Actual source code: snesut.c


  2: #include <petsc/private/snesimpl.h>
  3: #include <petscdm.h>
  4: #include <petscsection.h>
  5: #include <petscblaslapack.h>

  7: /*@C
  8:    SNESMonitorSolution - Monitors progress of the SNES solvers by calling
  9:    VecView() for the approximate solution at each iteration.

 11:    Collective on SNES

 13:    Input Parameters:
 14: +  snes - the SNES context
 15: .  its - iteration number
 16: .  fgnorm - 2-norm of residual
 17: -  dummy -  a viewer

 19:    Options Database Keys:
 20: .  -snes_monitor_solution [ascii binary draw][:filename][:viewer format] - plots solution at each iteration

 22:    Level: intermediate

 24: .seealso: SNESMonitorSet(), SNESMonitorDefault(), VecView()
 25: @*/
 26: PetscErrorCode  SNESMonitorSolution(SNES snes,PetscInt its,PetscReal fgnorm,PetscViewerAndFormat *vf)
 27: {
 29:   Vec            x;
 30:   PetscViewer    viewer = vf->viewer;

 34:   SNESGetSolution(snes,&x);
 35:   PetscViewerPushFormat(viewer,vf->format);
 36:   VecView(x,viewer);
 37:   PetscViewerPopFormat(viewer);
 38:   return(0);
 39: }

 41: /*@C
 42:    SNESMonitorResidual - Monitors progress of the SNES solvers by calling
 43:    VecView() for the residual at each iteration.

 45:    Collective on SNES

 47:    Input Parameters:
 48: +  snes - the SNES context
 49: .  its - iteration number
 50: .  fgnorm - 2-norm of residual
 51: -  dummy -  a viewer

 53:    Options Database Keys:
 54: .  -snes_monitor_residual [ascii binary draw][:filename][:viewer format] - plots residual (not its norm) at each iteration

 56:    Level: intermediate

 58: .seealso: SNESMonitorSet(), SNESMonitorDefault(), VecView()
 59: @*/
 60: PetscErrorCode  SNESMonitorResidual(SNES snes,PetscInt its,PetscReal fgnorm,PetscViewerAndFormat *vf)
 61: {
 63:   Vec            x;
 64:   PetscViewer    viewer = vf->viewer;

 68:   SNESGetFunction(snes,&x,NULL,NULL);
 69:   PetscViewerPushFormat(viewer,vf->format);
 70:   VecView(x,viewer);
 71:   PetscViewerPopFormat(viewer);
 72:   return(0);
 73: }

 75: /*@C
 76:    SNESMonitorSolutionUpdate - Monitors progress of the SNES solvers by calling
 77:    VecView() for the UPDATE to the solution at each iteration.

 79:    Collective on SNES

 81:    Input Parameters:
 82: +  snes - the SNES context
 83: .  its - iteration number
 84: .  fgnorm - 2-norm of residual
 85: -  dummy - a viewer

 87:    Options Database Keys:
 88: .  -snes_monitor_solution_update [ascii binary draw][:filename][:viewer format] - plots update to solution at each iteration

 90:    Level: intermediate

 92: .seealso: SNESMonitorSet(), SNESMonitorDefault(), VecView()
 93: @*/
 94: PetscErrorCode  SNESMonitorSolutionUpdate(SNES snes,PetscInt its,PetscReal fgnorm,PetscViewerAndFormat *vf)
 95: {
 97:   Vec            x;
 98:   PetscViewer    viewer = vf->viewer;

102:   SNESGetSolutionUpdate(snes,&x);
103:   PetscViewerPushFormat(viewer,vf->format);
104:   VecView(x,viewer);
105:   PetscViewerPopFormat(viewer);
106:   return(0);
107: }

109: #include <petscdraw.h>

111: /*@C
112:   KSPMonitorSNESResidual - Prints the SNES residual norm, as well as the linear residual norm, at each iteration of an iterative solver.

114:   Collective on ksp

116:   Input Parameters:
117: + ksp   - iterative context
118: . n     - iteration number
119: . rnorm - 2-norm (preconditioned) residual value (may be estimated).
120: - vf    - The viewer context

122:   Options Database Key:
123: . -snes_monitor_ksp - Activates KSPMonitorSNESResidual()

125:   Level: intermediate

127: .seealso: KSPMonitorSet(), KSPMonitorResidual(),KSPMonitorTrueResidualMaxNorm()
128: @*/
129: PetscErrorCode KSPMonitorSNESResidual(KSP ksp, PetscInt n, PetscReal rnorm, PetscViewerAndFormat *vf)
130: {
131:   PetscViewer       viewer = vf->viewer;
132:   PetscViewerFormat format = vf->format;
133:   SNES              snes   = (SNES) vf->data;
134:   Vec               snes_solution, work1, work2;
135:   PetscReal         snorm;
136:   PetscInt          tablevel;
137:   const char       *prefix;
138:   PetscErrorCode    ierr;

142:   SNESGetSolution(snes, &snes_solution);
143:   VecDuplicate(snes_solution, &work1);
144:   VecDuplicate(snes_solution, &work2);
145:   KSPBuildSolution(ksp, work1, NULL);
146:   VecAYPX(work1, -1.0, snes_solution);
147:   SNESComputeFunction(snes, work1, work2);
148:   VecNorm(work2, NORM_2, &snorm);
149:   VecDestroy(&work1);
150:   VecDestroy(&work2);

152:   PetscObjectGetTabLevel((PetscObject) ksp, &tablevel);
153:   PetscObjectGetOptionsPrefix((PetscObject) ksp, &prefix);
154:   PetscViewerPushFormat(viewer, format);
155:   PetscViewerASCIIAddTab(viewer, tablevel);
156:   if (n == 0 && prefix) {PetscViewerASCIIPrintf(viewer, "  Residual norms for %s solve.\n", prefix);}
157:   PetscViewerASCIIPrintf(viewer, "%3D SNES Residual norm %5.3e KSP Residual norm %5.3e \n", n, (double) snorm, (double) rnorm);
158:   PetscViewerASCIISubtractTab(viewer, tablevel);
159:   PetscViewerPopFormat(viewer);
160:   return(0);
161: }

163: /*@C
164:   KSPMonitorSNESResidualDrawLG - Plots the linear SNES residual norm at each iteration of an iterative solver.

166:   Collective on ksp

168:   Input Parameters:
169: + ksp   - iterative context
170: . n     - iteration number
171: . rnorm - 2-norm (preconditioned) residual value (may be estimated).
172: - vf    - The viewer context

174:   Options Database Key:
175: . -snes_monitor_ksp draw::draw_lg - Activates KSPMonitorSNESResidualDrawLG()

177:   Level: intermediate

179: .seealso: KSPMonitorSet(), KSPMonitorTrueResidual()
180: @*/
181: PetscErrorCode KSPMonitorSNESResidualDrawLG(KSP ksp, PetscInt n, PetscReal rnorm, PetscViewerAndFormat *vf)
182: {
183:   PetscViewer        viewer = vf->viewer;
184:   PetscViewerFormat  format = vf->format;
185:   PetscDrawLG        lg     = vf->lg;
186:   SNES               snes   = (SNES) vf->data;
187:   Vec                snes_solution, work1, work2;
188:   PetscReal          snorm;
189:   KSPConvergedReason reason;
190:   PetscReal          x[2], y[2];
191:   PetscErrorCode     ierr;

196:   SNESGetSolution(snes, &snes_solution);
197:   VecDuplicate(snes_solution, &work1);
198:   VecDuplicate(snes_solution, &work2);
199:   KSPBuildSolution(ksp, work1, NULL);
200:   VecAYPX(work1, -1.0, snes_solution);
201:   SNESComputeFunction(snes, work1, work2);
202:   VecNorm(work2, NORM_2, &snorm);
203:   VecDestroy(&work1);
204:   VecDestroy(&work2);

206:   PetscViewerPushFormat(viewer, format);
207:   if (!n) {PetscDrawLGReset(lg);}
208:   x[0] = (PetscReal) n;
209:   if (rnorm > 0.0) y[0] = PetscLog10Real(rnorm);
210:   else y[0] = -15.0;
211:   x[1] = (PetscReal) n;
212:   if (snorm > 0.0) y[1] = PetscLog10Real(snorm);
213:   else y[1] = -15.0;
214:   PetscDrawLGAddPoint(lg, x, y);
215:   KSPGetConvergedReason(ksp, &reason);
216:   if (n <= 20 || !(n % 5) || reason) {
217:     PetscDrawLGDraw(lg);
218:     PetscDrawLGSave(lg);
219:   }
220:   PetscViewerPopFormat(viewer);
221:   return(0);
222: }

224: /*@C
225:   KSPMonitorSNESResidualDrawLGCreate - Creates the plotter for the linear SNES residual.

227:   Collective on ksp

229:   Input Parameters:
230: + viewer - The PetscViewer
231: . format - The viewer format
232: - ctx    - An optional user context

234:   Output Parameter:
235: . vf    - The viewer context

237:   Level: intermediate

239: .seealso: KSPMonitorSet(), KSPMonitorTrueResidual()
240: @*/
241: PetscErrorCode KSPMonitorSNESResidualDrawLGCreate(PetscViewer viewer, PetscViewerFormat format, void *ctx, PetscViewerAndFormat **vf)
242: {
243:   const char    *names[] = {"linear", "nonlinear"};

247:   PetscViewerAndFormatCreate(viewer, format, vf);
248:   (*vf)->data = ctx;
249:   KSPMonitorLGCreate(PetscObjectComm((PetscObject) viewer), NULL, NULL, "Log Residual Norm", 2, names, PETSC_DECIDE, PETSC_DECIDE, 400, 300, &(*vf)->lg);
250:   return(0);
251: }

253: /*@C
254:    SNESMonitorDefault - Monitors progress of the SNES solvers (default).

256:    Collective on SNES

258:    Input Parameters:
259: +  snes - the SNES context
260: .  its - iteration number
261: .  fgnorm - 2-norm of residual
262: -  vf - viewer and format structure

264:    Notes:
265:    This routine prints the residual norm at each iteration.

267:    Level: intermediate

269: .seealso: SNESMonitorSet(), SNESMonitorSolution()
270: @*/
271: PetscErrorCode  SNESMonitorDefault(SNES snes,PetscInt its,PetscReal fgnorm,PetscViewerAndFormat *vf)
272: {
273:   PetscViewer       viewer = vf->viewer;
274:   PetscViewerFormat format = vf->format;
275:   PetscBool         isascii, isdraw;
276:   PetscErrorCode    ierr;

280:   PetscObjectTypeCompare((PetscObject) viewer, PETSCVIEWERASCII, &isascii);
281:   PetscObjectTypeCompare((PetscObject) viewer, PETSCVIEWERDRAW,  &isdraw);
282:   PetscViewerPushFormat(viewer,format);
283:   if (isascii) {
284:     PetscViewerASCIIAddTab(viewer,((PetscObject)snes)->tablevel);
285:     PetscViewerASCIIPrintf(viewer,"%3D SNES Function norm %14.12e \n",its,(double)fgnorm);
286:     PetscViewerASCIISubtractTab(viewer,((PetscObject)snes)->tablevel);
287:   } else if (isdraw) {
288:     if (format == PETSC_VIEWER_DRAW_LG) {
289:       PetscDrawLG lg = (PetscDrawLG) vf->lg;
290:       PetscReal   x, y;

293:       if (!its) {PetscDrawLGReset(lg);}
294:       x = (PetscReal) its;
295:       if (fgnorm > 0.0) y = PetscLog10Real(fgnorm);
296:       else y = -15.0;
297:       PetscDrawLGAddPoint(lg,&x,&y);
298:       if (its <= 20 || !(its % 5) || snes->reason) {
299:         PetscDrawLGDraw(lg);
300:         PetscDrawLGSave(lg);
301:       }
302:     }
303:   }
304:   PetscViewerPopFormat(viewer);
305:   return(0);
306: }

308: /*@C
309:    SNESMonitorScaling - Monitors the largest value in each row of the Jacobian.

311:    Collective on SNES

313:    Input Parameters:
314: +  snes - the SNES context
315: .  its - iteration number
316: .  fgnorm - 2-norm of residual
317: -  vf - viewer and format structure

319:    Notes:
320:    This routine prints the largest value in each row of the Jacobian

322:    Level: intermediate

324: .seealso: SNESMonitorSet(), SNESMonitorSolution()
325: @*/
326: PetscErrorCode  SNESMonitorScaling(SNES snes,PetscInt its,PetscReal fgnorm,PetscViewerAndFormat *vf)
327: {
329:   PetscViewer    viewer = vf->viewer;
330:   KSP            ksp;
331:   Mat            J;
332:   Vec            v;

336:   SNESGetKSP(snes,&ksp);
337:   KSPGetOperators(ksp,&J,NULL);
338:   MatCreateVecs(J,&v,NULL);
339:   MatGetRowMaxAbs(J,v,NULL);
340:   PetscViewerPushFormat(viewer,vf->format);
341:   PetscViewerASCIIAddTab(viewer,((PetscObject)snes)->tablevel);
342:   PetscViewerASCIIPrintf(viewer,"%3D SNES Jacobian maximum row entries \n");
343:   VecView(v,viewer);
344:   PetscViewerASCIISubtractTab(viewer,((PetscObject)snes)->tablevel);
345:   PetscViewerPopFormat(viewer);
346:   VecDestroy(&v);
347:   return(0);
348: }

350: PetscErrorCode SNESMonitorJacUpdateSpectrum(SNES snes,PetscInt it,PetscReal fnorm,PetscViewerAndFormat *vf)
351: {
352:   Vec            X;
353:   Mat            J,dJ,dJdense;
355:   PetscErrorCode (*func)(SNES,Vec,Mat,Mat,void*);
356:   PetscInt       n;
357:   PetscBLASInt   nb = 0,lwork;
358:   PetscReal      *eigr,*eigi;
359:   PetscScalar    *work;
360:   PetscScalar    *a;

363:   if (it == 0) return(0);
364:   /* create the difference between the current update and the current jacobian */
365:   SNESGetSolution(snes,&X);
366:   SNESGetJacobian(snes,NULL,&J,&func,NULL);
367:   MatDuplicate(J,MAT_COPY_VALUES,&dJ);
368:   SNESComputeJacobian(snes,X,dJ,dJ);
369:   MatAXPY(dJ,-1.0,J,SAME_NONZERO_PATTERN);

371:   /* compute the spectrum directly */
372:   MatConvert(dJ,MATSEQDENSE,MAT_INITIAL_MATRIX,&dJdense);
373:   MatGetSize(dJ,&n,NULL);
374:   PetscBLASIntCast(n,&nb);
375:   lwork = 3*nb;
376:   PetscMalloc1(n,&eigr);
377:   PetscMalloc1(n,&eigi);
378:   PetscMalloc1(lwork,&work);
379:   MatDenseGetArray(dJdense,&a);
380: #if !defined(PETSC_USE_COMPLEX)
381:   {
382:     PetscBLASInt lierr;
383:     PetscInt     i;
384:     PetscFPTrapPush(PETSC_FP_TRAP_OFF);
385:     PetscStackCallBLAS("LAPACKgeev",LAPACKgeev_("N","N",&nb,a,&nb,eigr,eigi,NULL,&nb,NULL,&nb,work,&lwork,&lierr));
386:     if (lierr) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"geev() error %d",lierr);
387:     PetscFPTrapPop();
388:     PetscPrintf(PetscObjectComm((PetscObject)snes),"Eigenvalues of J_%d - J_%d:\n",it,it-1);
389:     for (i=0;i<n;i++) {
390:       PetscPrintf(PetscObjectComm((PetscObject)snes),"%5d: %20.5g + %20.5gi\n",i,(double)eigr[i],(double)eigi[i]);
391:     }
392:   }
393:   MatDenseRestoreArray(dJdense,&a);
394:   MatDestroy(&dJ);
395:   MatDestroy(&dJdense);
396:   PetscFree(eigr);
397:   PetscFree(eigi);
398:   PetscFree(work);
399:   return(0);
400: #else
401:   SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Not coded for complex");
402: #endif
403: }

405: PETSC_INTERN PetscErrorCode  SNESMonitorRange_Private(SNES,PetscInt,PetscReal*);

407: PetscErrorCode  SNESMonitorRange_Private(SNES snes,PetscInt it,PetscReal *per)
408: {
410:   Vec            resid;
411:   PetscReal      rmax,pwork;
412:   PetscInt       i,n,N;
413:   PetscScalar    *r;

416:   SNESGetFunction(snes,&resid,NULL,NULL);
417:   VecNorm(resid,NORM_INFINITY,&rmax);
418:   VecGetLocalSize(resid,&n);
419:   VecGetSize(resid,&N);
420:   VecGetArray(resid,&r);
421:   pwork = 0.0;
422:   for (i=0; i<n; i++) {
423:     pwork += (PetscAbsScalar(r[i]) > .20*rmax);
424:   }
425:   MPIU_Allreduce(&pwork,per,1,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)snes));
426:   VecRestoreArray(resid,&r);
427:   *per = *per/N;
428:   return(0);
429: }

431: /*@C
432:    SNESMonitorRange - Prints the percentage of residual elements that are more then 10 percent of the maximum value.

434:    Collective on SNES

436:    Input Parameters:
437: +  snes   - iterative context
438: .  it    - iteration number
439: .  rnorm - 2-norm (preconditioned) residual value (may be estimated).
440: -  dummy - unused monitor context

442:    Options Database Key:
443: .  -snes_monitor_range - Activates SNESMonitorRange()

445:    Level: intermediate

447: .seealso: SNESMonitorSet(), SNESMonitorDefault(), SNESMonitorLGCreate()
448: @*/
449: PetscErrorCode  SNESMonitorRange(SNES snes,PetscInt it,PetscReal rnorm,PetscViewerAndFormat *vf)
450: {
452:   PetscReal      perc,rel;
453:   PetscViewer    viewer = vf->viewer;
454:   /* should be in a MonitorRangeContext */
455:   static PetscReal prev;

459:   if (!it) prev = rnorm;
460:   SNESMonitorRange_Private(snes,it,&perc);

462:   rel  = (prev - rnorm)/prev;
463:   prev = rnorm;
464:   PetscViewerPushFormat(viewer,vf->format);
465:   PetscViewerASCIIAddTab(viewer,((PetscObject)snes)->tablevel);
466:   PetscViewerASCIIPrintf(viewer,"%3D SNES preconditioned resid norm %14.12e Percent values above 20 percent of maximum %5.2f relative decrease %5.2e ratio %5.2e \n",it,(double)rnorm,(double)(100.0*perc),(double)rel,(double)(rel/perc));
467:   PetscViewerASCIISubtractTab(viewer,((PetscObject)snes)->tablevel);
468:   PetscViewerPopFormat(viewer);
469:   return(0);
470: }

472: /*@C
473:    SNESMonitorRatio - Monitors progress of the SNES solvers by printing the ratio
474:    of residual norm at each iteration to the previous.

476:    Collective on SNES

478:    Input Parameters:
479: +  snes - the SNES context
480: .  its - iteration number
481: .  fgnorm - 2-norm of residual (or gradient)
482: -  dummy -  context of monitor

484:    Level: intermediate

486:    Notes:
487:     Insure that SNESMonitorRatio() is called when you set this monitor
488: .seealso: SNESMonitorSet(), SNESMonitorSolution(), SNESMonitorRatio()
489: @*/
490: PetscErrorCode  SNESMonitorRatio(SNES snes,PetscInt its,PetscReal fgnorm,PetscViewerAndFormat *vf)
491: {
492:   PetscErrorCode          ierr;
493:   PetscInt                len;
494:   PetscReal               *history;
495:   PetscViewer             viewer = vf->viewer;

498:   SNESGetConvergenceHistory(snes,&history,NULL,&len);
499:   PetscViewerPushFormat(viewer,vf->format);
500:   PetscViewerASCIIAddTab(viewer,((PetscObject)snes)->tablevel);
501:   if (!its || !history || its > len) {
502:     PetscViewerASCIIPrintf(viewer,"%3D SNES Function norm %14.12e \n",its,(double)fgnorm);
503:   } else {
504:     PetscReal ratio = fgnorm/history[its-1];
505:     PetscViewerASCIIPrintf(viewer,"%3D SNES Function norm %14.12e %14.12e \n",its,(double)fgnorm,(double)ratio);
506:   }
507:   PetscViewerASCIISubtractTab(viewer,((PetscObject)snes)->tablevel);
508:   PetscViewerPopFormat(viewer);
509:   return(0);
510: }

512: /*@C
513:    SNESMonitorRatioSetUp - Insures the SNES object is saving its history since this monitor needs access to it

515:    Collective on SNES

517:    Input Parameters:
518: +   snes - the SNES context
519: -   viewer - the PetscViewer object (ignored)

521:    Level: intermediate

523: .seealso: SNESMonitorSet(), SNESMonitorSolution(), SNESMonitorDefault(), SNESMonitorRatio()
524: @*/
525: PetscErrorCode  SNESMonitorRatioSetUp(SNES snes,PetscViewerAndFormat *vf)
526: {
527:   PetscErrorCode          ierr;
528:   PetscReal               *history;

531:   SNESGetConvergenceHistory(snes,&history,NULL,NULL);
532:   if (!history) {
533:     SNESSetConvergenceHistory(snes,NULL,NULL,100,PETSC_TRUE);
534:   }
535:   return(0);
536: }

538: /* ---------------------------------------------------------------- */
539: /*
540:      Default (short) SNES Monitor, same as SNESMonitorDefault() except
541:   it prints fewer digits of the residual as the residual gets smaller.
542:   This is because the later digits are meaningless and are often
543:   different on different machines; by using this routine different
544:   machines will usually generate the same output.

546:   Deprecated: Intentionally has no manual page
547: */
548: PetscErrorCode  SNESMonitorDefaultShort(SNES snes,PetscInt its,PetscReal fgnorm,PetscViewerAndFormat *vf)
549: {
551:   PetscViewer    viewer = vf->viewer;

555:   PetscViewerPushFormat(viewer,vf->format);
556:   PetscViewerASCIIAddTab(viewer,((PetscObject)snes)->tablevel);
557:   if (fgnorm > 1.e-9) {
558:     PetscViewerASCIIPrintf(viewer,"%3D SNES Function norm %g \n",its,(double)fgnorm);
559:   } else if (fgnorm > 1.e-11) {
560:     PetscViewerASCIIPrintf(viewer,"%3D SNES Function norm %5.3e \n",its,(double)fgnorm);
561:   } else {
562:     PetscViewerASCIIPrintf(viewer,"%3D SNES Function norm < 1.e-11\n",its);
563:   }
564:   PetscViewerASCIISubtractTab(viewer,((PetscObject)snes)->tablevel);
565:   PetscViewerPopFormat(viewer);
566:   return(0);
567: }

569: /*@C
570:   SNESMonitorDefaultField - Monitors progress of the SNES solvers, separated into fields.

572:   Collective on SNES

574:   Input Parameters:
575: + snes   - the SNES context
576: . its    - iteration number
577: . fgnorm - 2-norm of residual
578: - ctx    - the PetscViewer

580:   Notes:
581:   This routine uses the DM attached to the residual vector

583:   Level: intermediate

585: .seealso: SNESMonitorSet(), SNESMonitorSolution(), SNESMonitorDefault()
586: @*/
587: PetscErrorCode SNESMonitorDefaultField(SNES snes, PetscInt its, PetscReal fgnorm, PetscViewerAndFormat *vf)
588: {
589:   PetscViewer    viewer = vf->viewer;
590:   Vec            r;
591:   DM             dm;
592:   PetscReal      res[256];
593:   PetscInt       tablevel;

598:   SNESGetFunction(snes, &r, NULL, NULL);
599:   VecGetDM(r, &dm);
600:   if (!dm) {SNESMonitorDefault(snes, its, fgnorm, vf);}
601:   else {
602:     PetscSection s, gs;
603:     PetscInt     Nf, f;

605:     DMGetLocalSection(dm, &s);
606:     DMGetGlobalSection(dm, &gs);
607:     if (!s || !gs) {SNESMonitorDefault(snes, its, fgnorm, vf);}
608:     PetscSectionGetNumFields(s, &Nf);
609:     if (Nf > 256) SETERRQ1(PetscObjectComm((PetscObject) snes), PETSC_ERR_SUP, "Do not support %d fields > 256", Nf);
610:     PetscSectionVecNorm(s, gs, r, NORM_2, res);
611:     PetscObjectGetTabLevel((PetscObject) snes, &tablevel);
612:     PetscViewerPushFormat(viewer,vf->format);
613:     PetscViewerASCIIAddTab(viewer, tablevel);
614:     PetscViewerASCIIPrintf(viewer, "%3D SNES Function norm %14.12e [", its, (double) fgnorm);
615:     for (f = 0; f < Nf; ++f) {
616:       if (f) {PetscViewerASCIIPrintf(viewer, ", ");}
617:       PetscViewerASCIIPrintf(viewer, "%14.12e", res[f]);
618:     }
619:     PetscViewerASCIIPrintf(viewer, "] \n");
620:     PetscViewerASCIISubtractTab(viewer, tablevel);
621:     PetscViewerPopFormat(viewer);
622:   }
623:   return(0);
624: }
625: /* ---------------------------------------------------------------- */
626: /*@C
627:    SNESConvergedDefault - Default onvergence test of the solvers for
628:    systems of nonlinear equations.

630:    Collective on SNES

632:    Input Parameters:
633: +  snes - the SNES context
634: .  it - the iteration (0 indicates before any Newton steps)
635: .  xnorm - 2-norm of current iterate
636: .  snorm - 2-norm of current step
637: .  fnorm - 2-norm of function at current iterate
638: -  dummy - unused context

640:    Output Parameter:
641: .   reason  - one of
642: $  SNES_CONVERGED_FNORM_ABS       - (fnorm < abstol),
643: $  SNES_CONVERGED_SNORM_RELATIVE  - (snorm < stol*xnorm),
644: $  SNES_CONVERGED_FNORM_RELATIVE  - (fnorm < rtol*fnorm0),
645: $  SNES_DIVERGED_FUNCTION_COUNT   - (nfct > maxf),
646: $  SNES_DIVERGED_FNORM_NAN        - (fnorm == NaN),
647: $  SNES_CONVERGED_ITERATING       - (otherwise),
648: $  SNES_DIVERGED_DTOL             - (fnorm > divtol*snes->fnorm0)

650:    where
651: +    maxf - maximum number of function evaluations,  set with SNESSetTolerances()
652: .    nfct - number of function evaluations,
653: .    abstol - absolute function norm tolerance, set with SNESSetTolerances()
654: .    rtol - relative function norm tolerance, set with SNESSetTolerances()
655: .    divtol - divergence tolerance, set with SNESSetDivergenceTolerance()
656: -    fnorm0 - 2-norm of the function at the initial solution (initial guess; zeroth iteration)

658:   Options Database Keys:
659: +  -snes_stol - convergence tolerance in terms of the norm  of the change in the solution between steps
660: .  -snes_atol <abstol> - absolute tolerance of residual norm
661: .  -snes_rtol <rtol> - relative decrease in tolerance norm from the initial 2-norm of the solution
662: .  -snes_divergence_tolerance <divtol> - if the residual goes above divtol*rnorm0, exit with divergence
663: .  -snes_max_funcs <max_funcs> - maximum number of function evaluations
664: .  -snes_max_fail <max_fail> - maximum number of line search failures allowed before stopping, default is none
665: -  -snes_max_linear_solve_fail - number of linear solver failures before SNESSolve() stops

667:    Level: intermediate

669: .seealso: SNESSetConvergenceTest(), SNESConvergedSkip(), SNESSetTolerances(), SNESSetDivergenceTolerance()
670: @*/
671: PetscErrorCode  SNESConvergedDefault(SNES snes,PetscInt it,PetscReal xnorm,PetscReal snorm,PetscReal fnorm,SNESConvergedReason *reason,void *dummy)
672: {


679:   *reason = SNES_CONVERGED_ITERATING;

681:   if (!it) {
682:     /* set parameter for default relative tolerance convergence test */
683:     snes->ttol   = fnorm*snes->rtol;
684:     snes->rnorm0 = fnorm;
685:   }
686:   if (PetscIsInfOrNanReal(fnorm)) {
687:     PetscInfo(snes,"Failed to converged, function norm is NaN\n");
688:     *reason = SNES_DIVERGED_FNORM_NAN;
689:   } else if (fnorm < snes->abstol && (it || !snes->forceiteration)) {
690:     PetscInfo2(snes,"Converged due to function norm %14.12e < %14.12e\n",(double)fnorm,(double)snes->abstol);
691:     *reason = SNES_CONVERGED_FNORM_ABS;
692:   } else if (snes->nfuncs >= snes->max_funcs && snes->max_funcs >= 0) {
693:     PetscInfo2(snes,"Exceeded maximum number of function evaluations: %D > %D\n",snes->nfuncs,snes->max_funcs);
694:     *reason = SNES_DIVERGED_FUNCTION_COUNT;
695:   }

697:   if (it && !*reason) {
698:     if (fnorm <= snes->ttol) {
699:       PetscInfo2(snes,"Converged due to function norm %14.12e < %14.12e (relative tolerance)\n",(double)fnorm,(double)snes->ttol);
700:       *reason = SNES_CONVERGED_FNORM_RELATIVE;
701:     } else if (snorm < snes->stol*xnorm) {
702:       PetscInfo3(snes,"Converged due to small update length: %14.12e < %14.12e * %14.12e\n",(double)snorm,(double)snes->stol,(double)xnorm);
703:       *reason = SNES_CONVERGED_SNORM_RELATIVE;
704:     } else if (snes->divtol > 0 && (fnorm > snes->divtol*snes->rnorm0)) {
705:       PetscInfo3(snes,"Diverged due to increase in function norm: %14.12e > %14.12e * %14.12e\n",(double)fnorm,(double)snes->divtol,(double)snes->rnorm0);
706:       *reason = SNES_DIVERGED_DTOL;
707:     }

709:   }
710:   return(0);
711: }

713: /*@C
714:    SNESConvergedSkip - Convergence test for SNES that NEVER returns as
715:    converged, UNLESS the maximum number of iteration have been reached.

717:    Logically Collective on SNES

719:    Input Parameters:
720: +  snes - the SNES context
721: .  it - the iteration (0 indicates before any Newton steps)
722: .  xnorm - 2-norm of current iterate
723: .  snorm - 2-norm of current step
724: .  fnorm - 2-norm of function at current iterate
725: -  dummy - unused context

727:    Output Parameter:
728: .   reason  - SNES_CONVERGED_ITERATING, SNES_CONVERGED_ITS, or SNES_DIVERGED_FNORM_NAN

730:    Notes:
731:    Convergence is then declared after a fixed number of iterations have been used.

733:    Level: advanced

735: .seealso: SNESConvergedDefault(), SNESSetConvergenceTest()
736: @*/
737: PetscErrorCode  SNESConvergedSkip(SNES snes,PetscInt it,PetscReal xnorm,PetscReal snorm,PetscReal fnorm,SNESConvergedReason *reason,void *dummy)
738: {


745:   *reason = SNES_CONVERGED_ITERATING;

747:   if (fnorm != fnorm) {
748:     PetscInfo(snes,"Failed to converged, function norm is NaN\n");
749:     *reason = SNES_DIVERGED_FNORM_NAN;
750:   } else if (it == snes->max_its) {
751:     *reason = SNES_CONVERGED_ITS;
752:   }
753:   return(0);
754: }

756: /*@C
757:   SNESSetWorkVecs - Gets a number of work vectors.

759:   Input Parameters:
760: + snes  - the SNES context
761: - nw - number of work vectors to allocate

763:   Level: developer

765: @*/
766: PetscErrorCode SNESSetWorkVecs(SNES snes,PetscInt nw)
767: {
768:   DM             dm;
769:   Vec            v;

773:   if (snes->work) {VecDestroyVecs(snes->nwork,&snes->work);}
774:   snes->nwork = nw;

776:   SNESGetDM(snes, &dm);
777:   DMGetGlobalVector(dm, &v);
778:   VecDuplicateVecs(v,snes->nwork,&snes->work);
779:   DMRestoreGlobalVector(dm, &v);
780:   PetscLogObjectParents(snes,nw,snes->work);
781:   return(0);
782: }