrementTabLevel((PetscObject)snes->ksp,(PetscObject)snes,1);
4890: PetscLogObjectParent((PetscObject)snes,(PetscObject)snes->ksp);
4892: KSPSetPreSolve(snes->ksp,(PetscErrorCode (*)(KSP,Vec,Vec,void*))KSPPreSolve_SNESEW,snes);
4893: KSPSetPostSolve(snes->ksp,(PetscErrorCode (*)(KSP,Vec,Vec,void*))KSPPostSolve_SNESEW,snes);
4895: PetscOptionsGetBool(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-ksp_monitor_snes",&monitor,NULL);
4896: if (monitor) {
4897: KSPMonitorSet(snes->ksp,KSPMonitorSNES,snes,NULL);
4898: }
4899: monitor = PETSC_FALSE;
4900: PetscOptionsGetBool(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-ksp_monitor_snes_lg",&monitor,NULL);
4901: if (monitor) {
4902: PetscObject *objs;
4903: KSPMonitorSNESLGResidualNormCreate(PetscObjectComm((PetscObject)snes),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,600,600,&objs);
4904: objs[0] = (PetscObject) snes;
4905: KSPMonitorSet(snes->ksp,(PetscErrorCode (*)(KSP,PetscInt,PetscReal,void*))KSPMonitorSNESLGResidualNorm,objs,(PetscErrorCode (*)(void**))KSPMonitorSNESLGResidualNormDestroy);
4906: }
4907: }
4908: *ksp = snes->ksp;
4909: return(0);
4910: }
4913: #include <petsc/private/dmimpl.h>
4914: /*@
4915: SNESSetDM - Sets the DM that may be used by some nonlinear solvers or their underlying preconditioners
4917: Logically Collective on SNES
4919: Input Parameters:
4920: + snes - the nonlinear solver context
4921: - dm - the dm, cannot be NULL
4923: Level: intermediate
4925: .seealso: SNESGetDM(), SNESHasDM(), KSPSetDM(), KSPGetDM()
4926: @*/
4927: PetscErrorCode SNESSetDM(SNES snes,DM dm)
4928: {
4930: KSP ksp;
4931: DMSNES sdm;
4936: PetscObjectReference((PetscObject)dm);
4937: if (snes->dm) { /* Move the DMSNES context over to the new DM unless the new DM already has one */
4938: if (snes->dm->dmsnes && !dm->dmsnes) {
4939: DMCopyDMSNES(snes->dm,dm);
4940: DMGetDMSNES(snes->dm,&sdm);
4941: if (sdm->originaldm == snes->dm) sdm->originaldm = dm; /* Grant write privileges to the replacement DM */
4942: }
4943: DMDestroy(&snes->dm);
4944: }
4945: snes->dm = dm;
4946: snes->dmAuto = PETSC_FALSE;
4948: SNESGetKSP(snes,&ksp);
4949: KSPSetDM(ksp,dm);
4950: KSPSetDMActive(ksp,PETSC_FALSE);
4951: if (snes->npc) {
4952: SNESSetDM(snes->npc, snes->dm);
4953: SNESSetNPCSide(snes,snes->npcside);
4954: }
4955: return(0);
4956: }
4958: /*@
4959: SNESGetDM - Gets the DM that may be used by some preconditioners
4961: Not Collective but DM obtained is parallel on SNES
4963: Input Parameter:
4964: . snes - the preconditioner context
4966: Output Parameter:
4967: . dm - the dm
4969: Level: intermediate
4971: .seealso: SNESSetDM(), SNESHasDM(), KSPSetDM(), KSPGetDM()
4972: @*/
4973: PetscErrorCode SNESGetDM(SNES snes,DM *dm)
4974: {
4979: if (!snes->dm) {
4980: DMShellCreate(PetscObjectComm((PetscObject)snes),&snes->dm);
4981: snes->dmAuto = PETSC_TRUE;
4982: }
4983: *dm = snes->dm;
4984: return(0);
4985: }
4988: /*@
4989: SNESHasDM - Whether snes has dm
4991: Not collective but all processes must return the same value
4993: Input Parameter:
4994: . snes - the nonlinear solver object
4996: Output Parameter:
4997: . hasdm - a flag indicates whether there is dm in snes
4999: Level: intermediate
5001: .seealso: SNESGetDM(), SNESSetDM(), KSPSetDM(), KSPGetDM()
5002: @*/
5003: PetscErrorCode SNESHasDM(SNES snes,PetscBool *hasdm)
5004: {
5008: if (snes->dm) *hasdm = PETSC_TRUE;
5009: else *hasdm = PETSC_FALSE;
5010: return(0);
5011: }
5013: /*@
5014: SNESSetNPC - Sets the nonlinear preconditioner to be used.
5016: Collective on SNES
5018: Input Parameters:
5019: + snes - iterative context obtained from SNESCreate()
5020: - pc - the preconditioner object
5022: Notes:
5023: Use SNESGetNPC() to retrieve the preconditioner context (for example,
5024: to configure it using the API).
5026: Level: developer
5028: .keywords: SNES, set, precondition
5029: .seealso: SNESGetNPC(), SNESHasNPC()
5030: @*/
5031: PetscErrorCode SNESSetNPC(SNES snes, SNES pc)
5032: {
5039: PetscObjectReference((PetscObject) pc);
5040: SNESDestroy(&snes->npc);
5041: snes->npc = pc;
5042: PetscLogObjectParent((PetscObject)snes, (PetscObject)snes->npc);
5043: return(0);
5044: }
5046: /*@
5047: SNESGetNPC - Creates a nonlinear preconditioning solver (SNES) to be used to precondition the nonlinear solver.
5049: Not Collective
5051: Input Parameter:
5052: . snes - iterative context obtained from SNESCreate()
5054: Output Parameter:
5055: . pc - preconditioner context
5057: Notes: If a SNES was previously set with SNESSetNPC() then that SNES is returned.
5059: Level: developer
5061: .keywords: SNES, get, preconditioner
5062: .seealso: SNESSetNPC(), SNESHasNPC()
5063: @*/
5064: PetscErrorCode SNESGetNPC(SNES snes, SNES *pc)
5065: {
5067: const char *optionsprefix;
5072: if (!snes->npc) {
5073: SNESCreate(PetscObjectComm((PetscObject)snes),&snes->npc);
5074: PetscObjectIncrementTabLevel((PetscObject)snes->npc,(PetscObject)snes,1);
5075: PetscLogObjectParent((PetscObject)snes,(PetscObject)snes->npc);
5076: SNESGetOptionsPrefix(snes,&optionsprefix);
5077: SNESSetOptionsPrefix(snes->npc,optionsprefix);
5078: SNESAppendOptionsPrefix(snes->npc,"npc_");
5079: SNESSetCountersReset(snes->npc,PETSC_FALSE);
5080: }
5081: *pc = snes->npc;
5082: return(0);
5083: }
5085: /*@
5086: SNESHasNPC - Returns whether a nonlinear preconditioner exists
5088: Not Collective
5090: Input Parameter:
5091: . snes - iterative context obtained from SNESCreate()
5093: Output Parameter:
5094: . has_npc - whether the SNES has an NPC or not
5096: Level: developer
5098: .keywords: SNES, has, preconditioner
5099: .seealso: SNESSetNPC(), SNESGetNPC()
5100: @*/
5101: PetscErrorCode SNESHasNPC(SNES snes, PetscBool *has_npc)
5102: {
5105: *has_npc = (PetscBool) (snes->npc ? PETSC_TRUE : PETSC_FALSE);
5106: return(0);
5107: }
5109: /*@
5110: SNESSetNPCSide - Sets the preconditioning side.
5112: Logically Collective on SNES
5114: Input Parameter:
5115: . snes - iterative context obtained from SNESCreate()
5117: Output Parameter:
5118: . side - the preconditioning side, where side is one of
5119: .vb
5120: PC_LEFT - left preconditioning
5121: PC_RIGHT - right preconditioning (default for most nonlinear solvers)
5122: .ve
5124: Options Database Keys:
5125: . -snes_pc_side <right,left>
5127: Notes: SNESNRICHARDSON and SNESNCG only support left preconditioning.
5129: Level: intermediate
5131: .keywords: SNES, set, right, left, side, preconditioner, flag
5133: .seealso: SNESGetNPCSide(), KSPSetPCSide()
5134: @*/
5135: PetscErrorCode SNESSetNPCSide(SNES snes,PCSide side)
5136: {
5140: snes->npcside= side;
5141: return(0);
5142: }
5144: /*@
5145: SNESGetNPCSide - Gets the preconditioning side.
5147: Not Collective
5149: Input Parameter:
5150: . snes - iterative context obtained from SNESCreate()
5152: Output Parameter:
5153: . side - the preconditioning side, where side is one of
5154: .vb
5155: PC_LEFT - left preconditioning
5156: PC_RIGHT - right preconditioning (default for most nonlinear solvers)
5157: .ve
5159: Level: intermediate
5161: .keywords: SNES, get, right, left, side, preconditioner, flag
5163: .seealso: SNESSetNPCSide(), KSPGetPCSide()
5164: @*/
5165: PetscErrorCode SNESGetNPCSide(SNES snes,PCSide *side)
5166: {
5170: *side = snes->npcside;
5171: return(0);
5172: }
5174: /*@
5175: SNESSetLineSearch - Sets the linesearch on the SNES instance.
5177: Collective on SNES
5179: Input Parameters:
5180: + snes - iterative context obtained from SNESCreate()
5181: - linesearch - the linesearch object
5183: Notes:
5184: Use SNESGetLineSearch() to retrieve the preconditioner context (for example,
5185: to configure it using the API).
5187: Level: developer
5189: .keywords: SNES, set, linesearch
5190: .seealso: SNESGetLineSearch()
5191: @*/
5192: PetscErrorCode SNESSetLineSearch(SNES snes, SNESLineSearch linesearch)
5193: {
5200: PetscObjectReference((PetscObject) linesearch);
5201: SNESLineSearchDestroy(&snes->linesearch);
5203: snes->linesearch = linesearch;
5205: PetscLogObjectParent((PetscObject)snes, (PetscObject)snes->linesearch);
5206: return(0);
5207: }
5209: /*@
5210: SNESGetLineSearch - Returns a pointer to the line search context set with SNESSetLineSearch()
5211: or creates a default line search instance associated with the SNES and returns it.
5213: Not Collective
5215: Input Parameter:
5216: . snes - iterative context obtained from SNESCreate()
5218: Output Parameter:
5219: . linesearch - linesearch context
5221: Level: beginner
5223: .keywords: SNES, get, linesearch
5224: .seealso: SNESSetLineSearch(), SNESLineSearchCreate()
5225: @*/
5226: PetscErrorCode SNESGetLineSearch(SNES snes, SNESLineSearch *linesearch)
5227: {
5229: const char *optionsprefix;
5234: if (!snes->linesearch) {
5235: SNESGetOptionsPrefix(snes, &optionsprefix);
5236: SNESLineSearchCreate(PetscObjectComm((PetscObject)snes), &snes->linesearch);
5237: SNESLineSearchSetSNES(snes->linesearch, snes);
5238: SNESLineSearchAppendOptionsPrefix(snes->linesearch, optionsprefix);
5239: PetscObjectIncrementTabLevel((PetscObject) snes->linesearch, (PetscObject) snes, 1);
5240: PetscLogObjectParent((PetscObject)snes, (PetscObject)snes->linesearch);
5241: }
5242: *linesearch = snes->linesearch;
5243: return(0);
5244: }
5246: #if defined(PETSC_HAVE_MATLAB_ENGINE)
5247: #include <mex.h>
5249: typedef struct {char *funcname; mxArray *ctx;} SNESMatlabContext;
5251: /*
5252: SNESComputeFunction_Matlab - Calls the function that has been set with SNESSetFunctionMatlab().
5254: Collective on SNES
5256: Input Parameters:
5257: + snes - the SNES context
5258: - x - input vector
5260: Output Parameter:
5261: . y - function vector, as set by SNESSetFunction()
5263: Notes:
5264: SNESComputeFunction() is typically used within nonlinear solvers
5265: implementations, so most users would not generally call this routine
5266: themselves.
5268: Level: developer
5270: .keywords: SNES, nonlinear, compute, function
5272: .seealso: SNESSetFunction(), SNESGetFunction()
5273: */
5274: PetscErrorCode SNESComputeFunction_Matlab(SNES snes,Vec x,Vec y, void *ctx)
5275: {
5276: PetscErrorCode ierr;
5277: SNESMatlabContext *sctx = (SNESMatlabContext*)ctx;
5278: int nlhs = 1,nrhs = 5;
5279: mxArray *plhs[1],*prhs[5];
5280: long long int lx = 0,ly = 0,ls = 0;
5289: /* call Matlab function in ctx with arguments x and y */
5291: PetscMemcpy(&ls,&snes,sizeof(snes));
5292: PetscMemcpy(&lx,&x,sizeof(x));
5293: PetscMemcpy(&ly,&y,sizeof(x));
5294: prhs[0] = mxCreateDoubleScalar((double)ls);
5295: prhs[1] = mxCreateDoubleScalar((double)lx);
5296: prhs[2] = mxCreateDoubleScalar((double)ly);
5297: prhs[3] = mxCreateString(sctx->funcname);
5298: prhs[4] = sctx->ctx;
5299: mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscSNESComputeFunctionInternal");
5300: mxGetScalar(plhs[0]);
5301: mxDestroyArray(prhs[0]);
5302: mxDestroyArray(prhs[1]);
5303: mxDestroyArray(prhs[2]);
5304: mxDestroyArray(prhs[3]);
5305: mxDestroyArray(plhs[0]);
5306: return(0);
5307: }
5309: /*
5310: SNESSetFunctionMatlab - Sets the function evaluation routine and function
5311: vector for use by the SNES routines in solving systems of nonlinear
5312: equations from MATLAB. Here the function is a string containing the name of a MATLAB function
5314: Logically Collective on SNES
5316: Input Parameters:
5317: + snes - the SNES context
5318: . r - vector to store function value
5319: - f - function evaluation routine
5321: Notes:
5322: The Newton-like methods typically solve linear systems of the form
5323: $ f'(x) x = -f(x),
5324: where f'(x) denotes the Jacobian matrix and f(x) is the function.
5326: Level: beginner
5328: Developer Note: This bleeds the allocated memory SNESMatlabContext *sctx;
5330: .keywords: SNES, nonlinear, set, function
5332: .seealso: SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESSetFunction()
5333: */
5334: PetscErrorCode SNESSetFunctionMatlab(SNES snes,Vec r,const char *f,mxArray *ctx)
5335: {
5336: PetscErrorCode ierr;
5337: SNESMatlabContext *sctx;
5340: /* currently sctx is memory bleed */
5341: PetscNew(&sctx);
5342: PetscStrallocpy(f,&sctx->funcname);
5343: /*
5344: This should work, but it doesn't
5345: sctx->ctx = ctx;
5346: mexMakeArrayPersistent(sctx->ctx);
5347: */
5348: sctx->ctx = mxDuplicateArray(ctx);
5349: SNESSetFunction(snes,r,SNESComputeFunction_Matlab,sctx);
5350: return(0);
5351: }
5353: /*
5354: SNESComputeJacobian_Matlab - Calls the function that has been set with SNESSetJacobianMatlab().
5356: Collective on SNES
5358: Input Parameters:
5359: + snes - the SNES context
5360: . x - input vector
5361: . A, B - the matrices
5362: - ctx - user context
5364: Level: developer
5366: .keywords: SNES, nonlinear, compute, function
5368: .seealso: SNESSetFunction(), SNESGetFunction()
5369: @*/
5370: PetscErrorCode SNESComputeJacobian_Matlab(SNES snes,Vec x,Mat A,Mat B,void *ctx)
5371: {
5372: PetscErrorCode ierr;
5373: SNESMatlabContext *sctx = (SNESMatlabContext*)ctx;
5374: int nlhs = 2,nrhs = 6;
5375: mxArray *plhs[2],*prhs[6];
5376: long long int lx = 0,lA = 0,ls = 0, lB = 0;
5382: /* call Matlab function in ctx with arguments x and y */
5384: PetscMemcpy(&ls,&snes,sizeof(snes));
5385: PetscMemcpy(&lx,&x,sizeof(x));
5386: PetscMemcpy(&lA,A,sizeof(x));
5387: PetscMemcpy(&lB,B,sizeof(x));
5388: prhs[0] = mxCreateDoubleScalar((double)ls);
5389: prhs[1] = mxCreateDoubleScalar((double)lx);
5390: prhs[2] = mxCreateDoubleScalar((double)lA);
5391: prhs[3] = mxCreateDoubleScalar((double)lB);
5392: prhs[4] = mxCreateString(sctx->funcname);
5393: prhs[5] = sctx->ctx;
5394: mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscSNESComputeJacobianInternal");
5395: mxGetScalar(plhs[0]);
5396: mxDestroyArray(prhs[0]);
5397: mxDestroyArray(prhs[1]);
5398: mxDestroyArray(prhs[2]);
5399: mxDestroyArray(prhs[3]);
5400: mxDestroyArray(prhs[4]);
5401: mxDestroyArray(plhs[0]);
5402: mxDestroyArray(plhs[1]);
5403: return(0);
5404: }
5406: /*
5407: SNESSetJacobianMatlab - Sets the Jacobian function evaluation routine and two empty Jacobian matrices
5408: vector for use by the SNES routines in solving systems of nonlinear
5409: equations from MATLAB. Here the function is a string containing the name of a MATLAB function
5411: Logically Collective on SNES
5413: Input Parameters:
5414: + snes - the SNES context
5415: . A,B - Jacobian matrices
5416: . J - function evaluation routine
5417: - ctx - user context
5419: Level: developer
5421: Developer Note: This bleeds the allocated memory SNESMatlabContext *sctx;
5423: .keywords: SNES, nonlinear, set, function
5425: .seealso: SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESSetFunction(), J
5426: */
5427: PetscErrorCode SNESSetJacobianMatlab(SNES snes,Mat A,Mat B,const char *J,mxArray *ctx)
5428: {
5429: PetscErrorCode ierr;
5430: SNESMatlabContext *sctx;
5433: /* currently sctx is memory bleed */
5434: PetscNew(&sctx);
5435: PetscStrallocpy(J,&sctx->funcname);
5436: /*
5437: This should work, but it doesn't
5438: sctx->ctx = ctx;
5439: mexMakeArrayPersistent(sctx->ctx);
5440: */
5441: sctx->ctx = mxDuplicateArray(ctx);
5442: SNESSetJacobian(snes,A,B,SNESComputeJacobian_Matlab,sctx);
5443: return(0);
5444: }
5446: /*
5447: SNESMonitor_Matlab - Calls the function that has been set with SNESMonitorSetMatlab().
5449: Collective on SNES
5451: .seealso: SNESSetFunction(), SNESGetFunction()
5452: @*/
5453: PetscErrorCode SNESMonitor_Matlab(SNES snes,PetscInt it, PetscReal fnorm, void *ctx)
5454: {
5455: PetscErrorCode ierr;
5456: SNESMatlabContext *sctx = (SNESMatlabContext*)ctx;
5457: int nlhs = 1,nrhs = 6;
5458: mxArray *plhs[1],*prhs[6];
5459: long long int lx = 0,ls = 0;
5460: Vec x = snes->vec_sol;
5465: PetscMemcpy(&ls,&snes,sizeof(snes));
5466: PetscMemcpy(&lx,&x,sizeof(x));
5467: prhs[0] = mxCreateDoubleScalar((double)ls);
5468: prhs[1] = mxCreateDoubleScalar((double)it);
5469: prhs[2] = mxCreateDoubleScalar((double)fnorm);
5470: prhs[3] = mxCreateDoubleScalar((double)lx);
5471: prhs[4] = mxCreateString(sctx->funcname);
5472: prhs[5] = sctx->ctx;
5473: mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscSNESMonitorInternal");
5474: mxGetScalar(plhs[0]);
5475: mxDestroyArray(prhs[0]);
5476: mxDestroyArray(prhs[1]);
5477: mxDestroyArray(prhs[2]);
5478: mxDestroyArray(prhs[3]);
5479: mxDestroyArray(prhs[4]);
5480: mxDestroyArray(plhs[0]);
5481: return(0);
5482: }
5484: /*
5485: SNESMonitorSetMatlab - Sets the monitor function from MATLAB
5487: Level: developer
5489: Developer Note: This bleeds the allocated memory SNESMatlabContext *sctx;
5491: .keywords: SNES, nonlinear, set, function
5493: .seealso: SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESSetFunction()
5494: */
5495: PetscErrorCode SNESMonitorSetMatlab(SNES snes,const char *f,mxArray *ctx)
5496: {
5497: PetscErrorCode ierr;
5498: SNESMatlabContext *sctx;
5501: /* currently sctx is memory bleed */
5502: PetscNew(&sctx);
5503: PetscStrallocpy(f,&sctx->funcname);
5504: /*
5505: This should work, but it doesn't
5506: sctx->ctx = ctx;
5507: mexMakeArrayPersistent(sctx->ctx);
5508: */
5509: sctx->ctx = mxDuplicateArray(ctx);
5510: SNESMonitorSet(snes,SNESMonitor_Matlab,sctx,NULL);
5511: return(0);
5512: }
5514: #endif