Actual source code: virs.c

petsc-master 2018-12-12
Report Typos and Errors

  2:  #include <../src/snes/impls/vi/rs/virsimpl.h>
  3:  #include <petsc/private/dmimpl.h>
  4:  #include <petsc/private/vecimpl.h>

  6: /*
  7:    SNESVIGetInactiveSet - Gets the global indices for the inactive set variables (these correspond to the degrees of freedom the linear
  8:      system is solved on)

 10:    Input parameter
 11: .  snes - the SNES context

 13:    Output parameter
 14: .  inact - inactive set index set

 16:  */
 17: PetscErrorCode SNESVIGetInactiveSet(SNES snes,IS *inact)
 18: {
 19:   SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS*)snes->data;

 22:   *inact = vi->IS_inact;
 23:   return(0);
 24: }

 26: /*
 27:     Provides a wrapper to a DM to allow it to be used to generated the interpolation/restriction from the DM for the smaller matrices and vectors
 28:   defined by the reduced space method.

 30:     Simple calls the regular DM interpolation and restricts it to operation on the variables not associated with active constraints.

 32: <*/
 33: typedef struct {
 34:   PetscInt n;                                              /* size of vectors in the reduced DM space */
 35:   IS       inactive;

 37:   PetscErrorCode (*createinterpolation)(DM,DM,Mat*,Vec*);  /* DM's original routines */
 38:   PetscErrorCode (*coarsen)(DM, MPI_Comm, DM*);
 39:   PetscErrorCode (*createglobalvector)(DM,Vec*);
 40:   PetscErrorCode (*getinjection)(DM,DM,Mat*);
 41:   PetscErrorCode (*hascreateinjection)(DM,PetscBool*);

 43:   DM dm;                                                  /* when destroying this object we need to reset the above function into the base DM */
 44: } DM_SNESVI;

 46: /*
 47:      DMCreateGlobalVector_SNESVI - Creates global vector of the size of the reduced space

 49: */
 50: PetscErrorCode  DMCreateGlobalVector_SNESVI(DM dm,Vec *vec)
 51: {
 53:   PetscContainer isnes;
 54:   DM_SNESVI      *dmsnesvi;

 57:   PetscObjectQuery((PetscObject)dm,"VI",(PetscObject*)&isnes);
 58:   if (!isnes) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_PLIB,"Composed SNES is missing");
 59:   PetscContainerGetPointer(isnes,(void**)&dmsnesvi);
 60:   VecCreateMPI(PetscObjectComm((PetscObject)dm),dmsnesvi->n,PETSC_DETERMINE,vec);
 61:   return(0);
 62: }

 64: static PetscErrorCode DMHasCreateInjection_SNESVI(DM dm, PetscBool *flg)
 65: {
 69:   *flg = PETSC_FALSE;
 70:   return(0);
 71: }

 73: /*
 74:      DMCreateInterpolation_SNESVI - Modifieds the interpolation obtained from the DM by removing all rows and columns associated with active constraints.

 76: */
 77: PetscErrorCode  DMCreateInterpolation_SNESVI(DM dm1,DM dm2,Mat *mat,Vec *vec)
 78: {
 80:   PetscContainer isnes;
 81:   DM_SNESVI      *dmsnesvi1,*dmsnesvi2;
 82:   Mat            interp;

 85:   PetscObjectQuery((PetscObject)dm1,"VI",(PetscObject*)&isnes);
 86:   if (!isnes) SETERRQ(PetscObjectComm((PetscObject)dm1),PETSC_ERR_PLIB,"Composed VI data structure is missing");
 87:   PetscContainerGetPointer(isnes,(void**)&dmsnesvi1);
 88:   PetscObjectQuery((PetscObject)dm2,"VI",(PetscObject*)&isnes);
 89:   if (!isnes) SETERRQ(PetscObjectComm((PetscObject)dm2),PETSC_ERR_PLIB,"Composed VI data structure is missing");
 90:   PetscContainerGetPointer(isnes,(void**)&dmsnesvi2);

 92:   (*dmsnesvi1->createinterpolation)(dm1,dm2,&interp,NULL);
 93:   MatCreateSubMatrix(interp,dmsnesvi2->inactive,dmsnesvi1->inactive,MAT_INITIAL_MATRIX,mat);
 94:   MatDestroy(&interp);
 95:   *vec = 0;
 96:   return(0);
 97: }

 99: static PetscErrorCode DMSetVI(DM,IS);
100: static PetscErrorCode DMDestroyVI(DM);

102: /*
103:      DMCoarsen_SNESVI - Computes the regular coarsened DM then computes additional information about its inactive set

105: */
106: PetscErrorCode  DMCoarsen_SNESVI(DM dm1,MPI_Comm comm,DM *dm2)
107: {
109:   PetscContainer isnes;
110:   DM_SNESVI      *dmsnesvi1;
111:   Vec            finemarked,coarsemarked;
112:   IS             inactive;
113:   Mat            inject;
114:   const PetscInt *index;
115:   PetscInt       n,k,cnt = 0,rstart,*coarseindex;
116:   PetscScalar    *marked;

119:   PetscObjectQuery((PetscObject)dm1,"VI",(PetscObject*)&isnes);
120:   if (!isnes) SETERRQ(PetscObjectComm((PetscObject)dm1),PETSC_ERR_PLIB,"Composed VI data structure is missing");
121:   PetscContainerGetPointer(isnes,(void**)&dmsnesvi1);

123:   /* get the original coarsen */
124:   (*dmsnesvi1->coarsen)(dm1,comm,dm2);

126:   /* not sure why this extra reference is needed, but without the dm2 disappears too early */
127:   /* Updating the KSPCreateVecs() to avoid using DMGetGlobalVector() when matrix is available removes the need for this reference? */
128:   /*  PetscObjectReference((PetscObject)*dm2);*/

130:   /* need to set back global vectors in order to use the original injection */
131:   DMClearGlobalVectors(dm1);

133:   dm1->ops->createglobalvector = dmsnesvi1->createglobalvector;

135:   DMCreateGlobalVector(dm1,&finemarked);
136:   DMCreateGlobalVector(*dm2,&coarsemarked);

138:   /*
139:      fill finemarked with locations of inactive points
140:   */
141:   ISGetIndices(dmsnesvi1->inactive,&index);
142:   ISGetLocalSize(dmsnesvi1->inactive,&n);
143:   VecSet(finemarked,0.0);
144:   for (k=0; k<n; k++) {
145:     VecSetValue(finemarked,index[k],1.0,INSERT_VALUES);
146:   }
147:   VecAssemblyBegin(finemarked);
148:   VecAssemblyEnd(finemarked);

150:   DMCreateInjection(*dm2,dm1,&inject);
151:   MatRestrict(inject,finemarked,coarsemarked);
152:   MatDestroy(&inject);

154:   /*
155:      create index set list of coarse inactive points from coarsemarked
156:   */
157:   VecGetLocalSize(coarsemarked,&n);
158:   VecGetOwnershipRange(coarsemarked,&rstart,NULL);
159:   VecGetArray(coarsemarked,&marked);
160:   for (k=0; k<n; k++) {
161:     if (marked[k] != 0.0) cnt++;
162:   }
163:   PetscMalloc1(cnt,&coarseindex);
164:   cnt  = 0;
165:   for (k=0; k<n; k++) {
166:     if (marked[k] != 0.0) coarseindex[cnt++] = k + rstart;
167:   }
168:   VecRestoreArray(coarsemarked,&marked);
169:   ISCreateGeneral(PetscObjectComm((PetscObject)coarsemarked),cnt,coarseindex,PETSC_OWN_POINTER,&inactive);

171:   DMClearGlobalVectors(dm1);

173:   dm1->ops->createglobalvector = DMCreateGlobalVector_SNESVI;

175:   DMSetVI(*dm2,inactive);

177:   VecDestroy(&finemarked);
178:   VecDestroy(&coarsemarked);
179:   ISDestroy(&inactive);
180:   return(0);
181: }

183: PetscErrorCode DMDestroy_SNESVI(DM_SNESVI *dmsnesvi)
184: {

188:   /* reset the base methods in the DM object that were changed when the DM_SNESVI was reset */
189:   dmsnesvi->dm->ops->createinterpolation = dmsnesvi->createinterpolation;
190:   dmsnesvi->dm->ops->coarsen             = dmsnesvi->coarsen;
191:   dmsnesvi->dm->ops->createglobalvector  = dmsnesvi->createglobalvector;
192:   dmsnesvi->dm->ops->getinjection        = dmsnesvi->getinjection;
193:   dmsnesvi->dm->ops->hascreateinjection  = dmsnesvi->hascreateinjection;
194:   /* need to clear out this vectors because some of them may not have a reference to the DM
195:     but they are counted as having references to the DM in DMDestroy() */
196:   DMClearGlobalVectors(dmsnesvi->dm);

198:   ISDestroy(&dmsnesvi->inactive);
199:   PetscFree(dmsnesvi);
200:   return(0);
201: }

203: /*
204:      DMSetVI - Marks a DM as associated with a VI problem. This causes the interpolation/restriction operators to
205:                be restricted to only those variables NOT associated with active constraints.

207: */
208: static PetscErrorCode DMSetVI(DM dm,IS inactive)
209: {
211:   PetscContainer isnes;
212:   DM_SNESVI      *dmsnesvi;

215:   if (!dm) return(0);

217:   PetscObjectReference((PetscObject)inactive);

219:   PetscObjectQuery((PetscObject)dm,"VI",(PetscObject*)&isnes);
220:   if (!isnes) {
221:     PetscContainerCreate(PetscObjectComm((PetscObject)dm),&isnes);
222:     PetscContainerSetUserDestroy(isnes,(PetscErrorCode (*)(void*))DMDestroy_SNESVI);
223:     PetscNew(&dmsnesvi);
224:     PetscContainerSetPointer(isnes,(void*)dmsnesvi);
225:     PetscObjectCompose((PetscObject)dm,"VI",(PetscObject)isnes);
226:     PetscContainerDestroy(&isnes);

228:     dmsnesvi->createinterpolation = dm->ops->createinterpolation;
229:     dm->ops->createinterpolation  = DMCreateInterpolation_SNESVI;
230:     dmsnesvi->coarsen             = dm->ops->coarsen;
231:     dm->ops->coarsen              = DMCoarsen_SNESVI;
232:     dmsnesvi->createglobalvector  = dm->ops->createglobalvector;
233:     dm->ops->createglobalvector   = DMCreateGlobalVector_SNESVI;
234:     dmsnesvi->getinjection        = dm->ops->getinjection;
235:     dm->ops->getinjection         = NULL;
236:     dmsnesvi->hascreateinjection  = dm->ops->hascreateinjection;
237:     dm->ops->hascreateinjection   = DMHasCreateInjection_SNESVI;
238:   } else {
239:     PetscContainerGetPointer(isnes,(void**)&dmsnesvi);
240:     ISDestroy(&dmsnesvi->inactive);
241:   }
242:   DMClearGlobalVectors(dm);
243:   ISGetLocalSize(inactive,&dmsnesvi->n);

245:   dmsnesvi->inactive = inactive;
246:   dmsnesvi->dm       = dm;
247:   return(0);
248: }

250: /*
251:      DMDestroyVI - Frees the DM_SNESVI object contained in the DM
252:          - also resets the function pointers in the DM for createinterpolation() etc to use the original DM
253: */
254: static PetscErrorCode DMDestroyVI(DM dm)
255: {

259:   if (!dm) return(0);
260:   PetscObjectCompose((PetscObject)dm,"VI",(PetscObject)NULL);
261:   return(0);
262: }

264: /* --------------------------------------------------------------------------------------------------------*/


267: PetscErrorCode SNESCreateIndexSets_VINEWTONRSLS(SNES snes,Vec X,Vec F,IS *ISact,IS *ISinact)
268: {

272:   SNESVIGetActiveSetIS(snes,X,F,ISact);
273:   ISComplement(*ISact,X->map->rstart,X->map->rend,ISinact);
274:   return(0);
275: }

277: /* Create active and inactive set vectors. The local size of this vector is set and petsc computes the global size */
278: PetscErrorCode SNESCreateSubVectors_VINEWTONRSLS(SNES snes,PetscInt n,Vec *newv)
279: {
281:   Vec            v;

284:   VecCreate(PetscObjectComm((PetscObject)snes),&v);
285:   VecSetSizes(v,n,PETSC_DECIDE);
286:   VecSetType(v,VECSTANDARD);
287:   *newv = v;
288:   return(0);
289: }

291: /* Resets the snes PC and KSP when the active set sizes change */
292: PetscErrorCode SNESVIResetPCandKSP(SNES snes,Mat Amat,Mat Pmat)
293: {
295:   KSP            snesksp;

298:   SNESGetKSP(snes,&snesksp);
299:   KSPReset(snesksp);
300:   KSPResetFromOptions(snesksp);

302:   /*
303:   KSP                    kspnew;
304:   PC                     pcnew;
305:   MatSolverType          stype;


308:   KSPCreate(PetscObjectComm((PetscObject)snes),&kspnew);
309:   kspnew->pc_side = snesksp->pc_side;
310:   kspnew->rtol    = snesksp->rtol;
311:   kspnew->abstol    = snesksp->abstol;
312:   kspnew->max_it  = snesksp->max_it;
313:   KSPSetType(kspnew,((PetscObject)snesksp)->type_name);
314:   KSPGetPC(kspnew,&pcnew);
315:   PCSetType(kspnew->pc,((PetscObject)snesksp->pc)->type_name);
316:   PCSetOperators(kspnew->pc,Amat,Pmat);
317:   PCFactorGetMatSolverType(snesksp->pc,&stype);
318:   PCFactorSetMatSolverType(kspnew->pc,stype);
319:   KSPDestroy(&snesksp);
320:   snes->ksp = kspnew;
321:   PetscLogObjectParent((PetscObject)snes,(PetscObject)kspnew);
322:    KSPSetFromOptions(kspnew);*/
323:   return(0);
324: }

326: /* Variational Inequality solver using reduce space method. No semismooth algorithm is
327:    implemented in this algorithm. It basically identifies the active constraints and does
328:    a linear solve on the other variables (those not associated with the active constraints). */
329: PetscErrorCode SNESSolve_VINEWTONRSLS(SNES snes)
330: {
331:   SNES_VINEWTONRSLS    *vi = (SNES_VINEWTONRSLS*)snes->data;
332:   PetscErrorCode       ierr;
333:   PetscInt             maxits,i,lits;
334:   SNESLineSearchReason lssucceed;
335:   PetscReal            fnorm,gnorm,xnorm=0,ynorm;
336:   Vec                  Y,X,F;
337:   KSPConvergedReason   kspreason;
338:   KSP                  ksp;
339:   PC                   pc;

342:   /* Multigrid must use Galerkin for coarse grids with active set/reduced space methods; cannot rediscretize on coarser grids*/
343:   SNESGetKSP(snes,&ksp);
344:   KSPGetPC(ksp,&pc);
345:   PCMGSetGalerkin(pc,PC_MG_GALERKIN_BOTH);

347:   snes->numFailures            = 0;
348:   snes->numLinearSolveFailures = 0;
349:   snes->reason                 = SNES_CONVERGED_ITERATING;

351:   maxits = snes->max_its;               /* maximum number of iterations */
352:   X      = snes->vec_sol;               /* solution vector */
353:   F      = snes->vec_func;              /* residual vector */
354:   Y      = snes->work[0];               /* work vectors */

356:   SNESLineSearchSetVIFunctions(snes->linesearch, SNESVIProjectOntoBounds, SNESVIComputeInactiveSetFnorm);
357:   SNESLineSearchSetVecs(snes->linesearch, X, NULL, NULL, NULL, NULL);
358:   SNESLineSearchSetUp(snes->linesearch);

360:   PetscObjectSAWsTakeAccess((PetscObject)snes);
361:   snes->iter = 0;
362:   snes->norm = 0.0;
363:   PetscObjectSAWsGrantAccess((PetscObject)snes);

365:   SNESVIProjectOntoBounds(snes,X);
366:   SNESComputeFunction(snes,X,F);
367:   SNESVIComputeInactiveSetFnorm(snes,F,X,&fnorm);
368:   VecNorm(X,NORM_2,&xnorm);        /* xnorm <- ||x||  */
369:   SNESCheckFunctionNorm(snes,fnorm);
370:   PetscObjectSAWsTakeAccess((PetscObject)snes);
371:   snes->norm = fnorm;
372:   PetscObjectSAWsGrantAccess((PetscObject)snes);
373:   SNESLogConvergenceHistory(snes,fnorm,0);
374:   SNESMonitor(snes,0,fnorm);

376:   /* test convergence */
377:   (*snes->ops->converged)(snes,0,0.0,0.0,fnorm,&snes->reason,snes->cnvP);
378:   if (snes->reason) return(0);


381:   for (i=0; i<maxits; i++) {

383:     IS         IS_act; /* _act -> active set _inact -> inactive set */
384:     IS         IS_redact; /* redundant active set */
385:     VecScatter scat_act,scat_inact;
386:     PetscInt   nis_act,nis_inact;
387:     Vec        Y_act,Y_inact,F_inact;
388:     Mat        jac_inact_inact,prejac_inact_inact;
389:     PetscBool  isequal;

391:     /* Call general purpose update function */
392:     if (snes->ops->update) {
393:       (*snes->ops->update)(snes, snes->iter);
394:     }
395:     SNESComputeJacobian(snes,X,snes->jacobian,snes->jacobian_pre);


398:     /* Create active and inactive index sets */

400:     /*original
401:     SNESVICreateIndexSets_RS(snes,X,F,&IS_act,&vi->IS_inact);
402:      */
403:     SNESVIGetActiveSetIS(snes,X,F,&IS_act);

405:     if (vi->checkredundancy) {
406:       (*vi->checkredundancy)(snes,IS_act,&IS_redact,vi->ctxP);
407:       if (IS_redact) {
408:         ISSort(IS_redact);
409:         ISComplement(IS_redact,X->map->rstart,X->map->rend,&vi->IS_inact);
410:         ISDestroy(&IS_redact);
411:       } else {
412:         ISComplement(IS_act,X->map->rstart,X->map->rend,&vi->IS_inact);
413:       }
414:     } else {
415:       ISComplement(IS_act,X->map->rstart,X->map->rend,&vi->IS_inact);
416:     }


419:     /* Create inactive set submatrix */
420:     MatCreateSubMatrix(snes->jacobian,vi->IS_inact,vi->IS_inact,MAT_INITIAL_MATRIX,&jac_inact_inact);

422:     if (0) {                    /* Dead code (temporary developer hack) */
423:       IS keptrows;
424:       MatFindNonzeroRows(jac_inact_inact,&keptrows);
425:       if (keptrows) {
426:         PetscInt       cnt,*nrows,k;
427:         const PetscInt *krows,*inact;
428:         PetscInt       rstart;

430:         MatGetOwnershipRange(jac_inact_inact,&rstart,NULL);
431:         MatDestroy(&jac_inact_inact);
432:         ISDestroy(&IS_act);

434:         ISGetLocalSize(keptrows,&cnt);
435:         ISGetIndices(keptrows,&krows);
436:         ISGetIndices(vi->IS_inact,&inact);
437:         PetscMalloc1(cnt,&nrows);
438:         for (k=0; k<cnt; k++) nrows[k] = inact[krows[k]-rstart];
439:         ISRestoreIndices(keptrows,&krows);
440:         ISRestoreIndices(vi->IS_inact,&inact);
441:         ISDestroy(&keptrows);
442:         ISDestroy(&vi->IS_inact);

444:         ISCreateGeneral(PetscObjectComm((PetscObject)snes),cnt,nrows,PETSC_OWN_POINTER,&vi->IS_inact);
445:         ISComplement(vi->IS_inact,F->map->rstart,F->map->rend,&IS_act);
446:         MatCreateSubMatrix(snes->jacobian,vi->IS_inact,vi->IS_inact,MAT_INITIAL_MATRIX,&jac_inact_inact);
447:       }
448:     }
449:     DMSetVI(snes->dm,vi->IS_inact);
450:     /* remove later */

452:     /*
453:     VecView(vi->xu,PETSC_VIEWER_BINARY_(((PetscObject)(vi->xu))->comm));
454:     VecView(vi->xl,PETSC_VIEWER_BINARY_(((PetscObject)(vi->xl))->comm));
455:     VecView(X,PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)X)));
456:     VecView(F,PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)F)));
457:     ISView(vi->IS_inact,PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)vi->IS_inact)));
458:      */

460:     /* Get sizes of active and inactive sets */
461:     ISGetLocalSize(IS_act,&nis_act);
462:     ISGetLocalSize(vi->IS_inact,&nis_inact);

464:     /* Create active and inactive set vectors */
465:     SNESCreateSubVectors_VINEWTONRSLS(snes,nis_inact,&F_inact);
466:     SNESCreateSubVectors_VINEWTONRSLS(snes,nis_act,&Y_act);
467:     SNESCreateSubVectors_VINEWTONRSLS(snes,nis_inact,&Y_inact);

469:     /* Create scatter contexts */
470:     VecScatterCreateWithData(Y,IS_act,Y_act,NULL,&scat_act);
471:     VecScatterCreateWithData(Y,vi->IS_inact,Y_inact,NULL,&scat_inact);

473:     /* Do a vec scatter to active and inactive set vectors */
474:     VecScatterBegin(scat_inact,F,F_inact,INSERT_VALUES,SCATTER_FORWARD);
475:     VecScatterEnd(scat_inact,F,F_inact,INSERT_VALUES,SCATTER_FORWARD);

477:     VecScatterBegin(scat_act,Y,Y_act,INSERT_VALUES,SCATTER_FORWARD);
478:     VecScatterEnd(scat_act,Y,Y_act,INSERT_VALUES,SCATTER_FORWARD);

480:     VecScatterBegin(scat_inact,Y,Y_inact,INSERT_VALUES,SCATTER_FORWARD);
481:     VecScatterEnd(scat_inact,Y,Y_inact,INSERT_VALUES,SCATTER_FORWARD);

483:     /* Active set direction = 0 */
484:     VecSet(Y_act,0);
485:     if (snes->jacobian != snes->jacobian_pre) {
486:       MatCreateSubMatrix(snes->jacobian_pre,vi->IS_inact,vi->IS_inact,MAT_INITIAL_MATRIX,&prejac_inact_inact);
487:     } else prejac_inact_inact = jac_inact_inact;

489:     ISEqual(vi->IS_inact_prev,vi->IS_inact,&isequal);
490:     if (!isequal) {
491:       SNESVIResetPCandKSP(snes,jac_inact_inact,prejac_inact_inact);
492:       PCFieldSplitRestrictIS(pc,vi->IS_inact);
493:     }

495:     /*      ISView(vi->IS_inact,0); */
496:     /*      ISView(IS_act,0);*/
497:     /*      MatView(snes->jacobian_pre,0); */



501:     KSPSetOperators(snes->ksp,jac_inact_inact,prejac_inact_inact);
502:     KSPSetUp(snes->ksp);
503:     {
504:       PC        pc;
505:       PetscBool flg;
506:       KSPGetPC(snes->ksp,&pc);
507:       PetscObjectTypeCompare((PetscObject)pc,PCFIELDSPLIT,&flg);
508:       if (flg) {
509:         KSP *subksps;
510:         PCFieldSplitGetSubKSP(pc,NULL,&subksps);
511:         KSPGetPC(subksps[0],&pc);
512:         PetscFree(subksps);
513:         PetscObjectTypeCompare((PetscObject)pc,PCBJACOBI,&flg);
514:         if (flg) {
515:           PetscInt       n,N = 101*101,j,cnts[3] = {0,0,0};
516:           const PetscInt *ii;

518:           ISGetSize(vi->IS_inact,&n);
519:           ISGetIndices(vi->IS_inact,&ii);
520:           for (j=0; j<n; j++) {
521:             if (ii[j] < N) cnts[0]++;
522:             else if (ii[j] < 2*N) cnts[1]++;
523:             else if (ii[j] < 3*N) cnts[2]++;
524:           }
525:           ISRestoreIndices(vi->IS_inact,&ii);

527:           PCBJacobiSetTotalBlocks(pc,3,cnts);
528:         }
529:       }
530:     }

532:     KSPSolve(snes->ksp,F_inact,Y_inact);
533:     VecScatterBegin(scat_act,Y_act,Y,INSERT_VALUES,SCATTER_REVERSE);
534:     VecScatterEnd(scat_act,Y_act,Y,INSERT_VALUES,SCATTER_REVERSE);
535:     VecScatterBegin(scat_inact,Y_inact,Y,INSERT_VALUES,SCATTER_REVERSE);
536:     VecScatterEnd(scat_inact,Y_inact,Y,INSERT_VALUES,SCATTER_REVERSE);

538:     VecDestroy(&F_inact);
539:     VecDestroy(&Y_act);
540:     VecDestroy(&Y_inact);
541:     VecScatterDestroy(&scat_act);
542:     VecScatterDestroy(&scat_inact);
543:     ISDestroy(&IS_act);
544:     if (!isequal) {
545:       ISDestroy(&vi->IS_inact_prev);
546:       ISDuplicate(vi->IS_inact,&vi->IS_inact_prev);
547:     }
548:     ISDestroy(&vi->IS_inact);
549:     MatDestroy(&jac_inact_inact);
550:     if (snes->jacobian != snes->jacobian_pre) {
551:       MatDestroy(&prejac_inact_inact);
552:     }

554:     KSPGetConvergedReason(snes->ksp,&kspreason);
555:     if (kspreason < 0) {
556:       if (++snes->numLinearSolveFailures >= snes->maxLinearSolveFailures) {
557:         PetscInfo2(snes,"iter=%D, number linear solve failures %D greater than current SNES allowed, stopping solve\n",snes->iter,snes->numLinearSolveFailures);
558:         snes->reason = SNES_DIVERGED_LINEAR_SOLVE;
559:         break;
560:       }
561:     }

563:     KSPGetIterationNumber(snes->ksp,&lits);
564:     snes->linear_its += lits;
565:     PetscInfo2(snes,"iter=%D, linear solve iterations=%D\n",snes->iter,lits);
566:     /*
567:     if (snes->ops->precheck) {
568:       PetscBool changed_y = PETSC_FALSE;
569:       (*snes->ops->precheck)(snes,X,Y,snes->precheck,&changed_y);
570:     }

572:     if (PetscLogPrintInfo) {
573:       SNESVICheckResidual_Private(snes,snes->jacobian,F,Y,G,W);
574:     }
575:     */
576:     /* Compute a (scaled) negative update in the line search routine:
577:          Y <- X - lambda*Y
578:        and evaluate G = function(Y) (depends on the line search).
579:     */
580:     VecCopy(Y,snes->vec_sol_update);
581:     ynorm = 1; gnorm = fnorm;
582:     SNESLineSearchApply(snes->linesearch, X, F, &gnorm, Y);
583:     SNESLineSearchGetReason(snes->linesearch, &lssucceed);
584:     SNESLineSearchGetNorms(snes->linesearch, &xnorm, &gnorm, &ynorm);
585:     PetscInfo4(snes,"fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n",(double)fnorm,(double)gnorm,(double)ynorm,(int)lssucceed);
586:     if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break;
587:     if (snes->domainerror) {
588:       snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
589:       DMDestroyVI(snes->dm);
590:       return(0);
591:     }
592:     if (lssucceed) {
593:       if (++snes->numFailures >= snes->maxFailures) {
594:         PetscBool ismin;
595:         snes->reason = SNES_DIVERGED_LINE_SEARCH;
596:         SNESVICheckLocalMin_Private(snes,snes->jacobian,F,X,gnorm,&ismin);
597:         if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN;
598:         break;
599:       }
600:    }
601:    DMDestroyVI(snes->dm);
602:     /* Update function and solution vectors */
603:     fnorm = gnorm;
604:     /* Monitor convergence */
605:     PetscObjectSAWsTakeAccess((PetscObject)snes);
606:     snes->iter = i+1;
607:     snes->norm = fnorm;
608:     PetscObjectSAWsGrantAccess((PetscObject)snes);
609:     SNESLogConvergenceHistory(snes,snes->norm,lits);
610:     SNESMonitor(snes,snes->iter,snes->norm);
611:     /* Test for convergence, xnorm = || X || */
612:     if (snes->ops->converged != SNESConvergedSkip) { VecNorm(X,NORM_2,&xnorm); }
613:     (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&snes->reason,snes->cnvP);
614:     if (snes->reason) break;
615:   }
616:   /* make sure that the VI information attached to the DM is removed if the for loop above was broken early due to some exceptional conditional */
617:   DMDestroyVI(snes->dm);
618:   if (i == maxits) {
619:     PetscInfo1(snes,"Maximum number of iterations has been reached: %D\n",maxits);
620:     if (!snes->reason) snes->reason = SNES_DIVERGED_MAX_IT;
621:   }
622:   return(0);
623: }

625: PetscErrorCode SNESVISetRedundancyCheck(SNES snes,PetscErrorCode (*func)(SNES,IS,IS*,void*),void *ctx)
626: {
627:   SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS*)snes->data;

631:   vi->checkredundancy = func;
632:   vi->ctxP            = ctx;
633:   return(0);
634: }

636: #if defined(PETSC_HAVE_MATLAB_ENGINE)
637: #include <engine.h>
638: #include <mex.h>
639: typedef struct {char *funcname; mxArray *ctx;} SNESMatlabContext;

641: PetscErrorCode SNESVIRedundancyCheck_Matlab(SNES snes,IS is_act,IS *is_redact,void *ctx)
642: {
643:   PetscErrorCode    ierr;
644:   SNESMatlabContext *sctx = (SNESMatlabContext*)ctx;
645:   int               nlhs  = 1, nrhs = 5;
646:   mxArray           *plhs[1], *prhs[5];
647:   long long int     l1      = 0, l2 = 0, ls = 0;
648:   PetscInt          *indices=NULL;


656:   /* Create IS for reduced active set of size 0, its size and indices will
657:    bet set by the Matlab function */
658:   ISCreateGeneral(PetscObjectComm((PetscObject)snes),0,indices,PETSC_OWN_POINTER,is_redact);
659:   /* call Matlab function in ctx */
660:   PetscMemcpy(&ls,&snes,sizeof(snes));
661:   PetscMemcpy(&l1,&is_act,sizeof(is_act));
662:   PetscMemcpy(&l2,is_redact,sizeof(is_act));
663:   prhs[0] = mxCreateDoubleScalar((double)ls);
664:   prhs[1] = mxCreateDoubleScalar((double)l1);
665:   prhs[2] = mxCreateDoubleScalar((double)l2);
666:   prhs[3] = mxCreateString(sctx->funcname);
667:   prhs[4] = sctx->ctx;
668:   mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscSNESVIRedundancyCheckInternal");
669:   mxGetScalar(plhs[0]);
670:   mxDestroyArray(prhs[0]);
671:   mxDestroyArray(prhs[1]);
672:   mxDestroyArray(prhs[2]);
673:   mxDestroyArray(prhs[3]);
674:   mxDestroyArray(plhs[0]);
675:   return(0);
676: }

678: PetscErrorCode SNESVISetRedundancyCheckMatlab(SNES snes,const char *func,mxArray *ctx)
679: {
680:   PetscErrorCode    ierr;
681:   SNESMatlabContext *sctx;

684:   /* currently sctx is memory bleed */
685:   PetscNew(&sctx);
686:   PetscStrallocpy(func,&sctx->funcname);
687:   sctx->ctx = mxDuplicateArray(ctx);
688:   SNESVISetRedundancyCheck(snes,SNESVIRedundancyCheck_Matlab,sctx);
689:   return(0);
690: }

692: #endif

694: /* -------------------------------------------------------------------------- */
695: /*
696:    SNESSetUp_VINEWTONRSLS - Sets up the internal data structures for the later use
697:    of the SNESVI nonlinear solver.

699:    Input Parameter:
700: .  snes - the SNES context

702:    Application Interface Routine: SNESSetUp()

704:    Notes:
705:    For basic use of the SNES solvers, the user need not explicitly call
706:    SNESSetUp(), since these actions will automatically occur during
707:    the call to SNESSolve().
708:  */
709: PetscErrorCode SNESSetUp_VINEWTONRSLS(SNES snes)
710: {
711:   PetscErrorCode    ierr;
712:   SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS*) snes->data;
713:   PetscInt          *indices;
714:   PetscInt          i,n,rstart,rend;
715:   SNESLineSearch    linesearch;

718:   SNESSetUp_VI(snes);

720:   /* Set up previous active index set for the first snes solve
721:    vi->IS_inact_prev = 0,1,2,....N */

723:   VecGetOwnershipRange(snes->vec_sol,&rstart,&rend);
724:   VecGetLocalSize(snes->vec_sol,&n);
725:   PetscMalloc1(n,&indices);
726:   for (i=0; i < n; i++) indices[i] = rstart + i;
727:   ISCreateGeneral(PetscObjectComm((PetscObject)snes),n,indices,PETSC_OWN_POINTER,&vi->IS_inact_prev);

729:   /* set the line search functions */
730:   if (!snes->linesearch) {
731:     SNESGetLineSearch(snes, &linesearch);
732:     SNESLineSearchSetType(linesearch, SNESLINESEARCHBT);
733:   }
734:   return(0);
735: }
736: /* -------------------------------------------------------------------------- */
737: PetscErrorCode SNESReset_VINEWTONRSLS(SNES snes)
738: {
739:   SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS*) snes->data;
740:   PetscErrorCode    ierr;

743:   SNESReset_VI(snes);
744:   ISDestroy(&vi->IS_inact_prev);
745:   return(0);
746: }

748: /* -------------------------------------------------------------------------- */
749: /*MC
750:       SNESVINEWTONRSLS - Reduced space active set solvers for variational inequalities based on Newton's method

752:    Options Database:
753: +   -snes_type <vinewtonssls,vinewtonrsls> - a semi-smooth solver, a reduced space active set method
754: -   -snes_vi_monitor - prints the number of active constraints at each iteration.

756:    Level: beginner

758:    References:
759: .  1. - T. S. Munson, and S. Benson. Flexible Complementarity Solvers for Large Scale
760:      Applications, Optimization Methods and Software, 21 (2006).

762: .seealso:  SNESVISetVariableBounds(), SNESVISetComputeVariableBounds(), SNESCreate(), SNES, SNESSetType(), SNESVINEWTONSSLS, SNESNEWTONTR, SNESLineSearchSetType(),SNESLineSearchSetPostCheck(), SNESLineSearchSetPreCheck()

764: M*/
765: PETSC_EXTERN PetscErrorCode SNESCreate_VINEWTONRSLS(SNES snes)
766: {
767:   PetscErrorCode    ierr;
768:   SNES_VINEWTONRSLS *vi;

771:   snes->ops->reset          = SNESReset_VINEWTONRSLS;
772:   snes->ops->setup          = SNESSetUp_VINEWTONRSLS;
773:   snes->ops->solve          = SNESSolve_VINEWTONRSLS;
774:   snes->ops->destroy        = SNESDestroy_VI;
775:   snes->ops->setfromoptions = SNESSetFromOptions_VI;
776:   snes->ops->view           = NULL;
777:   snes->ops->converged      = SNESConvergedDefault_VI;

779:   snes->usesksp = PETSC_TRUE;
780:   snes->usesnpc = PETSC_FALSE;

782:   snes->alwayscomputesfinalresidual = PETSC_TRUE;

784:   PetscNewLog(snes,&vi);
785:   snes->data          = (void*)vi;
786:   vi->checkredundancy = NULL;

788:   PetscObjectComposeFunction((PetscObject)snes,"SNESVISetVariableBounds_C",SNESVISetVariableBounds_VI);
789:   PetscObjectComposeFunction((PetscObject)snes,"SNESVISetComputeVariableBounds_C",SNESVISetComputeVariableBounds_VI);
790:   return(0);
791: }