Actual source code: isltog.c


  2: #include <petsc/private/isimpl.h>
  3: #include <petsc/private/hashmapi.h>
  4: #include <petscsf.h>
  5: #include <petscviewer.h>

  7: PetscClassId IS_LTOGM_CLASSID;
  8: static PetscErrorCode  ISLocalToGlobalMappingGetBlockInfo_Private(ISLocalToGlobalMapping,PetscInt*,PetscInt**,PetscInt**,PetscInt***);

 10: typedef struct {
 11:   PetscInt *globals;
 12: } ISLocalToGlobalMapping_Basic;

 14: typedef struct {
 15:   PetscHMapI globalht;
 16: } ISLocalToGlobalMapping_Hash;

 18: /*@C
 19:   ISGetPointRange - Returns a description of the points in an IS suitable for traversal

 21:   Not collective

 23:   Input Parameter:
 24: . pointIS - The IS object

 26:   Output Parameters:
 27: + pStart - The first index, see notes
 28: . pEnd   - One past the last index, see notes
 29: - points - The indices, see notes

 31:   Notes:
 32:   If the IS contains contiguous indices in an ISSTRIDE, then the indices are contained in [pStart, pEnd) and points = NULL. Otherwise, pStart = 0, pEnd = numIndices, and points is an array of the indices. This supports the following pattern
 33: $ ISGetPointRange(is, &pStart, &pEnd, &points);
 34: $ for (p = pStart; p < pEnd; ++p) {
 35: $   const PetscInt point = points ? points[p] : p;
 36: $ }
 37: $ ISRestorePointRange(is, &pstart, &pEnd, &points);

 39:   Level: intermediate

 41: .seealso: ISRestorePointRange(), ISGetPointSubrange(), ISGetIndices(), ISCreateStride()
 42: @*/
 43: PetscErrorCode ISGetPointRange(IS pointIS, PetscInt *pStart, PetscInt *pEnd, const PetscInt **points)
 44: {
 45:   PetscInt       numCells, step = 1;
 46:   PetscBool      isStride;

 49:   *pStart = 0;
 50:   *points = NULL;
 51:   ISGetLocalSize(pointIS, &numCells);
 52:   PetscObjectTypeCompare((PetscObject) pointIS, ISSTRIDE, &isStride);
 53:   if (isStride) ISStrideGetInfo(pointIS, pStart, &step);
 54:   *pEnd   = *pStart + numCells;
 55:   if (!isStride || step != 1) ISGetIndices(pointIS, points);
 56:   return 0;
 57: }

 59: /*@C
 60:   ISRestorePointRange - Destroys the traversal description

 62:   Not collective

 64:   Input Parameters:
 65: + pointIS - The IS object
 66: . pStart  - The first index, from ISGetPointRange()
 67: . pEnd    - One past the last index, from ISGetPointRange()
 68: - points  - The indices, from ISGetPointRange()

 70:   Notes:
 71:   If the IS contains contiguous indices in an ISSTRIDE, then the indices are contained in [pStart, pEnd) and points = NULL. Otherwise, pStart = 0, pEnd = numIndices, and points is an array of the indices. This supports the following pattern
 72: $ ISGetPointRange(is, &pStart, &pEnd, &points);
 73: $ for (p = pStart; p < pEnd; ++p) {
 74: $   const PetscInt point = points ? points[p] : p;
 75: $ }
 76: $ ISRestorePointRange(is, &pstart, &pEnd, &points);

 78:   Level: intermediate

 80: .seealso: ISGetPointRange(), ISGetPointSubrange(), ISGetIndices(), ISCreateStride()
 81: @*/
 82: PetscErrorCode ISRestorePointRange(IS pointIS, PetscInt *pStart, PetscInt *pEnd, const PetscInt **points)
 83: {
 84:   PetscInt       step = 1;
 85:   PetscBool      isStride;

 88:   PetscObjectTypeCompare((PetscObject) pointIS, ISSTRIDE, &isStride);
 89:   if (isStride) ISStrideGetInfo(pointIS, pStart, &step);
 90:   if (!isStride || step != 1) ISGetIndices(pointIS, points);
 91:   return 0;
 92: }

 94: /*@C
 95:   ISGetPointSubrange - Configures the input IS to be a subrange for the traversal information given

 97:   Not collective

 99:   Input Parameters:
100: + subpointIS - The IS object to be configured
101: . pStar   t  - The first index of the subrange
102: . pEnd       - One past the last index for the subrange
103: - points     - The indices for the entire range, from ISGetPointRange()

105:   Output Parameters:
106: . subpointIS - The IS object now configured to be a subrange

108:   Notes:
109:   The input IS will now respond properly to calls to ISGetPointRange() and return the subrange.

111:   Level: intermediate

113: .seealso: ISGetPointRange(), ISRestorePointRange(), ISGetIndices(), ISCreateStride()
114: @*/
115: PetscErrorCode ISGetPointSubrange(IS subpointIS, PetscInt pStart, PetscInt pEnd, const PetscInt *points)
116: {
118:   if (points) {
119:     ISSetType(subpointIS, ISGENERAL);
120:     ISGeneralSetIndices(subpointIS, pEnd-pStart, &points[pStart], PETSC_USE_POINTER);
121:   } else {
122:     ISSetType(subpointIS, ISSTRIDE);
123:     ISStrideSetStride(subpointIS, pEnd-pStart, pStart, 1);
124:   }
125:   return 0;
126: }

128: /* -----------------------------------------------------------------------------------------*/

130: /*
131:     Creates the global mapping information in the ISLocalToGlobalMapping structure

133:     If the user has not selected how to handle the global to local mapping then use HASH for "large" problems
134: */
135: static PetscErrorCode ISGlobalToLocalMappingSetUp(ISLocalToGlobalMapping mapping)
136: {
137:   PetscInt       i,*idx = mapping->indices,n = mapping->n,end,start;

139:   if (mapping->data) return 0;
140:   end   = 0;
141:   start = PETSC_MAX_INT;

143:   for (i=0; i<n; i++) {
144:     if (idx[i] < 0) continue;
145:     if (idx[i] < start) start = idx[i];
146:     if (idx[i] > end)   end   = idx[i];
147:   }
148:   if (start > end) {start = 0; end = -1;}
149:   mapping->globalstart = start;
150:   mapping->globalend   = end;
151:   if (!((PetscObject)mapping)->type_name) {
152:     if ((end - start) > PetscMax(4*n,1000000)) {
153:       ISLocalToGlobalMappingSetType(mapping,ISLOCALTOGLOBALMAPPINGHASH);
154:     } else {
155:       ISLocalToGlobalMappingSetType(mapping,ISLOCALTOGLOBALMAPPINGBASIC);
156:     }
157:   }
158:   if (mapping->ops->globaltolocalmappingsetup) (*mapping->ops->globaltolocalmappingsetup)(mapping);
159:   return 0;
160: }

162: static PetscErrorCode ISGlobalToLocalMappingSetUp_Basic(ISLocalToGlobalMapping mapping)
163: {
164:   PetscInt                    i,*idx = mapping->indices,n = mapping->n,end,start,*globals;
165:   ISLocalToGlobalMapping_Basic *map;

167:   start            = mapping->globalstart;
168:   end              = mapping->globalend;
169:   PetscNew(&map);
170:   PetscMalloc1(end-start+2,&globals);
171:   map->globals     = globals;
172:   for (i=0; i<end-start+1; i++) globals[i] = -1;
173:   for (i=0; i<n; i++) {
174:     if (idx[i] < 0) continue;
175:     globals[idx[i] - start] = i;
176:   }
177:   mapping->data = (void*)map;
178:   PetscLogObjectMemory((PetscObject)mapping,(end-start+1)*sizeof(PetscInt));
179:   return 0;
180: }

182: static PetscErrorCode ISGlobalToLocalMappingSetUp_Hash(ISLocalToGlobalMapping mapping)
183: {
184:   PetscInt                    i,*idx = mapping->indices,n = mapping->n;
185:   ISLocalToGlobalMapping_Hash *map;

187:   PetscNew(&map);
188:   PetscHMapICreate(&map->globalht);
189:   for (i=0; i<n; i++) {
190:     if (idx[i] < 0) continue;
191:     PetscHMapISet(map->globalht,idx[i],i);
192:   }
193:   mapping->data = (void*)map;
194:   PetscLogObjectMemory((PetscObject)mapping,2*n*sizeof(PetscInt));
195:   return 0;
196: }

198: static PetscErrorCode ISLocalToGlobalMappingDestroy_Basic(ISLocalToGlobalMapping mapping)
199: {
200:   ISLocalToGlobalMapping_Basic *map  = (ISLocalToGlobalMapping_Basic *)mapping->data;

202:   if (!map) return 0;
203:   PetscFree(map->globals);
204:   PetscFree(mapping->data);
205:   return 0;
206: }

208: static PetscErrorCode ISLocalToGlobalMappingDestroy_Hash(ISLocalToGlobalMapping mapping)
209: {
210:   ISLocalToGlobalMapping_Hash *map  = (ISLocalToGlobalMapping_Hash*)mapping->data;

212:   if (!map) return 0;
213:   PetscHMapIDestroy(&map->globalht);
214:   PetscFree(mapping->data);
215:   return 0;
216: }

218: #define GTOLTYPE _Basic
219: #define GTOLNAME _Basic
220: #define GTOLBS mapping->bs
221: #define GTOL(g, local) do {                  \
222:     local = map->globals[g/bs - start];      \
223:     if (local >= 0) local = bs*local + (g % bs); \
224:   } while (0)

226: #include <../src/vec/is/utils/isltog.h>

228: #define GTOLTYPE _Basic
229: #define GTOLNAME Block_Basic
230: #define GTOLBS 1
231: #define GTOL(g, local) do {                  \
232:     local = map->globals[g - start];         \
233:   } while (0)
234: #include <../src/vec/is/utils/isltog.h>

236: #define GTOLTYPE _Hash
237: #define GTOLNAME _Hash
238: #define GTOLBS mapping->bs
239: #define GTOL(g, local) do {                         \
240:     (void)PetscHMapIGet(map->globalht,g/bs,&local); \
241:     if (local >= 0) local = bs*local + (g % bs);   \
242:    } while (0)
243: #include <../src/vec/is/utils/isltog.h>

245: #define GTOLTYPE _Hash
246: #define GTOLNAME Block_Hash
247: #define GTOLBS 1
248: #define GTOL(g, local) do {                         \
249:     (void)PetscHMapIGet(map->globalht,g,&local);    \
250:   } while (0)
251: #include <../src/vec/is/utils/isltog.h>

253: /*@
254:     ISLocalToGlobalMappingDuplicate - Duplicates the local to global mapping object

256:     Not Collective

258:     Input Parameter:
259: .   ltog - local to global mapping

261:     Output Parameter:
262: .   nltog - the duplicated local to global mapping

264:     Level: advanced

266: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreate()
267: @*/
268: PetscErrorCode  ISLocalToGlobalMappingDuplicate(ISLocalToGlobalMapping ltog,ISLocalToGlobalMapping* nltog)
269: {
270:   ISLocalToGlobalMappingType l2gtype;

273:   ISLocalToGlobalMappingCreate(PetscObjectComm((PetscObject)ltog),ltog->bs,ltog->n,ltog->indices,PETSC_COPY_VALUES,nltog);
274:   ISLocalToGlobalMappingGetType(ltog,&l2gtype);
275:   ISLocalToGlobalMappingSetType(*nltog,l2gtype);
276:   return 0;
277: }

279: /*@
280:     ISLocalToGlobalMappingGetSize - Gets the local size of a local to global mapping

282:     Not Collective

284:     Input Parameter:
285: .   ltog - local to global mapping

287:     Output Parameter:
288: .   n - the number of entries in the local mapping, ISLocalToGlobalMappingGetIndices() returns an array of this length

290:     Level: advanced

292: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreate()
293: @*/
294: PetscErrorCode  ISLocalToGlobalMappingGetSize(ISLocalToGlobalMapping mapping,PetscInt *n)
295: {
298:   *n = mapping->bs*mapping->n;
299:   return 0;
300: }

302: /*@C
303:    ISLocalToGlobalMappingViewFromOptions - View from Options

305:    Collective on ISLocalToGlobalMapping

307:    Input Parameters:
308: +  A - the local to global mapping object
309: .  obj - Optional object
310: -  name - command line option

312:    Level: intermediate
313: .seealso:  ISLocalToGlobalMapping, ISLocalToGlobalMappingView, PetscObjectViewFromOptions(), ISLocalToGlobalMappingCreate()
314: @*/
315: PetscErrorCode  ISLocalToGlobalMappingViewFromOptions(ISLocalToGlobalMapping A,PetscObject obj,const char name[])
316: {
318:   PetscObjectViewFromOptions((PetscObject)A,obj,name);
319:   return 0;
320: }

322: /*@C
323:     ISLocalToGlobalMappingView - View a local to global mapping

325:     Not Collective

327:     Input Parameters:
328: +   ltog - local to global mapping
329: -   viewer - viewer

331:     Level: advanced

333: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreate()
334: @*/
335: PetscErrorCode  ISLocalToGlobalMappingView(ISLocalToGlobalMapping mapping,PetscViewer viewer)
336: {
337:   PetscInt       i;
338:   PetscMPIInt    rank;
339:   PetscBool      iascii;

342:   if (!viewer) {
343:     PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)mapping),&viewer);
344:   }

347:   MPI_Comm_rank(PetscObjectComm((PetscObject)mapping),&rank);
348:   PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);
349:   if (iascii) {
350:     PetscObjectPrintClassNamePrefixType((PetscObject)mapping,viewer);
351:     PetscViewerASCIIPushSynchronized(viewer);
352:     for (i=0; i<mapping->n; i++) {
353:       PetscViewerASCIISynchronizedPrintf(viewer,"[%d] %" PetscInt_FMT " %" PetscInt_FMT "\n",rank,i,mapping->indices[i]);
354:     }
355:     PetscViewerFlush(viewer);
356:     PetscViewerASCIIPopSynchronized(viewer);
357:   }
358:   return 0;
359: }

361: /*@
362:     ISLocalToGlobalMappingCreateIS - Creates a mapping between a local (0 to n)
363:     ordering and a global parallel ordering.

365:     Not collective

367:     Input Parameter:
368: .   is - index set containing the global numbers for each local number

370:     Output Parameter:
371: .   mapping - new mapping data structure

373:     Notes:
374:     the block size of the IS determines the block size of the mapping
375:     Level: advanced

377: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreate(), ISLocalToGlobalMappingSetFromOptions()
378: @*/
379: PetscErrorCode  ISLocalToGlobalMappingCreateIS(IS is,ISLocalToGlobalMapping *mapping)
380: {
381:   PetscInt       n,bs;
382:   const PetscInt *indices;
383:   MPI_Comm       comm;
384:   PetscBool      isblock;


389:   PetscObjectGetComm((PetscObject)is,&comm);
390:   ISGetLocalSize(is,&n);
391:   PetscObjectTypeCompare((PetscObject)is,ISBLOCK,&isblock);
392:   if (!isblock) {
393:     ISGetIndices(is,&indices);
394:     ISLocalToGlobalMappingCreate(comm,1,n,indices,PETSC_COPY_VALUES,mapping);
395:     ISRestoreIndices(is,&indices);
396:   } else {
397:     ISGetBlockSize(is,&bs);
398:     ISBlockGetIndices(is,&indices);
399:     ISLocalToGlobalMappingCreate(comm,bs,n/bs,indices,PETSC_COPY_VALUES,mapping);
400:     ISBlockRestoreIndices(is,&indices);
401:   }
402:   return 0;
403: }

405: /*@C
406:     ISLocalToGlobalMappingCreateSF - Creates a mapping between a local (0 to n)
407:     ordering and a global parallel ordering.

409:     Collective

411:     Input Parameters:
412: +   sf - star forest mapping contiguous local indices to (rank, offset)
413: -   start - first global index on this process, or PETSC_DECIDE to compute contiguous global numbering automatically

415:     Output Parameter:
416: .   mapping - new mapping data structure

418:     Level: advanced

420:     Notes:
421:     If any processor calls this with start = PETSC_DECIDE then all processors must, otherwise the program will hang.

423: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreate(), ISLocalToGlobalMappingCreateIS(), ISLocalToGlobalMappingSetFromOptions()
424: @*/
425: PetscErrorCode ISLocalToGlobalMappingCreateSF(PetscSF sf,PetscInt start,ISLocalToGlobalMapping *mapping)
426: {
427:   PetscInt       i,maxlocal,nroots,nleaves,*globals,*ltog;
428:   const PetscInt *ilocal;
429:   MPI_Comm       comm;


434:   PetscObjectGetComm((PetscObject)sf,&comm);
435:   PetscSFGetGraph(sf,&nroots,&nleaves,&ilocal,NULL);
436:   if (start == PETSC_DECIDE) {
437:     start = 0;
438:     MPI_Exscan(&nroots,&start,1,MPIU_INT,MPI_SUM,comm);
440:   if (ilocal) {
441:     for (i=0,maxlocal=0; i<nleaves; i++) maxlocal = PetscMax(maxlocal,ilocal[i]+1);
442:   }
443:   else maxlocal = nleaves;
444:   PetscMalloc1(nroots,&globals);
445:   PetscMalloc1(maxlocal,&ltog);
446:   for (i=0; i<nroots; i++) globals[i] = start + i;
447:   for (i=0; i<maxlocal; i++) ltog[i] = -1;
448:   PetscSFBcastBegin(sf,MPIU_INT,globals,ltog,MPI_REPLACE);
449:   PetscSFBcastEnd(sf,MPIU_INT,globals,ltog,MPI_REPLACE);
450:   ISLocalToGlobalMappingCreate(comm,1,maxlocal,ltog,PETSC_OWN_POINTER,mapping);
451:   PetscFree(globals);
452:   return 0;
453: }

455: /*@
456:     ISLocalToGlobalMappingSetBlockSize - Sets the blocksize of the mapping

458:     Not collective

460:     Input Parameters:
461: +   mapping - mapping data structure
462: -   bs - the blocksize

464:     Level: advanced

466: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreateIS()
467: @*/
468: PetscErrorCode  ISLocalToGlobalMappingSetBlockSize(ISLocalToGlobalMapping mapping,PetscInt bs)
469: {
470:   PetscInt       *nid;
471:   const PetscInt *oid;
472:   PetscInt       i,cn,on,obs,nn;

476:   if (bs == mapping->bs) return 0;
477:   on  = mapping->n;
478:   obs = mapping->bs;
479:   oid = mapping->indices;
480:   nn  = (on*obs)/bs;

483:   PetscMalloc1(nn,&nid);
484:   ISLocalToGlobalMappingGetIndices(mapping,&oid);
485:   for (i=0;i<nn;i++) {
486:     PetscInt j;
487:     for (j=0,cn=0;j<bs-1;j++) {
488:       if (oid[i*bs+j] < 0) { cn++; continue; }
490:     }
491:     if (oid[i*bs+j] < 0) cn++;
492:     if (cn) {
494:       nid[i] = -1;
495:     } else {
496:       nid[i] = oid[i*bs]/bs;
497:     }
498:   }
499:   ISLocalToGlobalMappingRestoreIndices(mapping,&oid);

501:   mapping->n           = nn;
502:   mapping->bs          = bs;
503:   PetscFree(mapping->indices);
504:   mapping->indices     = nid;
505:   mapping->globalstart = 0;
506:   mapping->globalend   = 0;

508:   /* reset the cached information */
509:   PetscFree(mapping->info_procs);
510:   PetscFree(mapping->info_numprocs);
511:   if (mapping->info_indices) {
512:     PetscInt i;

514:     PetscFree((mapping->info_indices)[0]);
515:     for (i=1; i<mapping->info_nproc; i++) {
516:       PetscFree(mapping->info_indices[i]);
517:     }
518:     PetscFree(mapping->info_indices);
519:   }
520:   mapping->info_cached = PETSC_FALSE;

522:   if (mapping->ops->destroy) {
523:     (*mapping->ops->destroy)(mapping);
524:   }
525:   return 0;
526: }

528: /*@
529:     ISLocalToGlobalMappingGetBlockSize - Gets the blocksize of the mapping
530:     ordering and a global parallel ordering.

532:     Not Collective

534:     Input Parameters:
535: .   mapping - mapping data structure

537:     Output Parameter:
538: .   bs - the blocksize

540:     Level: advanced

542: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreateIS()
543: @*/
544: PetscErrorCode  ISLocalToGlobalMappingGetBlockSize(ISLocalToGlobalMapping mapping,PetscInt *bs)
545: {
547:   *bs = mapping->bs;
548:   return 0;
549: }

551: /*@
552:     ISLocalToGlobalMappingCreate - Creates a mapping between a local (0 to n)
553:     ordering and a global parallel ordering.

555:     Not Collective, but communicator may have more than one process

557:     Input Parameters:
558: +   comm - MPI communicator
559: .   bs - the block size
560: .   n - the number of local elements divided by the block size, or equivalently the number of block indices
561: .   indices - the global index for each local element, these do not need to be in increasing order (sorted), these values should not be scaled (i.e. multiplied) by the blocksize bs
562: -   mode - see PetscCopyMode

564:     Output Parameter:
565: .   mapping - new mapping data structure

567:     Notes:
568:     There is one integer value in indices per block and it represents the actual indices bs*idx + j, where j=0,..,bs-1

570:     For "small" problems when using ISGlobalToLocalMappingApply() and ISGlobalToLocalMappingApplyBlock(), the ISLocalToGlobalMappingType of ISLOCALTOGLOBALMAPPINGBASIC will be used;
571:     this uses more memory but is faster; this approach is not scalable for extremely large mappings. For large problems ISLOCALTOGLOBALMAPPINGHASH is used, this is scalable.
572:     Use ISLocalToGlobalMappingSetType() or call ISLocalToGlobalMappingSetFromOptions() with the option -islocaltoglobalmapping_type <basic,hash> to control which is used.

574:     Level: advanced

576: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreateIS(), ISLocalToGlobalMappingSetFromOptions(), ISLOCALTOGLOBALMAPPINGBASIC, ISLOCALTOGLOBALMAPPINGHASH
577:           ISLocalToGlobalMappingSetType(), ISLocalToGlobalMappingType
578: @*/
579: PetscErrorCode  ISLocalToGlobalMappingCreate(MPI_Comm comm,PetscInt bs,PetscInt n,const PetscInt indices[],PetscCopyMode mode,ISLocalToGlobalMapping *mapping)
580: {
581:   PetscInt       *in;


586:   *mapping = NULL;
587:   ISInitializePackage();

589:   PetscHeaderCreate(*mapping,IS_LTOGM_CLASSID,"ISLocalToGlobalMapping","Local to global mapping","IS",comm,ISLocalToGlobalMappingDestroy,ISLocalToGlobalMappingView);
590:   (*mapping)->n  = n;
591:   (*mapping)->bs = bs;
592:   if (mode == PETSC_COPY_VALUES) {
593:     PetscMalloc1(n,&in);
594:     PetscArraycpy(in,indices,n);
595:     (*mapping)->indices = in;
596:     (*mapping)->dealloc_indices = PETSC_TRUE;
597:     PetscLogObjectMemory((PetscObject)*mapping,n*sizeof(PetscInt));
598:   } else if (mode == PETSC_OWN_POINTER) {
599:     (*mapping)->indices = (PetscInt*)indices;
600:     (*mapping)->dealloc_indices = PETSC_TRUE;
601:     PetscLogObjectMemory((PetscObject)*mapping,n*sizeof(PetscInt));
602:   } else if (mode == PETSC_USE_POINTER) {
603:     (*mapping)->indices = (PetscInt*)indices;
604:   }
605:   else SETERRQ(comm,PETSC_ERR_ARG_OUTOFRANGE,"Invalid mode %d", mode);
606:   return 0;
607: }

609: PetscFunctionList ISLocalToGlobalMappingList = NULL;

611: /*@
612:    ISLocalToGlobalMappingSetFromOptions - Set mapping options from the options database.

614:    Not collective

616:    Input Parameters:
617: .  mapping - mapping data structure

619:    Level: advanced

621: @*/
622: PetscErrorCode ISLocalToGlobalMappingSetFromOptions(ISLocalToGlobalMapping mapping)
623: {
624:   PetscErrorCode             ierr;
625:   char                       type[256];
626:   ISLocalToGlobalMappingType defaulttype = "Not set";
627:   PetscBool                  flg;

630:   ISLocalToGlobalMappingRegisterAll();
631:   PetscObjectOptionsBegin((PetscObject)mapping);
632:   PetscOptionsFList("-islocaltoglobalmapping_type","ISLocalToGlobalMapping method","ISLocalToGlobalMappingSetType",ISLocalToGlobalMappingList,(char*)(((PetscObject)mapping)->type_name) ? ((PetscObject)mapping)->type_name : defaulttype,type,256,&flg);
633:   if (flg) {
634:     ISLocalToGlobalMappingSetType(mapping,type);
635:   }
636:   PetscOptionsEnd();
637:   return 0;
638: }

640: /*@
641:    ISLocalToGlobalMappingDestroy - Destroys a mapping between a local (0 to n)
642:    ordering and a global parallel ordering.

644:    Note Collective

646:    Input Parameters:
647: .  mapping - mapping data structure

649:    Level: advanced

651: .seealso: ISLocalToGlobalMappingCreate()
652: @*/
653: PetscErrorCode  ISLocalToGlobalMappingDestroy(ISLocalToGlobalMapping *mapping)
654: {
655:   if (!*mapping) return 0;
657:   if (--((PetscObject)(*mapping))->refct > 0) {*mapping = NULL;return 0;}
658:   if ((*mapping)->dealloc_indices) {
659:     PetscFree((*mapping)->indices);
660:   }
661:   PetscFree((*mapping)->info_procs);
662:   PetscFree((*mapping)->info_numprocs);
663:   if ((*mapping)->info_indices) {
664:     PetscInt i;

666:     PetscFree(((*mapping)->info_indices)[0]);
667:     for (i=1; i<(*mapping)->info_nproc; i++) {
668:       PetscFree(((*mapping)->info_indices)[i]);
669:     }
670:     PetscFree((*mapping)->info_indices);
671:   }
672:   if ((*mapping)->info_nodei) {
673:     PetscFree(((*mapping)->info_nodei)[0]);
674:   }
675:   PetscFree2((*mapping)->info_nodec,(*mapping)->info_nodei);
676:   if ((*mapping)->ops->destroy) {
677:     (*(*mapping)->ops->destroy)(*mapping);
678:   }
679:   PetscHeaderDestroy(mapping);
680:   *mapping = NULL;
681:   return 0;
682: }

684: /*@
685:     ISLocalToGlobalMappingApplyIS - Creates from an IS in the local numbering
686:     a new index set using the global numbering defined in an ISLocalToGlobalMapping
687:     context.

689:     Collective on is

691:     Input Parameters:
692: +   mapping - mapping between local and global numbering
693: -   is - index set in local numbering

695:     Output Parameters:
696: .   newis - index set in global numbering

698:     Notes:
699:     The output IS will have the same communicator of the input IS.

701:     Level: advanced

703: .seealso: ISLocalToGlobalMappingApply(), ISLocalToGlobalMappingCreate(),
704:           ISLocalToGlobalMappingDestroy(), ISGlobalToLocalMappingApply()
705: @*/
706: PetscErrorCode  ISLocalToGlobalMappingApplyIS(ISLocalToGlobalMapping mapping,IS is,IS *newis)
707: {
708:   PetscInt       n,*idxout;
709:   const PetscInt *idxin;


715:   ISGetLocalSize(is,&n);
716:   ISGetIndices(is,&idxin);
717:   PetscMalloc1(n,&idxout);
718:   ISLocalToGlobalMappingApply(mapping,n,idxin,idxout);
719:   ISRestoreIndices(is,&idxin);
720:   ISCreateGeneral(PetscObjectComm((PetscObject)is),n,idxout,PETSC_OWN_POINTER,newis);
721:   return 0;
722: }

724: /*@
725:    ISLocalToGlobalMappingApply - Takes a list of integers in a local numbering
726:    and converts them to the global numbering.

728:    Not collective

730:    Input Parameters:
731: +  mapping - the local to global mapping context
732: .  N - number of integers
733: -  in - input indices in local numbering

735:    Output Parameter:
736: .  out - indices in global numbering

738:    Notes:
739:    The in and out array parameters may be identical.

741:    Level: advanced

743: .seealso: ISLocalToGlobalMappingApplyBlock(), ISLocalToGlobalMappingCreate(),ISLocalToGlobalMappingDestroy(),
744:           ISLocalToGlobalMappingApplyIS(),AOCreateBasic(),AOApplicationToPetsc(),
745:           AOPetscToApplication(), ISGlobalToLocalMappingApply()

747: @*/
748: PetscErrorCode ISLocalToGlobalMappingApply(ISLocalToGlobalMapping mapping,PetscInt N,const PetscInt in[],PetscInt out[])
749: {
750:   PetscInt i,bs,Nmax;

753:   bs   = mapping->bs;
754:   Nmax = bs*mapping->n;
755:   if (bs == 1) {
756:     const PetscInt *idx = mapping->indices;
757:     for (i=0; i<N; i++) {
758:       if (in[i] < 0) {
759:         out[i] = in[i];
760:         continue;
761:       }
763:       out[i] = idx[in[i]];
764:     }
765:   } else {
766:     const PetscInt *idx = mapping->indices;
767:     for (i=0; i<N; i++) {
768:       if (in[i] < 0) {
769:         out[i] = in[i];
770:         continue;
771:       }
773:       out[i] = idx[in[i]/bs]*bs + (in[i] % bs);
774:     }
775:   }
776:   return 0;
777: }

779: /*@
780:    ISLocalToGlobalMappingApplyBlock - Takes a list of integers in a local block numbering and converts them to the global block numbering

782:    Not collective

784:    Input Parameters:
785: +  mapping - the local to global mapping context
786: .  N - number of integers
787: -  in - input indices in local block numbering

789:    Output Parameter:
790: .  out - indices in global block numbering

792:    Notes:
793:    The in and out array parameters may be identical.

795:    Example:
796:      If the index values are {0,1,6,7} set with a call to ISLocalToGlobalMappingCreate(PETSC_COMM_SELF,2,2,{0,3}) then the mapping applied to 0
797:      (the first block) would produce 0 and the mapping applied to 1 (the second block) would produce 3.

799:    Level: advanced

801: .seealso: ISLocalToGlobalMappingApply(), ISLocalToGlobalMappingCreate(),ISLocalToGlobalMappingDestroy(),
802:           ISLocalToGlobalMappingApplyIS(),AOCreateBasic(),AOApplicationToPetsc(),
803:           AOPetscToApplication(), ISGlobalToLocalMappingApply()

805: @*/
806: PetscErrorCode ISLocalToGlobalMappingApplyBlock(ISLocalToGlobalMapping mapping,PetscInt N,const PetscInt in[],PetscInt out[])
807: {
808:   PetscInt       i,Nmax;
809:   const PetscInt *idx;

812:   Nmax = mapping->n;
813:   idx = mapping->indices;
814:   for (i=0; i<N; i++) {
815:     if (in[i] < 0) {
816:       out[i] = in[i];
817:       continue;
818:     }
820:     out[i] = idx[in[i]];
821:   }
822:   return 0;
823: }

825: /*@
826:     ISGlobalToLocalMappingApply - Provides the local numbering for a list of integers
827:     specified with a global numbering.

829:     Not collective

831:     Input Parameters:
832: +   mapping - mapping between local and global numbering
833: .   type - IS_GTOLM_MASK - maps global indices with no local value to -1 in the output list (i.e., mask them)
834:            IS_GTOLM_DROP - drops the indices with no local value from the output list
835: .   n - number of global indices to map
836: -   idx - global indices to map

838:     Output Parameters:
839: +   nout - number of indices in output array (if type == IS_GTOLM_MASK then nout = n)
840: -   idxout - local index of each global index, one must pass in an array long enough
841:              to hold all the indices. You can call ISGlobalToLocalMappingApply() with
842:              idxout == NULL to determine the required length (returned in nout)
843:              and then allocate the required space and call ISGlobalToLocalMappingApply()
844:              a second time to set the values.

846:     Notes:
847:     Either nout or idxout may be NULL. idx and idxout may be identical.

849:     For "small" problems when using ISGlobalToLocalMappingApply() and ISGlobalToLocalMappingApplyBlock(), the ISLocalToGlobalMappingType of ISLOCALTOGLOBALMAPPINGBASIC will be used;
850:     this uses more memory but is faster; this approach is not scalable for extremely large mappings. For large problems ISLOCALTOGLOBALMAPPINGHASH is used, this is scalable.
851:     Use ISLocalToGlobalMappingSetType() or call ISLocalToGlobalMappingSetFromOptions() with the option -islocaltoglobalmapping_type <basic,hash> to control which is used.

853:     Level: advanced

855:     Developer Note: The manual page states that idx and idxout may be identical but the calling
856:        sequence declares idx as const so it cannot be the same as idxout.

858: .seealso: ISLocalToGlobalMappingApply(), ISGlobalToLocalMappingApplyBlock(), ISLocalToGlobalMappingCreate(),
859:           ISLocalToGlobalMappingDestroy()
860: @*/
861: PetscErrorCode  ISGlobalToLocalMappingApply(ISLocalToGlobalMapping mapping,ISGlobalToLocalMappingMode type,PetscInt n,const PetscInt idx[],PetscInt *nout,PetscInt idxout[])
862: {
864:   if (!mapping->data) {
865:     ISGlobalToLocalMappingSetUp(mapping);
866:   }
867:   (*mapping->ops->globaltolocalmappingapply)(mapping,type,n,idx,nout,idxout);
868:   return 0;
869: }

871: /*@
872:     ISGlobalToLocalMappingApplyIS - Creates from an IS in the global numbering
873:     a new index set using the local numbering defined in an ISLocalToGlobalMapping
874:     context.

876:     Not collective

878:     Input Parameters:
879: +   mapping - mapping between local and global numbering
880: .   type - IS_GTOLM_MASK - maps global indices with no local value to -1 in the output list (i.e., mask them)
881:            IS_GTOLM_DROP - drops the indices with no local value from the output list
882: -   is - index set in global numbering

884:     Output Parameters:
885: .   newis - index set in local numbering

887:     Notes:
888:     The output IS will be sequential, as it encodes a purely local operation

890:     Level: advanced

892: .seealso: ISGlobalToLocalMappingApply(), ISLocalToGlobalMappingCreate(),
893:           ISLocalToGlobalMappingDestroy()
894: @*/
895: PetscErrorCode  ISGlobalToLocalMappingApplyIS(ISLocalToGlobalMapping mapping,ISGlobalToLocalMappingMode type,IS is,IS *newis)
896: {
897:   PetscInt       n,nout,*idxout;
898:   const PetscInt *idxin;


904:   ISGetLocalSize(is,&n);
905:   ISGetIndices(is,&idxin);
906:   if (type == IS_GTOLM_MASK) {
907:     PetscMalloc1(n,&idxout);
908:   } else {
909:     ISGlobalToLocalMappingApply(mapping,type,n,idxin,&nout,NULL);
910:     PetscMalloc1(nout,&idxout);
911:   }
912:   ISGlobalToLocalMappingApply(mapping,type,n,idxin,&nout,idxout);
913:   ISRestoreIndices(is,&idxin);
914:   ISCreateGeneral(PETSC_COMM_SELF,nout,idxout,PETSC_OWN_POINTER,newis);
915:   return 0;
916: }

918: /*@
919:     ISGlobalToLocalMappingApplyBlock - Provides the local block numbering for a list of integers
920:     specified with a block global numbering.

922:     Not collective

924:     Input Parameters:
925: +   mapping - mapping between local and global numbering
926: .   type - IS_GTOLM_MASK - maps global indices with no local value to -1 in the output list (i.e., mask them)
927:            IS_GTOLM_DROP - drops the indices with no local value from the output list
928: .   n - number of global indices to map
929: -   idx - global indices to map

931:     Output Parameters:
932: +   nout - number of indices in output array (if type == IS_GTOLM_MASK then nout = n)
933: -   idxout - local index of each global index, one must pass in an array long enough
934:              to hold all the indices. You can call ISGlobalToLocalMappingApplyBlock() with
935:              idxout == NULL to determine the required length (returned in nout)
936:              and then allocate the required space and call ISGlobalToLocalMappingApplyBlock()
937:              a second time to set the values.

939:     Notes:
940:     Either nout or idxout may be NULL. idx and idxout may be identical.

942:     For "small" problems when using ISGlobalToLocalMappingApply() and ISGlobalToLocalMappingApplyBlock(), the ISLocalToGlobalMappingType of ISLOCALTOGLOBALMAPPINGBASIC will be used;
943:     this uses more memory but is faster; this approach is not scalable for extremely large mappings. For large problems ISLOCALTOGLOBALMAPPINGHASH is used, this is scalable.
944:     Use ISLocalToGlobalMappingSetType() or call ISLocalToGlobalMappingSetFromOptions() with the option -islocaltoglobalmapping_type <basic,hash> to control which is used.

946:     Level: advanced

948:     Developer Note: The manual page states that idx and idxout may be identical but the calling
949:        sequence declares idx as const so it cannot be the same as idxout.

951: .seealso: ISLocalToGlobalMappingApply(), ISGlobalToLocalMappingApply(), ISLocalToGlobalMappingCreate(),
952:           ISLocalToGlobalMappingDestroy()
953: @*/
954: PetscErrorCode  ISGlobalToLocalMappingApplyBlock(ISLocalToGlobalMapping mapping,ISGlobalToLocalMappingMode type,
955:                                                  PetscInt n,const PetscInt idx[],PetscInt *nout,PetscInt idxout[])
956: {
958:   if (!mapping->data) {
959:     ISGlobalToLocalMappingSetUp(mapping);
960:   }
961:   (*mapping->ops->globaltolocalmappingapplyblock)(mapping,type,n,idx,nout,idxout);
962:   return 0;
963: }

965: /*@C
966:     ISLocalToGlobalMappingGetBlockInfo - Gets the neighbor information for each processor and
967:      each index shared by more than one processor

969:     Collective on ISLocalToGlobalMapping

971:     Input Parameter:
972: .   mapping - the mapping from local to global indexing

974:     Output Parameters:
975: +   nproc - number of processors that are connected to this one
976: .   proc - neighboring processors
977: .   numproc - number of indices for each subdomain (processor)
978: -   indices - indices of nodes (in local numbering) shared with neighbors (sorted by global numbering)

980:     Level: advanced

982:     Fortran Usage:
983: $        ISLocalToGlobalMpngGetInfoSize(ISLocalToGlobalMapping,PetscInt nproc,PetscInt numprocmax,ierr) followed by
984: $        ISLocalToGlobalMappingGetInfo(ISLocalToGlobalMapping,PetscInt nproc, PetscInt procs[nproc],PetscInt numprocs[nproc],
985:           PetscInt indices[nproc][numprocmax],ierr)
986:         There is no ISLocalToGlobalMappingRestoreInfo() in Fortran. You must make sure that procs[], numprocs[] and
987:         indices[][] are large enough arrays, either by allocating them dynamically or defining static ones large enough.

989: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreateIS(), ISLocalToGlobalMappingCreate(),
990:           ISLocalToGlobalMappingRestoreInfo()
991: @*/
992: PetscErrorCode  ISLocalToGlobalMappingGetBlockInfo(ISLocalToGlobalMapping mapping,PetscInt *nproc,PetscInt *procs[],PetscInt *numprocs[],PetscInt **indices[])
993: {
995:   if (mapping->info_cached) {
996:     *nproc    = mapping->info_nproc;
997:     *procs    = mapping->info_procs;
998:     *numprocs = mapping->info_numprocs;
999:     *indices  = mapping->info_indices;
1000:   } else {
1001:     ISLocalToGlobalMappingGetBlockInfo_Private(mapping,nproc,procs,numprocs,indices);
1002:   }
1003:   return 0;
1004: }

1006: static PetscErrorCode  ISLocalToGlobalMappingGetBlockInfo_Private(ISLocalToGlobalMapping mapping,PetscInt *nproc,PetscInt *procs[],PetscInt *numprocs[],PetscInt **indices[])
1007: {
1008:   PetscMPIInt    size,rank,tag1,tag2,tag3,*len,*source,imdex;
1009:   PetscInt       i,n = mapping->n,Ng,ng,max = 0,*lindices = mapping->indices;
1010:   PetscInt       *nprocs,*owner,nsends,*sends,j,*starts,nmax,nrecvs,*recvs,proc;
1011:   PetscInt       cnt,scale,*ownedsenders,*nownedsenders,rstart,nowned;
1012:   PetscInt       node,nownedm,nt,*sends2,nsends2,*starts2,*lens2,*dest,nrecvs2,*starts3,*recvs2,k,*bprocs,*tmp;
1013:   PetscInt       first_procs,first_numprocs,*first_indices;
1014:   MPI_Request    *recv_waits,*send_waits;
1015:   MPI_Status     recv_status,*send_status,*recv_statuses;
1016:   MPI_Comm       comm;
1017:   PetscBool      debug = PETSC_FALSE;

1019:   PetscObjectGetComm((PetscObject)mapping,&comm);
1020:   MPI_Comm_size(comm,&size);
1021:   MPI_Comm_rank(comm,&rank);
1022:   if (size == 1) {
1023:     *nproc         = 0;
1024:     *procs         = NULL;
1025:     PetscNew(numprocs);
1026:     (*numprocs)[0] = 0;
1027:     PetscNew(indices);
1028:     (*indices)[0]  = NULL;
1029:     /* save info for reuse */
1030:     mapping->info_nproc = *nproc;
1031:     mapping->info_procs = *procs;
1032:     mapping->info_numprocs = *numprocs;
1033:     mapping->info_indices = *indices;
1034:     mapping->info_cached = PETSC_TRUE;
1035:     return 0;
1036:   }

1038:   PetscOptionsGetBool(((PetscObject)mapping)->options,NULL,"-islocaltoglobalmappinggetinfo_debug",&debug,NULL);

1040:   /*
1041:     Notes on ISLocalToGlobalMappingGetBlockInfo

1043:     globally owned node - the nodes that have been assigned to this processor in global
1044:            numbering, just for this routine.

1046:     nontrivial globally owned node - node assigned to this processor that is on a subdomain
1047:            boundary (i.e. is has more than one local owner)

1049:     locally owned node - node that exists on this processors subdomain

1051:     nontrivial locally owned node - node that is not in the interior (i.e. has more than one
1052:            local subdomain
1053:   */
1054:   PetscObjectGetNewTag((PetscObject)mapping,&tag1);
1055:   PetscObjectGetNewTag((PetscObject)mapping,&tag2);
1056:   PetscObjectGetNewTag((PetscObject)mapping,&tag3);

1058:   for (i=0; i<n; i++) {
1059:     if (lindices[i] > max) max = lindices[i];
1060:   }
1061:   MPIU_Allreduce(&max,&Ng,1,MPIU_INT,MPI_MAX,comm);
1062:   Ng++;
1063:   MPI_Comm_size(comm,&size);
1064:   MPI_Comm_rank(comm,&rank);
1065:   scale  = Ng/size + 1;
1066:   ng     = scale; if (rank == size-1) ng = Ng - scale*(size-1); ng = PetscMax(1,ng);
1067:   rstart = scale*rank;

1069:   /* determine ownership ranges of global indices */
1070:   PetscMalloc1(2*size,&nprocs);
1071:   PetscArrayzero(nprocs,2*size);

1073:   /* determine owners of each local node  */
1074:   PetscMalloc1(n,&owner);
1075:   for (i=0; i<n; i++) {
1076:     proc             = lindices[i]/scale; /* processor that globally owns this index */
1077:     nprocs[2*proc+1] = 1;                 /* processor globally owns at least one of ours */
1078:     owner[i]         = proc;
1079:     nprocs[2*proc]++;                     /* count of how many that processor globally owns of ours */
1080:   }
1081:   nsends = 0; for (i=0; i<size; i++) nsends += nprocs[2*i+1];
1082:   PetscInfo(mapping,"Number of global owners for my local data %" PetscInt_FMT "\n",nsends);

1084:   /* inform other processors of number of messages and max length*/
1085:   PetscMaxSum(comm,nprocs,&nmax,&nrecvs);
1086:   PetscInfo(mapping,"Number of local owners for my global data %" PetscInt_FMT "\n",nrecvs);

1088:   /* post receives for owned rows */
1089:   PetscMalloc1((2*nrecvs+1)*(nmax+1),&recvs);
1090:   PetscMalloc1(nrecvs+1,&recv_waits);
1091:   for (i=0; i<nrecvs; i++) {
1092:     MPI_Irecv(recvs+2*nmax*i,2*nmax,MPIU_INT,MPI_ANY_SOURCE,tag1,comm,recv_waits+i);
1093:   }

1095:   /* pack messages containing lists of local nodes to owners */
1096:   PetscMalloc1(2*n+1,&sends);
1097:   PetscMalloc1(size+1,&starts);
1098:   starts[0] = 0;
1099:   for (i=1; i<size; i++) starts[i] = starts[i-1] + 2*nprocs[2*i-2];
1100:   for (i=0; i<n; i++) {
1101:     sends[starts[owner[i]]++] = lindices[i];
1102:     sends[starts[owner[i]]++] = i;
1103:   }
1104:   PetscFree(owner);
1105:   starts[0] = 0;
1106:   for (i=1; i<size; i++) starts[i] = starts[i-1] + 2*nprocs[2*i-2];

1108:   /* send the messages */
1109:   PetscMalloc1(nsends+1,&send_waits);
1110:   PetscMalloc1(nsends+1,&dest);
1111:   cnt = 0;
1112:   for (i=0; i<size; i++) {
1113:     if (nprocs[2*i]) {
1114:       MPI_Isend(sends+starts[i],2*nprocs[2*i],MPIU_INT,i,tag1,comm,send_waits+cnt);
1115:       dest[cnt] = i;
1116:       cnt++;
1117:     }
1118:   }
1119:   PetscFree(starts);

1121:   /* wait on receives */
1122:   PetscMalloc1(nrecvs+1,&source);
1123:   PetscMalloc1(nrecvs+1,&len);
1124:   cnt  = nrecvs;
1125:   PetscCalloc1(ng+1,&nownedsenders);
1126:   while (cnt) {
1127:     MPI_Waitany(nrecvs,recv_waits,&imdex,&recv_status);
1128:     /* unpack receives into our local space */
1129:     MPI_Get_count(&recv_status,MPIU_INT,&len[imdex]);
1130:     source[imdex] = recv_status.MPI_SOURCE;
1131:     len[imdex]    = len[imdex]/2;
1132:     /* count how many local owners for each of my global owned indices */
1133:     for (i=0; i<len[imdex]; i++) nownedsenders[recvs[2*imdex*nmax+2*i]-rstart]++;
1134:     cnt--;
1135:   }
1136:   PetscFree(recv_waits);

1138:   /* count how many globally owned indices are on an edge multiplied by how many processors own them. */
1139:   nowned  = 0;
1140:   nownedm = 0;
1141:   for (i=0; i<ng; i++) {
1142:     if (nownedsenders[i] > 1) {nownedm += nownedsenders[i]; nowned++;}
1143:   }

1145:   /* create single array to contain rank of all local owners of each globally owned index */
1146:   PetscMalloc1(nownedm+1,&ownedsenders);
1147:   PetscMalloc1(ng+1,&starts);
1148:   starts[0] = 0;
1149:   for (i=1; i<ng; i++) {
1150:     if (nownedsenders[i-1] > 1) starts[i] = starts[i-1] + nownedsenders[i-1];
1151:     else starts[i] = starts[i-1];
1152:   }

1154:   /* for each nontrivial globally owned node list all arriving processors */
1155:   for (i=0; i<nrecvs; i++) {
1156:     for (j=0; j<len[i]; j++) {
1157:       node = recvs[2*i*nmax+2*j]-rstart;
1158:       if (nownedsenders[node] > 1) ownedsenders[starts[node]++] = source[i];
1159:     }
1160:   }

1162:   if (debug) { /* -----------------------------------  */
1163:     starts[0] = 0;
1164:     for (i=1; i<ng; i++) {
1165:       if (nownedsenders[i-1] > 1) starts[i] = starts[i-1] + nownedsenders[i-1];
1166:       else starts[i] = starts[i-1];
1167:     }
1168:     for (i=0; i<ng; i++) {
1169:       if (nownedsenders[i] > 1) {
1170:         PetscSynchronizedPrintf(comm,"[%d] global node %" PetscInt_FMT " local owner processors: ",rank,i+rstart);
1171:         for (j=0; j<nownedsenders[i]; j++) {
1172:           PetscSynchronizedPrintf(comm,"%" PetscInt_FMT " ",ownedsenders[starts[i]+j]);
1173:         }
1174:         PetscSynchronizedPrintf(comm,"\n");
1175:       }
1176:     }
1177:     PetscSynchronizedFlush(comm,PETSC_STDOUT);
1178:   } /* -----------------------------------  */

1180:   /* wait on original sends */
1181:   if (nsends) {
1182:     PetscMalloc1(nsends,&send_status);
1183:     MPI_Waitall(nsends,send_waits,send_status);
1184:     PetscFree(send_status);
1185:   }
1186:   PetscFree(send_waits);
1187:   PetscFree(sends);
1188:   PetscFree(nprocs);

1190:   /* pack messages to send back to local owners */
1191:   starts[0] = 0;
1192:   for (i=1; i<ng; i++) {
1193:     if (nownedsenders[i-1] > 1) starts[i] = starts[i-1] + nownedsenders[i-1];
1194:     else starts[i] = starts[i-1];
1195:   }
1196:   nsends2 = nrecvs;
1197:   PetscMalloc1(nsends2+1,&nprocs); /* length of each message */
1198:   for (i=0; i<nrecvs; i++) {
1199:     nprocs[i] = 1;
1200:     for (j=0; j<len[i]; j++) {
1201:       node = recvs[2*i*nmax+2*j]-rstart;
1202:       if (nownedsenders[node] > 1) nprocs[i] += 2 + nownedsenders[node];
1203:     }
1204:   }
1205:   nt = 0;
1206:   for (i=0; i<nsends2; i++) nt += nprocs[i];

1208:   PetscMalloc1(nt+1,&sends2);
1209:   PetscMalloc1(nsends2+1,&starts2);

1211:   starts2[0] = 0;
1212:   for (i=1; i<nsends2; i++) starts2[i] = starts2[i-1] + nprocs[i-1];
1213:   /*
1214:      Each message is 1 + nprocs[i] long, and consists of
1215:        (0) the number of nodes being sent back
1216:        (1) the local node number,
1217:        (2) the number of processors sharing it,
1218:        (3) the processors sharing it
1219:   */
1220:   for (i=0; i<nsends2; i++) {
1221:     cnt = 1;
1222:     sends2[starts2[i]] = 0;
1223:     for (j=0; j<len[i]; j++) {
1224:       node = recvs[2*i*nmax+2*j]-rstart;
1225:       if (nownedsenders[node] > 1) {
1226:         sends2[starts2[i]]++;
1227:         sends2[starts2[i]+cnt++] = recvs[2*i*nmax+2*j+1];
1228:         sends2[starts2[i]+cnt++] = nownedsenders[node];
1229:         PetscArraycpy(&sends2[starts2[i]+cnt],&ownedsenders[starts[node]],nownedsenders[node]);
1230:         cnt += nownedsenders[node];
1231:       }
1232:     }
1233:   }

1235:   /* receive the message lengths */
1236:   nrecvs2 = nsends;
1237:   PetscMalloc1(nrecvs2+1,&lens2);
1238:   PetscMalloc1(nrecvs2+1,&starts3);
1239:   PetscMalloc1(nrecvs2+1,&recv_waits);
1240:   for (i=0; i<nrecvs2; i++) {
1241:     MPI_Irecv(&lens2[i],1,MPIU_INT,dest[i],tag2,comm,recv_waits+i);
1242:   }

1244:   /* send the message lengths */
1245:   for (i=0; i<nsends2; i++) {
1246:     MPI_Send(&nprocs[i],1,MPIU_INT,source[i],tag2,comm);
1247:   }

1249:   /* wait on receives of lens */
1250:   if (nrecvs2) {
1251:     PetscMalloc1(nrecvs2,&recv_statuses);
1252:     MPI_Waitall(nrecvs2,recv_waits,recv_statuses);
1253:     PetscFree(recv_statuses);
1254:   }
1255:   PetscFree(recv_waits);

1257:   starts3[0] = 0;
1258:   nt         = 0;
1259:   for (i=0; i<nrecvs2-1; i++) {
1260:     starts3[i+1] = starts3[i] + lens2[i];
1261:     nt          += lens2[i];
1262:   }
1263:   if (nrecvs2) nt += lens2[nrecvs2-1];

1265:   PetscMalloc1(nt+1,&recvs2);
1266:   PetscMalloc1(nrecvs2+1,&recv_waits);
1267:   for (i=0; i<nrecvs2; i++) {
1268:     MPI_Irecv(recvs2+starts3[i],lens2[i],MPIU_INT,dest[i],tag3,comm,recv_waits+i);
1269:   }

1271:   /* send the messages */
1272:   PetscMalloc1(nsends2+1,&send_waits);
1273:   for (i=0; i<nsends2; i++) {
1274:     MPI_Isend(sends2+starts2[i],nprocs[i],MPIU_INT,source[i],tag3,comm,send_waits+i);
1275:   }

1277:   /* wait on receives */
1278:   if (nrecvs2) {
1279:     PetscMalloc1(nrecvs2,&recv_statuses);
1280:     MPI_Waitall(nrecvs2,recv_waits,recv_statuses);
1281:     PetscFree(recv_statuses);
1282:   }
1283:   PetscFree(recv_waits);
1284:   PetscFree(nprocs);

1286:   if (debug) { /* -----------------------------------  */
1287:     cnt = 0;
1288:     for (i=0; i<nrecvs2; i++) {
1289:       nt = recvs2[cnt++];
1290:       for (j=0; j<nt; j++) {
1291:         PetscSynchronizedPrintf(comm,"[%d] local node %" PetscInt_FMT " number of subdomains %" PetscInt_FMT ": ",rank,recvs2[cnt],recvs2[cnt+1]);
1292:         for (k=0; k<recvs2[cnt+1]; k++) {
1293:           PetscSynchronizedPrintf(comm,"%" PetscInt_FMT " ",recvs2[cnt+2+k]);
1294:         }
1295:         cnt += 2 + recvs2[cnt+1];
1296:         PetscSynchronizedPrintf(comm,"\n");
1297:       }
1298:     }
1299:     PetscSynchronizedFlush(comm,PETSC_STDOUT);
1300:   } /* -----------------------------------  */

1302:   /* count number subdomains for each local node */
1303:   PetscCalloc1(size,&nprocs);
1304:   cnt  = 0;
1305:   for (i=0; i<nrecvs2; i++) {
1306:     nt = recvs2[cnt++];
1307:     for (j=0; j<nt; j++) {
1308:       for (k=0; k<recvs2[cnt+1]; k++) nprocs[recvs2[cnt+2+k]]++;
1309:       cnt += 2 + recvs2[cnt+1];
1310:     }
1311:   }
1312:   nt = 0; for (i=0; i<size; i++) nt += (nprocs[i] > 0);
1313:   *nproc    = nt;
1314:   PetscMalloc1(nt+1,procs);
1315:   PetscMalloc1(nt+1,numprocs);
1316:   PetscMalloc1(nt+1,indices);
1317:   for (i=0;i<nt+1;i++) (*indices)[i]=NULL;
1318:   PetscMalloc1(size,&bprocs);
1319:   cnt  = 0;
1320:   for (i=0; i<size; i++) {
1321:     if (nprocs[i] > 0) {
1322:       bprocs[i]        = cnt;
1323:       (*procs)[cnt]    = i;
1324:       (*numprocs)[cnt] = nprocs[i];
1325:       PetscMalloc1(nprocs[i],&(*indices)[cnt]);
1326:       cnt++;
1327:     }
1328:   }

1330:   /* make the list of subdomains for each nontrivial local node */
1331:   PetscArrayzero(*numprocs,nt);
1332:   cnt  = 0;
1333:   for (i=0; i<nrecvs2; i++) {
1334:     nt = recvs2[cnt++];
1335:     for (j=0; j<nt; j++) {
1336:       for (k=0; k<recvs2[cnt+1]; k++) (*indices)[bprocs[recvs2[cnt+2+k]]][(*numprocs)[bprocs[recvs2[cnt+2+k]]]++] = recvs2[cnt];
1337:       cnt += 2 + recvs2[cnt+1];
1338:     }
1339:   }
1340:   PetscFree(bprocs);
1341:   PetscFree(recvs2);

1343:   /* sort the node indexing by their global numbers */
1344:   nt = *nproc;
1345:   for (i=0; i<nt; i++) {
1346:     PetscMalloc1((*numprocs)[i],&tmp);
1347:     for (j=0; j<(*numprocs)[i]; j++) tmp[j] = lindices[(*indices)[i][j]];
1348:     PetscSortIntWithArray((*numprocs)[i],tmp,(*indices)[i]);
1349:     PetscFree(tmp);
1350:   }

1352:   if (debug) { /* -----------------------------------  */
1353:     nt = *nproc;
1354:     for (i=0; i<nt; i++) {
1355:       PetscSynchronizedPrintf(comm,"[%d] subdomain %" PetscInt_FMT " number of indices %" PetscInt_FMT ": ",rank,(*procs)[i],(*numprocs)[i]);
1356:       for (j=0; j<(*numprocs)[i]; j++) {
1357:         PetscSynchronizedPrintf(comm,"%" PetscInt_FMT " ",(*indices)[i][j]);
1358:       }
1359:       PetscSynchronizedPrintf(comm,"\n");
1360:     }
1361:     PetscSynchronizedFlush(comm,PETSC_STDOUT);
1362:   } /* -----------------------------------  */

1364:   /* wait on sends */
1365:   if (nsends2) {
1366:     PetscMalloc1(nsends2,&send_status);
1367:     MPI_Waitall(nsends2,send_waits,send_status);
1368:     PetscFree(send_status);
1369:   }

1371:   PetscFree(starts3);
1372:   PetscFree(dest);
1373:   PetscFree(send_waits);

1375:   PetscFree(nownedsenders);
1376:   PetscFree(ownedsenders);
1377:   PetscFree(starts);
1378:   PetscFree(starts2);
1379:   PetscFree(lens2);

1381:   PetscFree(source);
1382:   PetscFree(len);
1383:   PetscFree(recvs);
1384:   PetscFree(nprocs);
1385:   PetscFree(sends2);

1387:   /* put the information about myself as the first entry in the list */
1388:   first_procs    = (*procs)[0];
1389:   first_numprocs = (*numprocs)[0];
1390:   first_indices  = (*indices)[0];
1391:   for (i=0; i<*nproc; i++) {
1392:     if ((*procs)[i] == rank) {
1393:       (*procs)[0]    = (*procs)[i];
1394:       (*numprocs)[0] = (*numprocs)[i];
1395:       (*indices)[0]  = (*indices)[i];
1396:       (*procs)[i]    = first_procs;
1397:       (*numprocs)[i] = first_numprocs;
1398:       (*indices)[i]  = first_indices;
1399:       break;
1400:     }
1401:   }

1403:   /* save info for reuse */
1404:   mapping->info_nproc = *nproc;
1405:   mapping->info_procs = *procs;
1406:   mapping->info_numprocs = *numprocs;
1407:   mapping->info_indices = *indices;
1408:   mapping->info_cached = PETSC_TRUE;
1409:   return 0;
1410: }

1412: /*@C
1413:     ISLocalToGlobalMappingRestoreBlockInfo - Frees the memory allocated by ISLocalToGlobalMappingGetBlockInfo()

1415:     Collective on ISLocalToGlobalMapping

1417:     Input Parameter:
1418: .   mapping - the mapping from local to global indexing

1420:     Output Parameters:
1421: +   nproc - number of processors that are connected to this one
1422: .   proc - neighboring processors
1423: .   numproc - number of indices for each processor
1424: -   indices - indices of local nodes shared with neighbor (sorted by global numbering)

1426:     Level: advanced

1428: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreateIS(), ISLocalToGlobalMappingCreate(),
1429:           ISLocalToGlobalMappingGetInfo()
1430: @*/
1431: PetscErrorCode  ISLocalToGlobalMappingRestoreBlockInfo(ISLocalToGlobalMapping mapping,PetscInt *nproc,PetscInt *procs[],PetscInt *numprocs[],PetscInt **indices[])
1432: {
1434:   if (mapping->info_free) {
1435:     PetscFree(*numprocs);
1436:     if (*indices) {
1437:       PetscInt i;

1439:       PetscFree((*indices)[0]);
1440:       for (i=1; i<*nproc; i++) {
1441:         PetscFree((*indices)[i]);
1442:       }
1443:       PetscFree(*indices);
1444:     }
1445:   }
1446:   *nproc    = 0;
1447:   *procs    = NULL;
1448:   *numprocs = NULL;
1449:   *indices  = NULL;
1450:   return 0;
1451: }

1453: /*@C
1454:     ISLocalToGlobalMappingGetInfo - Gets the neighbor information for each processor and
1455:      each index shared by more than one processor

1457:     Collective on ISLocalToGlobalMapping

1459:     Input Parameter:
1460: .   mapping - the mapping from local to global indexing

1462:     Output Parameters:
1463: +   nproc - number of processors that are connected to this one
1464: .   proc - neighboring processors
1465: .   numproc - number of indices for each subdomain (processor)
1466: -   indices - indices of nodes (in local numbering) shared with neighbors (sorted by global numbering)

1468:     Level: advanced

1470:     Notes: The user needs to call ISLocalToGlobalMappingRestoreInfo when the data is no longer needed.

1472:     Fortran Usage:
1473: $        ISLocalToGlobalMpngGetInfoSize(ISLocalToGlobalMapping,PetscInt nproc,PetscInt numprocmax,ierr) followed by
1474: $        ISLocalToGlobalMappingGetInfo(ISLocalToGlobalMapping,PetscInt nproc, PetscInt procs[nproc],PetscInt numprocs[nproc],
1475:           PetscInt indices[nproc][numprocmax],ierr)
1476:         There is no ISLocalToGlobalMappingRestoreInfo() in Fortran. You must make sure that procs[], numprocs[] and
1477:         indices[][] are large enough arrays, either by allocating them dynamically or defining static ones large enough.

1479: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreateIS(), ISLocalToGlobalMappingCreate(),
1480:           ISLocalToGlobalMappingRestoreInfo()
1481: @*/
1482: PetscErrorCode  ISLocalToGlobalMappingGetInfo(ISLocalToGlobalMapping mapping,PetscInt *nproc,PetscInt *procs[],PetscInt *numprocs[],PetscInt **indices[])
1483: {
1484:   PetscInt       **bindices = NULL,*bnumprocs = NULL,bs,i,j,k;

1487:   bs = mapping->bs;
1488:   ISLocalToGlobalMappingGetBlockInfo(mapping,nproc,procs,&bnumprocs,&bindices);
1489:   if (bs > 1) { /* we need to expand the cached info */
1490:     PetscCalloc1(*nproc,&*indices);
1491:     PetscCalloc1(*nproc,&*numprocs);
1492:     for (i=0; i<*nproc; i++) {
1493:       PetscMalloc1(bs*bnumprocs[i],&(*indices)[i]);
1494:       for (j=0; j<bnumprocs[i]; j++) {
1495:         for (k=0; k<bs; k++) {
1496:           (*indices)[i][j*bs+k] = bs*bindices[i][j] + k;
1497:         }
1498:       }
1499:       (*numprocs)[i] = bnumprocs[i]*bs;
1500:     }
1501:     mapping->info_free = PETSC_TRUE;
1502:   } else {
1503:     *numprocs = bnumprocs;
1504:     *indices  = bindices;
1505:   }
1506:   return 0;
1507: }

1509: /*@C
1510:     ISLocalToGlobalMappingRestoreInfo - Frees the memory allocated by ISLocalToGlobalMappingGetInfo()

1512:     Collective on ISLocalToGlobalMapping

1514:     Input Parameter:
1515: .   mapping - the mapping from local to global indexing

1517:     Output Parameters:
1518: +   nproc - number of processors that are connected to this one
1519: .   proc - neighboring processors
1520: .   numproc - number of indices for each processor
1521: -   indices - indices of local nodes shared with neighbor (sorted by global numbering)

1523:     Level: advanced

1525: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreateIS(), ISLocalToGlobalMappingCreate(),
1526:           ISLocalToGlobalMappingGetInfo()
1527: @*/
1528: PetscErrorCode  ISLocalToGlobalMappingRestoreInfo(ISLocalToGlobalMapping mapping,PetscInt *nproc,PetscInt *procs[],PetscInt *numprocs[],PetscInt **indices[])
1529: {
1530:   ISLocalToGlobalMappingRestoreBlockInfo(mapping,nproc,procs,numprocs,indices);
1531:   return 0;
1532: }

1534: /*@C
1535:     ISLocalToGlobalMappingGetNodeInfo - Gets the neighbor information for each node

1537:     Collective on ISLocalToGlobalMapping

1539:     Input Parameter:
1540: .   mapping - the mapping from local to global indexing

1542:     Output Parameters:
1543: +   nnodes - number of local nodes (same ISLocalToGlobalMappingGetSize())
1544: .   count - number of neighboring processors per node
1545: -   indices - indices of processes sharing the node (sorted)

1547:     Level: advanced

1549:     Notes: The user needs to call ISLocalToGlobalMappingRestoreInfo when the data is no longer needed.

1551: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreateIS(), ISLocalToGlobalMappingCreate(),
1552:           ISLocalToGlobalMappingGetInfo(), ISLocalToGlobalMappingRestoreNodeInfo()
1553: @*/
1554: PetscErrorCode  ISLocalToGlobalMappingGetNodeInfo(ISLocalToGlobalMapping mapping,PetscInt *nnodes,PetscInt *count[],PetscInt **indices[])
1555: {
1556:   PetscInt       n;

1559:   ISLocalToGlobalMappingGetSize(mapping,&n);
1560:   if (!mapping->info_nodec) {
1561:     PetscInt i,m,n_neigh,*neigh,*n_shared,**shared;

1563:     PetscMalloc2(n+1,&mapping->info_nodec,n,&mapping->info_nodei);
1564:     ISLocalToGlobalMappingGetInfo(mapping,&n_neigh,&neigh,&n_shared,&shared);
1565:     for (i=0;i<n;i++) { mapping->info_nodec[i] = 1;}
1566:     m = n;
1567:     mapping->info_nodec[n] = 0;
1568:     for (i=1;i<n_neigh;i++) {
1569:       PetscInt j;

1571:       m += n_shared[i];
1572:       for (j=0;j<n_shared[i];j++) mapping->info_nodec[shared[i][j]] += 1;
1573:     }
1574:     if (n) PetscMalloc1(m,&mapping->info_nodei[0]);
1575:     for (i=1;i<n;i++) mapping->info_nodei[i] = mapping->info_nodei[i-1] + mapping->info_nodec[i-1];
1576:     PetscArrayzero(mapping->info_nodec,n);
1577:     for (i=0;i<n;i++) { mapping->info_nodec[i] = 1; mapping->info_nodei[i][0] = neigh[0]; }
1578:     for (i=1;i<n_neigh;i++) {
1579:       PetscInt j;

1581:       for (j=0;j<n_shared[i];j++) {
1582:         PetscInt k = shared[i][j];

1584:         mapping->info_nodei[k][mapping->info_nodec[k]] = neigh[i];
1585:         mapping->info_nodec[k] += 1;
1586:       }
1587:     }
1588:     for (i=0;i<n;i++) PetscSortRemoveDupsInt(&mapping->info_nodec[i],mapping->info_nodei[i]);
1589:     ISLocalToGlobalMappingRestoreInfo(mapping,&n_neigh,&neigh,&n_shared,&shared);
1590:   }
1591:   if (nnodes)  *nnodes  = n;
1592:   if (count)   *count   = mapping->info_nodec;
1593:   if (indices) *indices = mapping->info_nodei;
1594:   return 0;
1595: }

1597: /*@C
1598:     ISLocalToGlobalMappingRestoreNodeInfo - Frees the memory allocated by ISLocalToGlobalMappingGetNodeInfo()

1600:     Collective on ISLocalToGlobalMapping

1602:     Input Parameter:
1603: .   mapping - the mapping from local to global indexing

1605:     Output Parameters:
1606: +   nnodes - number of local nodes
1607: .   count - number of neighboring processors per node
1608: -   indices - indices of processes sharing the node (sorted)

1610:     Level: advanced

1612: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreateIS(), ISLocalToGlobalMappingCreate(),
1613:           ISLocalToGlobalMappingGetInfo()
1614: @*/
1615: PetscErrorCode  ISLocalToGlobalMappingRestoreNodeInfo(ISLocalToGlobalMapping mapping,PetscInt *nnodes,PetscInt *count[],PetscInt **indices[])
1616: {
1618:   if (nnodes)  *nnodes  = 0;
1619:   if (count)   *count   = NULL;
1620:   if (indices) *indices = NULL;
1621:   return 0;
1622: }

1624: /*@C
1625:    ISLocalToGlobalMappingGetIndices - Get global indices for every local point that is mapped

1627:    Not Collective

1629:    Input Parameter:
1630: . ltog - local to global mapping

1632:    Output Parameter:
1633: . array - array of indices, the length of this array may be obtained with ISLocalToGlobalMappingGetSize()

1635:    Level: advanced

1637:    Notes:
1638:     ISLocalToGlobalMappingGetSize() returns the length the this array

1640: .seealso: ISLocalToGlobalMappingCreate(), ISLocalToGlobalMappingApply(), ISLocalToGlobalMappingRestoreIndices(), ISLocalToGlobalMappingGetBlockIndices(), ISLocalToGlobalMappingRestoreBlockIndices()
1641: @*/
1642: PetscErrorCode  ISLocalToGlobalMappingGetIndices(ISLocalToGlobalMapping ltog,const PetscInt **array)
1643: {
1646:   if (ltog->bs == 1) {
1647:     *array = ltog->indices;
1648:   } else {
1649:     PetscInt       *jj,k,i,j,n = ltog->n, bs = ltog->bs;
1650:     const PetscInt *ii;

1652:     PetscMalloc1(bs*n,&jj);
1653:     *array = jj;
1654:     k    = 0;
1655:     ii   = ltog->indices;
1656:     for (i=0; i<n; i++)
1657:       for (j=0; j<bs; j++)
1658:         jj[k++] = bs*ii[i] + j;
1659:   }
1660:   return 0;
1661: }

1663: /*@C
1664:    ISLocalToGlobalMappingRestoreIndices - Restore indices obtained with ISLocalToGlobalMappingGetIndices()

1666:    Not Collective

1668:    Input Parameters:
1669: + ltog - local to global mapping
1670: - array - array of indices

1672:    Level: advanced

1674: .seealso: ISLocalToGlobalMappingCreate(), ISLocalToGlobalMappingApply(), ISLocalToGlobalMappingGetIndices()
1675: @*/
1676: PetscErrorCode  ISLocalToGlobalMappingRestoreIndices(ISLocalToGlobalMapping ltog,const PetscInt **array)
1677: {

1682:   if (ltog->bs > 1) {
1683:     PetscFree(*(void**)array);
1684:   }
1685:   return 0;
1686: }

1688: /*@C
1689:    ISLocalToGlobalMappingGetBlockIndices - Get global indices for every local block

1691:    Not Collective

1693:    Input Parameter:
1694: . ltog - local to global mapping

1696:    Output Parameter:
1697: . array - array of indices

1699:    Level: advanced

1701: .seealso: ISLocalToGlobalMappingCreate(), ISLocalToGlobalMappingApply(), ISLocalToGlobalMappingRestoreBlockIndices()
1702: @*/
1703: PetscErrorCode  ISLocalToGlobalMappingGetBlockIndices(ISLocalToGlobalMapping ltog,const PetscInt **array)
1704: {
1707:   *array = ltog->indices;
1708:   return 0;
1709: }

1711: /*@C
1712:    ISLocalToGlobalMappingRestoreBlockIndices - Restore indices obtained with ISLocalToGlobalMappingGetBlockIndices()

1714:    Not Collective

1716:    Input Parameters:
1717: + ltog - local to global mapping
1718: - array - array of indices

1720:    Level: advanced

1722: .seealso: ISLocalToGlobalMappingCreate(), ISLocalToGlobalMappingApply(), ISLocalToGlobalMappingGetIndices()
1723: @*/
1724: PetscErrorCode  ISLocalToGlobalMappingRestoreBlockIndices(ISLocalToGlobalMapping ltog,const PetscInt **array)
1725: {
1729:   *array = NULL;
1730:   return 0;
1731: }

1733: /*@C
1734:    ISLocalToGlobalMappingConcatenate - Create a new mapping that concatenates a list of mappings

1736:    Not Collective

1738:    Input Parameters:
1739: + comm - communicator for the new mapping, must contain the communicator of every mapping to concatenate
1740: . n - number of mappings to concatenate
1741: - ltogs - local to global mappings

1743:    Output Parameter:
1744: . ltogcat - new mapping

1746:    Note: this currently always returns a mapping with block size of 1

1748:    Developer Note: If all the input mapping have the same block size we could easily handle that as a special case

1750:    Level: advanced

1752: .seealso: ISLocalToGlobalMappingCreate()
1753: @*/
1754: PetscErrorCode ISLocalToGlobalMappingConcatenate(MPI_Comm comm,PetscInt n,const ISLocalToGlobalMapping ltogs[],ISLocalToGlobalMapping *ltogcat)
1755: {
1756:   PetscInt       i,cnt,m,*idx;

1762:   for (cnt=0,i=0; i<n; i++) {
1763:     ISLocalToGlobalMappingGetSize(ltogs[i],&m);
1764:     cnt += m;
1765:   }
1766:   PetscMalloc1(cnt,&idx);
1767:   for (cnt=0,i=0; i<n; i++) {
1768:     const PetscInt *subidx;
1769:     ISLocalToGlobalMappingGetSize(ltogs[i],&m);
1770:     ISLocalToGlobalMappingGetIndices(ltogs[i],&subidx);
1771:     PetscArraycpy(&idx[cnt],subidx,m);
1772:     ISLocalToGlobalMappingRestoreIndices(ltogs[i],&subidx);
1773:     cnt += m;
1774:   }
1775:   ISLocalToGlobalMappingCreate(comm,1,cnt,idx,PETSC_OWN_POINTER,ltogcat);
1776:   return 0;
1777: }

1779: /*MC
1780:       ISLOCALTOGLOBALMAPPINGBASIC - basic implementation of the ISLocalToGlobalMapping object. When ISGlobalToLocalMappingApply() is
1781:                                     used this is good for only small and moderate size problems.

1783:    Options Database Keys:
1784: .   -islocaltoglobalmapping_type basic - select this method

1786:    Level: beginner

1788: .seealso:  ISLocalToGlobalMappingCreate(), ISLocalToGlobalMappingSetType(), ISLOCALTOGLOBALMAPPINGHASH
1789: M*/
1790: PETSC_EXTERN PetscErrorCode ISLocalToGlobalMappingCreate_Basic(ISLocalToGlobalMapping ltog)
1791: {
1792:   ltog->ops->globaltolocalmappingapply      = ISGlobalToLocalMappingApply_Basic;
1793:   ltog->ops->globaltolocalmappingsetup      = ISGlobalToLocalMappingSetUp_Basic;
1794:   ltog->ops->globaltolocalmappingapplyblock = ISGlobalToLocalMappingApplyBlock_Basic;
1795:   ltog->ops->destroy                        = ISLocalToGlobalMappingDestroy_Basic;
1796:   return 0;
1797: }

1799: /*MC
1800:       ISLOCALTOGLOBALMAPPINGHASH - hash implementation of the ISLocalToGlobalMapping object. When ISGlobalToLocalMappingApply() is
1801:                                     used this is good for large memory problems.

1803:    Options Database Keys:
1804: .   -islocaltoglobalmapping_type hash - select this method

1806:    Notes:
1807:     This is selected automatically for large problems if the user does not set the type.

1809:    Level: beginner

1811: .seealso:  ISLocalToGlobalMappingCreate(), ISLocalToGlobalMappingSetType(), ISLOCALTOGLOBALMAPPINGHASH
1812: M*/
1813: PETSC_EXTERN PetscErrorCode ISLocalToGlobalMappingCreate_Hash(ISLocalToGlobalMapping ltog)
1814: {
1815:   ltog->ops->globaltolocalmappingapply      = ISGlobalToLocalMappingApply_Hash;
1816:   ltog->ops->globaltolocalmappingsetup      = ISGlobalToLocalMappingSetUp_Hash;
1817:   ltog->ops->globaltolocalmappingapplyblock = ISGlobalToLocalMappingApplyBlock_Hash;
1818:   ltog->ops->destroy                        = ISLocalToGlobalMappingDestroy_Hash;
1819:   return 0;
1820: }

1822: /*@C
1823:     ISLocalToGlobalMappingRegister -  Adds a method for applying a global to local mapping with an ISLocalToGlobalMapping

1825:    Not Collective

1827:    Input Parameters:
1828: +  sname - name of a new method
1829: -  routine_create - routine to create method context

1831:    Notes:
1832:    ISLocalToGlobalMappingRegister() may be called multiple times to add several user-defined mappings.

1834:    Sample usage:
1835: .vb
1836:    ISLocalToGlobalMappingRegister("my_mapper",MyCreate);
1837: .ve

1839:    Then, your mapping can be chosen with the procedural interface via
1840: $     ISLocalToGlobalMappingSetType(ltog,"my_mapper")
1841:    or at runtime via the option
1842: $     -islocaltoglobalmapping_type my_mapper

1844:    Level: advanced

1846: .seealso: ISLocalToGlobalMappingRegisterAll(), ISLocalToGlobalMappingRegisterDestroy(), ISLOCALTOGLOBALMAPPINGBASIC, ISLOCALTOGLOBALMAPPINGHASH

1848: @*/
1849: PetscErrorCode  ISLocalToGlobalMappingRegister(const char sname[],PetscErrorCode (*function)(ISLocalToGlobalMapping))
1850: {
1851:   ISInitializePackage();
1852:   PetscFunctionListAdd(&ISLocalToGlobalMappingList,sname,function);
1853:   return 0;
1854: }

1856: /*@C
1857:    ISLocalToGlobalMappingSetType - Builds ISLocalToGlobalMapping for a particular global to local mapping approach.

1859:    Logically Collective on ISLocalToGlobalMapping

1861:    Input Parameters:
1862: +  ltog - the ISLocalToGlobalMapping object
1863: -  type - a known method

1865:    Options Database Key:
1866: .  -islocaltoglobalmapping_type  <method> - Sets the method; use -help for a list
1867:     of available methods (for instance, basic or hash)

1869:    Notes:
1870:    See "petsc/include/petscis.h" for available methods

1872:   Normally, it is best to use the ISLocalToGlobalMappingSetFromOptions() command and
1873:   then set the ISLocalToGlobalMapping type from the options database rather than by using
1874:   this routine.

1876:   Level: intermediate

1878:   Developer Note: ISLocalToGlobalMappingRegister() is used to add new types to ISLocalToGlobalMappingList from which they
1879:   are accessed by ISLocalToGlobalMappingSetType().

1881: .seealso: ISLocalToGlobalMappingType, ISLocalToGlobalMappingRegister(), ISLocalToGlobalMappingCreate(), ISLocalToGlobalMappingGetType()
1882: @*/
1883: PetscErrorCode  ISLocalToGlobalMappingSetType(ISLocalToGlobalMapping ltog, ISLocalToGlobalMappingType type)
1884: {
1885:   PetscBool      match;
1886:   PetscErrorCode (*r)(ISLocalToGlobalMapping) = NULL;


1891:   PetscObjectTypeCompare((PetscObject)ltog,type,&match);
1892:   if (match) return 0;

1894:   /* L2G maps defer type setup at globaltolocal calls, allow passing NULL here */
1895:   if (type) {
1896:     PetscFunctionListFind(ISLocalToGlobalMappingList,type,&r);
1898:   }
1899:   /* Destroy the previous private LTOG context */
1900:   if (ltog->ops->destroy) {
1901:     (*ltog->ops->destroy)(ltog);
1902:     ltog->ops->destroy = NULL;
1903:   }
1904:   PetscObjectChangeTypeName((PetscObject)ltog,type);
1905:   if (r) (*r)(ltog);
1906:   return 0;
1907: }

1909: /*@C
1910:    ISLocalToGlobalMappingGetType - Get the type of the l2g map

1912:    Not Collective

1914:    Input Parameter:
1915: .  ltog - the ISLocalToGlobalMapping object

1917:    Output Parameter:
1918: .  type - the type

1920:    Level: intermediate

1922: .seealso: ISLocalToGlobalMappingType, ISLocalToGlobalMappingRegister(), ISLocalToGlobalMappingCreate(), ISLocalToGlobalMappingSetType()
1923: @*/
1924: PetscErrorCode  ISLocalToGlobalMappingGetType(ISLocalToGlobalMapping ltog, ISLocalToGlobalMappingType *type)
1925: {
1928:   *type = ((PetscObject)ltog)->type_name;
1929:   return 0;
1930: }

1932: PetscBool ISLocalToGlobalMappingRegisterAllCalled = PETSC_FALSE;

1934: /*@C
1935:   ISLocalToGlobalMappingRegisterAll - Registers all of the local to global mapping components in the IS package.

1937:   Not Collective

1939:   Level: advanced

1941: .seealso:  ISRegister(),  ISLocalToGlobalRegister()
1942: @*/
1943: PetscErrorCode  ISLocalToGlobalMappingRegisterAll(void)
1944: {
1945:   if (ISLocalToGlobalMappingRegisterAllCalled) return 0;
1946:   ISLocalToGlobalMappingRegisterAllCalled = PETSC_TRUE;
1947:   ISLocalToGlobalMappingRegister(ISLOCALTOGLOBALMAPPINGBASIC, ISLocalToGlobalMappingCreate_Basic);
1948:   ISLocalToGlobalMappingRegister(ISLOCALTOGLOBALMAPPINGHASH, ISLocalToGlobalMappingCreate_Hash);
1949:   return 0;
1950: }