Actual source code: pack.c

petsc-3.4.5 2014-06-29
  2: #include <../src/dm/impls/composite/packimpl.h>       /*I  "petscdmcomposite.h"  I*/

  6: /*@C
  7:     DMCompositeSetCoupling - Sets user provided routines that compute the coupling between the
  8:       seperate components (DMs) in a DMto build the correct matrix nonzero structure.


 11:     Logically Collective on MPI_Comm

 13:     Input Parameter:
 14: +   dm - the composite object
 15: -   formcouplelocations - routine to set the nonzero locations in the matrix

 17:     Level: advanced

 19:     Notes: See DMSetApplicationContext() and DMGetApplicationContext() for how to get user information into
 20:         this routine

 22: @*/
 23: PetscErrorCode  DMCompositeSetCoupling(DM dm,PetscErrorCode (*FormCoupleLocations)(DM,Mat,PetscInt*,PetscInt*,PetscInt,PetscInt,PetscInt,PetscInt))
 24: {
 25:   DM_Composite *com = (DM_Composite*)dm->data;

 28:   com->FormCoupleLocations = FormCoupleLocations;
 29:   return(0);
 30: }

 34: PetscErrorCode  DMDestroy_Composite(DM dm)
 35: {
 36:   PetscErrorCode         ierr;
 37:   struct DMCompositeLink *next, *prev;
 38:   DM_Composite           *com = (DM_Composite*)dm->data;

 41:   next = com->next;
 42:   while (next) {
 43:     prev = next;
 44:     next = next->next;
 45:     DMDestroy(&prev->dm);
 46:     PetscFree(prev->grstarts);
 47:     PetscFree(prev);
 48:   }
 49:   /* This was originally freed in DMDestroy(), but that prevents reference counting of backend objects */
 50:   PetscFree(com);
 51:   return(0);
 52: }

 56: PetscErrorCode  DMView_Composite(DM dm,PetscViewer v)
 57: {
 59:   PetscBool      iascii;
 60:   DM_Composite   *com = (DM_Composite*)dm->data;

 63:   PetscObjectTypeCompare((PetscObject)v,PETSCVIEWERASCII,&iascii);
 64:   if (iascii) {
 65:     struct DMCompositeLink *lnk = com->next;
 66:     PetscInt               i;

 68:     PetscViewerASCIIPrintf(v,"DM (%s)\n",((PetscObject)dm)->prefix ? ((PetscObject)dm)->prefix : "no prefix");
 69:     PetscViewerASCIIPrintf(v,"  contains %D DMs\n",com->nDM);
 70:     PetscViewerASCIIPushTab(v);
 71:     for (i=0; lnk; lnk=lnk->next,i++) {
 72:       PetscViewerASCIIPrintf(v,"Link %D: DM of type %s\n",i,((PetscObject)lnk->dm)->type_name);
 73:       PetscViewerASCIIPushTab(v);
 74:       DMView(lnk->dm,v);
 75:       PetscViewerASCIIPopTab(v);
 76:     }
 77:     PetscViewerASCIIPopTab(v);
 78:   }
 79:   return(0);
 80: }

 82: /* --------------------------------------------------------------------------------------*/
 85: PetscErrorCode  DMSetUp_Composite(DM dm)
 86: {
 87:   PetscErrorCode         ierr;
 88:   PetscInt               nprev = 0;
 89:   PetscMPIInt            rank,size;
 90:   DM_Composite           *com  = (DM_Composite*)dm->data;
 91:   struct DMCompositeLink *next = com->next;
 92:   PetscLayout            map;

 95:   if (com->setup) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_ARG_WRONGSTATE,"Packer has already been setup");
 96:   PetscLayoutCreate(PetscObjectComm((PetscObject)dm),&map);
 97:   PetscLayoutSetLocalSize(map,com->n);
 98:   PetscLayoutSetSize(map,PETSC_DETERMINE);
 99:   PetscLayoutSetBlockSize(map,1);
100:   PetscLayoutSetUp(map);
101:   PetscLayoutGetSize(map,&com->N);
102:   PetscLayoutGetRange(map,&com->rstart,NULL);
103:   PetscLayoutDestroy(&map);

105:   /* now set the rstart for each linked vector */
106:   MPI_Comm_rank(PetscObjectComm((PetscObject)dm),&rank);
107:   MPI_Comm_size(PetscObjectComm((PetscObject)dm),&size);
108:   while (next) {
109:     next->rstart  = nprev;
110:     nprev        += next->n;
111:     next->grstart = com->rstart + next->rstart;
112:     PetscMalloc(size*sizeof(PetscInt),&next->grstarts);
113:     MPI_Allgather(&next->grstart,1,MPIU_INT,next->grstarts,1,MPIU_INT,PetscObjectComm((PetscObject)dm));
114:     next          = next->next;
115:   }
116:   com->setup = PETSC_TRUE;
117:   return(0);
118: }

120: /* ----------------------------------------------------------------------------------*/

124: /*@
125:     DMCompositeGetNumberDM - Get's the number of DM objects in the DMComposite
126:        representation.

128:     Not Collective

130:     Input Parameter:
131: .    dm - the packer object

133:     Output Parameter:
134: .     nDM - the number of DMs

136:     Level: beginner

138: @*/
139: PetscErrorCode  DMCompositeGetNumberDM(DM dm,PetscInt *nDM)
140: {
141:   DM_Composite *com = (DM_Composite*)dm->data;

145:   *nDM = com->nDM;
146:   return(0);
147: }


152: /*@C
153:     DMCompositeGetAccess - Allows one to access the individual packed vectors in their global
154:        representation.

156:     Collective on DMComposite

158:     Input Parameters:
159: +    dm - the packer object
160: -    gvec - the global vector

162:     Output Parameters:
163: .    Vec* ... - the packed parallel vectors, NULL for those that are not needed

165:     Notes: Use DMCompositeRestoreAccess() to return the vectors when you no longer need them

167:     Fortran Notes:

169:     Fortran callers must use numbered versions of this routine, e.g., DMCompositeGetAccess4(dm,gvec,vec1,vec2,vec3,vec4)
170:     or use the alternative interface DMCompositeGetAccessArray().

172:     Level: advanced

174: .seealso: DMCompositeGetEntries(), DMCompositeScatter()
175: @*/
176: PetscErrorCode  DMCompositeGetAccess(DM dm,Vec gvec,...)
177: {
178:   va_list                Argp;
179:   PetscErrorCode         ierr;
180:   struct DMCompositeLink *next;
181:   DM_Composite           *com = (DM_Composite*)dm->data;

186:   next = com->next;
187:   if (!com->setup) {
188:     DMSetUp(dm);
189:   }

191:   /* loop over packed objects, handling one at at time */
192:   va_start(Argp,gvec);
193:   while (next) {
194:     Vec *vec;
195:     vec = va_arg(Argp, Vec*);
196:     if (vec) {
197:       PetscScalar *array;
198:       DMGetGlobalVector(next->dm,vec);
199:       VecGetArray(gvec,&array);
200:       VecPlaceArray(*vec,array+next->rstart);
201:       VecRestoreArray(gvec,&array);
202:     }
203:     next = next->next;
204:   }
205:   va_end(Argp);
206:   return(0);
207: }

211: /*@C
212:     DMCompositeGetAccessArray - Allows one to access the individual packed vectors in their global
213:        representation.

215:     Collective on DMComposite

217:     Input Parameters:
218: +    dm - the packer object
219: .    pvec - packed vector
220: .    nwanted - number of vectors wanted
221: -    wanted - sorted array of vectors wanted, or NULL to get all vectors

223:     Output Parameters:
224: .    vecs - array of requested global vectors (must be allocated)

226:     Notes: Use DMCompositeRestoreAccessArray() to return the vectors when you no longer need them

228:     Level: advanced

230: .seealso: DMCompositeGetAccess(), DMCompositeGetEntries(), DMCompositeScatter(), DMCompositeGather()
231: @*/
232: PetscErrorCode  DMCompositeGetAccessArray(DM dm,Vec pvec,PetscInt nwanted,const PetscInt *wanted,Vec *vecs)
233: {
234:   PetscErrorCode         ierr;
235:   struct DMCompositeLink *link;
236:   PetscInt               i,wnum;
237:   DM_Composite           *com = (DM_Composite*)dm->data;

242:   if (!com->setup) {
243:     DMSetUp(dm);
244:   }

246:   for (i=0,wnum=0,link=com->next; link && wnum<nwanted; i++,link=link->next) {
247:     if (!wanted || i == wanted[wnum]) {
248:       PetscScalar *array;
249:       Vec v;
250:       DMGetGlobalVector(link->dm,&v);
251:       VecGetArray(pvec,&array);
252:       VecPlaceArray(v,array+link->rstart);
253:       VecRestoreArray(pvec,&array);
254:       vecs[wnum++] = v;
255:     }
256:   }
257:   return(0);
258: }

262: /*@C
263:     DMCompositeRestoreAccess - Returns the vectors obtained with DMCompositeGetAccess()
264:        representation.

266:     Collective on DMComposite

268:     Input Parameters:
269: +    dm - the packer object
270: .    gvec - the global vector
271: -    Vec* ... - the individual parallel vectors, NULL for those that are not needed

273:     Level: advanced

275: .seealso  DMCompositeAddDM(), DMCreateGlobalVector(),
276:          DMCompositeGather(), DMCompositeCreate(), DMCompositeGetISLocalToGlobalMappings(), DMCompositeScatter(),
277:          DMCompositeRestoreAccess(), DMCompositeGetAccess()

279: @*/
280: PetscErrorCode  DMCompositeRestoreAccess(DM dm,Vec gvec,...)
281: {
282:   va_list                Argp;
283:   PetscErrorCode         ierr;
284:   struct DMCompositeLink *next;
285:   DM_Composite           *com = (DM_Composite*)dm->data;

290:   next = com->next;
291:   if (!com->setup) {
292:     DMSetUp(dm);
293:   }

295:   /* loop over packed objects, handling one at at time */
296:   va_start(Argp,gvec);
297:   while (next) {
298:     Vec *vec;
299:     vec = va_arg(Argp, Vec*);
300:     if (vec) {
301:       VecResetArray(*vec);
302:       DMRestoreGlobalVector(next->dm,vec);
303:     }
304:     next = next->next;
305:   }
306:   va_end(Argp);
307:   return(0);
308: }

312: /*@C
313:     DMCompositeRestoreAccessArray - Returns the vectors obtained with DMCompositeGetAccessArray()

315:     Collective on DMComposite

317:     Input Parameters:
318: +    dm - the packer object
319: .    pvec - packed vector
320: .    nwanted - number of vectors wanted
321: .    wanted - sorted array of vectors wanted, or NULL to get all vectors
322: -    vecs - array of global vectors to return

324:     Level: advanced

326: .seealso: DMCompositeRestoreAccess(), DMCompositeRestoreEntries(), DMCompositeScatter(), DMCompositeGather()
327: @*/
328: PetscErrorCode  DMCompositeRestoreAccessArray(DM dm,Vec pvec,PetscInt nwanted,const PetscInt *wanted,Vec *vecs)
329: {
330:   PetscErrorCode         ierr;
331:   struct DMCompositeLink *link;
332:   PetscInt               i,wnum;
333:   DM_Composite           *com = (DM_Composite*)dm->data;

338:   if (!com->setup) {
339:     DMSetUp(dm);
340:   }

342:   for (i=0,wnum=0,link=com->next; link && wnum<nwanted; i++,link=link->next) {
343:     if (!wanted || i == wanted[wnum]) {
344:       VecResetArray(vecs[wnum]);
345:       DMRestoreGlobalVector(link->dm,&vecs[wnum]);
346:       wnum++;
347:     }
348:   }
349:   return(0);
350: }

354: /*@C
355:     DMCompositeScatter - Scatters from a global packed vector into its individual local vectors

357:     Collective on DMComposite

359:     Input Parameters:
360: +    dm - the packer object
361: .    gvec - the global vector
362: -    Vec ... - the individual sequential vectors, NULL for those that are not needed

364:     Level: advanced

366:     Notes:
367:     DMCompositeScatterArray() is a non-variadic alternative that is often more convenient for library callers and is
368:     accessible from Fortran.

370: .seealso DMDestroy(), DMCompositeAddDM(), DMCreateGlobalVector(),
371:          DMCompositeGather(), DMCompositeCreate(), DMCompositeGetISLocalToGlobalMappings(), DMCompositeGetAccess(),
372:          DMCompositeGetLocalVectors(), DMCompositeRestoreLocalVectors(), DMCompositeGetEntries()
373:          DMCompositeScatterArray()

375: @*/
376: PetscErrorCode  DMCompositeScatter(DM dm,Vec gvec,...)
377: {
378:   va_list                Argp;
379:   PetscErrorCode         ierr;
380:   struct DMCompositeLink *next;
381:   PetscInt               cnt;
382:   DM_Composite           *com = (DM_Composite*)dm->data;

387:   if (!com->setup) {
388:     DMSetUp(dm);
389:   }

391:   /* loop over packed objects, handling one at at time */
392:   va_start(Argp,gvec);
393:   for (cnt=3,next=com->next; next; cnt++,next=next->next) {
394:     Vec local;
395:     local = va_arg(Argp, Vec);
396:     if (local) {
397:       Vec         global;
398:       PetscScalar *array;
400:       DMGetGlobalVector(next->dm,&global);
401:       VecGetArray(gvec,&array);
402:       VecPlaceArray(global,array+next->rstart);
403:       DMGlobalToLocalBegin(next->dm,global,INSERT_VALUES,local);
404:       DMGlobalToLocalEnd(next->dm,global,INSERT_VALUES,local);
405:       VecRestoreArray(gvec,&array);
406:       VecResetArray(global);
407:       DMRestoreGlobalVector(next->dm,&global);
408:     }
409:   }
410:   va_end(Argp);
411:   return(0);
412: }

416: /*@
417:     DMCompositeScatterArray - Scatters from a global packed vector into its individual local vectors

419:     Collective on DMComposite

421:     Input Parameters:
422: +    dm - the packer object
423: .    gvec - the global vector
424: .    lvecs - array of local vectors, NULL for any that are not needed

426:     Level: advanced

428:     Note:
429:     This is a non-variadic alternative to DMCompositeScatterArray()

431: .seealso DMDestroy(), DMCompositeAddDM(), DMCreateGlobalVector()
432:          DMCompositeGather(), DMCompositeCreate(), DMCompositeGetISLocalToGlobalMappings(), DMCompositeGetAccess(),
433:          DMCompositeGetLocalVectors(), DMCompositeRestoreLocalVectors(), DMCompositeGetEntries()

435: @*/
436: PetscErrorCode  DMCompositeScatterArray(DM dm,Vec gvec,Vec *lvecs)
437: {
438:   PetscErrorCode         ierr;
439:   struct DMCompositeLink *next;
440:   PetscInt               i;
441:   DM_Composite           *com = (DM_Composite*)dm->data;

446:   if (!com->setup) {
447:     DMSetUp(dm);
448:   }

450:   /* loop over packed objects, handling one at at time */
451:   for (i=0,next=com->next; next; next=next->next,i++) {
452:     if (lvecs[i]) {
453:       Vec         global;
454:       PetscScalar *array;
456:       DMGetGlobalVector(next->dm,&global);
457:       VecGetArray(gvec,&array);
458:       VecPlaceArray(global,array+next->rstart);
459:       DMGlobalToLocalBegin(next->dm,global,INSERT_VALUES,lvecs[i]);
460:       DMGlobalToLocalEnd(next->dm,global,INSERT_VALUES,lvecs[i]);
461:       VecRestoreArray(gvec,&array);
462:       VecResetArray(global);
463:       DMRestoreGlobalVector(next->dm,&global);
464:     }
465:   }
466:   return(0);
467: }

471: /*@C
472:     DMCompositeGather - Gathers into a global packed vector from its individual local vectors

474:     Collective on DMComposite

476:     Input Parameter:
477: +    dm - the packer object
478: .    gvec - the global vector
479: -    Vec ... - the individual sequential vectors, NULL for any that are not needed

481:     Level: advanced

483: .seealso DMDestroy(), DMCompositeAddDM(), DMCreateGlobalVector(),
484:          DMCompositeScatter(), DMCompositeCreate(), DMCompositeGetISLocalToGlobalMappings(), DMCompositeGetAccess(),
485:          DMCompositeGetLocalVectors(), DMCompositeRestoreLocalVectors(), DMCompositeGetEntries()

487: @*/
488: PetscErrorCode  DMCompositeGather(DM dm,Vec gvec,InsertMode imode,...)
489: {
490:   va_list                Argp;
491:   PetscErrorCode         ierr;
492:   struct DMCompositeLink *next;
493:   DM_Composite           *com = (DM_Composite*)dm->data;
494:   PetscInt               cnt;

499:   if (!com->setup) {
500:     DMSetUp(dm);
501:   }

503:   /* loop over packed objects, handling one at at time */
504:   va_start(Argp,imode);
505:   for (cnt=3,next=com->next; next; cnt++,next=next->next) {
506:     Vec local;
507:     local = va_arg(Argp, Vec);
508:     if (local) {
509:       PetscScalar *array;
510:       Vec         global;
512:       DMGetGlobalVector(next->dm,&global);
513:       VecGetArray(gvec,&array);
514:       VecPlaceArray(global,array+next->rstart);
515:       DMLocalToGlobalBegin(next->dm,local,imode,global);
516:       DMLocalToGlobalEnd(next->dm,local,imode,global);
517:       VecRestoreArray(gvec,&array);
518:       VecResetArray(global);
519:       DMRestoreGlobalVector(next->dm,&global);
520:     }
521:   }
522:   va_end(Argp);
523:   return(0);
524: }

528: /*@
529:     DMCompositeGatherArray - Gathers into a global packed vector from its individual local vectors

531:     Collective on DMComposite

533:     Input Parameter:
534: +    dm - the packer object
535: .    gvec - the global vector
536: -    lvecs - the individual sequential vectors, NULL for any that are not needed

538:     Level: advanced

540:     Notes:
541:     This is a non-variadic alternative to DMCompositeGather().

543: .seealso DMDestroy(), DMCompositeAddDM(), DMCreateGlobalVector(),
544:          DMCompositeScatter(), DMCompositeCreate(), DMCompositeGetISLocalToGlobalMappings(), DMCompositeGetAccess(),
545:          DMCompositeGetLocalVectors(), DMCompositeRestoreLocalVectors(), DMCompositeGetEntries(),
546: @*/
547: PetscErrorCode  DMCompositeGatherArray(DM dm,Vec gvec,InsertMode imode,Vec *lvecs)
548: {
549:   PetscErrorCode         ierr;
550:   struct DMCompositeLink *next;
551:   DM_Composite           *com = (DM_Composite*)dm->data;
552:   PetscInt               i;

557:   if (!com->setup) {
558:     DMSetUp(dm);
559:   }

561:   /* loop over packed objects, handling one at at time */
562:   for (next=com->next,i=0; next; next=next->next,i++) {
563:     if (lvecs[i]) {
564:       PetscScalar *array;
565:       Vec         global;
567:       DMGetGlobalVector(next->dm,&global);
568:       VecGetArray(gvec,&array);
569:       VecPlaceArray(global,array+next->rstart);
570:       DMLocalToGlobalBegin(next->dm,lvecs[i],imode,global);
571:       DMLocalToGlobalEnd(next->dm,lvecs[i],imode,global);
572:       VecRestoreArray(gvec,&array);
573:       VecResetArray(global);
574:       DMRestoreGlobalVector(next->dm,&global);
575:     }
576:   }
577:   return(0);
578: }

582: /*@C
583:     DMCompositeAddDM - adds a DM  vector to a DMComposite

585:     Collective on DMComposite

587:     Input Parameter:
588: +    dm - the packer object
589: -    dm - the DM object, if the DM is a da you will need to caste it with a (DM)

591:     Level: advanced

593: .seealso DMDestroy(), DMCompositeGather(), DMCompositeAddDM(), DMCreateGlobalVector(),
594:          DMCompositeScatter(), DMCompositeCreate(), DMCompositeGetISLocalToGlobalMappings(), DMCompositeGetAccess(),
595:          DMCompositeGetLocalVectors(), DMCompositeRestoreLocalVectors(), DMCompositeGetEntries()

597: @*/
598: PetscErrorCode  DMCompositeAddDM(DM dmc,DM dm)
599: {
600:   PetscErrorCode         ierr;
601:   PetscInt               n,nlocal;
602:   struct DMCompositeLink *mine,*next;
603:   Vec                    global,local;
604:   DM_Composite           *com = (DM_Composite*)dmc->data;

609:   next = com->next;
610:   if (com->setup) SETERRQ(PetscObjectComm((PetscObject)dmc),PETSC_ERR_ARG_WRONGSTATE,"Cannot add a DM once you have used the DMComposite");

612:   /* create new link */
613:   PetscNew(struct DMCompositeLink,&mine);
614:   PetscObjectReference((PetscObject)dm);
615:   DMGetGlobalVector(dm,&global);
616:   VecGetLocalSize(global,&n);
617:   DMRestoreGlobalVector(dm,&global);
618:   DMGetLocalVector(dm,&local);
619:   VecGetSize(local,&nlocal);
620:   DMRestoreLocalVector(dm,&local);

622:   mine->n      = n;
623:   mine->nlocal = nlocal;
624:   mine->dm     = dm;
625:   mine->next   = NULL;
626:   com->n      += n;

628:   /* add to end of list */
629:   if (!next) com->next = mine;
630:   else {
631:     while (next->next) next = next->next;
632:     next->next = mine;
633:   }
634:   com->nDM++;
635:   com->nmine++;
636:   return(0);
637: }

639: #include <petscdraw.h>
640: PETSC_EXTERN PetscErrorCode  VecView_MPI(Vec,PetscViewer);
643: PetscErrorCode  VecView_DMComposite(Vec gvec,PetscViewer viewer)
644: {
645:   DM                     dm;
646:   PetscErrorCode         ierr;
647:   struct DMCompositeLink *next;
648:   PetscBool              isdraw;
649:   DM_Composite           *com;

652:   VecGetDM(gvec, &dm);
653:   if (!dm) SETERRQ(PetscObjectComm((PetscObject)gvec),PETSC_ERR_ARG_WRONG,"Vector not generated from a DMComposite");
654:   com  = (DM_Composite*)dm->data;
655:   next = com->next;

657:   PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);
658:   if (!isdraw) {
659:     /* do I really want to call this? */
660:     VecView_MPI(gvec,viewer);
661:   } else {
662:     PetscInt cnt = 0;

664:     /* loop over packed objects, handling one at at time */
665:     while (next) {
666:       Vec         vec;
667:       PetscScalar *array;
668:       PetscInt    bs;

670:       /* Should use VecGetSubVector() eventually, but would need to forward the DM for that to work */
671:       DMGetGlobalVector(next->dm,&vec);
672:       VecGetArray(gvec,&array);
673:       VecPlaceArray(vec,array+next->rstart);
674:       VecRestoreArray(gvec,&array);
675:       VecView(vec,viewer);
676:       VecGetBlockSize(vec,&bs);
677:       VecResetArray(vec);
678:       DMRestoreGlobalVector(next->dm,&vec);
679:       PetscViewerDrawBaseAdd(viewer,bs);
680:       cnt += bs;
681:       next = next->next;
682:     }
683:     PetscViewerDrawBaseAdd(viewer,-cnt);
684:   }
685:   return(0);
686: }

690: PetscErrorCode  DMCreateGlobalVector_Composite(DM dm,Vec *gvec)
691: {
693:   DM_Composite   *com = (DM_Composite*)dm->data;

697:   DMSetUp(dm);
698:   VecCreateMPI(PetscObjectComm((PetscObject)dm),com->n,com->N,gvec);
699:   VecSetDM(*gvec, dm);
700:   VecSetOperation(*gvec,VECOP_VIEW,(void (*)(void))VecView_DMComposite);
701:   return(0);
702: }

706: PetscErrorCode  DMCreateLocalVector_Composite(DM dm,Vec *lvec)
707: {
709:   DM_Composite   *com = (DM_Composite*)dm->data;

713:   if (!com->setup) {
714:     DMSetUp(dm);
715:   }
716:   VecCreateSeq(PetscObjectComm((PetscObject)dm),com->nghost,lvec);
717:   VecSetDM(*lvec, dm);
718:   return(0);
719: }

723: /*@C
724:     DMCompositeGetISLocalToGlobalMappings - gets an ISLocalToGlobalMapping for each DM in the DMComposite, maps to the composite global space

726:     Collective on DM

728:     Input Parameter:
729: .    dm - the packer object

731:     Output Parameters:
732: .    ltogs - the individual mappings for each packed vector. Note that this includes
733:            all the ghost points that individual ghosted DMDA's may have.

735:     Level: advanced

737:     Notes:
738:        Each entry of ltogs should be destroyed with ISLocalToGlobalMappingDestroy(), the ltogs array should be freed with PetscFree().

740: .seealso DMDestroy(), DMCompositeAddDM(), DMCreateGlobalVector(),
741:          DMCompositeGather(), DMCompositeCreate(), DMCompositeGetAccess(), DMCompositeScatter(),
742:          DMCompositeGetLocalVectors(), DMCompositeRestoreLocalVectors(),DMCompositeGetEntries()

744: @*/
745: PetscErrorCode  DMCompositeGetISLocalToGlobalMappings(DM dm,ISLocalToGlobalMapping **ltogs)
746: {
747:   PetscErrorCode         ierr;
748:   PetscInt               i,*idx,n,cnt;
749:   struct DMCompositeLink *next;
750:   PetscMPIInt            rank;
751:   DM_Composite           *com = (DM_Composite*)dm->data;

755:   DMSetUp(dm);
756:   PetscMalloc((com->nDM)*sizeof(ISLocalToGlobalMapping),ltogs);
757:   next = com->next;
758:   MPI_Comm_rank(PetscObjectComm((PetscObject)dm),&rank);

760:   /* loop over packed objects, handling one at at time */
761:   cnt = 0;
762:   while (next) {
763:     ISLocalToGlobalMapping ltog;
764:     PetscMPIInt            size;
765:     const PetscInt         *suboff,*indices;
766:     Vec                    global;

768:     /* Get sub-DM global indices for each local dof */
769:     DMGetLocalToGlobalMapping(next->dm,&ltog);
770:     ISLocalToGlobalMappingGetSize(ltog,&n);
771:     ISLocalToGlobalMappingGetIndices(ltog,&indices);
772:     PetscMalloc(n*sizeof(PetscInt),&idx);

774:     /* Get the offsets for the sub-DM global vector */
775:     DMGetGlobalVector(next->dm,&global);
776:     VecGetOwnershipRanges(global,&suboff);
777:     MPI_Comm_size(PetscObjectComm((PetscObject)global),&size);

779:     /* Shift the sub-DM definition of the global space to the composite global space */
780:     for (i=0; i<n; i++) {
781:       PetscInt subi = indices[i],lo = 0,hi = size,t;
782:       /* Binary search to find which rank owns subi */
783:       while (hi-lo > 1) {
784:         t = lo + (hi-lo)/2;
785:         if (suboff[t] > subi) hi = t;
786:         else                  lo = t;
787:       }
788:       idx[i] = subi - suboff[lo] + next->grstarts[lo];
789:     }
790:     ISLocalToGlobalMappingRestoreIndices(ltog,&indices);
791:     ISLocalToGlobalMappingCreate(PetscObjectComm((PetscObject)dm),n,idx,PETSC_OWN_POINTER,&(*ltogs)[cnt]);
792:     DMRestoreGlobalVector(next->dm,&global);
793:     next = next->next;
794:     cnt++;
795:   }
796:   return(0);
797: }

801: /*@C
802:    DMCompositeGetLocalISs - Gets index sets for each component of a composite local vector

804:    Not Collective

806:    Input Arguments:
807: . dm - composite DM

809:    Output Arguments:
810: . is - array of serial index sets for each each component of the DMComposite

812:    Level: intermediate

814:    Notes:
815:    At present, a composite local vector does not normally exist.  This function is used to provide index sets for
816:    MatGetLocalSubMatrix().  In the future, the scatters for each entry in the DMComposite may be be merged into a single
817:    scatter to a composite local vector.  The user should not typically need to know which is being done.

819:    To get the composite global indices at all local points (including ghosts), use DMCompositeGetISLocalToGlobalMappings().

821:    To get index sets for pieces of the composite global vector, use DMCompositeGetGlobalISs().

823:    Each returned IS should be destroyed with ISDestroy(), the array should be freed with PetscFree().

825: .seealso: DMCompositeGetGlobalISs(), DMCompositeGetISLocalToGlobalMappings(), MatGetLocalSubMatrix(), MatCreateLocalRef()
826: @*/
827: PetscErrorCode  DMCompositeGetLocalISs(DM dm,IS **is)
828: {
829:   PetscErrorCode         ierr;
830:   DM_Composite           *com = (DM_Composite*)dm->data;
831:   struct DMCompositeLink *link;
832:   PetscInt               cnt,start;

837:   PetscMalloc(com->nmine*sizeof(IS),is);
838:   for (cnt=0,start=0,link=com->next; link; start+=link->nlocal,cnt++,link=link->next) {
839:     PetscInt bs;
840:     ISCreateStride(PETSC_COMM_SELF,link->nlocal,start,1,&(*is)[cnt]);
841:     DMGetBlockSize(link->dm,&bs);
842:     ISSetBlockSize((*is)[cnt],bs);
843:   }
844:   return(0);
845: }

849: /*@C
850:     DMCompositeGetGlobalISs - Gets the index sets for each composed object

852:     Collective on DMComposite

854:     Input Parameter:
855: .    dm - the packer object

857:     Output Parameters:
858: .    is - the array of index sets

860:     Level: advanced

862:     Notes:
863:        The is entries should be destroyed with ISDestroy(), the is array should be freed with PetscFree()

865:        These could be used to extract a subset of vector entries for a "multi-physics" preconditioner

867:        Use DMCompositeGetLocalISs() for index sets in the packed local numbering, and
868:        DMCompositeGetISLocalToGlobalMappings() for to map local sub-DM (including ghost) indices to packed global
869:        indices.

871: .seealso DMDestroy(), DMCompositeAddDM(), DMCreateGlobalVector(),
872:          DMCompositeGather(), DMCompositeCreate(), DMCompositeGetAccess(), DMCompositeScatter(),
873:          DMCompositeGetLocalVectors(), DMCompositeRestoreLocalVectors(),DMCompositeGetEntries()

875: @*/

877: PetscErrorCode  DMCompositeGetGlobalISs(DM dm,IS *is[])
878: {
879:   PetscErrorCode         ierr;
880:   PetscInt               cnt = 0,*idx,i;
881:   struct DMCompositeLink *next;
882:   PetscMPIInt            rank;
883:   DM_Composite           *com = (DM_Composite*)dm->data;

887:   PetscMalloc((com->nDM)*sizeof(IS),is);
888:   next = com->next;
889:   MPI_Comm_rank(PetscObjectComm((PetscObject)dm),&rank);

891:   /* loop over packed objects, handling one at at time */
892:   while (next) {
893:     PetscMalloc(next->n*sizeof(PetscInt),&idx);
894:     for (i=0; i<next->n; i++) idx[i] = next->grstart + i;
895:     ISCreateGeneral(PetscObjectComm((PetscObject)dm),next->n,idx,PETSC_OWN_POINTER,&(*is)[cnt]);
896:     cnt++;
897:     next = next->next;
898:   }
899:   return(0);
900: }

904: PetscErrorCode DMCreateFieldIS_Composite(DM dm, PetscInt *numFields,char ***fieldNames, IS **fields)
905: {
906:   PetscInt       nDM;
907:   DM             *dms;
908:   PetscInt       i;

912:   DMCompositeGetNumberDM(dm, &nDM);
913:   if (numFields) *numFields = nDM;
914:   DMCompositeGetGlobalISs(dm, fields);
915:   if (fieldNames) {
916:     PetscMalloc(nDM*sizeof(DM), &dms);
917:     PetscMalloc(nDM*sizeof(const char*), fieldNames);
918:     DMCompositeGetEntriesArray(dm, dms);
919:     for (i=0; i<nDM; i++) {
920:       char       buf[256];
921:       const char *splitname;

923:       /* Split naming precedence: object name, prefix, number */
924:       splitname = ((PetscObject) dm)->name;
925:       if (!splitname) {
926:         PetscObjectGetOptionsPrefix((PetscObject)dms[i],&splitname);
927:         if (splitname) {
928:           size_t len;
929:           PetscStrncpy(buf,splitname,sizeof(buf));
930:           buf[sizeof(buf) - 1] = 0;
931:           PetscStrlen(buf,&len);
932:           if (buf[len-1] == '_') buf[len-1] = 0; /* Remove trailing underscore if it was used */
933:           splitname = buf;
934:         }
935:       }
936:       if (!splitname) {
937:         PetscSNPrintf(buf,sizeof(buf),"%D",i);
938:         splitname = buf;
939:       }
940:       PetscStrallocpy(splitname,&(*fieldNames)[i]);
941:     }
942:     PetscFree(dms);
943:   }
944:   return(0);
945: }

947: /*
948:  This could take over from DMCreateFieldIS(), as it is more general,
949:  making DMCreateFieldIS() a special case -- calling with dmlist == NULL;
950:  At this point it's probably best to be less intrusive, however.
951:  */
954: PetscErrorCode DMCreateFieldDecomposition_Composite(DM dm, PetscInt *len,char ***namelist, IS **islist, DM **dmlist)
955: {
956:   PetscInt       nDM;
957:   PetscInt       i;

961:   DMCreateFieldIS_Composite(dm, len, namelist, islist);
962:   if (dmlist) {
963:     DMCompositeGetNumberDM(dm, &nDM);
964:     PetscMalloc(nDM*sizeof(DM), dmlist);
965:     DMCompositeGetEntriesArray(dm, *dmlist);
966:     for (i=0; i<nDM; i++) {
967:       PetscObjectReference((PetscObject)((*dmlist)[i]));
968:     }
969:   }
970:   return(0);
971: }



975: /* -------------------------------------------------------------------------------------*/
978: /*@C
979:     DMCompositeGetLocalVectors - Gets local vectors for each part of a DMComposite.
980:        Use DMCompositeRestoreLocalVectors() to return them.

982:     Not Collective

984:     Input Parameter:
985: .    dm - the packer object

987:     Output Parameter:
988: .   Vec ... - the individual sequential Vecs

990:     Level: advanced

992: .seealso DMDestroy(), DMCompositeAddDM(), DMCreateGlobalVector(),
993:          DMCompositeGather(), DMCompositeCreate(), DMCompositeGetISLocalToGlobalMappings(), DMCompositeGetAccess(),
994:          DMCompositeRestoreLocalVectors(), DMCompositeScatter(), DMCompositeGetEntries()

996: @*/
997: PetscErrorCode  DMCompositeGetLocalVectors(DM dm,...)
998: {
999:   va_list                Argp;
1000:   PetscErrorCode         ierr;
1001:   struct DMCompositeLink *next;
1002:   DM_Composite           *com = (DM_Composite*)dm->data;

1006:   next = com->next;
1007:   /* loop over packed objects, handling one at at time */
1008:   va_start(Argp,dm);
1009:   while (next) {
1010:     Vec *vec;
1011:     vec = va_arg(Argp, Vec*);
1012:     if (vec) {DMGetLocalVector(next->dm,vec);}
1013:     next = next->next;
1014:   }
1015:   va_end(Argp);
1016:   return(0);
1017: }

1021: /*@C
1022:     DMCompositeRestoreLocalVectors - Restores local vectors for each part of a DMComposite.

1024:     Not Collective

1026:     Input Parameter:
1027: .    dm - the packer object

1029:     Output Parameter:
1030: .   Vec ... - the individual sequential Vecs

1032:     Level: advanced

1034: .seealso DMDestroy(), DMCompositeAddDM(), DMCreateGlobalVector(),
1035:          DMCompositeGather(), DMCompositeCreate(), DMCompositeGetISLocalToGlobalMappings(), DMCompositeGetAccess(),
1036:          DMCompositeGetLocalVectors(), DMCompositeScatter(), DMCompositeGetEntries()

1038: @*/
1039: PetscErrorCode  DMCompositeRestoreLocalVectors(DM dm,...)
1040: {
1041:   va_list                Argp;
1042:   PetscErrorCode         ierr;
1043:   struct DMCompositeLink *next;
1044:   DM_Composite           *com = (DM_Composite*)dm->data;

1048:   next = com->next;
1049:   /* loop over packed objects, handling one at at time */
1050:   va_start(Argp,dm);
1051:   while (next) {
1052:     Vec *vec;
1053:     vec = va_arg(Argp, Vec*);
1054:     if (vec) {DMRestoreLocalVector(next->dm,vec);}
1055:     next = next->next;
1056:   }
1057:   va_end(Argp);
1058:   return(0);
1059: }

1061: /* -------------------------------------------------------------------------------------*/
1064: /*@C
1065:     DMCompositeGetEntries - Gets the DM for each entry in a DMComposite.

1067:     Not Collective

1069:     Input Parameter:
1070: .    dm - the packer object

1072:     Output Parameter:
1073: .   DM ... - the individual entries (DMs)

1075:     Level: advanced

1077: .seealso DMDestroy(), DMCompositeAddDM(), DMCreateGlobalVector(), DMCompositeGetEntriesArray()
1078:          DMCompositeGather(), DMCompositeCreate(), DMCompositeGetISLocalToGlobalMappings(), DMCompositeGetAccess(),
1079:          DMCompositeRestoreLocalVectors(), DMCompositeGetLocalVectors(),  DMCompositeScatter(),
1080:          DMCompositeGetLocalVectors(), DMCompositeRestoreLocalVectors()

1082: @*/
1083: PetscErrorCode  DMCompositeGetEntries(DM dm,...)
1084: {
1085:   va_list                Argp;
1086:   struct DMCompositeLink *next;
1087:   DM_Composite           *com = (DM_Composite*)dm->data;

1091:   next = com->next;
1092:   /* loop over packed objects, handling one at at time */
1093:   va_start(Argp,dm);
1094:   while (next) {
1095:     DM *dmn;
1096:     dmn = va_arg(Argp, DM*);
1097:     if (dmn) *dmn = next->dm;
1098:     next = next->next;
1099:   }
1100:   va_end(Argp);
1101:   return(0);
1102: }

1106: /*@C
1107:     DMCompositeGetEntriesArray - Gets the DM for each entry in a DMComposite.

1109:     Not Collective

1111:     Input Parameter:
1112: +    dm - the packer object
1113: -    dms - array of sufficient length (see DMCompositeGetNumberDM()), holds the DMs on output

1115:     Level: advanced

1117: .seealso DMDestroy(), DMCompositeAddDM(), DMCreateGlobalVector(), DMCompositeGetEntries()
1118:          DMCompositeGather(), DMCompositeCreate(), DMCompositeGetISLocalToGlobalMappings(), DMCompositeGetAccess(),
1119:          DMCompositeRestoreLocalVectors(), DMCompositeGetLocalVectors(),  DMCompositeScatter(),
1120:          DMCompositeGetLocalVectors(), DMCompositeRestoreLocalVectors()

1122: @*/
1123: PetscErrorCode DMCompositeGetEntriesArray(DM dm,DM dms[])
1124: {
1125:   struct DMCompositeLink *next;
1126:   DM_Composite           *com = (DM_Composite*)dm->data;
1127:   PetscInt               i;

1131:   /* loop over packed objects, handling one at at time */
1132:   for (next=com->next,i=0; next; next=next->next,i++) dms[i] = next->dm;
1133:   return(0);
1134: }

1138: PetscErrorCode  DMRefine_Composite(DM dmi,MPI_Comm comm,DM *fine)
1139: {
1140:   PetscErrorCode         ierr;
1141:   struct DMCompositeLink *next;
1142:   DM_Composite           *com = (DM_Composite*)dmi->data;
1143:   DM                     dm;

1147:   if (comm == MPI_COMM_NULL) {
1148:     PetscObjectGetComm((PetscObject)dmi,&comm);
1149:   }
1150:   DMSetUp(dmi);
1151:   next = com->next;
1152:   DMCompositeCreate(comm,fine);

1154:   /* loop over packed objects, handling one at at time */
1155:   while (next) {
1156:     DMRefine(next->dm,comm,&dm);
1157:     DMCompositeAddDM(*fine,dm);
1158:     PetscObjectDereference((PetscObject)dm);
1159:     next = next->next;
1160:   }
1161:   return(0);
1162: }

1166: PetscErrorCode  DMCoarsen_Composite(DM dmi,MPI_Comm comm,DM *fine)
1167: {
1168:   PetscErrorCode         ierr;
1169:   struct DMCompositeLink *next;
1170:   DM_Composite           *com = (DM_Composite*)dmi->data;
1171:   DM                     dm;

1175:   DMSetUp(dmi);
1176:   if (comm == MPI_COMM_NULL) {
1177:     PetscObjectGetComm((PetscObject)dmi,&comm);
1178:   }
1179:   next = com->next;
1180:   DMCompositeCreate(comm,fine);

1182:   /* loop over packed objects, handling one at at time */
1183:   while (next) {
1184:     DMCoarsen(next->dm,comm,&dm);
1185:     DMCompositeAddDM(*fine,dm);
1186:     PetscObjectDereference((PetscObject)dm);
1187:     next = next->next;
1188:   }
1189:   return(0);
1190: }

1194: PetscErrorCode  DMCreateInterpolation_Composite(DM coarse,DM fine,Mat *A,Vec *v)
1195: {
1196:   PetscErrorCode         ierr;
1197:   PetscInt               m,n,M,N,nDM,i;
1198:   struct DMCompositeLink *nextc;
1199:   struct DMCompositeLink *nextf;
1200:   Vec                    gcoarse,gfine,*vecs;
1201:   DM_Composite           *comcoarse = (DM_Composite*)coarse->data;
1202:   DM_Composite           *comfine   = (DM_Composite*)fine->data;
1203:   Mat                    *mats;

1208:   DMSetUp(coarse);
1209:   DMSetUp(fine);
1210:   /* use global vectors only for determining matrix layout */
1211:   DMGetGlobalVector(coarse,&gcoarse);
1212:   DMGetGlobalVector(fine,&gfine);
1213:   VecGetLocalSize(gcoarse,&n);
1214:   VecGetLocalSize(gfine,&m);
1215:   VecGetSize(gcoarse,&N);
1216:   VecGetSize(gfine,&M);
1217:   DMRestoreGlobalVector(coarse,&gcoarse);
1218:   DMRestoreGlobalVector(fine,&gfine);

1220:   nDM = comfine->nDM;
1221:   if (nDM != comcoarse->nDM) SETERRQ2(PetscObjectComm((PetscObject)fine),PETSC_ERR_ARG_INCOMP,"Fine DMComposite has %D entries, but coarse has %D",nDM,comcoarse->nDM);
1222:   PetscMalloc(nDM*nDM*sizeof(Mat),&mats);
1223:   PetscMemzero(mats,nDM*nDM*sizeof(Mat));
1224:   if (v) {
1225:     PetscMalloc(nDM*sizeof(Vec),&vecs);
1226:     PetscMemzero(vecs,nDM*sizeof(Vec));
1227:   }

1229:   /* loop over packed objects, handling one at at time */
1230:   for (nextc=comcoarse->next,nextf=comfine->next,i=0; nextc; nextc=nextc->next,nextf=nextf->next,i++) {
1231:     if (!v) {
1232:       DMCreateInterpolation(nextc->dm,nextf->dm,&mats[i*nDM+i],NULL);
1233:     } else {
1234:       DMCreateInterpolation(nextc->dm,nextf->dm,&mats[i*nDM+i],&vecs[i]);
1235:     }
1236:   }
1237:   MatCreateNest(PetscObjectComm((PetscObject)fine),nDM,NULL,nDM,NULL,mats,A);
1238:   if (v) {
1239:     VecCreateNest(PetscObjectComm((PetscObject)fine),nDM,NULL,vecs,v);
1240:   }
1241:   for (i=0; i<nDM*nDM; i++) {MatDestroy(&mats[i]);}
1242:   PetscFree(mats);
1243:   if (v) {
1244:     for (i=0; i<nDM; i++) {VecDestroy(&vecs[i]);}
1245:     PetscFree(vecs);
1246:   }
1247:   return(0);
1248: }

1252: static PetscErrorCode DMGetLocalToGlobalMapping_Composite(DM dm)
1253: {
1254:   DM_Composite           *com = (DM_Composite*)dm->data;
1255:   ISLocalToGlobalMapping *ltogs;
1256:   PetscInt               i;
1257:   PetscErrorCode         ierr;

1260:   /* Set the ISLocalToGlobalMapping on the new matrix */
1261:   DMCompositeGetISLocalToGlobalMappings(dm,&ltogs);
1262:   ISLocalToGlobalMappingConcatenate(PetscObjectComm((PetscObject)dm),com->nDM,ltogs,&dm->ltogmap);
1263:   for (i=0; i<com->nDM; i++) {ISLocalToGlobalMappingDestroy(&ltogs[i]);}
1264:   PetscFree(ltogs);
1265:   return(0);
1266: }


1271: PetscErrorCode  DMCreateColoring_Composite(DM dm,ISColoringType ctype,MatType mtype,ISColoring *coloring)
1272: {
1273:   PetscErrorCode  ierr;
1274:   PetscInt        n,i,cnt;
1275:   ISColoringValue *colors;
1276:   PetscBool       dense  = PETSC_FALSE;
1277:   ISColoringValue maxcol = 0;
1278:   DM_Composite    *com   = (DM_Composite*)dm->data;

1282:   if (ctype == IS_COLORING_GHOSTED) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_SUP,"Only global coloring supported");
1283:   else if (ctype == IS_COLORING_GLOBAL) {
1284:     n = com->n;
1285:   } else SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_ARG_OUTOFRANGE,"Unknown ISColoringType");
1286:   PetscMalloc(n*sizeof(ISColoringValue),&colors); /* freed in ISColoringDestroy() */

1288:   PetscOptionsGetBool(NULL,"-dmcomposite_dense_jacobian",&dense,NULL);
1289:   if (dense) {
1290:     for (i=0; i<n; i++) {
1291:       colors[i] = (ISColoringValue)(com->rstart + i);
1292:     }
1293:     maxcol = com->N;
1294:   } else {
1295:     struct DMCompositeLink *next = com->next;
1296:     PetscMPIInt            rank;

1298:     MPI_Comm_rank(PetscObjectComm((PetscObject)dm),&rank);
1299:     cnt  = 0;
1300:     while (next) {
1301:       ISColoring lcoloring;

1303:       DMCreateColoring(next->dm,IS_COLORING_GLOBAL,mtype,&lcoloring);
1304:       for (i=0; i<lcoloring->N; i++) {
1305:         colors[cnt++] = maxcol + lcoloring->colors[i];
1306:       }
1307:       maxcol += lcoloring->n;
1308:       ISColoringDestroy(&lcoloring);
1309:       next    = next->next;
1310:     }
1311:   }
1312:   ISColoringCreate(PetscObjectComm((PetscObject)dm),maxcol,n,colors,coloring);
1313:   return(0);
1314: }

1318: PetscErrorCode  DMGlobalToLocalBegin_Composite(DM dm,Vec gvec,InsertMode mode,Vec lvec)
1319: {
1320:   PetscErrorCode         ierr;
1321:   struct DMCompositeLink *next;
1322:   PetscInt               cnt = 3;
1323:   PetscMPIInt            rank;
1324:   PetscScalar            *garray,*larray;
1325:   DM_Composite           *com = (DM_Composite*)dm->data;

1330:   next = com->next;
1331:   if (!com->setup) {
1332:     DMSetUp(dm);
1333:   }
1334:   MPI_Comm_rank(PetscObjectComm((PetscObject)dm),&rank);
1335:   VecGetArray(gvec,&garray);
1336:   VecGetArray(lvec,&larray);

1338:   /* loop over packed objects, handling one at at time */
1339:   while (next) {
1340:     Vec      local,global;
1341:     PetscInt N;

1343:     DMGetGlobalVector(next->dm,&global);
1344:     VecGetLocalSize(global,&N);
1345:     VecPlaceArray(global,garray);
1346:     DMGetLocalVector(next->dm,&local);
1347:     VecPlaceArray(local,larray);
1348:     DMGlobalToLocalBegin(next->dm,global,mode,local);
1349:     DMGlobalToLocalEnd(next->dm,global,mode,local);
1350:     VecResetArray(global);
1351:     VecResetArray(local);
1352:     DMRestoreGlobalVector(next->dm,&global);
1353:     DMRestoreGlobalVector(next->dm,&local);
1354:     cnt++;
1355:     larray += next->nlocal;
1356:     next    = next->next;
1357:   }

1359:   VecRestoreArray(gvec,NULL);
1360:   VecRestoreArray(lvec,NULL);
1361:   return(0);
1362: }

1366: PetscErrorCode  DMGlobalToLocalEnd_Composite(DM dm,Vec gvec,InsertMode mode,Vec lvec)
1367: {
1369:   return(0);
1370: }

1372: /*MC
1373:    DMCOMPOSITE = "composite" - A DM object that is used to manage data for a collection of DMs



1377:   Level: intermediate

1379: .seealso: DMType, DMCOMPOSITE, DMDACreate(), DMCreate(), DMSetType(), DMCompositeCreate()
1380: M*/


1385: PETSC_EXTERN PetscErrorCode DMCreate_Composite(DM p)
1386: {
1388:   DM_Composite   *com;

1391:   PetscNewLog(p,DM_Composite,&com);
1392:   p->data   = com;
1393:   PetscObjectChangeTypeName((PetscObject)p,"DMComposite");
1394:   com->n    = 0;
1395:   com->next = NULL;
1396:   com->nDM  = 0;

1398:   p->ops->createglobalvector              = DMCreateGlobalVector_Composite;
1399:   p->ops->createlocalvector               = DMCreateLocalVector_Composite;
1400:   p->ops->getlocaltoglobalmapping         = DMGetLocalToGlobalMapping_Composite;
1401:   p->ops->getlocaltoglobalmappingblock    = 0;
1402:   p->ops->createfieldis                   = DMCreateFieldIS_Composite;
1403:   p->ops->createfielddecomposition        = DMCreateFieldDecomposition_Composite;
1404:   p->ops->refine                          = DMRefine_Composite;
1405:   p->ops->coarsen                         = DMCoarsen_Composite;
1406:   p->ops->createinterpolation             = DMCreateInterpolation_Composite;
1407:   p->ops->creatematrix                    = DMCreateMatrix_Composite;
1408:   p->ops->getcoloring                     = DMCreateColoring_Composite;
1409:   p->ops->globaltolocalbegin              = DMGlobalToLocalBegin_Composite;
1410:   p->ops->globaltolocalend                = DMGlobalToLocalEnd_Composite;
1411:   p->ops->destroy                         = DMDestroy_Composite;
1412:   p->ops->view                            = DMView_Composite;
1413:   p->ops->setup                           = DMSetUp_Composite;
1414:   return(0);
1415: }

1419: /*@C
1420:     DMCompositeCreate - Creates a vector packer, used to generate "composite"
1421:       vectors made up of several subvectors.

1423:     Collective on MPI_Comm

1425:     Input Parameter:
1426: .   comm - the processors that will share the global vector

1428:     Output Parameters:
1429: .   packer - the packer object

1431:     Level: advanced

1433: .seealso DMDestroy(), DMCompositeAddDM(), DMCompositeScatter(),
1434:          DMCompositeGather(), DMCreateGlobalVector(), DMCompositeGetISLocalToGlobalMappings(), DMCompositeGetAccess()
1435:          DMCompositeGetLocalVectors(), DMCompositeRestoreLocalVectors(), DMCompositeGetEntries()

1437: @*/
1438: PetscErrorCode  DMCompositeCreate(MPI_Comm comm,DM *packer)
1439: {

1444:   DMCreate(comm,packer);
1445:   DMSetType(*packer,DMCOMPOSITE);
1446:   return(0);
1447: }