Actual source code: snes.c
petsc-master 2020-09-18
1: #include <petsc/private/snesimpl.h>
2: #include <petscdmshell.h>
3: #include <petscdraw.h>
4: #include <petscds.h>
5: #include <petscdmadaptor.h>
6: #include <petscconvest.h>
8: PetscBool SNESRegisterAllCalled = PETSC_FALSE;
9: PetscFunctionList SNESList = NULL;
11: /* Logging support */
12: PetscClassId SNES_CLASSID, DMSNES_CLASSID;
13: PetscLogEvent SNES_Solve, SNES_Setup, 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: .seealso: SNESGetErrorIfNotConverged(), KSPGetErrorIfNotConverged(), KSPSetErrorIFNotConverged()
34: @*/
35: PetscErrorCode SNESSetErrorIfNotConverged(SNES snes,PetscBool flg)
36: {
40: snes->errorifnotconverged = flg;
41: return(0);
42: }
44: /*@
45: SNESGetErrorIfNotConverged - Will SNESSolve() generate an error if the solver does not converge?
47: Not Collective
49: Input Parameter:
50: . snes - iterative context obtained from SNESCreate()
52: Output Parameter:
53: . flag - PETSC_TRUE if it will generate an error, else PETSC_FALSE
55: Level: intermediate
57: .seealso: SNESSetErrorIfNotConverged(), KSPGetErrorIfNotConverged(), KSPSetErrorIFNotConverged()
58: @*/
59: PetscErrorCode SNESGetErrorIfNotConverged(SNES snes,PetscBool *flag)
60: {
64: *flag = snes->errorifnotconverged;
65: return(0);
66: }
68: /*@
69: SNESSetAlwaysComputesFinalResidual - does the SNES always compute the residual at the final solution?
71: Logically Collective on SNES
73: Input Parameters:
74: + snes - the shell SNES
75: - flg - is the residual computed?
77: Level: advanced
79: .seealso: SNESGetAlwaysComputesFinalResidual()
80: @*/
81: PetscErrorCode SNESSetAlwaysComputesFinalResidual(SNES snes, PetscBool flg)
82: {
85: snes->alwayscomputesfinalresidual = flg;
86: return(0);
87: }
89: /*@
90: SNESGetAlwaysComputesFinalResidual - does the SNES always compute the residual at the final solution?
92: Logically Collective on SNES
94: Input Parameter:
95: . snes - the shell SNES
97: Output Parameter:
98: . flg - is the residual computed?
100: Level: advanced
102: .seealso: SNESSetAlwaysComputesFinalResidual()
103: @*/
104: PetscErrorCode SNESGetAlwaysComputesFinalResidual(SNES snes, PetscBool *flg)
105: {
108: *flg = snes->alwayscomputesfinalresidual;
109: return(0);
110: }
112: /*@
113: SNESSetFunctionDomainError - tells SNES that the input vector to your SNESFunction is not
114: in the functions domain. For example, negative pressure.
116: Logically Collective on SNES
118: Input Parameters:
119: . snes - the SNES context
121: Level: advanced
123: .seealso: SNESCreate(), SNESSetFunction(), SNESFunction
124: @*/
125: PetscErrorCode SNESSetFunctionDomainError(SNES snes)
126: {
129: if (snes->errorifnotconverged) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"User code indicates input vector is not in the function domain");
130: snes->domainerror = PETSC_TRUE;
131: return(0);
132: }
134: /*@
135: SNESSetJacobianDomainError - tells SNES that computeJacobian does not make sense any more. For example there is a negative element transformation.
137: Logically Collective on SNES
139: Input Parameters:
140: . snes - the SNES context
142: Level: advanced
144: .seealso: SNESCreate(), SNESSetFunction(), SNESFunction(), SNESSetFunctionDomainError()
145: @*/
146: PetscErrorCode SNESSetJacobianDomainError(SNES snes)
147: {
150: if (snes->errorifnotconverged) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"User code indicates computeJacobian does not make sense");
151: snes->jacobiandomainerror = PETSC_TRUE;
152: return(0);
153: }
155: /*@
156: SNESSetCheckJacobianDomainError - if or not to check jacobian domain error after each Jacobian evaluation. By default, we check Jacobian domain error
157: in the debug mode, and do not check it in the optimized mode.
159: Logically Collective on SNES
161: Input Parameters:
162: + snes - the SNES context
163: - flg - indicates if or not to check jacobian domain error after each Jacobian evaluation
165: Level: advanced
167: .seealso: SNESCreate(), SNESSetFunction(), SNESFunction(), SNESSetFunctionDomainError(), SNESGetCheckJacobianDomainError()
168: @*/
169: PetscErrorCode SNESSetCheckJacobianDomainError(SNES snes, PetscBool flg)
170: {
173: snes->checkjacdomainerror = flg;
174: return(0);
175: }
177: /*@
178: SNESGetCheckJacobianDomainError - Get an indicator whether or not we are checking Jacobian domain errors after each Jacobian evaluation.
180: Logically Collective on SNES
182: Input Parameters:
183: . snes - the SNES context
185: Output Parameters:
186: . flg - PETSC_FALSE indicates that we don't check jacobian domain errors after each Jacobian evaluation
188: Level: advanced
190: .seealso: SNESCreate(), SNESSetFunction(), SNESFunction(), SNESSetFunctionDomainError(), SNESSetCheckJacobianDomainError()
191: @*/
192: PetscErrorCode SNESGetCheckJacobianDomainError(SNES snes, PetscBool *flg)
193: {
197: *flg = snes->checkjacdomainerror;
198: return(0);
199: }
201: /*@
202: SNESGetFunctionDomainError - Gets the status of the domain error after a call to SNESComputeFunction;
204: Logically Collective on SNES
206: Input Parameters:
207: . snes - the SNES context
209: Output Parameters:
210: . domainerror - Set to PETSC_TRUE if there's a domain error; PETSC_FALSE otherwise.
212: Level: advanced
214: .seealso: SNESSetFunctionDomainError(), SNESComputeFunction()
215: @*/
216: PetscErrorCode SNESGetFunctionDomainError(SNES snes, PetscBool *domainerror)
217: {
221: *domainerror = snes->domainerror;
222: return(0);
223: }
225: /*@
226: SNESGetJacobianDomainError - Gets the status of the Jacobian domain error after a call to SNESComputeJacobian;
228: Logically Collective on SNES
230: Input Parameters:
231: . snes - the SNES context
233: Output Parameters:
234: . domainerror - Set to PETSC_TRUE if there's a jacobian domain error; PETSC_FALSE otherwise.
236: Level: advanced
238: .seealso: SNESSetFunctionDomainError(), SNESComputeFunction(),SNESGetFunctionDomainError()
239: @*/
240: PetscErrorCode SNESGetJacobianDomainError(SNES snes, PetscBool *domainerror)
241: {
245: *domainerror = snes->jacobiandomainerror;
246: return(0);
247: }
249: /*@C
250: SNESLoad - Loads a SNES that has been stored in binary with SNESView().
252: Collective on PetscViewer
254: Input Parameters:
255: + newdm - the newly loaded SNES, this needs to have been created with SNESCreate() or
256: some related function before a call to SNESLoad().
257: - viewer - binary file viewer, obtained from PetscViewerBinaryOpen()
259: Level: intermediate
261: Notes:
262: The type is determined by the data in the file, any type set into the SNES before this call is ignored.
264: Notes for advanced users:
265: Most users should not need to know the details of the binary storage
266: format, since SNESLoad() and TSView() completely hide these details.
267: But for anyone who's interested, the standard binary matrix storage
268: format is
269: .vb
270: has not yet been determined
271: .ve
273: .seealso: PetscViewerBinaryOpen(), SNESView(), MatLoad(), VecLoad()
274: @*/
275: PetscErrorCode SNESLoad(SNES snes, PetscViewer viewer)
276: {
278: PetscBool isbinary;
279: PetscInt classid;
280: char type[256];
281: KSP ksp;
282: DM dm;
283: DMSNES dmsnes;
288: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);
289: if (!isbinary) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Invalid viewer; open viewer with PetscViewerBinaryOpen()");
291: PetscViewerBinaryRead(viewer,&classid,1,NULL,PETSC_INT);
292: if (classid != SNES_FILE_CLASSID) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONG,"Not SNES next in file");
293: PetscViewerBinaryRead(viewer,type,256,NULL,PETSC_CHAR);
294: SNESSetType(snes, type);
295: if (snes->ops->load) {
296: (*snes->ops->load)(snes,viewer);
297: }
298: SNESGetDM(snes,&dm);
299: DMGetDMSNES(dm,&dmsnes);
300: DMSNESLoad(dmsnes,viewer);
301: SNESGetKSP(snes,&ksp);
302: KSPLoad(ksp,viewer);
303: return(0);
304: }
306: #include <petscdraw.h>
307: #if defined(PETSC_HAVE_SAWS)
308: #include <petscviewersaws.h>
309: #endif
311: /*@C
312: SNESViewFromOptions - View from Options
314: Collective on SNES
316: Input Parameters:
317: + A - the application ordering context
318: . obj - Optional object
319: - name - command line option
321: Level: intermediate
322: .seealso: SNES, SNESView, PetscObjectViewFromOptions(), SNESCreate()
323: @*/
324: PetscErrorCode SNESViewFromOptions(SNES A,PetscObject obj,const char name[])
325: {
330: PetscObjectViewFromOptions((PetscObject)A,obj,name);
331: return(0);
332: }
334: PETSC_EXTERN PetscErrorCode SNESComputeJacobian_DMDA(SNES,Vec,Mat,Mat,void*);
336: /*@C
337: SNESView - Prints the SNES data structure.
339: Collective on SNES
341: Input Parameters:
342: + SNES - the SNES context
343: - viewer - visualization context
345: Options Database Key:
346: . -snes_view - Calls SNESView() at end of SNESSolve()
348: Notes:
349: The available visualization contexts include
350: + PETSC_VIEWER_STDOUT_SELF - standard output (default)
351: - PETSC_VIEWER_STDOUT_WORLD - synchronized standard
352: output where only the first processor opens
353: the file. All other processors send their
354: data to the first processor to print.
356: The user can open an alternative visualization context with
357: PetscViewerASCIIOpen() - output to a specified file.
359: Level: beginner
361: .seealso: PetscViewerASCIIOpen()
362: @*/
363: PetscErrorCode SNESView(SNES snes,PetscViewer viewer)
364: {
365: SNESKSPEW *kctx;
367: KSP ksp;
368: SNESLineSearch linesearch;
369: PetscBool iascii,isstring,isbinary,isdraw;
370: DMSNES dmsnes;
371: #if defined(PETSC_HAVE_SAWS)
372: PetscBool issaws;
373: #endif
377: if (!viewer) {
378: PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)snes),&viewer);
379: }
383: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);
384: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSTRING,&isstring);
385: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);
386: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);
387: #if defined(PETSC_HAVE_SAWS)
388: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSAWS,&issaws);
389: #endif
390: if (iascii) {
391: SNESNormSchedule normschedule;
392: DM dm;
393: PetscErrorCode (*cJ)(SNES,Vec,Mat,Mat,void*);
394: void *ctx;
395: const char *pre = "";
397: PetscObjectPrintClassNamePrefixType((PetscObject)snes,viewer);
398: if (!snes->setupcalled) {
399: PetscViewerASCIIPrintf(viewer," SNES has not been set up so information may be incomplete\n");
400: }
401: if (snes->ops->view) {
402: PetscViewerASCIIPushTab(viewer);
403: (*snes->ops->view)(snes,viewer);
404: PetscViewerASCIIPopTab(viewer);
405: }
406: PetscViewerASCIIPrintf(viewer," maximum iterations=%D, maximum function evaluations=%D\n",snes->max_its,snes->max_funcs);
407: PetscViewerASCIIPrintf(viewer," tolerances: relative=%g, absolute=%g, solution=%g\n",(double)snes->rtol,(double)snes->abstol,(double)snes->stol);
408: if (snes->usesksp) {
409: PetscViewerASCIIPrintf(viewer," total number of linear solver iterations=%D\n",snes->linear_its);
410: }
411: PetscViewerASCIIPrintf(viewer," total number of function evaluations=%D\n",snes->nfuncs);
412: SNESGetNormSchedule(snes, &normschedule);
413: if (normschedule > 0) {PetscViewerASCIIPrintf(viewer," norm schedule %s\n",SNESNormSchedules[normschedule]);}
414: if (snes->gridsequence) {
415: PetscViewerASCIIPrintf(viewer," total number of grid sequence refinements=%D\n",snes->gridsequence);
416: }
417: if (snes->ksp_ewconv) {
418: kctx = (SNESKSPEW*)snes->kspconvctx;
419: if (kctx) {
420: PetscViewerASCIIPrintf(viewer," Eisenstat-Walker computation of KSP relative tolerance (version %D)\n",kctx->version);
421: PetscViewerASCIIPrintf(viewer," rtol_0=%g, rtol_max=%g, threshold=%g\n",(double)kctx->rtol_0,(double)kctx->rtol_max,(double)kctx->threshold);
422: PetscViewerASCIIPrintf(viewer," gamma=%g, alpha=%g, alpha2=%g\n",(double)kctx->gamma,(double)kctx->alpha,(double)kctx->alpha2);
423: }
424: }
425: if (snes->lagpreconditioner == -1) {
426: PetscViewerASCIIPrintf(viewer," Preconditioned is never rebuilt\n");
427: } else if (snes->lagpreconditioner > 1) {
428: PetscViewerASCIIPrintf(viewer," Preconditioned is rebuilt every %D new Jacobians\n",snes->lagpreconditioner);
429: }
430: if (snes->lagjacobian == -1) {
431: PetscViewerASCIIPrintf(viewer," Jacobian is never rebuilt\n");
432: } else if (snes->lagjacobian > 1) {
433: PetscViewerASCIIPrintf(viewer," Jacobian is rebuilt every %D SNES iterations\n",snes->lagjacobian);
434: }
435: SNESGetDM(snes,&dm);
436: DMSNESGetJacobian(dm,&cJ,&ctx);
437: if (snes->mf_operator) {
438: PetscViewerASCIIPrintf(viewer," Jacobian is applied matrix-free with differencing\n");
439: pre = "Preconditioning ";
440: }
441: if (cJ == SNESComputeJacobianDefault) {
442: PetscViewerASCIIPrintf(viewer," %sJacobian is built using finite differences one column at a time\n",pre);
443: } else if (cJ == SNESComputeJacobianDefaultColor) {
444: PetscViewerASCIIPrintf(viewer," %sJacobian is built using finite differences with coloring\n",pre);
445: /* it slightly breaks data encapsulation for access the DMDA information directly */
446: } else if (cJ == SNESComputeJacobian_DMDA) {
447: MatFDColoring fdcoloring;
448: PetscObjectQuery((PetscObject)dm,"DMDASNES_FDCOLORING",(PetscObject*)&fdcoloring);
449: if (fdcoloring) {
450: PetscViewerASCIIPrintf(viewer," %sJacobian is built using colored finite differences on a DMDA\n",pre);
451: } else {
452: PetscViewerASCIIPrintf(viewer," %sJacobian is built using a DMDA local Jacobian\n",pre);
453: }
454: } else if (snes->mf) {
455: PetscViewerASCIIPrintf(viewer," Jacobian is applied matrix-free with differencing, no explict Jacobian\n");
456: }
457: } else if (isstring) {
458: const char *type;
459: SNESGetType(snes,&type);
460: PetscViewerStringSPrintf(viewer," SNESType: %-7.7s",type);
461: if (snes->ops->view) {(*snes->ops->view)(snes,viewer);}
462: } else if (isbinary) {
463: PetscInt classid = SNES_FILE_CLASSID;
464: MPI_Comm comm;
465: PetscMPIInt rank;
466: char type[256];
468: PetscObjectGetComm((PetscObject)snes,&comm);
469: MPI_Comm_rank(comm,&rank);
470: if (!rank) {
471: PetscViewerBinaryWrite(viewer,&classid,1,PETSC_INT);
472: PetscStrncpy(type,((PetscObject)snes)->type_name,sizeof(type));
473: PetscViewerBinaryWrite(viewer,type,sizeof(type),PETSC_CHAR);
474: }
475: if (snes->ops->view) {
476: (*snes->ops->view)(snes,viewer);
477: }
478: } else if (isdraw) {
479: PetscDraw draw;
480: char str[36];
481: PetscReal x,y,bottom,h;
483: PetscViewerDrawGetDraw(viewer,0,&draw);
484: PetscDrawGetCurrentPoint(draw,&x,&y);
485: PetscStrncpy(str,"SNES: ",sizeof(str));
486: PetscStrlcat(str,((PetscObject)snes)->type_name,sizeof(str));
487: PetscDrawStringBoxed(draw,x,y,PETSC_DRAW_BLUE,PETSC_DRAW_BLACK,str,NULL,&h);
488: bottom = y - h;
489: PetscDrawPushCurrentPoint(draw,x,bottom);
490: if (snes->ops->view) {
491: (*snes->ops->view)(snes,viewer);
492: }
493: #if defined(PETSC_HAVE_SAWS)
494: } else if (issaws) {
495: PetscMPIInt rank;
496: const char *name;
498: PetscObjectGetName((PetscObject)snes,&name);
499: MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
500: if (!((PetscObject)snes)->amsmem && !rank) {
501: char dir[1024];
503: PetscObjectViewSAWs((PetscObject)snes,viewer);
504: PetscSNPrintf(dir,1024,"/PETSc/Objects/%s/its",name);
505: PetscStackCallSAWs(SAWs_Register,(dir,&snes->iter,1,SAWs_READ,SAWs_INT));
506: if (!snes->conv_hist) {
507: SNESSetConvergenceHistory(snes,NULL,NULL,PETSC_DECIDE,PETSC_TRUE);
508: }
509: PetscSNPrintf(dir,1024,"/PETSc/Objects/%s/conv_hist",name);
510: PetscStackCallSAWs(SAWs_Register,(dir,snes->conv_hist,10,SAWs_READ,SAWs_DOUBLE));
511: }
512: #endif
513: }
514: if (snes->linesearch) {
515: SNESGetLineSearch(snes, &linesearch);
516: PetscViewerASCIIPushTab(viewer);
517: SNESLineSearchView(linesearch, viewer);
518: PetscViewerASCIIPopTab(viewer);
519: }
520: if (snes->npc && snes->usesnpc) {
521: PetscViewerASCIIPushTab(viewer);
522: SNESView(snes->npc, viewer);
523: PetscViewerASCIIPopTab(viewer);
524: }
525: PetscViewerASCIIPushTab(viewer);
526: DMGetDMSNES(snes->dm,&dmsnes);
527: DMSNESView(dmsnes, viewer);
528: PetscViewerASCIIPopTab(viewer);
529: if (snes->usesksp) {
530: SNESGetKSP(snes,&ksp);
531: PetscViewerASCIIPushTab(viewer);
532: KSPView(ksp,viewer);
533: PetscViewerASCIIPopTab(viewer);
534: }
535: if (isdraw) {
536: PetscDraw draw;
537: PetscViewerDrawGetDraw(viewer,0,&draw);
538: PetscDrawPopCurrentPoint(draw);
539: }
540: return(0);
541: }
543: /*
544: We retain a list of functions that also take SNES command
545: line options. These are called at the end SNESSetFromOptions()
546: */
547: #define MAXSETFROMOPTIONS 5
548: static PetscInt numberofsetfromoptions;
549: static PetscErrorCode (*othersetfromoptions[MAXSETFROMOPTIONS])(SNES);
551: /*@C
552: SNESAddOptionsChecker - Adds an additional function to check for SNES options.
554: Not Collective
556: Input Parameter:
557: . snescheck - function that checks for options
559: Level: developer
561: .seealso: SNESSetFromOptions()
562: @*/
563: PetscErrorCode SNESAddOptionsChecker(PetscErrorCode (*snescheck)(SNES))
564: {
566: if (numberofsetfromoptions >= MAXSETFROMOPTIONS) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE, "Too many options checkers, only %D allowed", MAXSETFROMOPTIONS);
567: othersetfromoptions[numberofsetfromoptions++] = snescheck;
568: return(0);
569: }
571: PETSC_INTERN PetscErrorCode SNESDefaultMatrixFreeCreate2(SNES,Vec,Mat*);
573: static PetscErrorCode SNESSetUpMatrixFree_Private(SNES snes, PetscBool hasOperator, PetscInt version)
574: {
575: Mat J;
577: MatNullSpace nullsp;
582: if (!snes->vec_func && (snes->jacobian || snes->jacobian_pre)) {
583: Mat A = snes->jacobian, B = snes->jacobian_pre;
584: MatCreateVecs(A ? A : B, NULL,&snes->vec_func);
585: }
587: if (version == 1) {
588: MatCreateSNESMF(snes,&J);
589: MatMFFDSetOptionsPrefix(J,((PetscObject)snes)->prefix);
590: MatSetFromOptions(J);
591: } else if (version == 2) {
592: if (!snes->vec_func) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"SNESSetFunction() must be called first");
593: #if !defined(PETSC_USE_COMPLEX) && !defined(PETSC_USE_REAL_SINGLE) && !defined(PETSC_USE_REAL___FLOAT128) && !defined(PETSC_USE_REAL___FP16)
594: SNESDefaultMatrixFreeCreate2(snes,snes->vec_func,&J);
595: #else
596: SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP, "matrix-free operator routines (version 2)");
597: #endif
598: } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE, "matrix-free operator routines, only version 1 and 2");
600: /* attach any user provided null space that was on Amat to the newly created matrix free matrix */
601: if (snes->jacobian) {
602: MatGetNullSpace(snes->jacobian,&nullsp);
603: if (nullsp) {
604: MatSetNullSpace(J,nullsp);
605: }
606: }
608: PetscInfo1(snes,"Setting default matrix-free operator routines (version %D)\n", version);
609: if (hasOperator) {
611: /* This version replaces the user provided Jacobian matrix with a
612: matrix-free version but still employs the user-provided preconditioner matrix. */
613: SNESSetJacobian(snes,J,NULL,NULL,NULL);
614: } else {
615: /* This version replaces both the user-provided Jacobian and the user-
616: provided preconditioner Jacobian with the default matrix free version. */
617: if ((snes->npcside== PC_LEFT) && snes->npc) {
618: if (!snes->jacobian){SNESSetJacobian(snes,J,NULL,NULL,NULL);}
619: } else {
620: KSP ksp;
621: PC pc;
622: PetscBool match;
624: SNESSetJacobian(snes,J,J,MatMFFDComputeJacobian,NULL);
625: /* Force no preconditioner */
626: SNESGetKSP(snes,&ksp);
627: KSPGetPC(ksp,&pc);
628: PetscObjectTypeCompare((PetscObject)pc,PCSHELL,&match);
629: if (!match) {
630: PetscInfo(snes,"Setting default matrix-free preconditioner routines\nThat is no preconditioner is being used\n");
631: PCSetType(pc,PCNONE);
632: }
633: }
634: }
635: MatDestroy(&J);
636: return(0);
637: }
639: static PetscErrorCode DMRestrictHook_SNESVecSol(DM dmfine,Mat Restrict,Vec Rscale,Mat Inject,DM dmcoarse,void *ctx)
640: {
641: SNES snes = (SNES)ctx;
643: Vec Xfine,Xfine_named = NULL,Xcoarse;
646: if (PetscLogPrintInfo) {
647: PetscInt finelevel,coarselevel,fineclevel,coarseclevel;
648: DMGetRefineLevel(dmfine,&finelevel);
649: DMGetCoarsenLevel(dmfine,&fineclevel);
650: DMGetRefineLevel(dmcoarse,&coarselevel);
651: DMGetCoarsenLevel(dmcoarse,&coarseclevel);
652: PetscInfo4(dmfine,"Restricting SNES solution vector from level %D-%D to level %D-%D\n",finelevel,fineclevel,coarselevel,coarseclevel);
653: }
654: if (dmfine == snes->dm) Xfine = snes->vec_sol;
655: else {
656: DMGetNamedGlobalVector(dmfine,"SNESVecSol",&Xfine_named);
657: Xfine = Xfine_named;
658: }
659: DMGetNamedGlobalVector(dmcoarse,"SNESVecSol",&Xcoarse);
660: if (Inject) {
661: MatRestrict(Inject,Xfine,Xcoarse);
662: } else {
663: MatRestrict(Restrict,Xfine,Xcoarse);
664: VecPointwiseMult(Xcoarse,Xcoarse,Rscale);
665: }
666: DMRestoreNamedGlobalVector(dmcoarse,"SNESVecSol",&Xcoarse);
667: if (Xfine_named) {DMRestoreNamedGlobalVector(dmfine,"SNESVecSol",&Xfine_named);}
668: return(0);
669: }
671: static PetscErrorCode DMCoarsenHook_SNESVecSol(DM dm,DM dmc,void *ctx)
672: {
676: DMCoarsenHookAdd(dmc,DMCoarsenHook_SNESVecSol,DMRestrictHook_SNESVecSol,ctx);
677: return(0);
678: }
680: /* This may be called to rediscretize the operator on levels of linear multigrid. The DM shuffle is so the user can
681: * safely call SNESGetDM() in their residual evaluation routine. */
682: static PetscErrorCode KSPComputeOperators_SNES(KSP ksp,Mat A,Mat B,void *ctx)
683: {
684: SNES snes = (SNES)ctx;
686: Vec X,Xnamed = NULL;
687: DM dmsave;
688: void *ctxsave;
689: PetscErrorCode (*jac)(SNES,Vec,Mat,Mat,void*) = NULL;
692: dmsave = snes->dm;
693: KSPGetDM(ksp,&snes->dm);
694: if (dmsave == snes->dm) X = snes->vec_sol; /* We are on the finest level */
695: else { /* We are on a coarser level, this vec was initialized using a DM restrict hook */
696: DMGetNamedGlobalVector(snes->dm,"SNESVecSol",&Xnamed);
697: X = Xnamed;
698: SNESGetJacobian(snes,NULL,NULL,&jac,&ctxsave);
699: /* If the DM's don't match up, the MatFDColoring context needed for the jacobian won't match up either -- fixit. */
700: if (jac == SNESComputeJacobianDefaultColor) {
701: SNESSetJacobian(snes,NULL,NULL,SNESComputeJacobianDefaultColor,NULL);
702: }
703: }
704: /* Make sure KSP DM has the Jacobian computation routine */
705: {
706: DMSNES sdm;
708: DMGetDMSNES(snes->dm, &sdm);
709: if (!sdm->ops->computejacobian) {
710: DMCopyDMSNES(dmsave, snes->dm);
711: }
712: }
713: /* Compute the operators */
714: SNESComputeJacobian(snes,X,A,B);
715: /* Put the previous context back */
716: if (snes->dm != dmsave && jac == SNESComputeJacobianDefaultColor) {
717: SNESSetJacobian(snes,NULL,NULL,jac,ctxsave);
718: }
720: if (Xnamed) {DMRestoreNamedGlobalVector(snes->dm,"SNESVecSol",&Xnamed);}
721: snes->dm = dmsave;
722: return(0);
723: }
725: /*@
726: SNESSetUpMatrices - ensures that matrices are available for SNES, to be called by SNESSetUp_XXX()
728: Collective
730: Input Arguments:
731: . snes - snes to configure
733: Level: developer
735: .seealso: SNESSetUp()
736: @*/
737: PetscErrorCode SNESSetUpMatrices(SNES snes)
738: {
740: DM dm;
741: DMSNES sdm;
744: SNESGetDM(snes,&dm);
745: DMGetDMSNES(dm,&sdm);
746: if (!snes->jacobian && snes->mf) {
747: Mat J;
748: void *functx;
749: MatCreateSNESMF(snes,&J);
750: MatMFFDSetOptionsPrefix(J,((PetscObject)snes)->prefix);
751: MatSetFromOptions(J);
752: SNESGetFunction(snes,NULL,NULL,&functx);
753: SNESSetJacobian(snes,J,J,NULL,NULL);
754: MatDestroy(&J);
755: } else if (snes->mf_operator && !snes->jacobian_pre && !snes->jacobian) {
756: Mat J,B;
757: MatCreateSNESMF(snes,&J);
758: MatMFFDSetOptionsPrefix(J,((PetscObject)snes)->prefix);
759: MatSetFromOptions(J);
760: DMCreateMatrix(snes->dm,&B);
761: /* sdm->computejacobian was already set to reach here */
762: SNESSetJacobian(snes,J,B,NULL,NULL);
763: MatDestroy(&J);
764: MatDestroy(&B);
765: } else if (!snes->jacobian_pre) {
766: PetscErrorCode (*nspconstr)(DM, PetscInt, PetscInt, MatNullSpace *);
767: PetscDS prob;
768: Mat J, B;
769: MatNullSpace nullspace = NULL;
770: PetscBool hasPrec = PETSC_FALSE;
771: PetscInt Nf;
773: J = snes->jacobian;
774: DMGetDS(dm, &prob);
775: if (prob) {PetscDSHasJacobianPreconditioner(prob, &hasPrec);}
776: if (J) {PetscObjectReference((PetscObject) J);}
777: else if (hasPrec) {DMCreateMatrix(snes->dm, &J);}
778: DMCreateMatrix(snes->dm, &B);
779: PetscDSGetNumFields(prob, &Nf);
780: DMGetNullSpaceConstructor(snes->dm, Nf, &nspconstr);
781: if (nspconstr) (*nspconstr)(snes->dm, Nf, Nf, &nullspace);
782: MatSetNullSpace(B, nullspace);
783: MatNullSpaceDestroy(&nullspace);
784: SNESSetJacobian(snes, J ? J : B, B, NULL, NULL);
785: MatDestroy(&J);
786: MatDestroy(&B);
787: }
788: {
789: KSP ksp;
790: SNESGetKSP(snes,&ksp);
791: KSPSetComputeOperators(ksp,KSPComputeOperators_SNES,snes);
792: DMCoarsenHookAdd(snes->dm,DMCoarsenHook_SNESVecSol,DMRestrictHook_SNESVecSol,snes);
793: }
794: return(0);
795: }
797: /*@C
798: SNESMonitorSetFromOptions - Sets a monitor function and viewer appropriate for the type indicated by the user
800: Collective on SNES
802: Input Parameters:
803: + snes - SNES object you wish to monitor
804: . name - the monitor type one is seeking
805: . help - message indicating what monitoring is done
806: . manual - manual page for the monitor
807: . monitor - the monitor function
808: - 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
810: Level: developer
812: .seealso: PetscOptionsGetViewer(), PetscOptionsGetReal(), PetscOptionsHasName(), PetscOptionsGetString(),
813: PetscOptionsGetIntArray(), PetscOptionsGetRealArray(), PetscOptionsBool()
814: PetscOptionsInt(), PetscOptionsString(), PetscOptionsReal(), PetscOptionsBool(),
815: PetscOptionsName(), PetscOptionsBegin(), PetscOptionsEnd(), PetscOptionsHead(),
816: PetscOptionsStringArray(),PetscOptionsRealArray(), PetscOptionsScalar(),
817: PetscOptionsBoolGroupBegin(), PetscOptionsBoolGroup(), PetscOptionsBoolGroupEnd(),
818: PetscOptionsFList(), PetscOptionsEList()
819: @*/
820: PetscErrorCode SNESMonitorSetFromOptions(SNES snes,const char name[],const char help[], const char manual[],PetscErrorCode (*monitor)(SNES,PetscInt,PetscReal,PetscViewerAndFormat*),PetscErrorCode (*monitorsetup)(SNES,PetscViewerAndFormat*))
821: {
822: PetscErrorCode ierr;
823: PetscViewer viewer;
824: PetscViewerFormat format;
825: PetscBool flg;
828: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject) snes)->options,((PetscObject)snes)->prefix,name,&viewer,&format,&flg);
829: if (flg) {
830: PetscViewerAndFormat *vf;
831: PetscViewerAndFormatCreate(viewer,format,&vf);
832: PetscObjectDereference((PetscObject)viewer);
833: if (monitorsetup) {
834: (*monitorsetup)(snes,vf);
835: }
836: SNESMonitorSet(snes,(PetscErrorCode (*)(SNES,PetscInt,PetscReal,void*))monitor,vf,(PetscErrorCode (*)(void**))PetscViewerAndFormatDestroy);
837: }
838: return(0);
839: }
841: /*@
842: SNESSetFromOptions - Sets various SNES and KSP parameters from user options.
844: Collective on SNES
846: Input Parameter:
847: . snes - the SNES context
849: Options Database Keys:
850: + -snes_type <type> - newtonls, newtontr, ngmres, ncg, nrichardson, qn, vi, fas, SNESType for complete list
851: . -snes_stol - convergence tolerance in terms of the norm
852: of the change in the solution between steps
853: . -snes_atol <abstol> - absolute tolerance of residual norm
854: . -snes_rtol <rtol> - relative decrease in tolerance norm from initial
855: . -snes_divergence_tolerance <divtol> - if the residual goes above divtol*rnorm0, exit with divergence
856: . -snes_force_iteration <force> - force SNESSolve() to take at least one iteration
857: . -snes_max_it <max_it> - maximum number of iterations
858: . -snes_max_funcs <max_funcs> - maximum number of function evaluations
859: . -snes_max_fail <max_fail> - maximum number of line search failures allowed before stopping, default is none
860: . -snes_max_linear_solve_fail - number of linear solver failures before SNESSolve() stops
861: . -snes_lag_preconditioner <lag> - how often preconditioner is rebuilt (use -1 to never rebuild)
862: . -snes_lag_preconditioner_persists <true,false> - retains the -snes_lag_preconditioner information across multiple SNESSolve()
863: . -snes_lag_jacobian <lag> - how often Jacobian is rebuilt (use -1 to never rebuild)
864: . -snes_lag_jacobian_persists <true,false> - retains the -snes_lag_jacobian information across multiple SNESSolve()
865: . -snes_trtol <trtol> - trust region tolerance
866: . -snes_no_convergence_test - skip convergence test in nonlinear
867: solver; hence iterations will continue until max_it
868: or some other criterion is reached. Saves expense
869: of convergence test
870: . -snes_monitor [ascii][:filename][:viewer format] - prints residual norm at each iteration. if no filename given prints to stdout
871: . -snes_monitor_solution [ascii binary draw][:filename][:viewer format] - plots solution at each iteration
872: . -snes_monitor_residual [ascii binary draw][:filename][:viewer format] - plots residual (not its norm) at each iteration
873: . -snes_monitor_solution_update [ascii binary draw][:filename][:viewer format] - plots update to solution at each iteration
874: . -snes_monitor_lg_residualnorm - plots residual norm at each iteration
875: . -snes_monitor_lg_range - plots residual norm at each iteration
876: . -snes_fd - use finite differences to compute Jacobian; very slow, only for testing
877: . -snes_fd_color - use finite differences with coloring to compute Jacobian
878: . -snes_mf_ksp_monitor - if using matrix-free multiply then print h at each KSP iteration
879: . -snes_converged_reason - print the reason for convergence/divergence after each solve
880: - -npc_snes_type <type> - the SNES type to use as a nonlinear preconditioner
882: Options Database for Eisenstat-Walker method:
883: + -snes_ksp_ew - use Eisenstat-Walker method for determining linear system convergence
884: . -snes_ksp_ew_version ver - version of Eisenstat-Walker method
885: . -snes_ksp_ew_rtol0 <rtol0> - Sets rtol0
886: . -snes_ksp_ew_rtolmax <rtolmax> - Sets rtolmax
887: . -snes_ksp_ew_gamma <gamma> - Sets gamma
888: . -snes_ksp_ew_alpha <alpha> - Sets alpha
889: . -snes_ksp_ew_alpha2 <alpha2> - Sets alpha2
890: - -snes_ksp_ew_threshold <threshold> - Sets threshold
892: Notes:
893: To see all options, run your program with the -help option or consult the users manual
895: Notes:
896: SNES supports three approaches for computing (approximate) Jacobians: user provided via SNESSetJacobian(), matrix free, and computing explictly with
897: finite differences and coloring using MatFDColoring. It is also possible to use automatic differentiation and the MatFDColoring object.
899: Level: beginner
901: .seealso: SNESSetOptionsPrefix(), SNESResetFromOptions(), SNES, SNESCreate()
902: @*/
903: PetscErrorCode SNESSetFromOptions(SNES snes)
904: {
905: PetscBool flg,pcset,persist,set;
906: PetscInt i,indx,lag,grids;
907: const char *deft = SNESNEWTONLS;
908: const char *convtests[] = {"default","skip"};
909: SNESKSPEW *kctx = NULL;
910: char type[256], monfilename[PETSC_MAX_PATH_LEN];
912: PCSide pcside;
913: const char *optionsprefix;
917: SNESRegisterAll();
918: PetscObjectOptionsBegin((PetscObject)snes);
919: if (((PetscObject)snes)->type_name) deft = ((PetscObject)snes)->type_name;
920: PetscOptionsFList("-snes_type","Nonlinear solver method","SNESSetType",SNESList,deft,type,256,&flg);
921: if (flg) {
922: SNESSetType(snes,type);
923: } else if (!((PetscObject)snes)->type_name) {
924: SNESSetType(snes,deft);
925: }
926: PetscOptionsReal("-snes_stol","Stop if step length less than","SNESSetTolerances",snes->stol,&snes->stol,NULL);
927: PetscOptionsReal("-snes_atol","Stop if function norm less than","SNESSetTolerances",snes->abstol,&snes->abstol,NULL);
929: PetscOptionsReal("-snes_rtol","Stop if decrease in function norm less than","SNESSetTolerances",snes->rtol,&snes->rtol,NULL);
930: PetscOptionsReal("-snes_divergence_tolerance","Stop if residual norm increases by this factor","SNESSetDivergenceTolerance",snes->divtol,&snes->divtol,NULL);
931: PetscOptionsInt("-snes_max_it","Maximum iterations","SNESSetTolerances",snes->max_its,&snes->max_its,NULL);
932: PetscOptionsInt("-snes_max_funcs","Maximum function evaluations","SNESSetTolerances",snes->max_funcs,&snes->max_funcs,NULL);
933: PetscOptionsInt("-snes_max_fail","Maximum nonlinear step failures","SNESSetMaxNonlinearStepFailures",snes->maxFailures,&snes->maxFailures,NULL);
934: PetscOptionsInt("-snes_max_linear_solve_fail","Maximum failures in linear solves allowed","SNESSetMaxLinearSolveFailures",snes->maxLinearSolveFailures,&snes->maxLinearSolveFailures,NULL);
935: PetscOptionsBool("-snes_error_if_not_converged","Generate error if solver does not converge","SNESSetErrorIfNotConverged",snes->errorifnotconverged,&snes->errorifnotconverged,NULL);
936: PetscOptionsBool("-snes_force_iteration","Force SNESSolve() to take at least one iteration","SNESSetForceIteration",snes->forceiteration,&snes->forceiteration,NULL);
937: PetscOptionsBool("-snes_check_jacobian_domain_error","Check Jacobian domain error after Jacobian evaluation","SNESCheckJacobianDomainError",snes->checkjacdomainerror,&snes->checkjacdomainerror,NULL);
939: PetscOptionsInt("-snes_lag_preconditioner","How often to rebuild preconditioner","SNESSetLagPreconditioner",snes->lagpreconditioner,&lag,&flg);
940: if (flg) {
941: if (lag == -1) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_USER,"Cannot set the lag to -1 from the command line since the preconditioner must be built as least once, perhaps you mean -2");
942: SNESSetLagPreconditioner(snes,lag);
943: }
944: PetscOptionsBool("-snes_lag_preconditioner_persists","Preconditioner lagging through multiple SNES solves","SNESSetLagPreconditionerPersists",snes->lagjac_persist,&persist,&flg);
945: if (flg) {
946: SNESSetLagPreconditionerPersists(snes,persist);
947: }
948: PetscOptionsInt("-snes_lag_jacobian","How often to rebuild Jacobian","SNESSetLagJacobian",snes->lagjacobian,&lag,&flg);
949: if (flg) {
950: if (lag == -1) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_USER,"Cannot set the lag to -1 from the command line since the Jacobian must be built as least once, perhaps you mean -2");
951: SNESSetLagJacobian(snes,lag);
952: }
953: PetscOptionsBool("-snes_lag_jacobian_persists","Jacobian lagging through multiple SNES solves","SNESSetLagJacobianPersists",snes->lagjac_persist,&persist,&flg);
954: if (flg) {
955: SNESSetLagJacobianPersists(snes,persist);
956: }
958: PetscOptionsInt("-snes_grid_sequence","Use grid sequencing to generate initial guess","SNESSetGridSequence",snes->gridsequence,&grids,&flg);
959: if (flg) {
960: SNESSetGridSequence(snes,grids);
961: }
963: PetscOptionsEList("-snes_convergence_test","Convergence test","SNESSetConvergenceTest",convtests,2,"default",&indx,&flg);
964: if (flg) {
965: switch (indx) {
966: case 0: SNESSetConvergenceTest(snes,SNESConvergedDefault,NULL,NULL); break;
967: case 1: SNESSetConvergenceTest(snes,SNESConvergedSkip,NULL,NULL); break;
968: }
969: }
971: PetscOptionsEList("-snes_norm_schedule","SNES Norm schedule","SNESSetNormSchedule",SNESNormSchedules,5,"function",&indx,&flg);
972: if (flg) { SNESSetNormSchedule(snes,(SNESNormSchedule)indx); }
974: PetscOptionsEList("-snes_function_type","SNES Norm schedule","SNESSetFunctionType",SNESFunctionTypes,2,"unpreconditioned",&indx,&flg);
975: if (flg) { SNESSetFunctionType(snes,(SNESFunctionType)indx); }
977: kctx = (SNESKSPEW*)snes->kspconvctx;
979: PetscOptionsBool("-snes_ksp_ew","Use Eisentat-Walker linear system convergence test","SNESKSPSetUseEW",snes->ksp_ewconv,&snes->ksp_ewconv,NULL);
981: PetscOptionsInt("-snes_ksp_ew_version","Version 1, 2 or 3","SNESKSPSetParametersEW",kctx->version,&kctx->version,NULL);
982: PetscOptionsReal("-snes_ksp_ew_rtol0","0 <= rtol0 < 1","SNESKSPSetParametersEW",kctx->rtol_0,&kctx->rtol_0,NULL);
983: PetscOptionsReal("-snes_ksp_ew_rtolmax","0 <= rtolmax < 1","SNESKSPSetParametersEW",kctx->rtol_max,&kctx->rtol_max,NULL);
984: PetscOptionsReal("-snes_ksp_ew_gamma","0 <= gamma <= 1","SNESKSPSetParametersEW",kctx->gamma,&kctx->gamma,NULL);
985: PetscOptionsReal("-snes_ksp_ew_alpha","1 < alpha <= 2","SNESKSPSetParametersEW",kctx->alpha,&kctx->alpha,NULL);
986: PetscOptionsReal("-snes_ksp_ew_alpha2","alpha2","SNESKSPSetParametersEW",kctx->alpha2,&kctx->alpha2,NULL);
987: PetscOptionsReal("-snes_ksp_ew_threshold","0 < threshold < 1","SNESKSPSetParametersEW",kctx->threshold,&kctx->threshold,NULL);
989: flg = PETSC_FALSE;
990: PetscOptionsBool("-snes_monitor_cancel","Remove all monitors","SNESMonitorCancel",flg,&flg,&set);
991: if (set && flg) {SNESMonitorCancel(snes);}
993: SNESMonitorSetFromOptions(snes,"-snes_monitor","Monitor norm of function","SNESMonitorDefault",SNESMonitorDefault,NULL);
994: SNESMonitorSetFromOptions(snes,"-snes_monitor_short","Monitor norm of function with fewer digits","SNESMonitorDefaultShort",SNESMonitorDefaultShort,NULL);
995: SNESMonitorSetFromOptions(snes,"-snes_monitor_range","Monitor range of elements of function","SNESMonitorRange",SNESMonitorRange,NULL);
997: SNESMonitorSetFromOptions(snes,"-snes_monitor_ratio","Monitor ratios of the norm of function for consecutive steps","SNESMonitorRatio",SNESMonitorRatio,SNESMonitorRatioSetUp);
998: SNESMonitorSetFromOptions(snes,"-snes_monitor_field","Monitor norm of function (split into fields)","SNESMonitorDefaultField",SNESMonitorDefaultField,NULL);
999: SNESMonitorSetFromOptions(snes,"-snes_monitor_solution","View solution at each iteration","SNESMonitorSolution",SNESMonitorSolution,NULL);
1000: SNESMonitorSetFromOptions(snes,"-snes_monitor_solution_update","View correction at each iteration","SNESMonitorSolutionUpdate",SNESMonitorSolutionUpdate,NULL);
1001: SNESMonitorSetFromOptions(snes,"-snes_monitor_residual","View residual at each iteration","SNESMonitorResidual",SNESMonitorResidual,NULL);
1002: SNESMonitorSetFromOptions(snes,"-snes_monitor_jacupdate_spectrum","Print the change in the spectrum of the Jacobian","SNESMonitorJacUpdateSpectrum",SNESMonitorJacUpdateSpectrum,NULL);
1003: SNESMonitorSetFromOptions(snes,"-snes_monitor_fields","Monitor norm of function per field","SNESMonitorSet",SNESMonitorFields,NULL);
1005: PetscOptionsString("-snes_monitor_python","Use Python function","SNESMonitorSet",NULL,monfilename,sizeof(monfilename),&flg);
1006: if (flg) {PetscPythonMonitorSet((PetscObject)snes,monfilename);}
1008: flg = PETSC_FALSE;
1009: PetscOptionsBool("-snes_monitor_lg_residualnorm","Plot function norm at each iteration","SNESMonitorLGResidualNorm",flg,&flg,NULL);
1010: if (flg) {
1011: PetscDrawLG ctx;
1013: SNESMonitorLGCreate(PetscObjectComm((PetscObject)snes),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,400,300,&ctx);
1014: SNESMonitorSet(snes,SNESMonitorLGResidualNorm,ctx,(PetscErrorCode (*)(void**))PetscDrawLGDestroy);
1015: }
1016: flg = PETSC_FALSE;
1017: PetscOptionsBool("-snes_monitor_lg_range","Plot function range at each iteration","SNESMonitorLGRange",flg,&flg,NULL);
1018: if (flg) {
1019: PetscViewer ctx;
1021: PetscViewerDrawOpen(PetscObjectComm((PetscObject)snes),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,400,300,&ctx);
1022: SNESMonitorSet(snes,SNESMonitorLGRange,ctx,(PetscErrorCode (*)(void**))PetscViewerDestroy);
1023: }
1025: flg = PETSC_FALSE;
1026: PetscOptionsBool("-snes_fd","Use finite differences (slow) to compute Jacobian","SNESComputeJacobianDefault",flg,&flg,NULL);
1027: if (flg) {
1028: void *functx;
1029: DM dm;
1030: DMSNES sdm;
1031: SNESGetDM(snes,&dm);
1032: DMGetDMSNES(dm,&sdm);
1033: sdm->jacobianctx = NULL;
1034: SNESGetFunction(snes,NULL,NULL,&functx);
1035: SNESSetJacobian(snes,snes->jacobian,snes->jacobian_pre,SNESComputeJacobianDefault,functx);
1036: PetscInfo(snes,"Setting default finite difference Jacobian matrix\n");
1037: }
1039: flg = PETSC_FALSE;
1040: PetscOptionsBool("-snes_fd_function","Use finite differences (slow) to compute function from user objective","SNESObjectiveComputeFunctionDefaultFD",flg,&flg,NULL);
1041: if (flg) {
1042: SNESSetFunction(snes,NULL,SNESObjectiveComputeFunctionDefaultFD,NULL);
1043: }
1045: flg = PETSC_FALSE;
1046: PetscOptionsBool("-snes_fd_color","Use finite differences with coloring to compute Jacobian","SNESComputeJacobianDefaultColor",flg,&flg,NULL);
1047: if (flg) {
1048: DM dm;
1049: DMSNES sdm;
1050: SNESGetDM(snes,&dm);
1051: DMGetDMSNES(dm,&sdm);
1052: sdm->jacobianctx = NULL;
1053: SNESSetJacobian(snes,snes->jacobian,snes->jacobian_pre,SNESComputeJacobianDefaultColor,NULL);
1054: PetscInfo(snes,"Setting default finite difference coloring Jacobian matrix\n");
1055: }
1057: flg = PETSC_FALSE;
1058: PetscOptionsBool("-snes_mf_operator","Use a Matrix-Free Jacobian with user-provided preconditioner matrix","SNESSetUseMatrixFree",PETSC_FALSE,&snes->mf_operator,&flg);
1059: if (flg && snes->mf_operator) {
1060: snes->mf_operator = PETSC_TRUE;
1061: snes->mf = PETSC_TRUE;
1062: }
1063: flg = PETSC_FALSE;
1064: PetscOptionsBool("-snes_mf","Use a Matrix-Free Jacobian with no preconditioner matrix","SNESSetUseMatrixFree",PETSC_FALSE,&snes->mf,&flg);
1065: if (!flg && snes->mf_operator) snes->mf = PETSC_TRUE;
1066: PetscOptionsInt("-snes_mf_version","Matrix-Free routines version 1 or 2","None",snes->mf_version,&snes->mf_version,NULL);
1068: flg = PETSC_FALSE;
1069: SNESGetNPCSide(snes,&pcside);
1070: PetscOptionsEnum("-snes_npc_side","SNES nonlinear preconditioner side","SNESSetNPCSide",PCSides,(PetscEnum)pcside,(PetscEnum*)&pcside,&flg);
1071: if (flg) {SNESSetNPCSide(snes,pcside);}
1073: #if defined(PETSC_HAVE_SAWS)
1074: /*
1075: Publish convergence information using SAWs
1076: */
1077: flg = PETSC_FALSE;
1078: PetscOptionsBool("-snes_monitor_saws","Publish SNES progress using SAWs","SNESMonitorSet",flg,&flg,NULL);
1079: if (flg) {
1080: void *ctx;
1081: SNESMonitorSAWsCreate(snes,&ctx);
1082: SNESMonitorSet(snes,SNESMonitorSAWs,ctx,SNESMonitorSAWsDestroy);
1083: }
1084: #endif
1085: #if defined(PETSC_HAVE_SAWS)
1086: {
1087: PetscBool set;
1088: flg = PETSC_FALSE;
1089: PetscOptionsBool("-snes_saws_block","Block for SAWs at end of SNESSolve","PetscObjectSAWsBlock",((PetscObject)snes)->amspublishblock,&flg,&set);
1090: if (set) {
1091: PetscObjectSAWsSetBlock((PetscObject)snes,flg);
1092: }
1093: }
1094: #endif
1096: for (i = 0; i < numberofsetfromoptions; i++) {
1097: (*othersetfromoptions[i])(snes);
1098: }
1100: if (snes->ops->setfromoptions) {
1101: (*snes->ops->setfromoptions)(PetscOptionsObject,snes);
1102: }
1104: /* process any options handlers added with PetscObjectAddOptionsHandler() */
1105: PetscObjectProcessOptionsHandlers(PetscOptionsObject,(PetscObject)snes);
1106: PetscOptionsEnd();
1108: if (snes->linesearch) {
1109: SNESGetLineSearch(snes, &snes->linesearch);
1110: SNESLineSearchSetFromOptions(snes->linesearch);
1111: }
1113: if (snes->usesksp) {
1114: if (!snes->ksp) {SNESGetKSP(snes,&snes->ksp);}
1115: KSPSetOperators(snes->ksp,snes->jacobian,snes->jacobian_pre);
1116: KSPSetFromOptions(snes->ksp);
1117: }
1119: /* if user has set the SNES NPC type via options database, create it. */
1120: SNESGetOptionsPrefix(snes, &optionsprefix);
1121: PetscOptionsHasName(((PetscObject)snes)->options,optionsprefix, "-npc_snes_type", &pcset);
1122: if (pcset && (!snes->npc)) {
1123: SNESGetNPC(snes, &snes->npc);
1124: }
1125: if (snes->npc) {
1126: SNESSetFromOptions(snes->npc);
1127: }
1128: snes->setfromoptionscalled++;
1129: return(0);
1130: }
1132: /*@
1133: SNESResetFromOptions - Sets various SNES and KSP parameters from user options ONLY if the SNES was previously set from options
1135: Collective on SNES
1137: Input Parameter:
1138: . snes - the SNES context
1140: Level: beginner
1142: .seealso: SNESSetFromOptions(), SNESSetOptionsPrefix()
1143: @*/
1144: PetscErrorCode SNESResetFromOptions(SNES snes)
1145: {
1149: if (snes->setfromoptionscalled) {SNESSetFromOptions(snes);}
1150: return(0);
1151: }
1153: /*@C
1154: SNESSetComputeApplicationContext - Sets an optional function to compute a user-defined context for
1155: the nonlinear solvers.
1157: Logically Collective on SNES
1159: Input Parameters:
1160: + snes - the SNES context
1161: . compute - function to compute the context
1162: - destroy - function to destroy the context
1164: Level: intermediate
1166: Notes:
1167: This function is currently not available from Fortran.
1169: .seealso: SNESGetApplicationContext(), SNESSetComputeApplicationContext(), SNESGetApplicationContext()
1170: @*/
1171: PetscErrorCode SNESSetComputeApplicationContext(SNES snes,PetscErrorCode (*compute)(SNES,void**),PetscErrorCode (*destroy)(void**))
1172: {
1175: snes->ops->usercompute = compute;
1176: snes->ops->userdestroy = destroy;
1177: return(0);
1178: }
1180: /*@
1181: SNESSetApplicationContext - Sets the optional user-defined context for
1182: the nonlinear solvers.
1184: Logically Collective on SNES
1186: Input Parameters:
1187: + snes - the SNES context
1188: - usrP - optional user context
1190: Level: intermediate
1192: Fortran Notes:
1193: To use this from Fortran you must write a Fortran interface definition for this
1194: function that tells Fortran the Fortran derived data type that you are passing in as the ctx argument.
1196: .seealso: SNESGetApplicationContext()
1197: @*/
1198: PetscErrorCode SNESSetApplicationContext(SNES snes,void *usrP)
1199: {
1201: KSP ksp;
1205: SNESGetKSP(snes,&ksp);
1206: KSPSetApplicationContext(ksp,usrP);
1207: snes->user = usrP;
1208: return(0);
1209: }
1211: /*@
1212: SNESGetApplicationContext - Gets the user-defined context for the
1213: nonlinear solvers.
1215: Not Collective
1217: Input Parameter:
1218: . snes - SNES context
1220: Output Parameter:
1221: . usrP - user context
1223: Fortran Notes:
1224: To use this from Fortran you must write a Fortran interface definition for this
1225: function that tells Fortran the Fortran derived data type that you are passing in as the ctx argument.
1227: Level: intermediate
1229: .seealso: SNESSetApplicationContext()
1230: @*/
1231: PetscErrorCode SNESGetApplicationContext(SNES snes,void *usrP)
1232: {
1235: *(void**)usrP = snes->user;
1236: return(0);
1237: }
1239: /*@
1240: SNESSetUseMatrixFree - indicates that SNES should use matrix free finite difference matrix vector products internally to apply the Jacobian.
1242: Collective on SNES
1244: Input Parameters:
1245: + snes - SNES context
1246: . mf_operator - use matrix-free only for the Amat used by SNESSetJacobian(), this means the user provided Pmat will continue to be used
1247: - mf - use matrix-free for both the Amat and Pmat used by SNESSetJacobian(), both the Amat and Pmat set in SNESSetJacobian() will be ignored
1249: Options Database:
1250: + -snes_mf - use matrix free for both the mat and pmat operator
1251: . -snes_mf_operator - use matrix free only for the mat operator
1252: . -snes_fd_color - compute the Jacobian via coloring and finite differences.
1253: - -snes_fd - compute the Jacobian via finite differences (slow)
1255: Level: intermediate
1257: Notes:
1258: SNES supports three approaches for computing (approximate) Jacobians: user provided via SNESSetJacobian(), matrix free, and computing explictly with
1259: finite differences and coloring using MatFDColoring. It is also possible to use automatic differentiation and the MatFDColoring object.
1261: .seealso: SNESGetUseMatrixFree(), MatCreateSNESMF(), SNESComputeJacobianDefaultColor()
1262: @*/
1263: PetscErrorCode SNESSetUseMatrixFree(SNES snes,PetscBool mf_operator,PetscBool mf)
1264: {
1269: snes->mf = mf_operator ? PETSC_TRUE : mf;
1270: snes->mf_operator = mf_operator;
1271: return(0);
1272: }
1274: /*@
1275: SNESGetUseMatrixFree - indicates if the SNES uses matrix free finite difference matrix vector products to apply the Jacobian.
1277: Collective on SNES
1279: Input Parameter:
1280: . snes - SNES context
1282: Output Parameters:
1283: + mf_operator - use matrix-free only for the Amat used by SNESSetJacobian(), this means the user provided Pmat will continue to be used
1284: - mf - use matrix-free for both the Amat and Pmat used by SNESSetJacobian(), both the Amat and Pmat set in SNESSetJacobian() will be ignored
1286: Options Database:
1287: + -snes_mf - use matrix free for both the mat and pmat operator
1288: - -snes_mf_operator - use matrix free only for the mat operator
1290: Level: intermediate
1292: .seealso: SNESSetUseMatrixFree(), MatCreateSNESMF()
1293: @*/
1294: PetscErrorCode SNESGetUseMatrixFree(SNES snes,PetscBool *mf_operator,PetscBool *mf)
1295: {
1298: if (mf) *mf = snes->mf;
1299: if (mf_operator) *mf_operator = snes->mf_operator;
1300: return(0);
1301: }
1303: /*@
1304: SNESGetIterationNumber - Gets the number of nonlinear iterations completed
1305: at this time.
1307: Not Collective
1309: Input Parameter:
1310: . snes - SNES context
1312: Output Parameter:
1313: . iter - iteration number
1315: Notes:
1316: For example, during the computation of iteration 2 this would return 1.
1318: This is useful for using lagged Jacobians (where one does not recompute the
1319: Jacobian at each SNES iteration). For example, the code
1320: .vb
1321: SNESGetIterationNumber(snes,&it);
1322: if (!(it % 2)) {
1323: [compute Jacobian here]
1324: }
1325: .ve
1326: can be used in your ComputeJacobian() function to cause the Jacobian to be
1327: recomputed every second SNES iteration.
1329: After the SNES solve is complete this will return the number of nonlinear iterations used.
1331: Level: intermediate
1333: .seealso: SNESGetLinearSolveIterations()
1334: @*/
1335: PetscErrorCode SNESGetIterationNumber(SNES snes,PetscInt *iter)
1336: {
1340: *iter = snes->iter;
1341: return(0);
1342: }
1344: /*@
1345: SNESSetIterationNumber - Sets the current iteration number.
1347: Not Collective
1349: Input Parameter:
1350: + snes - SNES context
1351: - iter - iteration number
1353: Level: developer
1355: .seealso: SNESGetLinearSolveIterations()
1356: @*/
1357: PetscErrorCode SNESSetIterationNumber(SNES snes,PetscInt iter)
1358: {
1363: PetscObjectSAWsTakeAccess((PetscObject)snes);
1364: snes->iter = iter;
1365: PetscObjectSAWsGrantAccess((PetscObject)snes);
1366: return(0);
1367: }
1369: /*@
1370: SNESGetNonlinearStepFailures - Gets the number of unsuccessful steps
1371: attempted by the nonlinear solver.
1373: Not Collective
1375: Input Parameter:
1376: . snes - SNES context
1378: Output Parameter:
1379: . nfails - number of unsuccessful steps attempted
1381: Notes:
1382: This counter is reset to zero for each successive call to SNESSolve().
1384: Level: intermediate
1386: .seealso: SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures(), SNESGetLinearSolveFailures(),
1387: SNESSetMaxNonlinearStepFailures(), SNESGetMaxNonlinearStepFailures()
1388: @*/
1389: PetscErrorCode SNESGetNonlinearStepFailures(SNES snes,PetscInt *nfails)
1390: {
1394: *nfails = snes->numFailures;
1395: return(0);
1396: }
1398: /*@
1399: SNESSetMaxNonlinearStepFailures - Sets the maximum number of unsuccessful steps
1400: attempted by the nonlinear solver before it gives up.
1402: Not Collective
1404: Input Parameters:
1405: + snes - SNES context
1406: - maxFails - maximum of unsuccessful steps
1408: Level: intermediate
1410: .seealso: SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures(), SNESGetLinearSolveFailures(),
1411: SNESGetMaxNonlinearStepFailures(), SNESGetNonlinearStepFailures()
1412: @*/
1413: PetscErrorCode SNESSetMaxNonlinearStepFailures(SNES snes, PetscInt maxFails)
1414: {
1417: snes->maxFailures = maxFails;
1418: return(0);
1419: }
1421: /*@
1422: SNESGetMaxNonlinearStepFailures - Gets the maximum number of unsuccessful steps
1423: attempted by the nonlinear solver before it gives up.
1425: Not Collective
1427: Input Parameter:
1428: . snes - SNES context
1430: Output Parameter:
1431: . maxFails - maximum of unsuccessful steps
1433: Level: intermediate
1435: .seealso: SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures(), SNESGetLinearSolveFailures(),
1436: SNESSetMaxNonlinearStepFailures(), SNESGetNonlinearStepFailures()
1438: @*/
1439: PetscErrorCode SNESGetMaxNonlinearStepFailures(SNES snes, PetscInt *maxFails)
1440: {
1444: *maxFails = snes->maxFailures;
1445: return(0);
1446: }
1448: /*@
1449: SNESGetNumberFunctionEvals - Gets the number of user provided function evaluations
1450: done by SNES.
1452: Not Collective
1454: Input Parameter:
1455: . snes - SNES context
1457: Output Parameter:
1458: . nfuncs - number of evaluations
1460: Level: intermediate
1462: Notes:
1463: Reset every time SNESSolve is called unless SNESSetCountersReset() is used.
1465: .seealso: SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures(), SNESGetLinearSolveFailures(), SNESSetCountersReset()
1466: @*/
1467: PetscErrorCode SNESGetNumberFunctionEvals(SNES snes, PetscInt *nfuncs)
1468: {
1472: *nfuncs = snes->nfuncs;
1473: return(0);
1474: }
1476: /*@
1477: SNESGetLinearSolveFailures - Gets the number of failed (non-converged)
1478: linear solvers.
1480: Not Collective
1482: Input Parameter:
1483: . snes - SNES context
1485: Output Parameter:
1486: . nfails - number of failed solves
1488: Level: intermediate
1490: Options Database Keys:
1491: . -snes_max_linear_solve_fail <num> - The number of failures before the solve is terminated
1493: Notes:
1494: This counter is reset to zero for each successive call to SNESSolve().
1496: .seealso: SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures()
1497: @*/
1498: PetscErrorCode SNESGetLinearSolveFailures(SNES snes,PetscInt *nfails)
1499: {
1503: *nfails = snes->numLinearSolveFailures;
1504: return(0);
1505: }
1507: /*@
1508: SNESSetMaxLinearSolveFailures - the number of failed linear solve attempts
1509: allowed before SNES returns with a diverged reason of SNES_DIVERGED_LINEAR_SOLVE
1511: Logically Collective on SNES
1513: Input Parameters:
1514: + snes - SNES context
1515: - maxFails - maximum allowed linear solve failures
1517: Level: intermediate
1519: Options Database Keys:
1520: . -snes_max_linear_solve_fail <num> - The number of failures before the solve is terminated
1522: Notes:
1523: By default this is 0; that is SNES returns on the first failed linear solve
1525: .seealso: SNESGetLinearSolveFailures(), SNESGetMaxLinearSolveFailures(), SNESGetLinearSolveIterations()
1526: @*/
1527: PetscErrorCode SNESSetMaxLinearSolveFailures(SNES snes, PetscInt maxFails)
1528: {
1532: snes->maxLinearSolveFailures = maxFails;
1533: return(0);
1534: }
1536: /*@
1537: SNESGetMaxLinearSolveFailures - gets the maximum number of linear solve failures that
1538: are allowed before SNES terminates
1540: Not Collective
1542: Input Parameter:
1543: . snes - SNES context
1545: Output Parameter:
1546: . maxFails - maximum of unsuccessful solves allowed
1548: Level: intermediate
1550: Notes:
1551: By default this is 1; that is SNES returns on the first failed linear solve
1553: .seealso: SNESGetLinearSolveFailures(), SNESGetLinearSolveIterations(), SNESSetMaxLinearSolveFailures(),
1554: @*/
1555: PetscErrorCode SNESGetMaxLinearSolveFailures(SNES snes, PetscInt *maxFails)
1556: {
1560: *maxFails = snes->maxLinearSolveFailures;
1561: return(0);
1562: }
1564: /*@
1565: SNESGetLinearSolveIterations - Gets the total number of linear iterations
1566: used by the nonlinear solver.
1568: Not Collective
1570: Input Parameter:
1571: . snes - SNES context
1573: Output Parameter:
1574: . lits - number of linear iterations
1576: Notes:
1577: This counter is reset to zero for each successive call to SNESSolve() unless SNESSetCountersReset() is used.
1579: 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
1580: then call KSPGetIterationNumber() after the failed solve.
1582: Level: intermediate
1584: .seealso: SNESGetIterationNumber(), SNESGetLinearSolveFailures(), SNESGetMaxLinearSolveFailures(), SNESSetCountersReset()
1585: @*/
1586: PetscErrorCode SNESGetLinearSolveIterations(SNES snes,PetscInt *lits)
1587: {
1591: *lits = snes->linear_its;
1592: return(0);
1593: }
1595: /*@
1596: SNESSetCountersReset - Sets whether or not the counters for linear iterations and function evaluations
1597: are reset every time SNESSolve() is called.
1599: Logically Collective on SNES
1601: Input Parameter:
1602: + snes - SNES context
1603: - reset - whether to reset the counters or not
1605: Notes:
1606: This defaults to PETSC_TRUE
1608: Level: developer
1610: .seealso: SNESGetNumberFunctionEvals(), SNESGetLinearSolveIterations(), SNESGetNPC()
1611: @*/
1612: PetscErrorCode SNESSetCountersReset(SNES snes,PetscBool reset)
1613: {
1617: snes->counters_reset = reset;
1618: return(0);
1619: }
1622: /*@
1623: SNESSetKSP - Sets a KSP context for the SNES object to use
1625: Not Collective, but the SNES and KSP objects must live on the same MPI_Comm
1627: Input Parameters:
1628: + snes - the SNES context
1629: - ksp - the KSP context
1631: Notes:
1632: The SNES object already has its KSP object, you can obtain with SNESGetKSP()
1633: so this routine is rarely needed.
1635: The KSP object that is already in the SNES object has its reference count
1636: decreased by one.
1638: Level: developer
1640: .seealso: KSPGetPC(), SNESCreate(), KSPCreate(), SNESSetKSP()
1641: @*/
1642: PetscErrorCode SNESSetKSP(SNES snes,KSP ksp)
1643: {
1650: PetscObjectReference((PetscObject)ksp);
1651: if (snes->ksp) {PetscObjectDereference((PetscObject)snes->ksp);}
1652: snes->ksp = ksp;
1653: return(0);
1654: }
1656: /* -----------------------------------------------------------*/
1657: /*@
1658: SNESCreate - Creates a nonlinear solver context.
1660: Collective
1662: Input Parameters:
1663: . comm - MPI communicator
1665: Output Parameter:
1666: . outsnes - the new SNES context
1668: Options Database Keys:
1669: + -snes_mf - Activates default matrix-free Jacobian-vector products,
1670: and no preconditioning matrix
1671: . -snes_mf_operator - Activates default matrix-free Jacobian-vector
1672: products, and a user-provided preconditioning matrix
1673: as set by SNESSetJacobian()
1674: - -snes_fd - Uses (slow!) finite differences to compute Jacobian
1676: Level: beginner
1678: Developer Notes:
1679: SNES always creates a KSP object even though many SNES methods do not use it. This is
1680: unfortunate and should be fixed at some point. The flag snes->usesksp indicates if the
1681: particular method does use KSP and regulates if the information about the KSP is printed
1682: in SNESView(). TSSetFromOptions() does call SNESSetFromOptions() which can lead to users being confused
1683: by help messages about meaningless SNES options.
1685: SNES always creates the snes->kspconvctx even though it is used by only one type. This should
1686: be fixed.
1688: .seealso: SNESSolve(), SNESDestroy(), SNES, SNESSetLagPreconditioner(), SNESSetLagJacobian()
1690: @*/
1691: PetscErrorCode SNESCreate(MPI_Comm comm,SNES *outsnes)
1692: {
1694: SNES snes;
1695: SNESKSPEW *kctx;
1699: *outsnes = NULL;
1700: SNESInitializePackage();
1702: PetscHeaderCreate(snes,SNES_CLASSID,"SNES","Nonlinear solver","SNES",comm,SNESDestroy,SNESView);
1704: snes->ops->converged = SNESConvergedDefault;
1705: snes->usesksp = PETSC_TRUE;
1706: snes->tolerancesset = PETSC_FALSE;
1707: snes->max_its = 50;
1708: snes->max_funcs = 10000;
1709: snes->norm = 0.0;
1710: snes->xnorm = 0.0;
1711: snes->ynorm = 0.0;
1712: snes->normschedule = SNES_NORM_ALWAYS;
1713: snes->functype = SNES_FUNCTION_DEFAULT;
1714: #if defined(PETSC_USE_REAL_SINGLE)
1715: snes->rtol = 1.e-5;
1716: #else
1717: snes->rtol = 1.e-8;
1718: #endif
1719: snes->ttol = 0.0;
1720: #if defined(PETSC_USE_REAL_SINGLE)
1721: snes->abstol = 1.e-25;
1722: #else
1723: snes->abstol = 1.e-50;
1724: #endif
1725: #if defined(PETSC_USE_REAL_SINGLE)
1726: snes->stol = 1.e-5;
1727: #else
1728: snes->stol = 1.e-8;
1729: #endif
1730: #if defined(PETSC_USE_REAL_SINGLE)
1731: snes->deltatol = 1.e-6;
1732: #else
1733: snes->deltatol = 1.e-12;
1734: #endif
1735: snes->divtol = 1.e4;
1736: snes->rnorm0 = 0;
1737: snes->nfuncs = 0;
1738: snes->numFailures = 0;
1739: snes->maxFailures = 1;
1740: snes->linear_its = 0;
1741: snes->lagjacobian = 1;
1742: snes->jac_iter = 0;
1743: snes->lagjac_persist = PETSC_FALSE;
1744: snes->lagpreconditioner = 1;
1745: snes->pre_iter = 0;
1746: snes->lagpre_persist = PETSC_FALSE;
1747: snes->numbermonitors = 0;
1748: snes->data = NULL;
1749: snes->setupcalled = PETSC_FALSE;
1750: snes->ksp_ewconv = PETSC_FALSE;
1751: snes->nwork = 0;
1752: snes->work = NULL;
1753: snes->nvwork = 0;
1754: snes->vwork = NULL;
1755: snes->conv_hist_len = 0;
1756: snes->conv_hist_max = 0;
1757: snes->conv_hist = NULL;
1758: snes->conv_hist_its = NULL;
1759: snes->conv_hist_reset = PETSC_TRUE;
1760: snes->counters_reset = PETSC_TRUE;
1761: snes->vec_func_init_set = PETSC_FALSE;
1762: snes->reason = SNES_CONVERGED_ITERATING;
1763: snes->npcside = PC_RIGHT;
1764: snes->setfromoptionscalled = 0;
1766: snes->mf = PETSC_FALSE;
1767: snes->mf_operator = PETSC_FALSE;
1768: snes->mf_version = 1;
1770: snes->numLinearSolveFailures = 0;
1771: snes->maxLinearSolveFailures = 1;
1773: snes->vizerotolerance = 1.e-8;
1774: snes->checkjacdomainerror = PetscDefined(USE_DEBUG) ? PETSC_TRUE : PETSC_FALSE;
1776: /* Set this to true if the implementation of SNESSolve_XXX does compute the residual at the final solution. */
1777: snes->alwayscomputesfinalresidual = PETSC_FALSE;
1779: /* Create context to compute Eisenstat-Walker relative tolerance for KSP */
1780: PetscNewLog(snes,&kctx);
1782: snes->kspconvctx = (void*)kctx;
1783: kctx->version = 2;
1784: kctx->rtol_0 = .3; /* Eisenstat and Walker suggest rtol_0=.5, but
1785: this was too large for some test cases */
1786: kctx->rtol_last = 0.0;
1787: kctx->rtol_max = .9;
1788: kctx->gamma = 1.0;
1789: kctx->alpha = .5*(1.0 + PetscSqrtReal(5.0));
1790: kctx->alpha2 = kctx->alpha;
1791: kctx->threshold = .1;
1792: kctx->lresid_last = 0.0;
1793: kctx->norm_last = 0.0;
1795: *outsnes = snes;
1796: return(0);
1797: }
1799: /*MC
1800: SNESFunction - Functional form used to convey the nonlinear function to be solved by SNES
1802: Synopsis:
1803: #include "petscsnes.h"
1804: PetscErrorCode SNESFunction(SNES snes,Vec x,Vec f,void *ctx);
1806: Collective on snes
1808: Input Parameters:
1809: + snes - the SNES context
1810: . x - state at which to evaluate residual
1811: - ctx - optional user-defined function context, passed in with SNESSetFunction()
1813: Output Parameter:
1814: . f - vector to put residual (function value)
1816: Level: intermediate
1818: .seealso: SNESSetFunction(), SNESGetFunction()
1819: M*/
1821: /*@C
1822: SNESSetFunction - Sets the function evaluation routine and function
1823: vector for use by the SNES routines in solving systems of nonlinear
1824: equations.
1826: Logically Collective on SNES
1828: Input Parameters:
1829: + snes - the SNES context
1830: . r - vector to store function value
1831: . f - function evaluation routine; see SNESFunction for calling sequence details
1832: - ctx - [optional] user-defined context for private data for the
1833: function evaluation routine (may be NULL)
1835: Notes:
1836: The Newton-like methods typically solve linear systems of the form
1837: $ f'(x) x = -f(x),
1838: where f'(x) denotes the Jacobian matrix and f(x) is the function.
1840: Level: beginner
1842: .seealso: SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESSetPicard(), SNESFunction
1843: @*/
1844: PetscErrorCode SNESSetFunction(SNES snes,Vec r,PetscErrorCode (*f)(SNES,Vec,Vec,void*),void *ctx)
1845: {
1847: DM dm;
1851: if (r) {
1854: PetscObjectReference((PetscObject)r);
1855: VecDestroy(&snes->vec_func);
1857: snes->vec_func = r;
1858: }
1859: SNESGetDM(snes,&dm);
1860: DMSNESSetFunction(dm,f,ctx);
1861: return(0);
1862: }
1865: /*@C
1866: SNESSetInitialFunction - Sets the function vector to be used as the
1867: function norm at the initialization of the method. In some
1868: instances, the user has precomputed the function before calling
1869: SNESSolve. This function allows one to avoid a redundant call
1870: to SNESComputeFunction in that case.
1872: Logically Collective on SNES
1874: Input Parameters:
1875: + snes - the SNES context
1876: - f - vector to store function value
1878: Notes:
1879: This should not be modified during the solution procedure.
1881: This is used extensively in the SNESFAS hierarchy and in nonlinear preconditioning.
1883: Level: developer
1885: .seealso: SNESSetFunction(), SNESComputeFunction(), SNESSetInitialFunctionNorm()
1886: @*/
1887: PetscErrorCode SNESSetInitialFunction(SNES snes, Vec f)
1888: {
1890: Vec vec_func;
1896: if (snes->npcside== PC_LEFT && snes->functype == SNES_FUNCTION_PRECONDITIONED) {
1897: snes->vec_func_init_set = PETSC_FALSE;
1898: return(0);
1899: }
1900: SNESGetFunction(snes,&vec_func,NULL,NULL);
1901: VecCopy(f, vec_func);
1903: snes->vec_func_init_set = PETSC_TRUE;
1904: return(0);
1905: }
1907: /*@
1908: SNESSetNormSchedule - Sets the SNESNormSchedule used in covergence and monitoring
1909: of the SNES method.
1911: Logically Collective on SNES
1913: Input Parameters:
1914: + snes - the SNES context
1915: - normschedule - the frequency of norm computation
1917: Options Database Key:
1918: . -snes_norm_schedule <none, always, initialonly, finalonly, initalfinalonly>
1920: Notes:
1921: Only certain SNES methods support certain SNESNormSchedules. Most require evaluation
1922: of the nonlinear function and the taking of its norm at every iteration to
1923: even ensure convergence at all. However, methods such as custom Gauss-Seidel methods
1924: (SNESNGS) and the like do not require the norm of the function to be computed, and therfore
1925: may either be monitored for convergence or not. As these are often used as nonlinear
1926: preconditioners, monitoring the norm of their error is not a useful enterprise within
1927: their solution.
1929: Level: developer
1931: .seealso: SNESGetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
1932: @*/
1933: PetscErrorCode SNESSetNormSchedule(SNES snes, SNESNormSchedule normschedule)
1934: {
1937: snes->normschedule = normschedule;
1938: return(0);
1939: }
1942: /*@
1943: SNESGetNormSchedule - Gets the SNESNormSchedule used in covergence and monitoring
1944: of the SNES method.
1946: Logically Collective on SNES
1948: Input Parameters:
1949: + snes - the SNES context
1950: - normschedule - the type of the norm used
1952: Level: advanced
1954: .seealso: SNESSetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
1955: @*/
1956: PetscErrorCode SNESGetNormSchedule(SNES snes, SNESNormSchedule *normschedule)
1957: {
1960: *normschedule = snes->normschedule;
1961: return(0);
1962: }
1965: /*@
1966: SNESSetFunctionNorm - Sets the last computed residual norm.
1968: Logically Collective on SNES
1970: Input Parameters:
1971: + snes - the SNES context
1973: - normschedule - the frequency of norm computation
1975: Level: developer
1977: .seealso: SNESGetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
1978: @*/
1979: PetscErrorCode SNESSetFunctionNorm(SNES snes, PetscReal norm)
1980: {
1983: snes->norm = norm;
1984: return(0);
1985: }
1987: /*@
1988: SNESGetFunctionNorm - Gets the last computed norm of the residual
1990: Not Collective
1992: Input Parameter:
1993: . snes - the SNES context
1995: Output Parameter:
1996: . norm - the last computed residual norm
1998: Level: developer
2000: .seealso: SNESSetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
2001: @*/
2002: PetscErrorCode SNESGetFunctionNorm(SNES snes, PetscReal *norm)
2003: {
2007: *norm = snes->norm;
2008: return(0);
2009: }
2011: /*@
2012: SNESGetUpdateNorm - Gets the last computed norm of the Newton update
2014: Not Collective
2016: Input Parameter:
2017: . snes - the SNES context
2019: Output Parameter:
2020: . ynorm - the last computed update norm
2022: Level: developer
2024: .seealso: SNESSetNormSchedule(), SNESComputeFunction(), SNESGetFunctionNorm()
2025: @*/
2026: PetscErrorCode SNESGetUpdateNorm(SNES snes, PetscReal *ynorm)
2027: {
2031: *ynorm = snes->ynorm;
2032: return(0);
2033: }
2035: /*@
2036: SNESGetSolutionNorm - Gets the last computed norm of the solution
2038: Not Collective
2040: Input Parameter:
2041: . snes - the SNES context
2043: Output Parameter:
2044: . xnorm - the last computed solution norm
2046: Level: developer
2048: .seealso: SNESSetNormSchedule(), SNESComputeFunction(), SNESGetFunctionNorm(), SNESGetUpdateNorm()
2049: @*/
2050: PetscErrorCode SNESGetSolutionNorm(SNES snes, PetscReal *xnorm)
2051: {
2055: *xnorm = snes->xnorm;
2056: return(0);
2057: }
2059: /*@C
2060: SNESSetFunctionType - Sets the SNESNormSchedule used in covergence and monitoring
2061: of the SNES method.
2063: Logically Collective on SNES
2065: Input Parameters:
2066: + snes - the SNES context
2067: - normschedule - the frequency of norm computation
2069: Notes:
2070: Only certain SNES methods support certain SNESNormSchedules. Most require evaluation
2071: of the nonlinear function and the taking of its norm at every iteration to
2072: even ensure convergence at all. However, methods such as custom Gauss-Seidel methods
2073: (SNESNGS) and the like do not require the norm of the function to be computed, and therfore
2074: may either be monitored for convergence or not. As these are often used as nonlinear
2075: preconditioners, monitoring the norm of their error is not a useful enterprise within
2076: their solution.
2078: Level: developer
2080: .seealso: SNESGetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
2081: @*/
2082: PetscErrorCode SNESSetFunctionType(SNES snes, SNESFunctionType type)
2083: {
2086: snes->functype = type;
2087: return(0);
2088: }
2091: /*@C
2092: SNESGetFunctionType - Gets the SNESNormSchedule used in covergence and monitoring
2093: of the SNES method.
2095: Logically Collective on SNES
2097: Input Parameters:
2098: + snes - the SNES context
2099: - normschedule - the type of the norm used
2101: Level: advanced
2103: .seealso: SNESSetNormSchedule(), SNESComputeFunction(), VecNorm(), SNESSetFunction(), SNESSetInitialFunction(), SNESNormSchedule
2104: @*/
2105: PetscErrorCode SNESGetFunctionType(SNES snes, SNESFunctionType *type)
2106: {
2109: *type = snes->functype;
2110: return(0);
2111: }
2113: /*MC
2114: SNESNGSFunction - function used to convey a Gauss-Seidel sweep on the nonlinear function
2116: Synopsis:
2117: #include <petscsnes.h>
2118: $ SNESNGSFunction(SNES snes,Vec x,Vec b,void *ctx);
2120: Collective on snes
2122: Input Parameters:
2123: + X - solution vector
2124: . B - RHS vector
2125: - ctx - optional user-defined Gauss-Seidel context
2127: Output Parameter:
2128: . X - solution vector
2130: Level: intermediate
2132: .seealso: SNESSetNGS(), SNESGetNGS()
2133: M*/
2135: /*@C
2136: SNESSetNGS - Sets the user nonlinear Gauss-Seidel routine for
2137: use with composed nonlinear solvers.
2139: Input Parameters:
2140: + snes - the SNES context
2141: . f - function evaluation routine to apply Gauss-Seidel see SNESNGSFunction
2142: - ctx - [optional] user-defined context for private data for the
2143: smoother evaluation routine (may be NULL)
2145: Notes:
2146: The NGS routines are used by the composed nonlinear solver to generate
2147: a problem appropriate update to the solution, particularly FAS.
2149: Level: intermediate
2151: .seealso: SNESGetFunction(), SNESComputeNGS()
2152: @*/
2153: PetscErrorCode SNESSetNGS(SNES snes,PetscErrorCode (*f)(SNES,Vec,Vec,void*),void *ctx)
2154: {
2156: DM dm;
2160: SNESGetDM(snes,&dm);
2161: DMSNESSetNGS(dm,f,ctx);
2162: return(0);
2163: }
2165: PetscErrorCode SNESPicardComputeFunction(SNES snes,Vec x,Vec f,void *ctx)
2166: {
2168: DM dm;
2169: DMSNES sdm;
2172: SNESGetDM(snes,&dm);
2173: DMGetDMSNES(dm,&sdm);
2174: if (!sdm->ops->computepfunction) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Must call SNESSetPicard() to provide Picard function.");
2175: if (!sdm->ops->computepjacobian) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Must call SNESSetPicard() to provide Picard Jacobian.");
2176: /* A(x)*x - b(x) */
2177: PetscStackPush("SNES Picard user function");
2178: (*sdm->ops->computepfunction)(snes,x,f,sdm->pctx);
2179: PetscStackPop;
2180: PetscStackPush("SNES Picard user Jacobian");
2181: (*sdm->ops->computepjacobian)(snes,x,snes->jacobian,snes->jacobian_pre,sdm->pctx);
2182: PetscStackPop;
2183: VecScale(f,-1.0);
2184: MatMultAdd(snes->jacobian,x,f,f);
2185: return(0);
2186: }
2188: PetscErrorCode SNESPicardComputeJacobian(SNES snes,Vec x1,Mat J,Mat B,void *ctx)
2189: {
2191: /* the jacobian matrix should be pre-filled in SNESPicardComputeFunction */
2192: return(0);
2193: }
2195: /*@C
2196: SNESSetPicard - Use SNES to solve the semilinear-system A(x) x = b(x) via a Picard type iteration (Picard linearization)
2198: Logically Collective on SNES
2200: Input Parameters:
2201: + snes - the SNES context
2202: . r - vector to store function value
2203: . b - function evaluation routine
2204: . Amat - matrix with which A(x) x - b(x) is to be computed
2205: . Pmat - matrix from which preconditioner is computed (usually the same as Amat)
2206: . J - function to compute matrix value, see SNESJacobianFunction for details on its calling sequence
2207: - ctx - [optional] user-defined context for private data for the
2208: function evaluation routine (may be NULL)
2210: Notes:
2211: 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
2212: 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.
2214: One can call SNESSetPicard() or SNESSetFunction() (and possibly SNESSetJacobian()) but cannot call both
2216: $ 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}
2217: $ Note that when an exact solver is used this corresponds to the "classic" Picard A(x^{n}) x^{n+1} = b(x^{n}) iteration.
2219: Run with -snes_mf_operator to solve the system with Newton's method using A(x^{n}) to construct the preconditioner.
2221: We implement the defect correction form of the Picard iteration because it converges much more generally when inexact linear solvers are used then
2222: the direct Picard iteration A(x^n) x^{n+1} = b(x^n)
2224: 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
2225: 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
2226: different please contact us at petsc-dev@mcs.anl.gov and we'll have an entirely new argument :-).
2228: Level: intermediate
2230: .seealso: SNESGetFunction(), SNESSetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESGetPicard(), SNESLineSearchPreCheckPicard(), SNESJacobianFunction
2231: @*/
2232: 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)
2233: {
2235: DM dm;
2239: SNESGetDM(snes, &dm);
2240: DMSNESSetPicard(dm,b,J,ctx);
2241: SNESSetFunction(snes,r,SNESPicardComputeFunction,ctx);
2242: SNESSetJacobian(snes,Amat,Pmat,SNESPicardComputeJacobian,ctx);
2243: return(0);
2244: }
2246: /*@C
2247: SNESGetPicard - Returns the context for the Picard iteration
2249: Not Collective, but Vec is parallel if SNES is parallel. Collective if Vec is requested, but has not been created yet.
2251: Input Parameter:
2252: . snes - the SNES context
2254: Output Parameter:
2255: + r - the function (or NULL)
2256: . f - the function (or NULL); see SNESFunction for calling sequence details
2257: . Amat - the matrix used to defined the operation A(x) x - b(x) (or NULL)
2258: . Pmat - the matrix from which the preconditioner will be constructed (or NULL)
2259: . J - the function for matrix evaluation (or NULL); see SNESJacobianFunction for calling sequence details
2260: - ctx - the function context (or NULL)
2262: Level: advanced
2264: .seealso: SNESSetPicard(), SNESGetFunction(), SNESGetJacobian(), SNESGetDM(), SNESFunction, SNESJacobianFunction
2265: @*/
2266: 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)
2267: {
2269: DM dm;
2273: SNESGetFunction(snes,r,NULL,NULL);
2274: SNESGetJacobian(snes,Amat,Pmat,NULL,NULL);
2275: SNESGetDM(snes,&dm);
2276: DMSNESGetPicard(dm,f,J,ctx);
2277: return(0);
2278: }
2280: /*@C
2281: SNESSetComputeInitialGuess - Sets a routine used to compute an initial guess for the problem
2283: Logically Collective on SNES
2285: Input Parameters:
2286: + snes - the SNES context
2287: . func - function evaluation routine
2288: - ctx - [optional] user-defined context for private data for the
2289: function evaluation routine (may be NULL)
2291: Calling sequence of func:
2292: $ func (SNES snes,Vec x,void *ctx);
2294: . f - function vector
2295: - ctx - optional user-defined function context
2297: Level: intermediate
2299: .seealso: SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian()
2300: @*/
2301: PetscErrorCode SNESSetComputeInitialGuess(SNES snes,PetscErrorCode (*func)(SNES,Vec,void*),void *ctx)
2302: {
2305: if (func) snes->ops->computeinitialguess = func;
2306: if (ctx) snes->initialguessP = ctx;
2307: return(0);
2308: }
2310: /* --------------------------------------------------------------- */
2311: /*@C
2312: SNESGetRhs - Gets the vector for solving F(x) = rhs. If rhs is not set
2313: it assumes a zero right hand side.
2315: Logically Collective on SNES
2317: Input Parameter:
2318: . snes - the SNES context
2320: Output Parameter:
2321: . rhs - the right hand side vector or NULL if the right hand side vector is null
2323: Level: intermediate
2325: .seealso: SNESGetSolution(), SNESGetFunction(), SNESComputeFunction(), SNESSetJacobian(), SNESSetFunction()
2326: @*/
2327: PetscErrorCode SNESGetRhs(SNES snes,Vec *rhs)
2328: {
2332: *rhs = snes->vec_rhs;
2333: return(0);
2334: }
2336: /*@
2337: SNESComputeFunction - Calls the function that has been set with SNESSetFunction().
2339: Collective on SNES
2341: Input Parameters:
2342: + snes - the SNES context
2343: - x - input vector
2345: Output Parameter:
2346: . y - function vector, as set by SNESSetFunction()
2348: Notes:
2349: SNESComputeFunction() is typically used within nonlinear solvers
2350: implementations, so most users would not generally call this routine
2351: themselves.
2353: Level: developer
2355: .seealso: SNESSetFunction(), SNESGetFunction()
2356: @*/
2357: PetscErrorCode SNESComputeFunction(SNES snes,Vec x,Vec y)
2358: {
2360: DM dm;
2361: DMSNES sdm;
2369: VecValidValues(x,2,PETSC_TRUE);
2371: SNESGetDM(snes,&dm);
2372: DMGetDMSNES(dm,&sdm);
2373: if (sdm->ops->computefunction) {
2374: if (sdm->ops->computefunction != SNESObjectiveComputeFunctionDefaultFD) {
2375: PetscLogEventBegin(SNES_FunctionEval,snes,x,y,0);
2376: }
2377: VecLockReadPush(x);
2378: PetscStackPush("SNES user function");
2379: /* ensure domainerror is false prior to computefunction evaluation (may not have been reset) */
2380: snes->domainerror = PETSC_FALSE;
2381: (*sdm->ops->computefunction)(snes,x,y,sdm->functionctx);
2382: PetscStackPop;
2383: VecLockReadPop(x);
2384: if (sdm->ops->computefunction != SNESObjectiveComputeFunctionDefaultFD) {
2385: PetscLogEventEnd(SNES_FunctionEval,snes,x,y,0);
2386: }
2387: } else if (snes->vec_rhs) {
2388: MatMult(snes->jacobian, x, y);
2389: } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Must call SNESSetFunction() or SNESSetDM() before SNESComputeFunction(), likely called from SNESSolve().");
2390: if (snes->vec_rhs) {
2391: VecAXPY(y,-1.0,snes->vec_rhs);
2392: }
2393: snes->nfuncs++;
2394: /*
2395: domainerror might not be set on all processes; so we tag vector locally with Inf and the next inner product or norm will
2396: propagate the value to all processes
2397: */
2398: if (snes->domainerror) {
2399: VecSetInf(y);
2400: }
2401: return(0);
2402: }
2404: /*@
2405: SNESComputeNGS - Calls the Gauss-Seidel function that has been set with SNESSetNGS().
2407: Collective on SNES
2409: Input Parameters:
2410: + snes - the SNES context
2411: . x - input vector
2412: - b - rhs vector
2414: Output Parameter:
2415: . x - new solution vector
2417: Notes:
2418: SNESComputeNGS() is typically used within composed nonlinear solver
2419: implementations, so most users would not generally call this routine
2420: themselves.
2422: Level: developer
2424: .seealso: SNESSetNGS(), SNESComputeFunction()
2425: @*/
2426: PetscErrorCode SNESComputeNGS(SNES snes,Vec b,Vec x)
2427: {
2429: DM dm;
2430: DMSNES sdm;
2438: if (b) {VecValidValues(b,2,PETSC_TRUE);}
2439: PetscLogEventBegin(SNES_NGSEval,snes,x,b,0);
2440: SNESGetDM(snes,&dm);
2441: DMGetDMSNES(dm,&sdm);
2442: if (sdm->ops->computegs) {
2443: if (b) {VecLockReadPush(b);}
2444: PetscStackPush("SNES user NGS");
2445: (*sdm->ops->computegs)(snes,x,b,sdm->gsctx);
2446: PetscStackPop;
2447: if (b) {VecLockReadPop(b);}
2448: } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Must call SNESSetNGS() before SNESComputeNGS(), likely called from SNESSolve().");
2449: PetscLogEventEnd(SNES_NGSEval,snes,x,b,0);
2450: return(0);
2451: }
2453: PetscErrorCode SNESTestJacobian(SNES snes)
2454: {
2455: Mat A,B,C,D,jacobian;
2456: Vec x = snes->vec_sol,f = snes->vec_func;
2457: PetscErrorCode ierr;
2458: PetscReal nrm,gnorm;
2459: PetscReal threshold = 1.e-5;
2460: MatType mattype;
2461: PetscInt m,n,M,N;
2462: void *functx;
2463: PetscBool complete_print = PETSC_FALSE,threshold_print = PETSC_FALSE,test = PETSC_FALSE,flg,istranspose;
2464: PetscViewer viewer,mviewer;
2465: MPI_Comm comm;
2466: PetscInt tabs;
2467: static PetscBool directionsprinted = PETSC_FALSE;
2468: PetscViewerFormat format;
2471: PetscObjectOptionsBegin((PetscObject)snes);
2472: PetscOptionsName("-snes_test_jacobian","Compare hand-coded and finite difference Jacobians","None",&test);
2473: PetscOptionsReal("-snes_test_jacobian", "Threshold for element difference between hand-coded and finite difference being meaningful", "None", threshold, &threshold,NULL);
2474: PetscOptionsViewer("-snes_test_jacobian_view","View difference between hand-coded and finite difference Jacobians element entries","None",&mviewer,&format,&complete_print);
2475: if (!complete_print) {
2476: PetscOptionsDeprecated("-snes_test_jacobian_display","-snes_test_jacobian_view","3.13",NULL);
2477: PetscOptionsViewer("-snes_test_jacobian_display","Display difference between hand-coded and finite difference Jacobians","None",&mviewer,&format,&complete_print);
2478: }
2479: /* for compatibility with PETSc 3.9 and older. */
2480: PetscOptionsDeprecated("-snes_test_jacobian_display_threshold","-snes_test_jacobian","3.13","-snes_test_jacobian accepts an optional threshold (since v3.10)");
2481: PetscOptionsReal("-snes_test_jacobian_display_threshold", "Display difference between hand-coded and finite difference Jacobians which exceed input threshold", "None", threshold, &threshold, &threshold_print);
2482: PetscOptionsEnd();
2483: if (!test) return(0);
2485: PetscObjectGetComm((PetscObject)snes,&comm);
2486: PetscViewerASCIIGetStdout(comm,&viewer);
2487: PetscViewerASCIIGetTab(viewer, &tabs);
2488: PetscViewerASCIISetTab(viewer, ((PetscObject)snes)->tablevel);
2489: PetscViewerASCIIPrintf(viewer," ---------- Testing Jacobian -------------\n");
2490: if (!complete_print && !directionsprinted) {
2491: PetscViewerASCIIPrintf(viewer," Run with -snes_test_jacobian_view and optionally -snes_test_jacobian <threshold> to show difference\n");
2492: PetscViewerASCIIPrintf(viewer," of hand-coded and finite difference Jacobian entries greater than <threshold>.\n");
2493: }
2494: if (!directionsprinted) {
2495: PetscViewerASCIIPrintf(viewer," Testing hand-coded Jacobian, if (for double precision runs) ||J - Jfd||_F/||J||_F is\n");
2496: PetscViewerASCIIPrintf(viewer," O(1.e-8), the hand-coded Jacobian is probably correct.\n");
2497: directionsprinted = PETSC_TRUE;
2498: }
2499: if (complete_print) {
2500: PetscViewerPushFormat(mviewer,format);
2501: }
2503: PetscObjectTypeCompare((PetscObject)snes->jacobian,MATMFFD,&flg);
2504: if (!flg) jacobian = snes->jacobian;
2505: else jacobian = snes->jacobian_pre;
2507: if (!x) {
2508: MatCreateVecs(jacobian, &x, NULL);
2509: } else {
2510: PetscObjectReference((PetscObject) x);
2511: }
2512: if (!f) {
2513: VecDuplicate(x, &f);
2514: } else {
2515: PetscObjectReference((PetscObject) f);
2516: }
2517: /* evaluate the function at this point because SNESComputeJacobianDefault() assumes that the function has been evaluated and put into snes->vec_func */
2518: SNESComputeFunction(snes,x,f);
2519: VecDestroy(&f);
2520: PetscObjectTypeCompare((PetscObject)snes,SNESKSPTRANSPOSEONLY,&istranspose);
2521: while (jacobian) {
2522: Mat JT = NULL, Jsave = NULL;
2524: if (istranspose) {
2525: MatCreateTranspose(jacobian,&JT);
2526: Jsave = jacobian;
2527: jacobian = JT;
2528: }
2529: PetscObjectBaseTypeCompareAny((PetscObject)jacobian,&flg,MATSEQAIJ,MATMPIAIJ,MATSEQDENSE,MATMPIDENSE,MATSEQBAIJ,MATMPIBAIJ,MATSEQSBAIJ,MATMPISBAIJ,"");
2530: if (flg) {
2531: A = jacobian;
2532: PetscObjectReference((PetscObject)A);
2533: } else {
2534: MatComputeOperator(jacobian,MATAIJ,&A);
2535: }
2537: MatGetType(A,&mattype);
2538: MatGetSize(A,&M,&N);
2539: MatGetLocalSize(A,&m,&n);
2540: MatCreate(PetscObjectComm((PetscObject)A),&B);
2541: MatSetType(B,mattype);
2542: MatSetSizes(B,m,n,M,N);
2543: MatSetBlockSizesFromMats(B,A,A);
2544: MatSetUp(B);
2545: MatSetOption(B,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE);
2547: SNESGetFunction(snes,NULL,NULL,&functx);
2548: SNESComputeJacobianDefault(snes,x,B,B,functx);
2550: MatDuplicate(B,MAT_COPY_VALUES,&D);
2551: MatAYPX(D,-1.0,A,DIFFERENT_NONZERO_PATTERN);
2552: MatNorm(D,NORM_FROBENIUS,&nrm);
2553: MatNorm(A,NORM_FROBENIUS,&gnorm);
2554: MatDestroy(&D);
2555: if (!gnorm) gnorm = 1; /* just in case */
2556: PetscViewerASCIIPrintf(viewer," ||J - Jfd||_F/||J||_F = %g, ||J - Jfd||_F = %g\n",(double)(nrm/gnorm),(double)nrm);
2558: if (complete_print) {
2559: PetscViewerASCIIPrintf(viewer," Hand-coded Jacobian ----------\n");
2560: MatView(A,mviewer);
2561: PetscViewerASCIIPrintf(viewer," Finite difference Jacobian ----------\n");
2562: MatView(B,mviewer);
2563: }
2565: if (threshold_print || complete_print) {
2566: PetscInt Istart, Iend, *ccols, bncols, cncols, j, row;
2567: PetscScalar *cvals;
2568: const PetscInt *bcols;
2569: const PetscScalar *bvals;
2571: MatCreate(PetscObjectComm((PetscObject)A),&C);
2572: MatSetType(C,mattype);
2573: MatSetSizes(C,m,n,M,N);
2574: MatSetBlockSizesFromMats(C,A,A);
2575: MatSetUp(C);
2576: MatSetOption(C,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE);
2578: MatAYPX(B,-1.0,A,DIFFERENT_NONZERO_PATTERN);
2579: MatGetOwnershipRange(B,&Istart,&Iend);
2581: for (row = Istart; row < Iend; row++) {
2582: MatGetRow(B,row,&bncols,&bcols,&bvals);
2583: PetscMalloc2(bncols,&ccols,bncols,&cvals);
2584: for (j = 0, cncols = 0; j < bncols; j++) {
2585: if (PetscAbsScalar(bvals[j]) > threshold) {
2586: ccols[cncols] = bcols[j];
2587: cvals[cncols] = bvals[j];
2588: cncols += 1;
2589: }
2590: }
2591: if (cncols) {
2592: MatSetValues(C,1,&row,cncols,ccols,cvals,INSERT_VALUES);
2593: }
2594: MatRestoreRow(B,row,&bncols,&bcols,&bvals);
2595: PetscFree2(ccols,cvals);
2596: }
2597: MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);
2598: MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);
2599: PetscViewerASCIIPrintf(viewer," Hand-coded minus finite-difference Jacobian with tolerance %g ----------\n",(double)threshold);
2600: MatView(C,complete_print ? mviewer : viewer);
2601: MatDestroy(&C);
2602: }
2603: MatDestroy(&A);
2604: MatDestroy(&B);
2605: MatDestroy(&JT);
2606: if (Jsave) jacobian = Jsave;
2607: if (jacobian != snes->jacobian_pre) {
2608: jacobian = snes->jacobian_pre;
2609: PetscViewerASCIIPrintf(viewer," ---------- Testing Jacobian for preconditioner -------------\n");
2610: }
2611: else jacobian = NULL;
2612: }
2613: VecDestroy(&x);
2614: if (complete_print) {
2615: PetscViewerPopFormat(mviewer);
2616: }
2617: if (mviewer) { PetscViewerDestroy(&mviewer); }
2618: PetscViewerASCIISetTab(viewer,tabs);
2619: return(0);
2620: }
2622: /*@
2623: SNESComputeJacobian - Computes the Jacobian matrix that has been set with SNESSetJacobian().
2625: Collective on SNES
2627: Input Parameters:
2628: + snes - the SNES context
2629: - x - input vector
2631: Output Parameters:
2632: + A - Jacobian matrix
2633: - B - optional preconditioning matrix
2635: Options Database Keys:
2636: + -snes_lag_preconditioner <lag>
2637: . -snes_lag_jacobian <lag>
2638: . -snes_test_jacobian <optional threshold> - compare the user provided Jacobian with one compute via finite differences to check for errors. If a threshold is given, display only those entries whose difference is greater than the threshold.
2639: . -snes_test_jacobian_view - display the user provided Jacobian, the finite difference Jacobian and the difference between them to help users detect the location of errors in the user provided Jacobian
2640: . -snes_compare_explicit - Compare the computed Jacobian to the finite difference Jacobian and output the differences
2641: . -snes_compare_explicit_draw - Compare the computed Jacobian to the finite difference Jacobian and draw the result
2642: . -snes_compare_explicit_contour - Compare the computed Jacobian to the finite difference Jacobian and draw a contour plot with the result
2643: . -snes_compare_operator - Make the comparison options above use the operator instead of the preconditioning matrix
2644: . -snes_compare_coloring - Compute the finite difference Jacobian using coloring and display norms of difference
2645: . -snes_compare_coloring_display - Compute the finite differece Jacobian using coloring and display verbose differences
2646: . -snes_compare_coloring_threshold - Display only those matrix entries that differ by more than a given threshold
2647: . -snes_compare_coloring_threshold_atol - Absolute tolerance for difference in matrix entries to be displayed by -snes_compare_coloring_threshold
2648: . -snes_compare_coloring_threshold_rtol - Relative tolerance for difference in matrix entries to be displayed by -snes_compare_coloring_threshold
2649: . -snes_compare_coloring_draw - Compute the finite differece Jacobian using coloring and draw differences
2650: - -snes_compare_coloring_draw_contour - Compute the finite differece Jacobian using coloring and show contours of matrices and differences
2653: Notes:
2654: Most users should not need to explicitly call this routine, as it
2655: is used internally within the nonlinear solvers.
2657: Developer Notes:
2658: This has duplicative ways of checking the accuracy of the user provided Jacobian (see the options above). This is for historical reasons, the routine SNESTestJacobian() use to used
2659: for with the SNESType of test that has been removed.
2661: Level: developer
2663: .seealso: SNESSetJacobian(), KSPSetOperators(), MatStructure, SNESSetLagPreconditioner(), SNESSetLagJacobian()
2664: @*/
2665: PetscErrorCode SNESComputeJacobian(SNES snes,Vec X,Mat A,Mat B)
2666: {
2668: PetscBool flag;
2669: DM dm;
2670: DMSNES sdm;
2671: KSP ksp;
2677: VecValidValues(X,2,PETSC_TRUE);
2678: SNESGetDM(snes,&dm);
2679: DMGetDMSNES(dm,&sdm);
2681: if (!sdm->ops->computejacobian) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_USER,"Must call SNESSetJacobian(), DMSNESSetJacobian(), DMDASNESSetJacobianLocal(), etc");
2683: /* make sure that MatAssemblyBegin/End() is called on A matrix if it is matrix free */
2685: if (snes->lagjacobian == -2) {
2686: snes->lagjacobian = -1;
2688: PetscInfo(snes,"Recomputing Jacobian/preconditioner because lag is -2 (means compute Jacobian, but then never again) \n");
2689: } else if (snes->lagjacobian == -1) {
2690: PetscInfo(snes,"Reusing Jacobian/preconditioner because lag is -1\n");
2691: PetscObjectTypeCompare((PetscObject)A,MATMFFD,&flag);
2692: if (flag) {
2693: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
2694: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
2695: }
2696: return(0);
2697: } else if (snes->lagjacobian > 1 && (snes->iter + snes->jac_iter) % snes->lagjacobian) {
2698: PetscInfo2(snes,"Reusing Jacobian/preconditioner because lag is %D and SNES iteration is %D\n",snes->lagjacobian,snes->iter);
2699: PetscObjectTypeCompare((PetscObject)A,MATMFFD,&flag);
2700: if (flag) {
2701: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
2702: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
2703: }
2704: return(0);
2705: }
2706: if (snes->npc && snes->npcside== PC_LEFT) {
2707: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
2708: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
2709: return(0);
2710: }
2712: PetscLogEventBegin(SNES_JacobianEval,snes,X,A,B);
2713: VecLockReadPush(X);
2714: PetscStackPush("SNES user Jacobian function");
2715: (*sdm->ops->computejacobian)(snes,X,A,B,sdm->jacobianctx);
2716: PetscStackPop;
2717: VecLockReadPop(X);
2718: PetscLogEventEnd(SNES_JacobianEval,snes,X,A,B);
2720: /* attach latest linearization point to the preconditioning matrix */
2721: PetscObjectCompose((PetscObject)B,"__SNES_latest_X",(PetscObject)X);
2723: /* the next line ensures that snes->ksp exists */
2724: SNESGetKSP(snes,&ksp);
2725: if (snes->lagpreconditioner == -2) {
2726: PetscInfo(snes,"Rebuilding preconditioner exactly once since lag is -2\n");
2727: KSPSetReusePreconditioner(snes->ksp,PETSC_FALSE);
2728: snes->lagpreconditioner = -1;
2729: } else if (snes->lagpreconditioner == -1) {
2730: PetscInfo(snes,"Reusing preconditioner because lag is -1\n");
2731: KSPSetReusePreconditioner(snes->ksp,PETSC_TRUE);
2732: } else if (snes->lagpreconditioner > 1 && (snes->iter + snes->pre_iter) % snes->lagpreconditioner) {
2733: PetscInfo2(snes,"Reusing preconditioner because lag is %D and SNES iteration is %D\n",snes->lagpreconditioner,snes->iter);
2734: KSPSetReusePreconditioner(snes->ksp,PETSC_TRUE);
2735: } else {
2736: PetscInfo(snes,"Rebuilding preconditioner\n");
2737: KSPSetReusePreconditioner(snes->ksp,PETSC_FALSE);
2738: }
2740: SNESTestJacobian(snes);
2741: /* make sure user returned a correct Jacobian and preconditioner */
2744: {
2745: PetscBool flag = PETSC_FALSE,flag_draw = PETSC_FALSE,flag_contour = PETSC_FALSE,flag_operator = PETSC_FALSE;
2746: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject) snes)->options,((PetscObject)snes)->prefix,"-snes_compare_explicit",NULL,NULL,&flag);
2747: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject) snes)->options,((PetscObject)snes)->prefix,"-snes_compare_explicit_draw",NULL,NULL,&flag_draw);
2748: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject) snes)->options,((PetscObject)snes)->prefix,"-snes_compare_explicit_draw_contour",NULL,NULL,&flag_contour);
2749: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject) snes)->options,((PetscObject)snes)->prefix,"-snes_compare_operator",NULL,NULL,&flag_operator);
2750: if (flag || flag_draw || flag_contour) {
2751: Mat Bexp_mine = NULL,Bexp,FDexp;
2752: PetscViewer vdraw,vstdout;
2753: PetscBool flg;
2754: if (flag_operator) {
2755: MatComputeOperator(A,MATAIJ,&Bexp_mine);
2756: Bexp = Bexp_mine;
2757: } else {
2758: /* See if the preconditioning matrix can be viewed and added directly */
2759: PetscObjectBaseTypeCompareAny((PetscObject)B,&flg,MATSEQAIJ,MATMPIAIJ,MATSEQDENSE,MATMPIDENSE,MATSEQBAIJ,MATMPIBAIJ,MATSEQSBAIJ,MATMPIBAIJ,"");
2760: if (flg) Bexp = B;
2761: else {
2762: /* If the "preconditioning" matrix is itself MATSHELL or some other type without direct support */
2763: MatComputeOperator(B,MATAIJ,&Bexp_mine);
2764: Bexp = Bexp_mine;
2765: }
2766: }
2767: MatConvert(Bexp,MATSAME,MAT_INITIAL_MATRIX,&FDexp);
2768: SNESComputeJacobianDefault(snes,X,FDexp,FDexp,NULL);
2769: PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)snes),&vstdout);
2770: if (flag_draw || flag_contour) {
2771: PetscViewerDrawOpen(PetscObjectComm((PetscObject)snes),NULL,"Explicit Jacobians",PETSC_DECIDE,PETSC_DECIDE,300,300,&vdraw);
2772: if (flag_contour) {PetscViewerPushFormat(vdraw,PETSC_VIEWER_DRAW_CONTOUR);}
2773: } else vdraw = NULL;
2774: PetscViewerASCIIPrintf(vstdout,"Explicit %s\n",flag_operator ? "Jacobian" : "preconditioning Jacobian");
2775: if (flag) {MatView(Bexp,vstdout);}
2776: if (vdraw) {MatView(Bexp,vdraw);}
2777: PetscViewerASCIIPrintf(vstdout,"Finite difference Jacobian\n");
2778: if (flag) {MatView(FDexp,vstdout);}
2779: if (vdraw) {MatView(FDexp,vdraw);}
2780: MatAYPX(FDexp,-1.0,Bexp,SAME_NONZERO_PATTERN);
2781: PetscViewerASCIIPrintf(vstdout,"User-provided matrix minus finite difference Jacobian\n");
2782: if (flag) {MatView(FDexp,vstdout);}
2783: if (vdraw) { /* Always use contour for the difference */
2784: PetscViewerPushFormat(vdraw,PETSC_VIEWER_DRAW_CONTOUR);
2785: MatView(FDexp,vdraw);
2786: PetscViewerPopFormat(vdraw);
2787: }
2788: if (flag_contour) {PetscViewerPopFormat(vdraw);}
2789: PetscViewerDestroy(&vdraw);
2790: MatDestroy(&Bexp_mine);
2791: MatDestroy(&FDexp);
2792: }
2793: }
2794: {
2795: PetscBool flag = PETSC_FALSE,flag_display = PETSC_FALSE,flag_draw = PETSC_FALSE,flag_contour = PETSC_FALSE,flag_threshold = PETSC_FALSE;
2796: PetscReal threshold_atol = PETSC_SQRT_MACHINE_EPSILON,threshold_rtol = 10*PETSC_SQRT_MACHINE_EPSILON;
2797: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-snes_compare_coloring",NULL,NULL,&flag);
2798: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-snes_compare_coloring_display",NULL,NULL,&flag_display);
2799: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-snes_compare_coloring_draw",NULL,NULL,&flag_draw);
2800: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-snes_compare_coloring_draw_contour",NULL,NULL,&flag_contour);
2801: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-snes_compare_coloring_threshold",NULL,NULL,&flag_threshold);
2802: if (flag_threshold) {
2803: PetscOptionsGetReal(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-snes_compare_coloring_threshold_rtol",&threshold_rtol,NULL);
2804: PetscOptionsGetReal(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-snes_compare_coloring_threshold_atol",&threshold_atol,NULL);
2805: }
2806: if (flag || flag_display || flag_draw || flag_contour || flag_threshold) {
2807: Mat Bfd;
2808: PetscViewer vdraw,vstdout;
2809: MatColoring coloring;
2810: ISColoring iscoloring;
2811: MatFDColoring matfdcoloring;
2812: PetscErrorCode (*func)(SNES,Vec,Vec,void*);
2813: void *funcctx;
2814: PetscReal norm1,norm2,normmax;
2816: MatDuplicate(B,MAT_DO_NOT_COPY_VALUES,&Bfd);
2817: MatColoringCreate(Bfd,&coloring);
2818: MatColoringSetType(coloring,MATCOLORINGSL);
2819: MatColoringSetFromOptions(coloring);
2820: MatColoringApply(coloring,&iscoloring);
2821: MatColoringDestroy(&coloring);
2822: MatFDColoringCreate(Bfd,iscoloring,&matfdcoloring);
2823: MatFDColoringSetFromOptions(matfdcoloring);
2824: MatFDColoringSetUp(Bfd,iscoloring,matfdcoloring);
2825: ISColoringDestroy(&iscoloring);
2827: /* This method of getting the function is currently unreliable since it doesn't work for DM local functions. */
2828: SNESGetFunction(snes,NULL,&func,&funcctx);
2829: MatFDColoringSetFunction(matfdcoloring,(PetscErrorCode (*)(void))func,funcctx);
2830: PetscObjectSetOptionsPrefix((PetscObject)matfdcoloring,((PetscObject)snes)->prefix);
2831: PetscObjectAppendOptionsPrefix((PetscObject)matfdcoloring,"coloring_");
2832: MatFDColoringSetFromOptions(matfdcoloring);
2833: MatFDColoringApply(Bfd,matfdcoloring,X,snes);
2834: MatFDColoringDestroy(&matfdcoloring);
2836: PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)snes),&vstdout);
2837: if (flag_draw || flag_contour) {
2838: PetscViewerDrawOpen(PetscObjectComm((PetscObject)snes),NULL,"Colored Jacobians",PETSC_DECIDE,PETSC_DECIDE,300,300,&vdraw);
2839: if (flag_contour) {PetscViewerPushFormat(vdraw,PETSC_VIEWER_DRAW_CONTOUR);}
2840: } else vdraw = NULL;
2841: PetscViewerASCIIPrintf(vstdout,"Explicit preconditioning Jacobian\n");
2842: if (flag_display) {MatView(B,vstdout);}
2843: if (vdraw) {MatView(B,vdraw);}
2844: PetscViewerASCIIPrintf(vstdout,"Colored Finite difference Jacobian\n");
2845: if (flag_display) {MatView(Bfd,vstdout);}
2846: if (vdraw) {MatView(Bfd,vdraw);}
2847: MatAYPX(Bfd,-1.0,B,SAME_NONZERO_PATTERN);
2848: MatNorm(Bfd,NORM_1,&norm1);
2849: MatNorm(Bfd,NORM_FROBENIUS,&norm2);
2850: MatNorm(Bfd,NORM_MAX,&normmax);
2851: PetscViewerASCIIPrintf(vstdout,"User-provided matrix minus finite difference Jacobian, norm1=%g normFrob=%g normmax=%g\n",(double)norm1,(double)norm2,(double)normmax);
2852: if (flag_display) {MatView(Bfd,vstdout);}
2853: if (vdraw) { /* Always use contour for the difference */
2854: PetscViewerPushFormat(vdraw,PETSC_VIEWER_DRAW_CONTOUR);
2855: MatView(Bfd,vdraw);
2856: PetscViewerPopFormat(vdraw);
2857: }
2858: if (flag_contour) {PetscViewerPopFormat(vdraw);}
2860: if (flag_threshold) {
2861: PetscInt bs,rstart,rend,i;
2862: MatGetBlockSize(B,&bs);
2863: MatGetOwnershipRange(B,&rstart,&rend);
2864: for (i=rstart; i<rend; i++) {
2865: const PetscScalar *ba,*ca;
2866: const PetscInt *bj,*cj;
2867: PetscInt bn,cn,j,maxentrycol = -1,maxdiffcol = -1,maxrdiffcol = -1;
2868: PetscReal maxentry = 0,maxdiff = 0,maxrdiff = 0;
2869: MatGetRow(B,i,&bn,&bj,&ba);
2870: MatGetRow(Bfd,i,&cn,&cj,&ca);
2871: if (bn != cn) SETERRQ(((PetscObject)A)->comm,PETSC_ERR_PLIB,"Unexpected different nonzero pattern in -snes_compare_coloring_threshold");
2872: for (j=0; j<bn; j++) {
2873: PetscReal rdiff = PetscAbsScalar(ca[j]) / (threshold_atol + threshold_rtol*PetscAbsScalar(ba[j]));
2874: if (PetscAbsScalar(ba[j]) > PetscAbs(maxentry)) {
2875: maxentrycol = bj[j];
2876: maxentry = PetscRealPart(ba[j]);
2877: }
2878: if (PetscAbsScalar(ca[j]) > PetscAbs(maxdiff)) {
2879: maxdiffcol = bj[j];
2880: maxdiff = PetscRealPart(ca[j]);
2881: }
2882: if (rdiff > maxrdiff) {
2883: maxrdiffcol = bj[j];
2884: maxrdiff = rdiff;
2885: }
2886: }
2887: if (maxrdiff > 1) {
2888: 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);
2889: for (j=0; j<bn; j++) {
2890: PetscReal rdiff;
2891: rdiff = PetscAbsScalar(ca[j]) / (threshold_atol + threshold_rtol*PetscAbsScalar(ba[j]));
2892: if (rdiff > 1) {
2893: PetscViewerASCIIPrintf(vstdout," (%D,%g:%g)",bj[j],(double)PetscRealPart(ba[j]),(double)PetscRealPart(ca[j]));
2894: }
2895: }
2896: PetscViewerASCIIPrintf(vstdout,"\n",i,maxentry,maxdiff,maxrdiff);
2897: }
2898: MatRestoreRow(B,i,&bn,&bj,&ba);
2899: MatRestoreRow(Bfd,i,&cn,&cj,&ca);
2900: }
2901: }
2902: PetscViewerDestroy(&vdraw);
2903: MatDestroy(&Bfd);
2904: }
2905: }
2906: return(0);
2907: }
2909: /*MC
2910: SNESJacobianFunction - Function used to convey the nonlinear Jacobian of the function to be solved by SNES
2912: Synopsis:
2913: #include "petscsnes.h"
2914: PetscErrorCode SNESJacobianFunction(SNES snes,Vec x,Mat Amat,Mat Pmat,void *ctx);
2916: Collective on snes
2918: Input Parameters:
2919: + x - input vector, the Jacobian is to be computed at this value
2920: - ctx - [optional] user-defined Jacobian context
2922: Output Parameters:
2923: + Amat - the matrix that defines the (approximate) Jacobian
2924: - Pmat - the matrix to be used in constructing the preconditioner, usually the same as Amat.
2926: Level: intermediate
2928: .seealso: SNESSetFunction(), SNESGetFunction(), SNESSetJacobian(), SNESGetJacobian()
2929: M*/
2931: /*@C
2932: SNESSetJacobian - Sets the function to compute Jacobian as well as the
2933: location to store the matrix.
2935: Logically Collective on SNES
2937: Input Parameters:
2938: + snes - the SNES context
2939: . Amat - the matrix that defines the (approximate) Jacobian
2940: . Pmat - the matrix to be used in constructing the preconditioner, usually the same as Amat.
2941: . J - Jacobian evaluation routine (if NULL then SNES retains any previously set value), see SNESJacobianFunction for details
2942: - ctx - [optional] user-defined context for private data for the
2943: Jacobian evaluation routine (may be NULL) (if NULL then SNES retains any previously set value)
2945: Notes:
2946: If the Amat matrix and Pmat matrix are different you must call MatAssemblyBegin/End() on
2947: each matrix.
2949: If you know the operator Amat has a null space you can use MatSetNullSpace() and MatSetTransposeNullSpace() to supply the null
2950: space to Amat and the KSP solvers will automatically use that null space as needed during the solution process.
2952: If using SNESComputeJacobianDefaultColor() to assemble a Jacobian, the ctx argument
2953: must be a MatFDColoring.
2955: Other defect-correction schemes can be used by computing a different matrix in place of the Jacobian. One common
2956: example is to use the "Picard linearization" which only differentiates through the highest order parts of each term.
2958: Level: beginner
2960: .seealso: KSPSetOperators(), SNESSetFunction(), MatMFFDComputeJacobian(), SNESComputeJacobianDefaultColor(), MatStructure, J,
2961: SNESSetPicard(), SNESJacobianFunction
2962: @*/
2963: PetscErrorCode SNESSetJacobian(SNES snes,Mat Amat,Mat Pmat,PetscErrorCode (*J)(SNES,Vec,Mat,Mat,void*),void *ctx)
2964: {
2966: DM dm;
2974: SNESGetDM(snes,&dm);
2975: DMSNESSetJacobian(dm,J,ctx);
2976: if (Amat) {
2977: PetscObjectReference((PetscObject)Amat);
2978: MatDestroy(&snes->jacobian);
2980: snes->jacobian = Amat;
2981: }
2982: if (Pmat) {
2983: PetscObjectReference((PetscObject)Pmat);
2984: MatDestroy(&snes->jacobian_pre);
2986: snes->jacobian_pre = Pmat;
2987: }
2988: return(0);
2989: }
2991: /*@C
2992: SNESGetJacobian - Returns the Jacobian matrix and optionally the user
2993: provided context for evaluating the Jacobian.
2995: Not Collective, but Mat object will be parallel if SNES object is
2997: Input Parameter:
2998: . snes - the nonlinear solver context
3000: Output Parameters:
3001: + Amat - location to stash (approximate) Jacobian matrix (or NULL)
3002: . Pmat - location to stash matrix used to compute the preconditioner (or NULL)
3003: . J - location to put Jacobian function (or NULL), see SNESJacobianFunction for details on its calling sequence
3004: - ctx - location to stash Jacobian ctx (or NULL)
3006: Level: advanced
3008: .seealso: SNESSetJacobian(), SNESComputeJacobian(), SNESJacobianFunction, SNESGetFunction()
3009: @*/
3010: PetscErrorCode SNESGetJacobian(SNES snes,Mat *Amat,Mat *Pmat,PetscErrorCode (**J)(SNES,Vec,Mat,Mat,void*),void **ctx)
3011: {
3013: DM dm;
3014: DMSNES sdm;
3018: if (Amat) *Amat = snes->jacobian;
3019: if (Pmat) *Pmat = snes->jacobian_pre;
3020: SNESGetDM(snes,&dm);
3021: DMGetDMSNES(dm,&sdm);
3022: if (J) *J = sdm->ops->computejacobian;
3023: if (ctx) *ctx = sdm->jacobianctx;
3024: return(0);
3025: }
3027: static PetscErrorCode SNESSetDefaultComputeJacobian(SNES snes)
3028: {
3030: DM dm;
3031: DMSNES sdm;
3034: SNESGetDM(snes,&dm);
3035: DMGetDMSNES(dm,&sdm);
3036: if (!sdm->ops->computejacobian && snes->jacobian_pre) {
3037: DM dm;
3038: PetscBool isdense,ismf;
3040: SNESGetDM(snes,&dm);
3041: PetscObjectTypeCompareAny((PetscObject)snes->jacobian_pre,&isdense,MATSEQDENSE,MATMPIDENSE,MATDENSE,NULL);
3042: PetscObjectTypeCompareAny((PetscObject)snes->jacobian_pre,&ismf,MATMFFD,MATSHELL,NULL);
3043: if (isdense) {
3044: DMSNESSetJacobian(dm,SNESComputeJacobianDefault,NULL);
3045: } else if (!ismf) {
3046: DMSNESSetJacobian(dm,SNESComputeJacobianDefaultColor,NULL);
3047: }
3048: }
3049: return(0);
3050: }
3052: /*@
3053: SNESSetUp - Sets up the internal data structures for the later use
3054: of a nonlinear solver.
3056: Collective on SNES
3058: Input Parameters:
3059: . snes - the SNES context
3061: Notes:
3062: For basic use of the SNES solvers the user need not explicitly call
3063: SNESSetUp(), since these actions will automatically occur during
3064: the call to SNESSolve(). However, if one wishes to control this
3065: phase separately, SNESSetUp() should be called after SNESCreate()
3066: and optional routines of the form SNESSetXXX(), but before SNESSolve().
3068: Level: advanced
3070: .seealso: SNESCreate(), SNESSolve(), SNESDestroy()
3071: @*/
3072: PetscErrorCode SNESSetUp(SNES snes)
3073: {
3075: DM dm;
3076: DMSNES sdm;
3077: SNESLineSearch linesearch, pclinesearch;
3078: void *lsprectx,*lspostctx;
3079: PetscErrorCode (*precheck)(SNESLineSearch,Vec,Vec,PetscBool*,void*);
3080: PetscErrorCode (*postcheck)(SNESLineSearch,Vec,Vec,Vec,PetscBool*,PetscBool*,void*);
3081: PetscErrorCode (*func)(SNES,Vec,Vec,void*);
3082: Vec f,fpc;
3083: void *funcctx;
3084: PetscErrorCode (*jac)(SNES,Vec,Mat,Mat,void*);
3085: void *jacctx,*appctx;
3086: Mat j,jpre;
3090: if (snes->setupcalled) return(0);
3091: PetscLogEventBegin(SNES_Setup,snes,0,0,0);
3093: if (!((PetscObject)snes)->type_name) {
3094: SNESSetType(snes,SNESNEWTONLS);
3095: }
3097: SNESGetFunction(snes,&snes->vec_func,NULL,NULL);
3099: SNESGetDM(snes,&dm);
3100: DMGetDMSNES(dm,&sdm);
3101: if (!sdm->ops->computefunction) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_ARG_WRONGSTATE,"Function never provided to SNES object");
3102: SNESSetDefaultComputeJacobian(snes);
3104: if (!snes->vec_func) {
3105: DMCreateGlobalVector(dm,&snes->vec_func);
3106: }
3108: if (!snes->ksp) {
3109: SNESGetKSP(snes, &snes->ksp);
3110: }
3112: if (snes->linesearch) {
3113: SNESGetLineSearch(snes, &snes->linesearch);
3114: SNESLineSearchSetFunction(snes->linesearch,SNESComputeFunction);
3115: }
3117: if (snes->npc && (snes->npcside== PC_LEFT)) {
3118: snes->mf = PETSC_TRUE;
3119: snes->mf_operator = PETSC_FALSE;
3120: }
3122: if (snes->npc) {
3123: /* copy the DM over */
3124: SNESGetDM(snes,&dm);
3125: SNESSetDM(snes->npc,dm);
3127: SNESGetFunction(snes,&f,&func,&funcctx);
3128: VecDuplicate(f,&fpc);
3129: SNESSetFunction(snes->npc,fpc,func,funcctx);
3130: SNESGetJacobian(snes,&j,&jpre,&jac,&jacctx);
3131: SNESSetJacobian(snes->npc,j,jpre,jac,jacctx);
3132: SNESGetApplicationContext(snes,&appctx);
3133: SNESSetApplicationContext(snes->npc,appctx);
3134: VecDestroy(&fpc);
3136: /* copy the function pointers over */
3137: PetscObjectCopyFortranFunctionPointers((PetscObject)snes,(PetscObject)snes->npc);
3139: /* default to 1 iteration */
3140: SNESSetTolerances(snes->npc,0.0,0.0,0.0,1,snes->npc->max_funcs);
3141: if (snes->npcside==PC_RIGHT) {
3142: SNESSetNormSchedule(snes->npc,SNES_NORM_FINAL_ONLY);
3143: } else {
3144: SNESSetNormSchedule(snes->npc,SNES_NORM_NONE);
3145: }
3146: SNESSetFromOptions(snes->npc);
3148: /* copy the line search context over */
3149: if (snes->linesearch && snes->npc->linesearch) {
3150: SNESGetLineSearch(snes,&linesearch);
3151: SNESGetLineSearch(snes->npc,&pclinesearch);
3152: SNESLineSearchGetPreCheck(linesearch,&precheck,&lsprectx);
3153: SNESLineSearchGetPostCheck(linesearch,&postcheck,&lspostctx);
3154: SNESLineSearchSetPreCheck(pclinesearch,precheck,lsprectx);
3155: SNESLineSearchSetPostCheck(pclinesearch,postcheck,lspostctx);
3156: PetscObjectCopyFortranFunctionPointers((PetscObject)linesearch, (PetscObject)pclinesearch);
3157: }
3158: }
3159: if (snes->mf) {
3160: SNESSetUpMatrixFree_Private(snes, snes->mf_operator, snes->mf_version);
3161: }
3162: if (snes->ops->usercompute && !snes->user) {
3163: (*snes->ops->usercompute)(snes,(void**)&snes->user);
3164: }
3166: snes->jac_iter = 0;
3167: snes->pre_iter = 0;
3169: if (snes->ops->setup) {
3170: (*snes->ops->setup)(snes);
3171: }
3173: SNESSetDefaultComputeJacobian(snes);
3175: if (snes->npc && (snes->npcside== PC_LEFT)) {
3176: if (snes->functype == SNES_FUNCTION_PRECONDITIONED) {
3177: if (snes->linesearch){
3178: SNESGetLineSearch(snes,&linesearch);
3179: SNESLineSearchSetFunction(linesearch,SNESComputeFunctionDefaultNPC);
3180: }
3181: }
3182: }
3183: PetscLogEventEnd(SNES_Setup,snes,0,0,0);
3184: snes->setupcalled = PETSC_TRUE;
3185: return(0);
3186: }
3188: /*@
3189: SNESReset - Resets a SNES context to the snessetupcalled = 0 state and removes any allocated Vecs and Mats
3191: Collective on SNES
3193: Input Parameter:
3194: . snes - iterative context obtained from SNESCreate()
3196: Level: intermediate
3198: Notes:
3199: Also calls the application context destroy routine set with SNESSetComputeApplicationContext()
3201: .seealso: SNESCreate(), SNESSetUp(), SNESSolve()
3202: @*/
3203: PetscErrorCode SNESReset(SNES snes)
3204: {
3209: if (snes->ops->userdestroy && snes->user) {
3210: (*snes->ops->userdestroy)((void**)&snes->user);
3211: snes->user = NULL;
3212: }
3213: if (snes->npc) {
3214: SNESReset(snes->npc);
3215: }
3217: if (snes->ops->reset) {
3218: (*snes->ops->reset)(snes);
3219: }
3220: if (snes->ksp) {
3221: KSPReset(snes->ksp);
3222: }
3224: if (snes->linesearch) {
3225: SNESLineSearchReset(snes->linesearch);
3226: }
3228: VecDestroy(&snes->vec_rhs);
3229: VecDestroy(&snes->vec_sol);
3230: VecDestroy(&snes->vec_sol_update);
3231: VecDestroy(&snes->vec_func);
3232: MatDestroy(&snes->jacobian);
3233: MatDestroy(&snes->jacobian_pre);
3234: VecDestroyVecs(snes->nwork,&snes->work);
3235: VecDestroyVecs(snes->nvwork,&snes->vwork);
3237: snes->alwayscomputesfinalresidual = PETSC_FALSE;
3239: snes->nwork = snes->nvwork = 0;
3240: snes->setupcalled = PETSC_FALSE;
3241: return(0);
3242: }
3244: /*@
3245: SNESDestroy - Destroys the nonlinear solver context that was created
3246: with SNESCreate().
3248: Collective on SNES
3250: Input Parameter:
3251: . snes - the SNES context
3253: Level: beginner
3255: .seealso: SNESCreate(), SNESSolve()
3256: @*/
3257: PetscErrorCode SNESDestroy(SNES *snes)
3258: {
3262: if (!*snes) return(0);
3264: if (--((PetscObject)(*snes))->refct > 0) {*snes = NULL; return(0);}
3266: SNESReset((*snes));
3267: SNESDestroy(&(*snes)->npc);
3269: /* if memory was published with SAWs then destroy it */
3270: PetscObjectSAWsViewOff((PetscObject)*snes);
3271: if ((*snes)->ops->destroy) {(*((*snes))->ops->destroy)((*snes));}
3273: if ((*snes)->dm) {DMCoarsenHookRemove((*snes)->dm,DMCoarsenHook_SNESVecSol,DMRestrictHook_SNESVecSol,*snes);}
3274: DMDestroy(&(*snes)->dm);
3275: KSPDestroy(&(*snes)->ksp);
3276: SNESLineSearchDestroy(&(*snes)->linesearch);
3278: PetscFree((*snes)->kspconvctx);
3279: if ((*snes)->ops->convergeddestroy) {
3280: (*(*snes)->ops->convergeddestroy)((*snes)->cnvP);
3281: }
3282: if ((*snes)->conv_hist_alloc) {
3283: PetscFree2((*snes)->conv_hist,(*snes)->conv_hist_its);
3284: }
3285: SNESMonitorCancel((*snes));
3286: PetscHeaderDestroy(snes);
3287: return(0);
3288: }
3290: /* ----------- Routines to set solver parameters ---------- */
3292: /*@
3293: SNESSetLagPreconditioner - Determines when the preconditioner is rebuilt in the nonlinear solve.
3295: Logically Collective on SNES
3297: Input Parameters:
3298: + snes - the SNES context
3299: - lag - -1 indicates NEVER rebuild, 1 means rebuild every time the Jacobian is computed within a single nonlinear solve, 2 means every second time
3300: the Jacobian is built etc. -2 indicates rebuild preconditioner at next chance but then never rebuild after that
3302: Options Database Keys:
3303: + -snes_lag_jacobian_persists <true,false> - sets the persistence
3304: . -snes_lag_jacobian <-2,1,2,...> - sets the lag
3305: . -snes_lag_preconditioner_persists <true,false> - sets the persistence
3306: - -snes_lag_preconditioner <-2,1,2,...> - sets the lag
3308: Notes:
3309: The default is 1
3310: The preconditioner is ALWAYS built in the first iteration of a nonlinear solve unless lag is -1 or SNESSetLagPreconditionerPersists() was called
3311: If -1 is used before the very first nonlinear solve the preconditioner is still built because there is no previous preconditioner to use
3313: Level: intermediate
3315: .seealso: SNESSetTrustRegionTolerance(), SNESGetLagPreconditioner(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESSetLagPreconditionerPersists(),
3316: SNESSetLagJacobianPersists()
3318: @*/
3319: PetscErrorCode SNESSetLagPreconditioner(SNES snes,PetscInt lag)
3320: {
3323: if (lag < -2) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Lag must be -2, -1, 1 or greater");
3324: if (!lag) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Lag cannot be 0");
3326: snes->lagpreconditioner = lag;
3327: return(0);
3328: }
3330: /*@
3331: SNESSetGridSequence - sets the number of steps of grid sequencing that SNES does
3333: Logically Collective on SNES
3335: Input Parameters:
3336: + snes - the SNES context
3337: - steps - the number of refinements to do, defaults to 0
3339: Options Database Keys:
3340: . -snes_grid_sequence <steps>
3342: Level: intermediate
3344: Notes:
3345: Use SNESGetSolution() to extract the fine grid solution after grid sequencing.
3347: .seealso: SNESSetTrustRegionTolerance(), SNESGetLagPreconditioner(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESGetGridSequence()
3349: @*/
3350: PetscErrorCode SNESSetGridSequence(SNES snes,PetscInt steps)
3351: {
3355: snes->gridsequence = steps;
3356: return(0);
3357: }
3359: /*@
3360: SNESGetGridSequence - gets the number of steps of grid sequencing that SNES does
3362: Logically Collective on SNES
3364: Input Parameter:
3365: . snes - the SNES context
3367: Output Parameter:
3368: . steps - the number of refinements to do, defaults to 0
3370: Options Database Keys:
3371: . -snes_grid_sequence <steps>
3373: Level: intermediate
3375: Notes:
3376: Use SNESGetSolution() to extract the fine grid solution after grid sequencing.
3378: .seealso: SNESSetTrustRegionTolerance(), SNESGetLagPreconditioner(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESSetGridSequence()
3380: @*/
3381: PetscErrorCode SNESGetGridSequence(SNES snes,PetscInt *steps)
3382: {
3385: *steps = snes->gridsequence;
3386: return(0);
3387: }
3389: /*@
3390: SNESGetLagPreconditioner - Indicates how often the preconditioner is rebuilt
3392: Not Collective
3394: Input Parameter:
3395: . snes - the SNES context
3397: Output Parameter:
3398: . lag - -1 indicates NEVER rebuild, 1 means rebuild every time the Jacobian is computed within a single nonlinear solve, 2 means every second time
3399: the Jacobian is built etc. -2 indicates rebuild preconditioner at next chance but then never rebuild after that
3401: Options Database Keys:
3402: + -snes_lag_jacobian_persists <true,false> - sets the persistence
3403: . -snes_lag_jacobian <-2,1,2,...> - sets the lag
3404: . -snes_lag_preconditioner_persists <true,false> - sets the persistence
3405: - -snes_lag_preconditioner <-2,1,2,...> - sets the lag
3407: Notes:
3408: The default is 1
3409: The preconditioner is ALWAYS built in the first iteration of a nonlinear solve unless lag is -1
3411: Level: intermediate
3413: .seealso: SNESSetTrustRegionTolerance(), SNESSetLagPreconditioner(), SNESSetLagJacobianPersists(), SNESSetLagPreconditionerPersists()
3415: @*/
3416: PetscErrorCode SNESGetLagPreconditioner(SNES snes,PetscInt *lag)
3417: {
3420: *lag = snes->lagpreconditioner;
3421: return(0);
3422: }
3424: /*@
3425: SNESSetLagJacobian - Determines when the Jacobian is rebuilt in the nonlinear solve. See SNESSetLagPreconditioner() for determining how
3426: often the preconditioner is rebuilt.
3428: Logically Collective on SNES
3430: Input Parameters:
3431: + snes - the SNES context
3432: - lag - -1 indicates NEVER rebuild, 1 means rebuild every time the Jacobian is computed within a single nonlinear solve, 2 means every second time
3433: the Jacobian is built etc. -2 means rebuild at next chance but then never again
3435: Options Database Keys:
3436: + -snes_lag_jacobian_persists <true,false> - sets the persistence
3437: . -snes_lag_jacobian <-2,1,2,...> - sets the lag
3438: . -snes_lag_preconditioner_persists <true,false> - sets the persistence
3439: - -snes_lag_preconditioner <-2,1,2,...> - sets the lag.
3441: Notes:
3442: The default is 1
3443: The Jacobian is ALWAYS built in the first iteration of a nonlinear solve unless lag is -1
3444: 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
3445: at the next Newton step but never again (unless it is reset to another value)
3447: Level: intermediate
3449: .seealso: SNESSetTrustRegionTolerance(), SNESGetLagPreconditioner(), SNESSetLagPreconditioner(), SNESGetLagJacobianPersists(), SNESSetLagPreconditionerPersists()
3451: @*/
3452: PetscErrorCode SNESSetLagJacobian(SNES snes,PetscInt lag)
3453: {
3456: if (lag < -2) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Lag must be -2, -1, 1 or greater");
3457: if (!lag) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Lag cannot be 0");
3459: snes->lagjacobian = lag;
3460: return(0);
3461: }
3463: /*@
3464: SNESGetLagJacobian - Indicates how often the Jacobian is rebuilt. See SNESGetLagPreconditioner() to determine when the preconditioner is rebuilt
3466: Not Collective
3468: Input Parameter:
3469: . snes - the SNES context
3471: Output Parameter:
3472: . lag - -1 indicates NEVER rebuild, 1 means rebuild every time the Jacobian is computed within a single nonlinear solve, 2 means every second time
3473: the Jacobian is built etc.
3475: Notes:
3476: The default is 1
3477: The jacobian is ALWAYS built in the first iteration of a nonlinear solve unless lag is -1 or SNESSetLagJacobianPersists() was called.
3479: Level: intermediate
3481: .seealso: SNESSetTrustRegionTolerance(), SNESSetLagJacobian(), SNESSetLagPreconditioner(), SNESGetLagPreconditioner(), SNESSetLagJacobianPersists(), SNESSetLagPreconditionerPersists()
3483: @*/
3484: PetscErrorCode SNESGetLagJacobian(SNES snes,PetscInt *lag)
3485: {
3488: *lag = snes->lagjacobian;
3489: return(0);
3490: }
3492: /*@
3493: SNESSetLagJacobianPersists - Set whether or not the Jacobian lagging persists through multiple solves
3495: Logically collective on SNES
3497: Input Parameter:
3498: + snes - the SNES context
3499: - flg - jacobian lagging persists if true
3501: Options Database Keys:
3502: + -snes_lag_jacobian_persists <true,false> - sets the persistence
3503: . -snes_lag_jacobian <-2,1,2,...> - sets the lag
3504: . -snes_lag_preconditioner_persists <true,false> - sets the persistence
3505: - -snes_lag_preconditioner <-2,1,2,...> - sets the lag
3508: Notes:
3509: This is useful both for nonlinear preconditioning, where it's appropriate to have the Jacobian be stale by
3510: several solves, and for implicit time-stepping, where Jacobian lagging in the inner nonlinear solve over several
3511: timesteps may present huge efficiency gains.
3513: Level: developer
3515: .seealso: SNESSetLagPreconditionerPersists(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESGetNPC(), SNESSetLagJacobianPersists()
3517: @*/
3518: PetscErrorCode SNESSetLagJacobianPersists(SNES snes,PetscBool flg)
3519: {
3523: snes->lagjac_persist = flg;
3524: return(0);
3525: }
3527: /*@
3528: SNESSetLagPreconditionerPersists - Set whether or not the preconditioner lagging persists through multiple solves
3530: Logically Collective on SNES
3532: Input Parameter:
3533: + snes - the SNES context
3534: - flg - preconditioner lagging persists if true
3536: Options Database Keys:
3537: + -snes_lag_jacobian_persists <true,false> - sets the persistence
3538: . -snes_lag_jacobian <-2,1,2,...> - sets the lag
3539: . -snes_lag_preconditioner_persists <true,false> - sets the persistence
3540: - -snes_lag_preconditioner <-2,1,2,...> - sets the lag
3542: Notes:
3543: This is useful both for nonlinear preconditioning, where it's appropriate to have the preconditioner be stale
3544: by several solves, and for implicit time-stepping, where preconditioner lagging in the inner nonlinear solve over
3545: several timesteps may present huge efficiency gains.
3547: Level: developer
3549: .seealso: SNESSetLagJacobianPersists(), SNESSetLagJacobian(), SNESGetLagJacobian(), SNESGetNPC(), SNESSetLagPreconditioner()
3551: @*/
3552: PetscErrorCode SNESSetLagPreconditionerPersists(SNES snes,PetscBool flg)
3553: {
3557: snes->lagpre_persist = flg;
3558: return(0);
3559: }
3561: /*@
3562: SNESSetForceIteration - force SNESSolve() to take at least one iteration regardless of the initial residual norm
3564: Logically Collective on SNES
3566: Input Parameters:
3567: + snes - the SNES context
3568: - force - PETSC_TRUE require at least one iteration
3570: Options Database Keys:
3571: . -snes_force_iteration <force> - Sets forcing an iteration
3573: Notes:
3574: This is used sometimes with TS to prevent TS from detecting a false steady state solution
3576: Level: intermediate
3578: .seealso: SNESSetTrustRegionTolerance(), SNESSetDivergenceTolerance()
3579: @*/
3580: PetscErrorCode SNESSetForceIteration(SNES snes,PetscBool force)
3581: {
3584: snes->forceiteration = force;
3585: return(0);
3586: }
3588: /*@
3589: SNESGetForceIteration - Whether or not to force SNESSolve() take at least one iteration regardless of the initial residual norm
3591: Logically Collective on SNES
3593: Input Parameters:
3594: . snes - the SNES context
3596: Output Parameter:
3597: . force - PETSC_TRUE requires at least one iteration.
3599: Level: intermediate
3601: .seealso: SNESSetForceIteration(), SNESSetTrustRegionTolerance(), SNESSetDivergenceTolerance()
3602: @*/
3603: PetscErrorCode SNESGetForceIteration(SNES snes,PetscBool *force)
3604: {
3607: *force = snes->forceiteration;
3608: return(0);
3609: }
3611: /*@
3612: SNESSetTolerances - Sets various parameters used in convergence tests.
3614: Logically Collective on SNES
3616: Input Parameters:
3617: + snes - the SNES context
3618: . abstol - absolute convergence tolerance
3619: . rtol - relative convergence tolerance
3620: . stol - convergence tolerance in terms of the norm of the change in the solution between steps, || delta x || < stol*|| x ||
3621: . maxit - maximum number of iterations
3622: - maxf - maximum number of function evaluations (-1 indicates no limit)
3624: Options Database Keys:
3625: + -snes_atol <abstol> - Sets abstol
3626: . -snes_rtol <rtol> - Sets rtol
3627: . -snes_stol <stol> - Sets stol
3628: . -snes_max_it <maxit> - Sets maxit
3629: - -snes_max_funcs <maxf> - Sets maxf
3631: Notes:
3632: The default maximum number of iterations is 50.
3633: The default maximum number of function evaluations is 1000.
3635: Level: intermediate
3637: .seealso: SNESSetTrustRegionTolerance(), SNESSetDivergenceTolerance(), SNESSetForceIteration()
3638: @*/
3639: PetscErrorCode SNESSetTolerances(SNES snes,PetscReal abstol,PetscReal rtol,PetscReal stol,PetscInt maxit,PetscInt maxf)
3640: {
3649: if (abstol != PETSC_DEFAULT) {
3650: if (abstol < 0.0) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Absolute tolerance %g must be non-negative",(double)abstol);
3651: snes->abstol = abstol;
3652: }
3653: if (rtol != PETSC_DEFAULT) {
3654: 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);
3655: snes->rtol = rtol;
3656: }
3657: if (stol != PETSC_DEFAULT) {
3658: if (stol < 0.0) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Step tolerance %g must be non-negative",(double)stol);
3659: snes->stol = stol;
3660: }
3661: if (maxit != PETSC_DEFAULT) {
3662: if (maxit < 0) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Maximum number of iterations %D must be non-negative",maxit);
3663: snes->max_its = maxit;
3664: }
3665: if (maxf != PETSC_DEFAULT) {
3666: if (maxf < -1) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_OUTOFRANGE,"Maximum number of function evaluations %D must be -1 or nonnegative",maxf);
3667: snes->max_funcs = maxf;
3668: }
3669: snes->tolerancesset = PETSC_TRUE;
3670: return(0);
3671: }
3673: /*@
3674: SNESSetDivergenceTolerance - Sets the divergence tolerance used for the SNES divergence test.
3676: Logically Collective on SNES
3678: Input Parameters:
3679: + snes - the SNES context
3680: - divtol - the divergence tolerance. Use -1 to deactivate the test.
3682: Options Database Keys:
3683: . -snes_divergence_tolerance <divtol> - Sets divtol
3685: Notes:
3686: The default divergence tolerance is 1e4.
3688: Level: intermediate
3690: .seealso: SNESSetTolerances(), SNESGetDivergenceTolerance
3691: @*/
3692: PetscErrorCode SNESSetDivergenceTolerance(SNES snes,PetscReal divtol)
3693: {
3698: if (divtol != PETSC_DEFAULT) {
3699: snes->divtol = divtol;
3700: }
3701: else {
3702: snes->divtol = 1.0e4;
3703: }
3704: return(0);
3705: }
3707: /*@
3708: SNESGetTolerances - Gets various parameters used in convergence tests.
3710: Not Collective
3712: Input Parameters:
3713: + snes - the SNES context
3714: . atol - absolute convergence tolerance
3715: . rtol - relative convergence tolerance
3716: . stol - convergence tolerance in terms of the norm
3717: of the change in the solution between steps
3718: . maxit - maximum number of iterations
3719: - maxf - maximum number of function evaluations
3721: Notes:
3722: The user can specify NULL for any parameter that is not needed.
3724: Level: intermediate
3726: .seealso: SNESSetTolerances()
3727: @*/
3728: PetscErrorCode SNESGetTolerances(SNES snes,PetscReal *atol,PetscReal *rtol,PetscReal *stol,PetscInt *maxit,PetscInt *maxf)
3729: {
3732: if (atol) *atol = snes->abstol;
3733: if (rtol) *rtol = snes->rtol;
3734: if (stol) *stol = snes->stol;
3735: if (maxit) *maxit = snes->max_its;
3736: if (maxf) *maxf = snes->max_funcs;
3737: return(0);
3738: }
3740: /*@
3741: SNESGetDivergenceTolerance - Gets divergence tolerance used in divergence test.
3743: Not Collective
3745: Input Parameters:
3746: + snes - the SNES context
3747: - divtol - divergence tolerance
3749: Level: intermediate
3751: .seealso: SNESSetDivergenceTolerance()
3752: @*/
3753: PetscErrorCode SNESGetDivergenceTolerance(SNES snes,PetscReal *divtol)
3754: {
3757: if (divtol) *divtol = snes->divtol;
3758: return(0);
3759: }
3761: /*@
3762: SNESSetTrustRegionTolerance - Sets the trust region parameter tolerance.
3764: Logically Collective on SNES
3766: Input Parameters:
3767: + snes - the SNES context
3768: - tol - tolerance
3770: Options Database Key:
3771: . -snes_trtol <tol> - Sets tol
3773: Level: intermediate
3775: .seealso: SNESSetTolerances()
3776: @*/
3777: PetscErrorCode SNESSetTrustRegionTolerance(SNES snes,PetscReal tol)
3778: {
3782: snes->deltatol = tol;
3783: return(0);
3784: }
3786: /*
3787: Duplicate the lg monitors for SNES from KSP; for some reason with
3788: dynamic libraries things don't work under Sun4 if we just use
3789: macros instead of functions
3790: */
3791: PetscErrorCode SNESMonitorLGResidualNorm(SNES snes,PetscInt it,PetscReal norm,void *ctx)
3792: {
3797: KSPMonitorLGResidualNorm((KSP)snes,it,norm,ctx);
3798: return(0);
3799: }
3801: PetscErrorCode SNESMonitorLGCreate(MPI_Comm comm,const char host[],const char label[],int x,int y,int m,int n,PetscDrawLG *lgctx)
3802: {
3806: KSPMonitorLGResidualNormCreate(comm,host,label,x,y,m,n,lgctx);
3807: return(0);
3808: }
3810: PETSC_INTERN PetscErrorCode SNESMonitorRange_Private(SNES,PetscInt,PetscReal*);
3812: PetscErrorCode SNESMonitorLGRange(SNES snes,PetscInt n,PetscReal rnorm,void *monctx)
3813: {
3814: PetscDrawLG lg;
3815: PetscErrorCode ierr;
3816: PetscReal x,y,per;
3817: PetscViewer v = (PetscViewer)monctx;
3818: static PetscReal prev; /* should be in the context */
3819: PetscDraw draw;
3823: PetscViewerDrawGetDrawLG(v,0,&lg);
3824: if (!n) {PetscDrawLGReset(lg);}
3825: PetscDrawLGGetDraw(lg,&draw);
3826: PetscDrawSetTitle(draw,"Residual norm");
3827: x = (PetscReal)n;
3828: if (rnorm > 0.0) y = PetscLog10Real(rnorm);
3829: else y = -15.0;
3830: PetscDrawLGAddPoint(lg,&x,&y);
3831: if (n < 20 || !(n % 5) || snes->reason) {
3832: PetscDrawLGDraw(lg);
3833: PetscDrawLGSave(lg);
3834: }
3836: PetscViewerDrawGetDrawLG(v,1,&lg);
3837: if (!n) {PetscDrawLGReset(lg);}
3838: PetscDrawLGGetDraw(lg,&draw);
3839: PetscDrawSetTitle(draw,"% elemts > .2*max elemt");
3840: SNESMonitorRange_Private(snes,n,&per);
3841: x = (PetscReal)n;
3842: y = 100.0*per;
3843: PetscDrawLGAddPoint(lg,&x,&y);
3844: if (n < 20 || !(n % 5) || snes->reason) {
3845: PetscDrawLGDraw(lg);
3846: PetscDrawLGSave(lg);
3847: }
3849: PetscViewerDrawGetDrawLG(v,2,&lg);
3850: if (!n) {prev = rnorm;PetscDrawLGReset(lg);}
3851: PetscDrawLGGetDraw(lg,&draw);
3852: PetscDrawSetTitle(draw,"(norm -oldnorm)/oldnorm");
3853: x = (PetscReal)n;
3854: y = (prev - rnorm)/prev;
3855: PetscDrawLGAddPoint(lg,&x,&y);
3856: if (n < 20 || !(n % 5) || snes->reason) {
3857: PetscDrawLGDraw(lg);
3858: PetscDrawLGSave(lg);
3859: }
3861: PetscViewerDrawGetDrawLG(v,3,&lg);
3862: if (!n) {PetscDrawLGReset(lg);}
3863: PetscDrawLGGetDraw(lg,&draw);
3864: PetscDrawSetTitle(draw,"(norm -oldnorm)/oldnorm*(% > .2 max)");
3865: x = (PetscReal)n;
3866: y = (prev - rnorm)/(prev*per);
3867: if (n > 2) { /*skip initial crazy value */
3868: PetscDrawLGAddPoint(lg,&x,&y);
3869: }
3870: if (n < 20 || !(n % 5) || snes->reason) {
3871: PetscDrawLGDraw(lg);
3872: PetscDrawLGSave(lg);
3873: }
3874: prev = rnorm;
3875: return(0);
3876: }
3878: /*@
3879: SNESMonitor - runs the user provided monitor routines, if they exist
3881: Collective on SNES
3883: Input Parameters:
3884: + snes - nonlinear solver context obtained from SNESCreate()
3885: . iter - iteration number
3886: - rnorm - relative norm of the residual
3888: Notes:
3889: This routine is called by the SNES implementations.
3890: It does not typically need to be called by the user.
3892: Level: developer
3894: .seealso: SNESMonitorSet()
3895: @*/
3896: PetscErrorCode SNESMonitor(SNES snes,PetscInt iter,PetscReal rnorm)
3897: {
3899: PetscInt i,n = snes->numbermonitors;
3902: VecLockReadPush(snes->vec_sol);
3903: for (i=0; i<n; i++) {
3904: (*snes->monitor[i])(snes,iter,rnorm,snes->monitorcontext[i]);
3905: }
3906: VecLockReadPop(snes->vec_sol);
3907: return(0);
3908: }
3910: /* ------------ Routines to set performance monitoring options ----------- */
3912: /*MC
3913: SNESMonitorFunction - functional form passed to SNESMonitorSet() to monitor convergence of nonlinear solver
3915: Synopsis:
3916: #include <petscsnes.h>
3917: $ PetscErrorCode SNESMonitorFunction(SNES snes,PetscInt its, PetscReal norm,void *mctx)
3919: Collective on snes
3921: Input Parameters:
3922: + snes - the SNES context
3923: . its - iteration number
3924: . norm - 2-norm function value (may be estimated)
3925: - mctx - [optional] monitoring context
3927: Level: advanced
3929: .seealso: SNESMonitorSet(), SNESMonitorGet()
3930: M*/
3932: /*@C
3933: SNESMonitorSet - Sets an ADDITIONAL function that is to be used at every
3934: iteration of the nonlinear solver to display the iteration's
3935: progress.
3937: Logically Collective on SNES
3939: Input Parameters:
3940: + snes - the SNES context
3941: . f - the monitor function, see SNESMonitorFunction for the calling sequence
3942: . mctx - [optional] user-defined context for private data for the
3943: monitor routine (use NULL if no context is desired)
3944: - monitordestroy - [optional] routine that frees monitor context
3945: (may be NULL)
3947: Options Database Keys:
3948: + -snes_monitor - sets SNESMonitorDefault()
3949: . -snes_monitor_lg_residualnorm - sets line graph monitor,
3950: uses SNESMonitorLGCreate()
3951: - -snes_monitor_cancel - cancels all monitors that have
3952: been hardwired into a code by
3953: calls to SNESMonitorSet(), but
3954: does not cancel those set via
3955: the options database.
3957: Notes:
3958: Several different monitoring routines may be set by calling
3959: SNESMonitorSet() multiple times; all will be called in the
3960: order in which they were set.
3962: Fortran Notes:
3963: Only a single monitor function can be set for each SNES object
3965: Level: intermediate
3967: .seealso: SNESMonitorDefault(), SNESMonitorCancel(), SNESMonitorFunction
3968: @*/
3969: PetscErrorCode SNESMonitorSet(SNES snes,PetscErrorCode (*f)(SNES,PetscInt,PetscReal,void*),void *mctx,PetscErrorCode (*monitordestroy)(void**))
3970: {
3971: PetscInt i;
3973: PetscBool identical;
3977: for (i=0; i<snes->numbermonitors;i++) {
3978: PetscMonitorCompare((PetscErrorCode (*)(void))f,mctx,monitordestroy,(PetscErrorCode (*)(void))snes->monitor[i],snes->monitorcontext[i],snes->monitordestroy[i],&identical);
3979: if (identical) return(0);
3980: }
3981: if (snes->numbermonitors >= MAXSNESMONITORS) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Too many monitors set");
3982: snes->monitor[snes->numbermonitors] = f;
3983: snes->monitordestroy[snes->numbermonitors] = monitordestroy;
3984: snes->monitorcontext[snes->numbermonitors++] = (void*)mctx;
3985: return(0);
3986: }
3988: /*@
3989: SNESMonitorCancel - Clears all the monitor functions for a SNES object.
3991: Logically Collective on SNES
3993: Input Parameters:
3994: . snes - the SNES context
3996: Options Database Key:
3997: . -snes_monitor_cancel - cancels all monitors that have been hardwired
3998: into a code by calls to SNESMonitorSet(), but does not cancel those
3999: set via the options database
4001: Notes:
4002: There is no way to clear one specific monitor from a SNES object.
4004: Level: intermediate
4006: .seealso: SNESMonitorDefault(), SNESMonitorSet()
4007: @*/
4008: PetscErrorCode SNESMonitorCancel(SNES snes)
4009: {
4011: PetscInt i;
4015: for (i=0; i<snes->numbermonitors; i++) {
4016: if (snes->monitordestroy[i]) {
4017: (*snes->monitordestroy[i])(&snes->monitorcontext[i]);
4018: }
4019: }
4020: snes->numbermonitors = 0;
4021: return(0);
4022: }
4024: /*MC
4025: SNESConvergenceTestFunction - functional form used for testing of convergence of nonlinear solver
4027: Synopsis:
4028: #include <petscsnes.h>
4029: $ PetscErrorCode SNESConvergenceTest(SNES snes,PetscInt it,PetscReal xnorm,PetscReal gnorm,PetscReal f,SNESConvergedReason *reason,void *cctx)
4031: Collective on snes
4033: Input Parameters:
4034: + snes - the SNES context
4035: . it - current iteration (0 is the first and is before any Newton step)
4036: . xnorm - 2-norm of current iterate
4037: . gnorm - 2-norm of current step
4038: . f - 2-norm of function
4039: - cctx - [optional] convergence context
4041: Output Parameter:
4042: . reason - reason for convergence/divergence, only needs to be set when convergence or divergence is detected
4044: Level: intermediate
4046: .seealso: SNESSetConvergenceTest(), SNESGetConvergenceTest()
4047: M*/
4049: /*@C
4050: SNESSetConvergenceTest - Sets the function that is to be used
4051: to test for convergence of the nonlinear iterative solution.
4053: Logically Collective on SNES
4055: Input Parameters:
4056: + snes - the SNES context
4057: . SNESConvergenceTestFunction - routine to test for convergence
4058: . cctx - [optional] context for private data for the convergence routine (may be NULL)
4059: - destroy - [optional] destructor for the context (may be NULL; PETSC_NULL_FUNCTION in Fortran)
4061: Level: advanced
4063: .seealso: SNESConvergedDefault(), SNESConvergedSkip(), SNESConvergenceTestFunction
4064: @*/
4065: PetscErrorCode SNESSetConvergenceTest(SNES snes,PetscErrorCode (*SNESConvergenceTestFunction)(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*),void *cctx,PetscErrorCode (*destroy)(void*))
4066: {
4071: if (!SNESConvergenceTestFunction) SNESConvergenceTestFunction = SNESConvergedSkip;
4072: if (snes->ops->convergeddestroy) {
4073: (*snes->ops->convergeddestroy)(snes->cnvP);
4074: }
4075: snes->ops->converged = SNESConvergenceTestFunction;
4076: snes->ops->convergeddestroy = destroy;
4077: snes->cnvP = cctx;
4078: return(0);
4079: }
4081: /*@
4082: SNESGetConvergedReason - Gets the reason the SNES iteration was stopped.
4084: Not Collective
4086: Input Parameter:
4087: . snes - the SNES context
4089: Output Parameter:
4090: . reason - negative value indicates diverged, positive value converged, see SNESConvergedReason or the
4091: manual pages for the individual convergence tests for complete lists
4093: Options Database:
4094: . -snes_converged_reason - prints the reason to standard out
4096: Level: intermediate
4098: Notes:
4099: Should only be called after the call the SNESSolve() is complete, if it is called earlier it returns the value SNES__CONVERGED_ITERATING.
4101: .seealso: SNESSetConvergenceTest(), SNESSetConvergedReason(), SNESConvergedReason
4102: @*/
4103: PetscErrorCode SNESGetConvergedReason(SNES snes,SNESConvergedReason *reason)
4104: {
4108: *reason = snes->reason;
4109: return(0);
4110: }
4112: /*@
4113: SNESSetConvergedReason - Sets the reason the SNES iteration was stopped.
4115: Not Collective
4117: Input Parameters:
4118: + snes - the SNES context
4119: - reason - negative value indicates diverged, positive value converged, see SNESConvergedReason or the
4120: manual pages for the individual convergence tests for complete lists
4122: Level: intermediate
4124: .seealso: SNESGetConvergedReason(), SNESSetConvergenceTest(), SNESConvergedReason
4125: @*/
4126: PetscErrorCode SNESSetConvergedReason(SNES snes,SNESConvergedReason reason)
4127: {
4130: snes->reason = reason;
4131: return(0);
4132: }
4134: /*@
4135: SNESSetConvergenceHistory - Sets the array used to hold the convergence history.
4137: Logically Collective on SNES
4139: Input Parameters:
4140: + snes - iterative context obtained from SNESCreate()
4141: . a - array to hold history, this array will contain the function norms computed at each step
4142: . its - integer array holds the number of linear iterations for each solve.
4143: . na - size of a and its
4144: - reset - PETSC_TRUE indicates each new nonlinear solve resets the history counter to zero,
4145: else it continues storing new values for new nonlinear solves after the old ones
4147: Notes:
4148: If 'a' and 'its' are NULL then space is allocated for the history. If 'na' PETSC_DECIDE or PETSC_DEFAULT then a
4149: default array of length 10000 is allocated.
4151: This routine is useful, e.g., when running a code for purposes
4152: of accurate performance monitoring, when no I/O should be done
4153: during the section of code that is being timed.
4155: Level: intermediate
4157: .seealso: SNESGetConvergenceHistory()
4159: @*/
4160: PetscErrorCode SNESSetConvergenceHistory(SNES snes,PetscReal a[],PetscInt its[],PetscInt na,PetscBool reset)
4161: {
4168: if (!a) {
4169: if (na == PETSC_DECIDE || na == PETSC_DEFAULT) na = 1000;
4170: PetscCalloc2(na,&a,na,&its);
4171: snes->conv_hist_alloc = PETSC_TRUE;
4172: }
4173: snes->conv_hist = a;
4174: snes->conv_hist_its = its;
4175: snes->conv_hist_max = na;
4176: snes->conv_hist_len = 0;
4177: snes->conv_hist_reset = reset;
4178: return(0);
4179: }
4181: #if defined(PETSC_HAVE_MATLAB_ENGINE)
4182: #include <engine.h> /* MATLAB include file */
4183: #include <mex.h> /* MATLAB include file */
4185: PETSC_EXTERN mxArray *SNESGetConvergenceHistoryMatlab(SNES snes)
4186: {
4187: mxArray *mat;
4188: PetscInt i;
4189: PetscReal *ar;
4192: mat = mxCreateDoubleMatrix(snes->conv_hist_len,1,mxREAL);
4193: ar = (PetscReal*) mxGetData(mat);
4194: for (i=0; i<snes->conv_hist_len; i++) ar[i] = snes->conv_hist[i];
4195: PetscFunctionReturn(mat);
4196: }
4197: #endif
4199: /*@C
4200: SNESGetConvergenceHistory - Gets the array used to hold the convergence history.
4202: Not Collective
4204: Input Parameter:
4205: . snes - iterative context obtained from SNESCreate()
4207: Output Parameters:
4208: + a - array to hold history
4209: . its - integer array holds the number of linear iterations (or
4210: negative if not converged) for each solve.
4211: - na - size of a and its
4213: Notes:
4214: The calling sequence for this routine in Fortran is
4215: $ call SNESGetConvergenceHistory(SNES snes, integer na, integer ierr)
4217: This routine is useful, e.g., when running a code for purposes
4218: of accurate performance monitoring, when no I/O should be done
4219: during the section of code that is being timed.
4221: Level: intermediate
4223: .seealso: SNESSetConvergenceHistory()
4225: @*/
4226: PetscErrorCode SNESGetConvergenceHistory(SNES snes,PetscReal *a[],PetscInt *its[],PetscInt *na)
4227: {
4230: if (a) *a = snes->conv_hist;
4231: if (its) *its = snes->conv_hist_its;
4232: if (na) *na = snes->conv_hist_len;
4233: return(0);
4234: }
4236: /*@C
4237: SNESSetUpdate - Sets the general-purpose update function called
4238: at the beginning of every iteration of the nonlinear solve. Specifically
4239: it is called just before the Jacobian is "evaluated".
4241: Logically Collective on SNES
4243: Input Parameters:
4244: + snes - The nonlinear solver context
4245: - func - The function
4247: Calling sequence of func:
4248: $ func (SNES snes, PetscInt step);
4250: . step - The current step of the iteration
4252: Level: advanced
4254: 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()
4255: This is not used by most users.
4257: .seealso SNESSetJacobian(), SNESSolve()
4258: @*/
4259: PetscErrorCode SNESSetUpdate(SNES snes, PetscErrorCode (*func)(SNES, PetscInt))
4260: {
4263: snes->ops->update = func;
4264: return(0);
4265: }
4267: /*
4268: SNESScaleStep_Private - Scales a step so that its length is less than the
4269: positive parameter delta.
4271: Input Parameters:
4272: + snes - the SNES context
4273: . y - approximate solution of linear system
4274: . fnorm - 2-norm of current function
4275: - delta - trust region size
4277: Output Parameters:
4278: + gpnorm - predicted function norm at the new point, assuming local
4279: linearization. The value is zero if the step lies within the trust
4280: region, and exceeds zero otherwise.
4281: - ynorm - 2-norm of the step
4283: Note:
4284: For non-trust region methods such as SNESNEWTONLS, the parameter delta
4285: is set to be the maximum allowable step size.
4287: */
4288: PetscErrorCode SNESScaleStep_Private(SNES snes,Vec y,PetscReal *fnorm,PetscReal *delta,PetscReal *gpnorm,PetscReal *ynorm)
4289: {
4290: PetscReal nrm;
4291: PetscScalar cnorm;
4299: VecNorm(y,NORM_2,&nrm);
4300: if (nrm > *delta) {
4301: nrm = *delta/nrm;
4302: *gpnorm = (1.0 - nrm)*(*fnorm);
4303: cnorm = nrm;
4304: VecScale(y,cnorm);
4305: *ynorm = *delta;
4306: } else {
4307: *gpnorm = 0.0;
4308: *ynorm = nrm;
4309: }
4310: return(0);
4311: }
4313: /*@C
4314: SNESConvergedReasonView - Displays the reason a SNES solve converged or diverged to a viewer
4316: Collective on SNES
4318: Parameter:
4319: + snes - iterative context obtained from SNESCreate()
4320: - viewer - the viewer to display the reason
4323: Options Database Keys:
4324: + -snes_converged_reason - print reason for converged or diverged, also prints number of iterations
4325: - -snes_converged_reason ::failed - only print reason and number of iterations when diverged
4327: Notes:
4328: To change the format of the output call PetscViewerPushFormat(viewer,format) before this call. Use PETSC_VIEWER_DEFAULT for the default,
4329: use PETSC_VIEWER_FAILED to only display a reason if it fails.
4331: Level: beginner
4333: .seealso: SNESCreate(), SNESSetUp(), SNESDestroy(), SNESSetTolerances(), SNESConvergedDefault(), SNESGetConvergedReason(), SNESConvergedReasonViewFromOptions(),
4334: PetscViewerPushFormat(), PetscViewerPopFormat()
4336: @*/
4337: PetscErrorCode SNESConvergedReasonView(SNES snes,PetscViewer viewer)
4338: {
4339: PetscViewerFormat format;
4340: PetscBool isAscii;
4341: PetscErrorCode ierr;
4344: if (!viewer) viewer = PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)snes));
4345: PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&isAscii);
4346: if (isAscii) {
4347: PetscViewerGetFormat(viewer, &format);
4348: PetscViewerASCIIAddTab(viewer,((PetscObject)snes)->tablevel);
4349: if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
4350: DM dm;
4351: Vec u;
4352: PetscDS prob;
4353: PetscInt Nf, f;
4354: PetscErrorCode (**exactSol)(PetscInt, PetscReal, const PetscReal[], PetscInt, PetscScalar[], void *);
4355: void **exactCtx;
4356: PetscReal error;
4358: SNESGetDM(snes, &dm);
4359: SNESGetSolution(snes, &u);
4360: DMGetDS(dm, &prob);
4361: PetscDSGetNumFields(prob, &Nf);
4362: PetscMalloc2(Nf, &exactSol, Nf, &exactCtx);
4363: for (f = 0; f < Nf; ++f) {PetscDSGetExactSolution(prob, f, &exactSol[f], &exactCtx[f]);}
4364: DMComputeL2Diff(dm, 0.0, exactSol, exactCtx, u, &error);
4365: PetscFree2(exactSol, exactCtx);
4366: if (error < 1.0e-11) {PetscViewerASCIIPrintf(viewer, "L_2 Error: < 1.0e-11\n");}
4367: else {PetscViewerASCIIPrintf(viewer, "L_2 Error: %g\n", error);}
4368: }
4369: if (snes->reason > 0 && format != PETSC_VIEWER_FAILED) {
4370: if (((PetscObject) snes)->prefix) {
4371: PetscViewerASCIIPrintf(viewer,"Nonlinear %s solve converged due to %s iterations %D\n",((PetscObject) snes)->prefix,SNESConvergedReasons[snes->reason],snes->iter);
4372: } else {
4373: PetscViewerASCIIPrintf(viewer,"Nonlinear solve converged due to %s iterations %D\n",SNESConvergedReasons[snes->reason],snes->iter);
4374: }
4375: } else if (snes->reason <= 0) {
4376: if (((PetscObject) snes)->prefix) {
4377: PetscViewerASCIIPrintf(viewer,"Nonlinear %s solve did not converge due to %s iterations %D\n",((PetscObject) snes)->prefix,SNESConvergedReasons[snes->reason],snes->iter);
4378: } else {
4379: PetscViewerASCIIPrintf(viewer,"Nonlinear solve did not converge due to %s iterations %D\n",SNESConvergedReasons[snes->reason],snes->iter);
4380: }
4381: }
4382: PetscViewerASCIISubtractTab(viewer,((PetscObject)snes)->tablevel);
4383: }
4384: return(0);
4385: }
4387: /*@
4388: SNESConvergedReasonViewFromOptions - Processes command line options to determine if/how a SNESReason is to be viewed.
4390: Collective on SNES
4392: Input Parameters:
4393: . snes - the SNES object
4395: Level: intermediate
4397: .seealso: SNESCreate(), SNESSetUp(), SNESDestroy(), SNESSetTolerances(), SNESConvergedDefault(), SNESGetConvergedReason(), SNESConvergedReasonView()
4399: @*/
4400: PetscErrorCode SNESConvergedReasonViewFromOptions(SNES snes)
4401: {
4402: PetscErrorCode ierr;
4403: PetscViewer viewer;
4404: PetscBool flg;
4405: static PetscBool incall = PETSC_FALSE;
4406: PetscViewerFormat format;
4409: if (incall) return(0);
4410: incall = PETSC_TRUE;
4411: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-snes_converged_reason",&viewer,&format,&flg);
4412: if (flg) {
4413: PetscViewerPushFormat(viewer,format);
4414: SNESConvergedReasonView(snes,viewer);
4415: PetscViewerPopFormat(viewer);
4416: PetscViewerDestroy(&viewer);
4417: }
4418: incall = PETSC_FALSE;
4419: return(0);
4420: }
4422: /*@
4423: SNESSolve - Solves a nonlinear system F(x) = b.
4424: Call SNESSolve() after calling SNESCreate() and optional routines of the form SNESSetXXX().
4426: Collective on SNES
4428: Input Parameters:
4429: + snes - the SNES context
4430: . b - the constant part of the equation F(x) = b, or NULL to use zero.
4431: - x - the solution vector.
4433: Notes:
4434: The user should initialize the vector,x, with the initial guess
4435: for the nonlinear solve prior to calling SNESSolve. In particular,
4436: to employ an initial guess of zero, the user should explicitly set
4437: this vector to zero by calling VecSet().
4439: Level: beginner
4441: .seealso: SNESCreate(), SNESDestroy(), SNESSetFunction(), SNESSetJacobian(), SNESSetGridSequence(), SNESGetSolution()
4442: @*/
4443: PetscErrorCode SNESSolve(SNES snes,Vec b,Vec x)
4444: {
4445: PetscErrorCode ierr;
4446: PetscBool flg;
4447: PetscInt grid;
4448: Vec xcreated = NULL;
4449: DM dm;
4458: /* High level operations using the nonlinear solver */
4459: {
4460: PetscViewer viewer;
4461: PetscViewerFormat format;
4462: PetscInt num;
4463: PetscBool flg;
4464: static PetscBool incall = PETSC_FALSE;
4466: if (!incall) {
4467: /* Estimate the convergence rate of the discretization */
4468: PetscOptionsGetViewer(PetscObjectComm((PetscObject) snes),((PetscObject)snes)->options, ((PetscObject) snes)->prefix, "-snes_convergence_estimate", &viewer, &format, &flg);
4469: if (flg) {
4470: PetscConvEst conv;
4471: DM dm;
4472: PetscReal *alpha; /* Convergence rate of the solution error for each field in the L_2 norm */
4473: PetscInt Nf;
4475: incall = PETSC_TRUE;
4476: SNESGetDM(snes, &dm);
4477: DMGetNumFields(dm, &Nf);
4478: PetscCalloc1(Nf, &alpha);
4479: PetscConvEstCreate(PetscObjectComm((PetscObject) snes), &conv);
4480: PetscConvEstSetSolver(conv, (PetscObject) snes);
4481: PetscConvEstSetFromOptions(conv);
4482: PetscConvEstSetUp(conv);
4483: PetscConvEstGetConvRate(conv, alpha);
4484: PetscViewerPushFormat(viewer, format);
4485: PetscConvEstRateView(conv, alpha, viewer);
4486: PetscViewerPopFormat(viewer);
4487: PetscViewerDestroy(&viewer);
4488: PetscConvEstDestroy(&conv);
4489: PetscFree(alpha);
4490: incall = PETSC_FALSE;
4491: }
4492: /* Adaptively refine the initial grid */
4493: num = 1;
4494: PetscOptionsGetInt(NULL, ((PetscObject) snes)->prefix, "-snes_adapt_initial", &num, &flg);
4495: if (flg) {
4496: DMAdaptor adaptor;
4498: incall = PETSC_TRUE;
4499: DMAdaptorCreate(PetscObjectComm((PetscObject)snes), &adaptor);
4500: DMAdaptorSetSolver(adaptor, snes);
4501: DMAdaptorSetSequenceLength(adaptor, num);
4502: DMAdaptorSetFromOptions(adaptor);
4503: DMAdaptorSetUp(adaptor);
4504: DMAdaptorAdapt(adaptor, x, DM_ADAPTATION_INITIAL, &dm, &x);
4505: DMAdaptorDestroy(&adaptor);
4506: incall = PETSC_FALSE;
4507: }
4508: /* Use grid sequencing to adapt */
4509: num = 0;
4510: PetscOptionsGetInt(NULL, ((PetscObject) snes)->prefix, "-snes_adapt_sequence", &num, NULL);
4511: if (num) {
4512: DMAdaptor adaptor;
4514: incall = PETSC_TRUE;
4515: DMAdaptorCreate(PetscObjectComm((PetscObject)snes), &adaptor);
4516: DMAdaptorSetSolver(adaptor, snes);
4517: DMAdaptorSetSequenceLength(adaptor, num);
4518: DMAdaptorSetFromOptions(adaptor);
4519: DMAdaptorSetUp(adaptor);
4520: DMAdaptorAdapt(adaptor, x, DM_ADAPTATION_SEQUENTIAL, &dm, &x);
4521: DMAdaptorDestroy(&adaptor);
4522: incall = PETSC_FALSE;
4523: }
4524: }
4525: }
4526: if (!x) {
4527: SNESGetDM(snes,&dm);
4528: DMCreateGlobalVector(dm,&xcreated);
4529: x = xcreated;
4530: }
4531: SNESViewFromOptions(snes,NULL,"-snes_view_pre");
4533: for (grid=0; grid<snes->gridsequence; grid++) {PetscViewerASCIIPushTab(PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)snes)));}
4534: for (grid=0; grid<snes->gridsequence+1; grid++) {
4536: /* set solution vector */
4537: if (!grid) {PetscObjectReference((PetscObject)x);}
4538: VecDestroy(&snes->vec_sol);
4539: snes->vec_sol = x;
4540: SNESGetDM(snes,&dm);
4542: /* set affine vector if provided */
4543: if (b) { PetscObjectReference((PetscObject)b); }
4544: VecDestroy(&snes->vec_rhs);
4545: snes->vec_rhs = b;
4547: if (snes->vec_rhs && (snes->vec_func == snes->vec_rhs)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_IDN,"Right hand side vector cannot be function vector");
4548: if (snes->vec_func == snes->vec_sol) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_IDN,"Solution vector cannot be function vector");
4549: if (snes->vec_rhs == snes->vec_sol) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_IDN,"Solution vector cannot be right hand side vector");
4550: if (!snes->vec_sol_update /* && snes->vec_sol */) {
4551: VecDuplicate(snes->vec_sol,&snes->vec_sol_update);
4552: PetscLogObjectParent((PetscObject)snes,(PetscObject)snes->vec_sol_update);
4553: }
4554: DMShellSetGlobalVector(dm,snes->vec_sol);
4555: SNESSetUp(snes);
4557: if (!grid) {
4558: if (snes->ops->computeinitialguess) {
4559: (*snes->ops->computeinitialguess)(snes,snes->vec_sol,snes->initialguessP);
4560: }
4561: }
4563: if (snes->conv_hist_reset) snes->conv_hist_len = 0;
4564: if (snes->counters_reset) {snes->nfuncs = 0; snes->linear_its = 0; snes->numFailures = 0;}
4566: PetscLogEventBegin(SNES_Solve,snes,0,0,0);
4567: (*snes->ops->solve)(snes);
4568: PetscLogEventEnd(SNES_Solve,snes,0,0,0);
4569: if (!snes->reason) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Internal error, solver returned without setting converged reason");
4570: snes->domainerror = PETSC_FALSE; /* clear the flag if it has been set */
4572: if (snes->lagjac_persist) snes->jac_iter += snes->iter;
4573: if (snes->lagpre_persist) snes->pre_iter += snes->iter;
4575: PetscOptionsGetViewer(PetscObjectComm((PetscObject)snes),((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-snes_test_local_min",NULL,NULL,&flg);
4576: if (flg && !PetscPreLoadingOn) { SNESTestLocalMin(snes); }
4577: SNESConvergedReasonViewFromOptions(snes);
4579: if (snes->errorifnotconverged && snes->reason < 0) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_NOT_CONVERGED,"SNESSolve has not converged");
4580: if (snes->reason < 0) break;
4581: if (grid < snes->gridsequence) {
4582: DM fine;
4583: Vec xnew;
4584: Mat interp;
4586: DMRefine(snes->dm,PetscObjectComm((PetscObject)snes),&fine);
4587: if (!fine) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_INCOMP,"DMRefine() did not perform any refinement, cannot continue grid sequencing");
4588: DMCreateInterpolation(snes->dm,fine,&interp,NULL);
4589: DMCreateGlobalVector(fine,&xnew);
4590: MatInterpolate(interp,x,xnew);
4591: DMInterpolate(snes->dm,interp,fine);
4592: MatDestroy(&interp);
4593: x = xnew;
4595: SNESReset(snes);
4596: SNESSetDM(snes,fine);
4597: SNESResetFromOptions(snes);
4598: DMDestroy(&fine);
4599: PetscViewerASCIIPopTab(PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)snes)));
4600: }
4601: }
4602: SNESViewFromOptions(snes,NULL,"-snes_view");
4603: VecViewFromOptions(snes->vec_sol,(PetscObject)snes,"-snes_view_solution");
4604: DMMonitor(snes->dm);
4606: VecDestroy(&xcreated);
4607: PetscObjectSAWsBlock((PetscObject)snes);
4608: return(0);
4609: }
4611: /* --------- Internal routines for SNES Package --------- */
4613: /*@C
4614: SNESSetType - Sets the method for the nonlinear solver.
4616: Collective on SNES
4618: Input Parameters:
4619: + snes - the SNES context
4620: - type - a known method
4622: Options Database Key:
4623: . -snes_type <type> - Sets the method; use -help for a list
4624: of available methods (for instance, newtonls or newtontr)
4626: Notes:
4627: See "petsc/include/petscsnes.h" for available methods (for instance)
4628: + SNESNEWTONLS - Newton's method with line search
4629: (systems of nonlinear equations)
4630: - SNESNEWTONTR - Newton's method with trust region
4631: (systems of nonlinear equations)
4633: Normally, it is best to use the SNESSetFromOptions() command and then
4634: set the SNES solver type from the options database rather than by using
4635: this routine. Using the options database provides the user with
4636: maximum flexibility in evaluating the many nonlinear solvers.
4637: The SNESSetType() routine is provided for those situations where it
4638: is necessary to set the nonlinear solver independently of the command
4639: line or options database. This might be the case, for example, when
4640: the choice of solver changes during the execution of the program,
4641: and the user's application is taking responsibility for choosing the
4642: appropriate method.
4644: Developer Notes:
4645: SNESRegister() adds a constructor for a new SNESType to SNESList, SNESSetType() locates
4646: the constructor in that list and calls it to create the spexific object.
4648: Level: intermediate
4650: .seealso: SNESType, SNESCreate(), SNESDestroy(), SNESGetType(), SNESSetFromOptions()
4652: @*/
4653: PetscErrorCode SNESSetType(SNES snes,SNESType type)
4654: {
4655: PetscErrorCode ierr,(*r)(SNES);
4656: PetscBool match;
4662: PetscObjectTypeCompare((PetscObject)snes,type,&match);
4663: if (match) return(0);
4665: PetscFunctionListFind(SNESList,type,&r);
4666: if (!r) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_UNKNOWN_TYPE,"Unable to find requested SNES type %s",type);
4667: /* Destroy the previous private SNES context */
4668: if (snes->ops->destroy) {
4669: (*(snes)->ops->destroy)(snes);
4670: snes->ops->destroy = NULL;
4671: }
4672: /* Reinitialize function pointers in SNESOps structure */
4673: snes->ops->setup = NULL;
4674: snes->ops->solve = NULL;
4675: snes->ops->view = NULL;
4676: snes->ops->setfromoptions = NULL;
4677: snes->ops->destroy = NULL;
4679: /* It may happen the user has customized the line search before calling SNESSetType */
4680: if (((PetscObject)snes)->type_name) {
4681: SNESLineSearchDestroy(&snes->linesearch);
4682: }
4684: /* Call the SNESCreate_XXX routine for this particular Nonlinear solver */
4685: snes->setupcalled = PETSC_FALSE;
4687: PetscObjectChangeTypeName((PetscObject)snes,type);
4688: (*r)(snes);
4689: return(0);
4690: }
4692: /*@C
4693: SNESGetType - Gets the SNES method type and name (as a string).
4695: Not Collective
4697: Input Parameter:
4698: . snes - nonlinear solver context
4700: Output Parameter:
4701: . type - SNES method (a character string)
4703: Level: intermediate
4705: @*/
4706: PetscErrorCode SNESGetType(SNES snes,SNESType *type)
4707: {
4711: *type = ((PetscObject)snes)->type_name;
4712: return(0);
4713: }
4715: /*@
4716: SNESSetSolution - Sets the solution vector for use by the SNES routines.
4718: Logically Collective on SNES
4720: Input Parameters:
4721: + snes - the SNES context obtained from SNESCreate()
4722: - u - the solution vector
4724: Level: beginner
4726: @*/
4727: PetscErrorCode SNESSetSolution(SNES snes, Vec u)
4728: {
4729: DM dm;
4735: PetscObjectReference((PetscObject) u);
4736: VecDestroy(&snes->vec_sol);
4738: snes->vec_sol = u;
4740: SNESGetDM(snes, &dm);
4741: DMShellSetGlobalVector(dm, u);
4742: return(0);
4743: }
4745: /*@
4746: SNESGetSolution - Returns the vector where the approximate solution is
4747: stored. This is the fine grid solution when using SNESSetGridSequence().
4749: Not Collective, but Vec is parallel if SNES is parallel
4751: Input Parameter:
4752: . snes - the SNES context
4754: Output Parameter:
4755: . x - the solution
4757: Level: intermediate
4759: .seealso: SNESGetSolutionUpdate(), SNESGetFunction()
4760: @*/
4761: PetscErrorCode SNESGetSolution(SNES snes,Vec *x)
4762: {
4766: *x = snes->vec_sol;
4767: return(0);
4768: }
4770: /*@
4771: SNESGetSolutionUpdate - Returns the vector where the solution update is
4772: stored.
4774: Not Collective, but Vec is parallel if SNES is parallel
4776: Input Parameter:
4777: . snes - the SNES context
4779: Output Parameter:
4780: . x - the solution update
4782: Level: advanced
4784: .seealso: SNESGetSolution(), SNESGetFunction()
4785: @*/
4786: PetscErrorCode SNESGetSolutionUpdate(SNES snes,Vec *x)
4787: {
4791: *x = snes->vec_sol_update;
4792: return(0);
4793: }
4795: /*@C
4796: SNESGetFunction - Returns the vector where the function is stored.
4798: Not Collective, but Vec is parallel if SNES is parallel. Collective if Vec is requested, but has not been created yet.
4800: Input Parameter:
4801: . snes - the SNES context
4803: Output Parameter:
4804: + r - the vector that is used to store residuals (or NULL if you don't want it)
4805: . f - the function (or NULL if you don't want it); see SNESFunction for calling sequence details
4806: - ctx - the function context (or NULL if you don't want it)
4808: Level: advanced
4810: Notes: The vector r DOES NOT, in general contain the current value of the SNES nonlinear function
4812: .seealso: SNESSetFunction(), SNESGetSolution(), SNESFunction
4813: @*/
4814: PetscErrorCode SNESGetFunction(SNES snes,Vec *r,PetscErrorCode (**f)(SNES,Vec,Vec,void*),void **ctx)
4815: {
4817: DM dm;
4821: if (r) {
4822: if (!snes->vec_func) {
4823: if (snes->vec_rhs) {
4824: VecDuplicate(snes->vec_rhs,&snes->vec_func);
4825: } else if (snes->vec_sol) {
4826: VecDuplicate(snes->vec_sol,&snes->vec_func);
4827: } else if (snes->dm) {
4828: DMCreateGlobalVector(snes->dm,&snes->vec_func);
4829: }
4830: }
4831: *r = snes->vec_func;
4832: }
4833: SNESGetDM(snes,&dm);
4834: DMSNESGetFunction(dm,f,ctx);
4835: return(0);
4836: }
4838: /*@C
4839: SNESGetNGS - Returns the NGS function and context.
4841: Input Parameter:
4842: . snes - the SNES context
4844: Output Parameter:
4845: + f - the function (or NULL) see SNESNGSFunction for details
4846: - ctx - the function context (or NULL)
4848: Level: advanced
4850: .seealso: SNESSetNGS(), SNESGetFunction()
4851: @*/
4853: PetscErrorCode SNESGetNGS (SNES snes, PetscErrorCode (**f)(SNES, Vec, Vec, void*), void ** ctx)
4854: {
4856: DM dm;
4860: SNESGetDM(snes,&dm);
4861: DMSNESGetNGS(dm,f,ctx);
4862: return(0);
4863: }
4865: /*@C
4866: SNESSetOptionsPrefix - Sets the prefix used for searching for all
4867: SNES options in the database.
4869: Logically Collective on SNES
4871: Input Parameter:
4872: + snes - the SNES context
4873: - prefix - the prefix to prepend to all option names
4875: Notes:
4876: A hyphen (-) must NOT be given at the beginning of the prefix name.
4877: The first character of all runtime options is AUTOMATICALLY the hyphen.
4879: Level: advanced
4881: .seealso: SNESSetFromOptions()
4882: @*/
4883: PetscErrorCode SNESSetOptionsPrefix(SNES snes,const char prefix[])
4884: {
4889: PetscObjectSetOptionsPrefix((PetscObject)snes,prefix);
4890: if (!snes->ksp) {SNESGetKSP(snes,&snes->ksp);}
4891: if (snes->linesearch) {
4892: SNESGetLineSearch(snes,&snes->linesearch);
4893: PetscObjectSetOptionsPrefix((PetscObject)snes->linesearch,prefix);
4894: }
4895: KSPSetOptionsPrefix(snes->ksp,prefix);
4896: return(0);
4897: }
4899: /*@C
4900: SNESAppendOptionsPrefix - Appends to the prefix used for searching for all
4901: SNES options in the database.
4903: Logically Collective on SNES
4905: Input Parameters:
4906: + snes - the SNES context
4907: - prefix - the prefix to prepend to all option names
4909: Notes:
4910: A hyphen (-) must NOT be given at the beginning of the prefix name.
4911: The first character of all runtime options is AUTOMATICALLY the hyphen.
4913: Level: advanced
4915: .seealso: SNESGetOptionsPrefix()
4916: @*/
4917: PetscErrorCode SNESAppendOptionsPrefix(SNES snes,const char prefix[])
4918: {
4923: PetscObjectAppendOptionsPrefix((PetscObject)snes,prefix);
4924: if (!snes->ksp) {SNESGetKSP(snes,&snes->ksp);}
4925: if (snes->linesearch) {
4926: SNESGetLineSearch(snes,&snes->linesearch);
4927: PetscObjectAppendOptionsPrefix((PetscObject)snes->linesearch,prefix);
4928: }
4929: KSPAppendOptionsPrefix(snes->ksp,prefix);
4930: return(0);
4931: }
4933: /*@C
4934: SNESGetOptionsPrefix - Sets the prefix used for searching for all
4935: SNES options in the database.
4937: Not Collective
4939: Input Parameter:
4940: . snes - the SNES context
4942: Output Parameter:
4943: . prefix - pointer to the prefix string used
4945: Notes:
4946: On the fortran side, the user should pass in a string 'prefix' of
4947: sufficient length to hold the prefix.
4949: Level: advanced
4951: .seealso: SNESAppendOptionsPrefix()
4952: @*/
4953: PetscErrorCode SNESGetOptionsPrefix(SNES snes,const char *prefix[])
4954: {
4959: PetscObjectGetOptionsPrefix((PetscObject)snes,prefix);
4960: return(0);
4961: }
4964: /*@C
4965: SNESRegister - Adds a method to the nonlinear solver package.
4967: Not collective
4969: Input Parameters:
4970: + name_solver - name of a new user-defined solver
4971: - routine_create - routine to create method context
4973: Notes:
4974: SNESRegister() may be called multiple times to add several user-defined solvers.
4976: Sample usage:
4977: .vb
4978: SNESRegister("my_solver",MySolverCreate);
4979: .ve
4981: Then, your solver can be chosen with the procedural interface via
4982: $ SNESSetType(snes,"my_solver")
4983: or at runtime via the option
4984: $ -snes_type my_solver
4986: Level: advanced
4988: Note: If your function is not being put into a shared library then use SNESRegister() instead
4990: .seealso: SNESRegisterAll(), SNESRegisterDestroy()
4992: Level: advanced
4993: @*/
4994: PetscErrorCode SNESRegister(const char sname[],PetscErrorCode (*function)(SNES))
4995: {
4999: SNESInitializePackage();
5000: PetscFunctionListAdd(&SNESList,sname,function);
5001: return(0);
5002: }
5004: PetscErrorCode SNESTestLocalMin(SNES snes)
5005: {
5007: PetscInt N,i,j;
5008: Vec u,uh,fh;
5009: PetscScalar value;
5010: PetscReal norm;
5013: SNESGetSolution(snes,&u);
5014: VecDuplicate(u,&uh);
5015: VecDuplicate(u,&fh);
5017: /* currently only works for sequential */
5018: PetscPrintf(PetscObjectComm((PetscObject)snes),"Testing FormFunction() for local min\n");
5019: VecGetSize(u,&N);
5020: for (i=0; i<N; i++) {
5021: VecCopy(u,uh);
5022: PetscPrintf(PetscObjectComm((PetscObject)snes),"i = %D\n",i);
5023: for (j=-10; j<11; j++) {
5024: value = PetscSign(j)*PetscExpReal(PetscAbs(j)-10.0);
5025: VecSetValue(uh,i,value,ADD_VALUES);
5026: SNESComputeFunction(snes,uh,fh);
5027: VecNorm(fh,NORM_2,&norm);
5028: PetscPrintf(PetscObjectComm((PetscObject)snes)," j norm %D %18.16e\n",j,norm);
5029: value = -value;
5030: VecSetValue(uh,i,value,ADD_VALUES);
5031: }
5032: }
5033: VecDestroy(&uh);
5034: VecDestroy(&fh);
5035: return(0);
5036: }
5038: /*@
5039: SNESKSPSetUseEW - Sets SNES use Eisenstat-Walker method for
5040: computing relative tolerance for linear solvers within an inexact
5041: Newton method.
5043: Logically Collective on SNES
5045: Input Parameters:
5046: + snes - SNES context
5047: - flag - PETSC_TRUE or PETSC_FALSE
5049: Options Database:
5050: + -snes_ksp_ew - use Eisenstat-Walker method for determining linear system convergence
5051: . -snes_ksp_ew_version ver - version of Eisenstat-Walker method
5052: . -snes_ksp_ew_rtol0 <rtol0> - Sets rtol0
5053: . -snes_ksp_ew_rtolmax <rtolmax> - Sets rtolmax
5054: . -snes_ksp_ew_gamma <gamma> - Sets gamma
5055: . -snes_ksp_ew_alpha <alpha> - Sets alpha
5056: . -snes_ksp_ew_alpha2 <alpha2> - Sets alpha2
5057: - -snes_ksp_ew_threshold <threshold> - Sets threshold
5059: Notes:
5060: Currently, the default is to use a constant relative tolerance for
5061: the inner linear solvers. Alternatively, one can use the
5062: Eisenstat-Walker method, where the relative convergence tolerance
5063: is reset at each Newton iteration according progress of the nonlinear
5064: solver.
5066: Level: advanced
5068: Reference:
5069: S. C. Eisenstat and H. F. Walker, "Choosing the forcing terms in an
5070: inexact Newton method", SISC 17 (1), pp.16-32, 1996.
5072: .seealso: SNESKSPGetUseEW(), SNESKSPGetParametersEW(), SNESKSPSetParametersEW()
5073: @*/
5074: PetscErrorCode SNESKSPSetUseEW(SNES snes,PetscBool flag)
5075: {
5079: snes->ksp_ewconv = flag;
5080: return(0);
5081: }
5083: /*@
5084: SNESKSPGetUseEW - Gets if SNES is using Eisenstat-Walker method
5085: for computing relative tolerance for linear solvers within an
5086: inexact Newton method.
5088: Not Collective
5090: Input Parameter:
5091: . snes - SNES context
5093: Output Parameter:
5094: . flag - PETSC_TRUE or PETSC_FALSE
5096: Notes:
5097: Currently, the default is to use a constant relative tolerance for
5098: the inner linear solvers. Alternatively, one can use the
5099: Eisenstat-Walker method, where the relative convergence tolerance
5100: is reset at each Newton iteration according progress of the nonlinear
5101: solver.
5103: Level: advanced
5105: Reference:
5106: S. C. Eisenstat and H. F. Walker, "Choosing the forcing terms in an
5107: inexact Newton method", SISC 17 (1), pp.16-32, 1996.
5109: .seealso: SNESKSPSetUseEW(), SNESKSPGetParametersEW(), SNESKSPSetParametersEW()
5110: @*/
5111: PetscErrorCode SNESKSPGetUseEW(SNES snes, PetscBool *flag)
5112: {
5116: *flag = snes->ksp_ewconv;
5117: return(0);
5118: }
5120: /*@
5121: SNESKSPSetParametersEW - Sets parameters for Eisenstat-Walker
5122: convergence criteria for the linear solvers within an inexact
5123: Newton method.
5125: Logically Collective on SNES
5127: Input Parameters:
5128: + snes - SNES context
5129: . version - version 1, 2 (default is 2) or 3
5130: . rtol_0 - initial relative tolerance (0 <= rtol_0 < 1)
5131: . rtol_max - maximum relative tolerance (0 <= rtol_max < 1)
5132: . gamma - multiplicative factor for version 2 rtol computation
5133: (0 <= gamma2 <= 1)
5134: . alpha - power for version 2 rtol computation (1 < alpha <= 2)
5135: . alpha2 - power for safeguard
5136: - threshold - threshold for imposing safeguard (0 < threshold < 1)
5138: Note:
5139: Version 3 was contributed by Luis Chacon, June 2006.
5141: Use PETSC_DEFAULT to retain the default for any of the parameters.
5143: Level: advanced
5145: Reference:
5146: S. C. Eisenstat and H. F. Walker, "Choosing the forcing terms in an
5147: inexact Newton method", Utah State University Math. Stat. Dept. Res.
5148: Report 6/94/75, June, 1994, to appear in SIAM J. Sci. Comput.
5150: .seealso: SNESKSPSetUseEW(), SNESKSPGetUseEW(), SNESKSPGetParametersEW()
5151: @*/
5152: PetscErrorCode SNESKSPSetParametersEW(SNES snes,PetscInt version,PetscReal rtol_0,PetscReal rtol_max,PetscReal gamma,PetscReal alpha,PetscReal alpha2,PetscReal threshold)
5153: {
5154: SNESKSPEW *kctx;
5158: kctx = (SNESKSPEW*)snes->kspconvctx;
5159: if (!kctx) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"No Eisenstat-Walker context existing");
5168: if (version != PETSC_DEFAULT) kctx->version = version;
5169: if (rtol_0 != PETSC_DEFAULT) kctx->rtol_0 = rtol_0;
5170: if (rtol_max != PETSC_DEFAULT) kctx->rtol_max = rtol_max;
5171: if (gamma != PETSC_DEFAULT) kctx->gamma = gamma;
5172: if (alpha != PETSC_DEFAULT) kctx->alpha = alpha;
5173: if (alpha2 != PETSC_DEFAULT) kctx->alpha2 = alpha2;
5174: if (threshold != PETSC_DEFAULT) kctx->threshold = threshold;
5176: 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);
5177: 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);
5178: 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);
5179: 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);
5180: 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);
5181: 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);
5182: return(0);
5183: }
5185: /*@
5186: SNESKSPGetParametersEW - Gets parameters for Eisenstat-Walker
5187: convergence criteria for the linear solvers within an inexact
5188: Newton method.
5190: Not Collective
5192: Input Parameters:
5193: snes - SNES context
5195: Output Parameters:
5196: + version - version 1, 2 (default is 2) or 3
5197: . rtol_0 - initial relative tolerance (0 <= rtol_0 < 1)
5198: . rtol_max - maximum relative tolerance (0 <= rtol_max < 1)
5199: . gamma - multiplicative factor for version 2 rtol computation (0 <= gamma2 <= 1)
5200: . alpha - power for version 2 rtol computation (1 < alpha <= 2)
5201: . alpha2 - power for safeguard
5202: - threshold - threshold for imposing safeguard (0 < threshold < 1)
5204: Level: advanced
5206: .seealso: SNESKSPSetUseEW(), SNESKSPGetUseEW(), SNESKSPSetParametersEW()
5207: @*/
5208: PetscErrorCode SNESKSPGetParametersEW(SNES snes,PetscInt *version,PetscReal *rtol_0,PetscReal *rtol_max,PetscReal *gamma,PetscReal *alpha,PetscReal *alpha2,PetscReal *threshold)
5209: {
5210: SNESKSPEW *kctx;
5214: kctx = (SNESKSPEW*)snes->kspconvctx;
5215: if (!kctx) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"No Eisenstat-Walker context existing");
5216: if (version) *version = kctx->version;
5217: if (rtol_0) *rtol_0 = kctx->rtol_0;
5218: if (rtol_max) *rtol_max = kctx->rtol_max;
5219: if (gamma) *gamma = kctx->gamma;
5220: if (alpha) *alpha = kctx->alpha;
5221: if (alpha2) *alpha2 = kctx->alpha2;
5222: if (threshold) *threshold = kctx->threshold;
5223: return(0);
5224: }
5226: PetscErrorCode KSPPreSolve_SNESEW(KSP ksp, Vec b, Vec x, SNES snes)
5227: {
5229: SNESKSPEW *kctx = (SNESKSPEW*)snes->kspconvctx;
5230: PetscReal rtol = PETSC_DEFAULT,stol;
5233: if (!snes->ksp_ewconv) return(0);
5234: if (!snes->iter) {
5235: rtol = kctx->rtol_0; /* first time in, so use the original user rtol */
5236: VecNorm(snes->vec_func,NORM_2,&kctx->norm_first);
5237: }
5238: else {
5239: if (kctx->version == 1) {
5240: rtol = (snes->norm - kctx->lresid_last)/kctx->norm_last;
5241: if (rtol < 0.0) rtol = -rtol;
5242: stol = PetscPowReal(kctx->rtol_last,kctx->alpha2);
5243: if (stol > kctx->threshold) rtol = PetscMax(rtol,stol);
5244: } else if (kctx->version == 2) {
5245: rtol = kctx->gamma * PetscPowReal(snes->norm/kctx->norm_last,kctx->alpha);
5246: stol = kctx->gamma * PetscPowReal(kctx->rtol_last,kctx->alpha);
5247: if (stol > kctx->threshold) rtol = PetscMax(rtol,stol);
5248: } else if (kctx->version == 3) { /* contributed by Luis Chacon, June 2006. */
5249: rtol = kctx->gamma * PetscPowReal(snes->norm/kctx->norm_last,kctx->alpha);
5250: /* safeguard: avoid sharp decrease of rtol */
5251: stol = kctx->gamma*PetscPowReal(kctx->rtol_last,kctx->alpha);
5252: stol = PetscMax(rtol,stol);
5253: rtol = PetscMin(kctx->rtol_0,stol);
5254: /* safeguard: avoid oversolving */
5255: stol = kctx->gamma*(kctx->norm_first*snes->rtol)/snes->norm;
5256: stol = PetscMax(rtol,stol);
5257: rtol = PetscMin(kctx->rtol_0,stol);
5258: } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Only versions 1, 2 or 3 are supported: %D",kctx->version);
5259: }
5260: /* safeguard: avoid rtol greater than one */
5261: rtol = PetscMin(rtol,kctx->rtol_max);
5262: KSPSetTolerances(ksp,rtol,PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT);
5263: PetscInfo3(snes,"iter %D, Eisenstat-Walker (version %D) KSP rtol=%g\n",snes->iter,kctx->version,(double)rtol);
5264: return(0);
5265: }
5267: PetscErrorCode KSPPostSolve_SNESEW(KSP ksp, Vec b, Vec x, SNES snes)
5268: {
5270: SNESKSPEW *kctx = (SNESKSPEW*)snes->kspconvctx;
5271: PCSide pcside;
5272: Vec lres;
5275: if (!snes->ksp_ewconv) return(0);
5276: KSPGetTolerances(ksp,&kctx->rtol_last,NULL,NULL,NULL);
5277: kctx->norm_last = snes->norm;
5278: if (kctx->version == 1) {
5279: PC pc;
5280: PetscBool isNone;
5282: KSPGetPC(ksp, &pc);
5283: PetscObjectTypeCompare((PetscObject) pc, PCNONE, &isNone);
5284: KSPGetPCSide(ksp,&pcside);
5285: if (pcside == PC_RIGHT || isNone) { /* XXX Should we also test KSP_UNPRECONDITIONED_NORM ? */
5286: /* KSP residual is true linear residual */
5287: KSPGetResidualNorm(ksp,&kctx->lresid_last);
5288: } else {
5289: /* KSP residual is preconditioned residual */
5290: /* compute true linear residual norm */
5291: VecDuplicate(b,&lres);
5292: MatMult(snes->jacobian,x,lres);
5293: VecAYPX(lres,-1.0,b);
5294: VecNorm(lres,NORM_2,&kctx->lresid_last);
5295: VecDestroy(&lres);
5296: }
5297: }
5298: return(0);
5299: }
5301: /*@
5302: SNESGetKSP - Returns the KSP context for a SNES solver.
5304: Not Collective, but if SNES object is parallel, then KSP object is parallel
5306: Input Parameter:
5307: . snes - the SNES context
5309: Output Parameter:
5310: . ksp - the KSP context
5312: Notes:
5313: The user can then directly manipulate the KSP context to set various
5314: options, etc. Likewise, the user can then extract and manipulate the
5315: PC contexts as well.
5317: Level: beginner
5319: .seealso: KSPGetPC(), SNESCreate(), KSPCreate(), SNESSetKSP()
5320: @*/
5321: PetscErrorCode SNESGetKSP(SNES snes,KSP *ksp)
5322: {
5329: if (!snes->ksp) {
5330: PetscBool monitor = PETSC_FALSE;
5332: KSPCreate(PetscObjectComm((PetscObject)snes),&snes->ksp);
5333: PetscObjectIncrementTabLevel((PetscObject)snes->ksp,(PetscObject)snes,1);
5334: PetscLogObjectParent((PetscObject)snes,(PetscObject)snes->ksp);
5336: KSPSetPreSolve(snes->ksp,(PetscErrorCode (*)(KSP,Vec,Vec,void*))KSPPreSolve_SNESEW,snes);
5337: KSPSetPostSolve(snes->ksp,(PetscErrorCode (*)(KSP,Vec,Vec,void*))KSPPostSolve_SNESEW,snes);
5339: PetscOptionsGetBool(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-ksp_monitor_snes",&monitor,NULL);
5340: if (monitor) {
5341: KSPMonitorSet(snes->ksp,KSPMonitorSNES,snes,NULL);
5342: }
5343: monitor = PETSC_FALSE;
5344: PetscOptionsGetBool(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-ksp_monitor_snes_lg",&monitor,NULL);
5345: if (monitor) {
5346: PetscObject *objs;
5347: KSPMonitorSNESLGResidualNormCreate(PetscObjectComm((PetscObject)snes),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,600,600,&objs);
5348: objs[0] = (PetscObject) snes;
5349: KSPMonitorSet(snes->ksp,(PetscErrorCode (*)(KSP,PetscInt,PetscReal,void*))KSPMonitorSNESLGResidualNorm,objs,(PetscErrorCode (*)(void**))KSPMonitorSNESLGResidualNormDestroy);
5350: }
5351: PetscObjectSetOptions((PetscObject)snes->ksp,((PetscObject)snes)->options);
5352: }
5353: *ksp = snes->ksp;
5354: return(0);
5355: }
5358: #include <petsc/private/dmimpl.h>
5359: /*@
5360: SNESSetDM - Sets the DM that may be used by some nonlinear solvers or their underlying preconditioners
5362: Logically Collective on SNES
5364: Input Parameters:
5365: + snes - the nonlinear solver context
5366: - dm - the dm, cannot be NULL
5368: Notes:
5369: A DM can only be used for solving one problem at a time because information about the problem is stored on the DM,
5370: even when not using interfaces like DMSNESSetFunction(). Use DMClone() to get a distinct DM when solving different
5371: problems using the same function space.
5373: Level: intermediate
5375: .seealso: SNESGetDM(), KSPSetDM(), KSPGetDM()
5376: @*/
5377: PetscErrorCode SNESSetDM(SNES snes,DM dm)
5378: {
5380: KSP ksp;
5381: DMSNES sdm;
5386: PetscObjectReference((PetscObject)dm);
5387: if (snes->dm) { /* Move the DMSNES context over to the new DM unless the new DM already has one */
5388: if (snes->dm->dmsnes && !dm->dmsnes) {
5389: DMCopyDMSNES(snes->dm,dm);
5390: DMGetDMSNES(snes->dm,&sdm);
5391: if (sdm->originaldm == snes->dm) sdm->originaldm = dm; /* Grant write privileges to the replacement DM */
5392: }
5393: DMCoarsenHookRemove(snes->dm,DMCoarsenHook_SNESVecSol,DMRestrictHook_SNESVecSol,snes);
5394: DMDestroy(&snes->dm);
5395: }
5396: snes->dm = dm;
5397: snes->dmAuto = PETSC_FALSE;
5399: SNESGetKSP(snes,&ksp);
5400: KSPSetDM(ksp,dm);
5401: KSPSetDMActive(ksp,PETSC_FALSE);
5402: if (snes->npc) {
5403: SNESSetDM(snes->npc, snes->dm);
5404: SNESSetNPCSide(snes,snes->npcside);
5405: }
5406: return(0);
5407: }
5409: /*@
5410: SNESGetDM - Gets the DM that may be used by some preconditioners
5412: Not Collective but DM obtained is parallel on SNES
5414: Input Parameter:
5415: . snes - the preconditioner context
5417: Output Parameter:
5418: . dm - the dm
5420: Level: intermediate
5422: .seealso: SNESSetDM(), KSPSetDM(), KSPGetDM()
5423: @*/
5424: PetscErrorCode SNESGetDM(SNES snes,DM *dm)
5425: {
5430: if (!snes->dm) {
5431: DMShellCreate(PetscObjectComm((PetscObject)snes),&snes->dm);
5432: snes->dmAuto = PETSC_TRUE;
5433: }
5434: *dm = snes->dm;
5435: return(0);
5436: }
5438: /*@
5439: SNESSetNPC - Sets the nonlinear preconditioner to be used.
5441: Collective on SNES
5443: Input Parameters:
5444: + snes - iterative context obtained from SNESCreate()
5445: - pc - the preconditioner object
5447: Notes:
5448: Use SNESGetNPC() to retrieve the preconditioner context (for example,
5449: to configure it using the API).
5451: Level: developer
5453: .seealso: SNESGetNPC(), SNESHasNPC()
5454: @*/
5455: PetscErrorCode SNESSetNPC(SNES snes, SNES pc)
5456: {
5463: PetscObjectReference((PetscObject) pc);
5464: SNESDestroy(&snes->npc);
5465: snes->npc = pc;
5466: PetscLogObjectParent((PetscObject)snes, (PetscObject)snes->npc);
5467: return(0);
5468: }
5470: /*@
5471: SNESGetNPC - Creates a nonlinear preconditioning solver (SNES) to be used to precondition the nonlinear solver.
5473: Not Collective; but any changes to the obtained SNES object must be applied collectively
5475: Input Parameter:
5476: . snes - iterative context obtained from SNESCreate()
5478: Output Parameter:
5479: . pc - preconditioner context
5481: Options Database:
5482: . -npc_snes_type <type> - set the type of the SNES to use as the nonlinear preconditioner
5484: Notes:
5485: If a SNES was previously set with SNESSetNPC() then that SNES is returned, otherwise a new SNES object is created.
5487: The (preconditioner) SNES returned automatically inherits the same nonlinear function and Jacobian supplied to the original
5488: SNES during SNESSetUp()
5490: Level: developer
5492: .seealso: SNESSetNPC(), SNESHasNPC(), SNES, SNESCreate()
5493: @*/
5494: PetscErrorCode SNESGetNPC(SNES snes, SNES *pc)
5495: {
5497: const char *optionsprefix;
5502: if (!snes->npc) {
5503: SNESCreate(PetscObjectComm((PetscObject)snes),&snes->npc);
5504: PetscObjectIncrementTabLevel((PetscObject)snes->npc,(PetscObject)snes,1);
5505: PetscLogObjectParent((PetscObject)snes,(PetscObject)snes->npc);
5506: SNESGetOptionsPrefix(snes,&optionsprefix);
5507: SNESSetOptionsPrefix(snes->npc,optionsprefix);
5508: SNESAppendOptionsPrefix(snes->npc,"npc_");
5509: SNESSetCountersReset(snes->npc,PETSC_FALSE);
5510: }
5511: *pc = snes->npc;
5512: return(0);
5513: }
5515: /*@
5516: SNESHasNPC - Returns whether a nonlinear preconditioner exists
5518: Not Collective
5520: Input Parameter:
5521: . snes - iterative context obtained from SNESCreate()
5523: Output Parameter:
5524: . has_npc - whether the SNES has an NPC or not
5526: Level: developer
5528: .seealso: SNESSetNPC(), SNESGetNPC()
5529: @*/
5530: PetscErrorCode SNESHasNPC(SNES snes, PetscBool *has_npc)
5531: {
5534: *has_npc = (PetscBool) (snes->npc ? PETSC_TRUE : PETSC_FALSE);
5535: return(0);
5536: }
5538: /*@
5539: SNESSetNPCSide - Sets the preconditioning side.
5541: Logically Collective on SNES
5543: Input Parameter:
5544: . snes - iterative context obtained from SNESCreate()
5546: Output Parameter:
5547: . side - the preconditioning side, where side is one of
5548: .vb
5549: PC_LEFT - left preconditioning
5550: PC_RIGHT - right preconditioning (default for most nonlinear solvers)
5551: .ve
5553: Options Database Keys:
5554: . -snes_pc_side <right,left>
5556: Notes:
5557: SNESNRICHARDSON and SNESNCG only support left preconditioning.
5559: Level: intermediate
5561: .seealso: SNESGetNPCSide(), KSPSetPCSide()
5562: @*/
5563: PetscErrorCode SNESSetNPCSide(SNES snes,PCSide side)
5564: {
5568: snes->npcside= side;
5569: return(0);
5570: }
5572: /*@
5573: SNESGetNPCSide - Gets the preconditioning side.
5575: Not Collective
5577: Input Parameter:
5578: . snes - iterative context obtained from SNESCreate()
5580: Output Parameter:
5581: . side - the preconditioning side, where side is one of
5582: .vb
5583: PC_LEFT - left preconditioning
5584: PC_RIGHT - right preconditioning (default for most nonlinear solvers)
5585: .ve
5587: Level: intermediate
5589: .seealso: SNESSetNPCSide(), KSPGetPCSide()
5590: @*/
5591: PetscErrorCode SNESGetNPCSide(SNES snes,PCSide *side)
5592: {
5596: *side = snes->npcside;
5597: return(0);
5598: }
5600: /*@
5601: SNESSetLineSearch - Sets the linesearch on the SNES instance.
5603: Collective on SNES
5605: Input Parameters:
5606: + snes - iterative context obtained from SNESCreate()
5607: - linesearch - the linesearch object
5609: Notes:
5610: Use SNESGetLineSearch() to retrieve the preconditioner context (for example,
5611: to configure it using the API).
5613: Level: developer
5615: .seealso: SNESGetLineSearch()
5616: @*/
5617: PetscErrorCode SNESSetLineSearch(SNES snes, SNESLineSearch linesearch)
5618: {
5625: PetscObjectReference((PetscObject) linesearch);
5626: SNESLineSearchDestroy(&snes->linesearch);
5628: snes->linesearch = linesearch;
5630: PetscLogObjectParent((PetscObject)snes, (PetscObject)snes->linesearch);
5631: return(0);
5632: }
5634: /*@
5635: SNESGetLineSearch - Returns a pointer to the line search context set with SNESSetLineSearch()
5636: or creates a default line search instance associated with the SNES and returns it.
5638: Not Collective
5640: Input Parameter:
5641: . snes - iterative context obtained from SNESCreate()
5643: Output Parameter:
5644: . linesearch - linesearch context
5646: Level: beginner
5648: .seealso: SNESSetLineSearch(), SNESLineSearchCreate()
5649: @*/
5650: PetscErrorCode SNESGetLineSearch(SNES snes, SNESLineSearch *linesearch)
5651: {
5653: const char *optionsprefix;
5658: if (!snes->linesearch) {
5659: SNESGetOptionsPrefix(snes, &optionsprefix);
5660: SNESLineSearchCreate(PetscObjectComm((PetscObject)snes), &snes->linesearch);
5661: SNESLineSearchSetSNES(snes->linesearch, snes);
5662: SNESLineSearchAppendOptionsPrefix(snes->linesearch, optionsprefix);
5663: PetscObjectIncrementTabLevel((PetscObject) snes->linesearch, (PetscObject) snes, 1);
5664: PetscLogObjectParent((PetscObject)snes, (PetscObject)snes->linesearch);
5665: }
5666: *linesearch = snes->linesearch;
5667: return(0);
5668: }