Actual source code: section.c

  1: /*
  2:    This file contains routines for basic section object implementation.
  3: */

  5: #include <petsc/private/sectionimpl.h>
  6: #include <petscsf.h>

  8: PetscClassId PETSC_SECTION_CLASSID;

 10: /*@
 11:   PetscSectionCreate - Allocates `PetscSection` and sets the map contents to the default.

 13:   Collective

 15:   Input Parameters:
 16: + comm - the MPI communicator
 17: - s    - pointer to the section

 19:   Level: beginner

 21:   Notes:
 22:   Typical calling sequence
 23: .vb
 24:        PetscSectionCreate(MPI_Comm,PetscSection *);!
 25:        PetscSectionSetNumFields(PetscSection, numFields);
 26:        PetscSectionSetChart(PetscSection,low,high);
 27:        PetscSectionSetDof(PetscSection,point,numdof);
 28:        PetscSectionSetUp(PetscSection);
 29:        PetscSectionGetOffset(PetscSection,point,PetscInt *);
 30:        PetscSectionDestroy(PetscSection);
 31: .ve

 33:   The `PetscSection` object and methods are intended to be used in the PETSc `Vec` and `Mat` implementations. The indices returned by the `PetscSection` are appropriate for the kind of `Vec` it is associated with. For example, if the vector being indexed is a local vector, we call the section a local section. If the section indexes a global vector, we call it a global section. For parallel vectors, like global vectors, we use negative indices to indicate dofs owned by other processes.

 35: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionDestroy()`, `PetscSectionCreateGlobalSection()`
 36: @*/
 37: PetscErrorCode PetscSectionCreate(MPI_Comm comm, PetscSection *s)
 38: {
 39:   PetscFunctionBegin;
 41:   PetscCall(ISInitializePackage());

 43:   PetscCall(PetscHeaderCreate(*s, PETSC_SECTION_CLASSID, "PetscSection", "Section", "IS", comm, PetscSectionDestroy, PetscSectionView));

 45:   (*s)->pStart              = -1;
 46:   (*s)->pEnd                = -1;
 47:   (*s)->perm                = NULL;
 48:   (*s)->pointMajor          = PETSC_TRUE;
 49:   (*s)->includesConstraints = PETSC_TRUE;
 50:   (*s)->atlasDof            = NULL;
 51:   (*s)->atlasOff            = NULL;
 52:   (*s)->bc                  = NULL;
 53:   (*s)->bcIndices           = NULL;
 54:   (*s)->setup               = PETSC_FALSE;
 55:   (*s)->numFields           = 0;
 56:   (*s)->fieldNames          = NULL;
 57:   (*s)->field               = NULL;
 58:   (*s)->useFieldOff         = PETSC_FALSE;
 59:   (*s)->compNames           = NULL;
 60:   (*s)->clObj               = NULL;
 61:   (*s)->clHash              = NULL;
 62:   (*s)->clSection           = NULL;
 63:   (*s)->clPoints            = NULL;
 64:   PetscCall(PetscSectionInvalidateMaxDof_Internal(*s));
 65:   PetscFunctionReturn(PETSC_SUCCESS);
 66: }

 68: /*@
 69:   PetscSectionCopy - Creates a shallow (if possible) copy of the `PetscSection`

 71:   Collective

 73:   Input Parameter:
 74: . section - the `PetscSection`

 76:   Output Parameter:
 77: . newSection - the copy

 79:   Level: intermediate

 81:   Developer Note:
 82:   What exactly does shallow mean in this context?

 84: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionCreate()`, `PetscSectionDestroy()`
 85: @*/
 86: PetscErrorCode PetscSectionCopy(PetscSection section, PetscSection newSection)
 87: {
 88:   PetscSectionSym sym;
 89:   IS              perm;
 90:   PetscInt        numFields, f, c, pStart, pEnd, p;

 92:   PetscFunctionBegin;
 95:   PetscCall(PetscSectionReset(newSection));
 96:   PetscCall(PetscSectionGetNumFields(section, &numFields));
 97:   if (numFields) PetscCall(PetscSectionSetNumFields(newSection, numFields));
 98:   for (f = 0; f < numFields; ++f) {
 99:     const char *fieldName = NULL, *compName = NULL;
100:     PetscInt    numComp = 0;

102:     PetscCall(PetscSectionGetFieldName(section, f, &fieldName));
103:     PetscCall(PetscSectionSetFieldName(newSection, f, fieldName));
104:     PetscCall(PetscSectionGetFieldComponents(section, f, &numComp));
105:     PetscCall(PetscSectionSetFieldComponents(newSection, f, numComp));
106:     for (c = 0; c < numComp; ++c) {
107:       PetscCall(PetscSectionGetComponentName(section, f, c, &compName));
108:       PetscCall(PetscSectionSetComponentName(newSection, f, c, compName));
109:     }
110:     PetscCall(PetscSectionGetFieldSym(section, f, &sym));
111:     PetscCall(PetscSectionSetFieldSym(newSection, f, sym));
112:   }
113:   PetscCall(PetscSectionGetChart(section, &pStart, &pEnd));
114:   PetscCall(PetscSectionSetChart(newSection, pStart, pEnd));
115:   PetscCall(PetscSectionGetPermutation(section, &perm));
116:   PetscCall(PetscSectionSetPermutation(newSection, perm));
117:   PetscCall(PetscSectionGetSym(section, &sym));
118:   PetscCall(PetscSectionSetSym(newSection, sym));
119:   for (p = pStart; p < pEnd; ++p) {
120:     PetscInt dof, cdof, fcdof = 0;

122:     PetscCall(PetscSectionGetDof(section, p, &dof));
123:     PetscCall(PetscSectionSetDof(newSection, p, dof));
124:     PetscCall(PetscSectionGetConstraintDof(section, p, &cdof));
125:     if (cdof) PetscCall(PetscSectionSetConstraintDof(newSection, p, cdof));
126:     for (f = 0; f < numFields; ++f) {
127:       PetscCall(PetscSectionGetFieldDof(section, p, f, &dof));
128:       PetscCall(PetscSectionSetFieldDof(newSection, p, f, dof));
129:       if (cdof) {
130:         PetscCall(PetscSectionGetFieldConstraintDof(section, p, f, &fcdof));
131:         if (fcdof) PetscCall(PetscSectionSetFieldConstraintDof(newSection, p, f, fcdof));
132:       }
133:     }
134:   }
135:   PetscCall(PetscSectionSetUp(newSection));
136:   for (p = pStart; p < pEnd; ++p) {
137:     PetscInt        off, cdof, fcdof = 0;
138:     const PetscInt *cInd;

140:     /* Must set offsets in case they do not agree with the prefix sums */
141:     PetscCall(PetscSectionGetOffset(section, p, &off));
142:     PetscCall(PetscSectionSetOffset(newSection, p, off));
143:     PetscCall(PetscSectionGetConstraintDof(section, p, &cdof));
144:     if (cdof) {
145:       PetscCall(PetscSectionGetConstraintIndices(section, p, &cInd));
146:       PetscCall(PetscSectionSetConstraintIndices(newSection, p, cInd));
147:       for (f = 0; f < numFields; ++f) {
148:         PetscCall(PetscSectionGetFieldConstraintDof(section, p, f, &fcdof));
149:         if (fcdof) {
150:           PetscCall(PetscSectionGetFieldConstraintIndices(section, p, f, &cInd));
151:           PetscCall(PetscSectionSetFieldConstraintIndices(newSection, p, f, cInd));
152:         }
153:       }
154:     }
155:   }
156:   PetscFunctionReturn(PETSC_SUCCESS);
157: }

159: /*@
160:   PetscSectionClone - Creates a shallow (if possible) copy of the `PetscSection`

162:   Collective

164:   Input Parameter:
165: . section - the `PetscSection`

167:   Output Parameter:
168: . newSection - the copy

170:   Level: beginner

172:   Developer Note:
173:   With standard PETSc terminology this should be called `PetscSectionDuplicate()`

175: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionCreate()`, `PetscSectionDestroy()`, `PetscSectionCopy()`
176: @*/
177: PetscErrorCode PetscSectionClone(PetscSection section, PetscSection *newSection)
178: {
179:   PetscFunctionBegin;
182:   PetscCall(PetscSectionCreate(PetscObjectComm((PetscObject)section), newSection));
183:   PetscCall(PetscSectionCopy(section, *newSection));
184:   PetscFunctionReturn(PETSC_SUCCESS);
185: }

187: /*@
188:   PetscSectionSetFromOptions - sets parameters in a `PetscSection` from the options database

190:   Collective

192:   Input Parameter:
193: . section - the `PetscSection`

195:   Options Database:
196: . -petscsection_point_major - `PETSC_TRUE` for point-major order

198:   Level: intermediate

200: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionCreate()`, `PetscSectionDestroy()`
201: @*/
202: PetscErrorCode PetscSectionSetFromOptions(PetscSection s)
203: {
204:   PetscFunctionBegin;
206:   PetscObjectOptionsBegin((PetscObject)s);
207:   PetscCall(PetscOptionsBool("-petscsection_point_major", "The for ordering, either point major or field major", "PetscSectionSetPointMajor", s->pointMajor, &s->pointMajor, NULL));
208:   /* process any options handlers added with PetscObjectAddOptionsHandler() */
209:   PetscCall(PetscObjectProcessOptionsHandlers((PetscObject)s, PetscOptionsObject));
210:   PetscOptionsEnd();
211:   PetscCall(PetscObjectViewFromOptions((PetscObject)s, NULL, "-petscsection_view"));
212:   PetscFunctionReturn(PETSC_SUCCESS);
213: }

215: /*@
216:   PetscSectionCompare - Compares two sections

218:   Collective

220:   Input Parameters:
221: + s1 - the first `PetscSection`
222: - s2 - the second `PetscSection`

224:   Output Parameter:
225: . congruent - `PETSC_TRUE` if the two sections are congruent, `PETSC_FALSE` otherwise

227:   Level: intermediate

229:   Note:
230:   Field names are disregarded.

232: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionCreate()`, `PetscSectionCopy()`, `PetscSectionClone()`
233: @*/
234: PetscErrorCode PetscSectionCompare(PetscSection s1, PetscSection s2, PetscBool *congruent)
235: {
236:   PetscInt        pStart, pEnd, nfields, ncdof, nfcdof, p, f, n1, n2;
237:   const PetscInt *idx1, *idx2;
238:   IS              perm1, perm2;
239:   PetscBool       flg;
240:   PetscMPIInt     mflg;

242:   PetscFunctionBegin;
246:   flg = PETSC_FALSE;

248:   PetscCallMPI(MPI_Comm_compare(PetscObjectComm((PetscObject)s1), PetscObjectComm((PetscObject)s2), &mflg));
249:   if (mflg != MPI_CONGRUENT && mflg != MPI_IDENT) {
250:     *congruent = PETSC_FALSE;
251:     PetscFunctionReturn(PETSC_SUCCESS);
252:   }

254:   PetscCall(PetscSectionGetChart(s1, &pStart, &pEnd));
255:   PetscCall(PetscSectionGetChart(s2, &n1, &n2));
256:   if (pStart != n1 || pEnd != n2) goto not_congruent;

258:   PetscCall(PetscSectionGetPermutation(s1, &perm1));
259:   PetscCall(PetscSectionGetPermutation(s2, &perm2));
260:   if (perm1 && perm2) {
261:     PetscCall(ISEqual(perm1, perm2, congruent));
262:     if (!(*congruent)) goto not_congruent;
263:   } else if (perm1 != perm2) goto not_congruent;

265:   for (p = pStart; p < pEnd; ++p) {
266:     PetscCall(PetscSectionGetOffset(s1, p, &n1));
267:     PetscCall(PetscSectionGetOffset(s2, p, &n2));
268:     if (n1 != n2) goto not_congruent;

270:     PetscCall(PetscSectionGetDof(s1, p, &n1));
271:     PetscCall(PetscSectionGetDof(s2, p, &n2));
272:     if (n1 != n2) goto not_congruent;

274:     PetscCall(PetscSectionGetConstraintDof(s1, p, &ncdof));
275:     PetscCall(PetscSectionGetConstraintDof(s2, p, &n2));
276:     if (ncdof != n2) goto not_congruent;

278:     PetscCall(PetscSectionGetConstraintIndices(s1, p, &idx1));
279:     PetscCall(PetscSectionGetConstraintIndices(s2, p, &idx2));
280:     PetscCall(PetscArraycmp(idx1, idx2, ncdof, congruent));
281:     if (!(*congruent)) goto not_congruent;
282:   }

284:   PetscCall(PetscSectionGetNumFields(s1, &nfields));
285:   PetscCall(PetscSectionGetNumFields(s2, &n2));
286:   if (nfields != n2) goto not_congruent;

288:   for (f = 0; f < nfields; ++f) {
289:     PetscCall(PetscSectionGetFieldComponents(s1, f, &n1));
290:     PetscCall(PetscSectionGetFieldComponents(s2, f, &n2));
291:     if (n1 != n2) goto not_congruent;

293:     for (p = pStart; p < pEnd; ++p) {
294:       PetscCall(PetscSectionGetFieldOffset(s1, p, f, &n1));
295:       PetscCall(PetscSectionGetFieldOffset(s2, p, f, &n2));
296:       if (n1 != n2) goto not_congruent;

298:       PetscCall(PetscSectionGetFieldDof(s1, p, f, &n1));
299:       PetscCall(PetscSectionGetFieldDof(s2, p, f, &n2));
300:       if (n1 != n2) goto not_congruent;

302:       PetscCall(PetscSectionGetFieldConstraintDof(s1, p, f, &nfcdof));
303:       PetscCall(PetscSectionGetFieldConstraintDof(s2, p, f, &n2));
304:       if (nfcdof != n2) goto not_congruent;

306:       PetscCall(PetscSectionGetFieldConstraintIndices(s1, p, f, &idx1));
307:       PetscCall(PetscSectionGetFieldConstraintIndices(s2, p, f, &idx2));
308:       PetscCall(PetscArraycmp(idx1, idx2, nfcdof, congruent));
309:       if (!(*congruent)) goto not_congruent;
310:     }
311:   }

313:   flg = PETSC_TRUE;
314: not_congruent:
315:   PetscCall(MPIU_Allreduce(&flg, congruent, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)s1)));
316:   PetscFunctionReturn(PETSC_SUCCESS);
317: }

319: /*@
320:   PetscSectionGetNumFields - Returns the number of fields in a `PetscSection`, or 0 if no fields were defined.

322:   Not Collective

324:   Input Parameter:
325: . s - the `PetscSection`

327:   Output Parameter:
328: . numFields - the number of fields defined, or 0 if none were defined

330:   Level: intermediate

332: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionSetNumFields()`
333: @*/
334: PetscErrorCode PetscSectionGetNumFields(PetscSection s, PetscInt *numFields)
335: {
336:   PetscFunctionBegin;
339:   *numFields = s->numFields;
340:   PetscFunctionReturn(PETSC_SUCCESS);
341: }

343: /*@
344:   PetscSectionSetNumFields - Sets the number of fields in a `PetscSection`

346:   Not Collective

348:   Input Parameters:
349: + s - the PetscSection
350: - numFields - the number of fields

352:   Level: intermediate

354: .seealso: [PetscSection](sec_petscsection), `PetscSection()`, `PetscSectionGetNumFields()`
355: @*/
356: PetscErrorCode PetscSectionSetNumFields(PetscSection s, PetscInt numFields)
357: {
358:   PetscInt f;

360:   PetscFunctionBegin;
362:   PetscCheck(numFields > 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "The number of fields %" PetscInt_FMT " must be positive", numFields);
363:   PetscCall(PetscSectionReset(s));

365:   s->numFields = numFields;
366:   PetscCall(PetscMalloc1(s->numFields, &s->numFieldComponents));
367:   PetscCall(PetscMalloc1(s->numFields, &s->fieldNames));
368:   PetscCall(PetscMalloc1(s->numFields, &s->compNames));
369:   PetscCall(PetscMalloc1(s->numFields, &s->field));
370:   for (f = 0; f < s->numFields; ++f) {
371:     char name[64];

373:     s->numFieldComponents[f] = 1;

375:     PetscCall(PetscSectionCreate(PetscObjectComm((PetscObject)s), &s->field[f]));
376:     PetscCall(PetscSNPrintf(name, 64, "Field_%" PetscInt_FMT, f));
377:     PetscCall(PetscStrallocpy(name, (char **)&s->fieldNames[f]));
378:     PetscCall(PetscSNPrintf(name, 64, "Component_0"));
379:     PetscCall(PetscMalloc1(s->numFieldComponents[f], &s->compNames[f]));
380:     PetscCall(PetscStrallocpy(name, (char **)&s->compNames[f][0]));
381:   }
382:   PetscFunctionReturn(PETSC_SUCCESS);
383: }

385: /*@C
386:   PetscSectionGetFieldName - Returns the name of a field in the `PetscSection`

388:   Not Collective

390:   Input Parameters:
391: + s     - the `PetscSection`
392: - field - the field number

394:   Output Parameter:
395: . fieldName - the field name

397:   Level: intermediate

399:   Note:
400:   Will error if the field number is out of range

402: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionSetFieldName()`, `PetscSectionSetNumFields()`, `PetscSectionGetNumFields()`
403: @*/
404: PetscErrorCode PetscSectionGetFieldName(PetscSection s, PetscInt field, const char *fieldName[])
405: {
406:   PetscFunctionBegin;
409:   PetscSectionCheckValidField(field, s->numFields);
410:   *fieldName = s->fieldNames[field];
411:   PetscFunctionReturn(PETSC_SUCCESS);
412: }

414: /*@C
415:   PetscSectionSetFieldName - Sets the name of a field in the `PetscSection`

417:   Not Collective

419:   Input Parameters:
420: + s     - the `PetscSection`
421: . field - the field number
422: - fieldName - the field name

424:   Level: intermediate

426:   Note:
427:   Will error if the field number is out of range

429: .seealso: [PetscSection](sec_petscsection), `PetscSectionGetFieldName()`, `PetscSectionSetNumFields()`, `PetscSectionGetNumFields()`
430: @*/
431: PetscErrorCode PetscSectionSetFieldName(PetscSection s, PetscInt field, const char fieldName[])
432: {
433:   PetscFunctionBegin;
436:   PetscSectionCheckValidField(field, s->numFields);
437:   PetscCall(PetscFree(s->fieldNames[field]));
438:   PetscCall(PetscStrallocpy(fieldName, (char **)&s->fieldNames[field]));
439:   PetscFunctionReturn(PETSC_SUCCESS);
440: }

442: /*@C
443:   PetscSectionGetComponentName - Gets the name of a field component in the `PetscSection`

445:   Not Collective

447:   Input Parameters:
448: + s     - the `PetscSection`
449: . field - the field number
450: - comp  - the component number

452:   Output Parameter:
453: . compName - the component name

455:   Level: intermediate

457:   Note:
458:   Will error if the field or component number do not exist

460: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetFieldName()`, `PetscSectionSetNumFields()`, `PetscSectionGetNumFields()`,
461:           `PetscSectionSetComponentName()`, `PetscSectionSetFieldName()`, `PetscSectionGetFieldComponents()`, `PetscSectionSetFieldComponents()`
462: @*/
463: PetscErrorCode PetscSectionGetComponentName(PetscSection s, PetscInt field, PetscInt comp, const char *compName[])
464: {
465:   PetscFunctionBegin;
468:   PetscSectionCheckValidField(field, s->numFields);
469:   PetscSectionCheckValidFieldComponent(comp, s->numFieldComponents[field]);
470:   *compName = s->compNames[field][comp];
471:   PetscFunctionReturn(PETSC_SUCCESS);
472: }

474: /*@C
475:   PetscSectionSetComponentName - Sets the name of a field component in the `PetscSection`

477:   Not Collective

479:   Input Parameters:
480: + s     - the PetscSection
481: . field - the field number
482: . comp  - the component number
483: - compName - the component name

485:   Level: intermediate

487:   Note:
488:   Will error if the field or component number do not exist

490: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetComponentName()`, `PetscSectionSetNumFields()`, `PetscSectionGetNumFields()`,
491:           `PetscSectionSetComponentName()`, `PetscSectionSetFieldName()`, `PetscSectionGetFieldComponents()`, `PetscSectionSetFieldComponents()`
492: @*/
493: PetscErrorCode PetscSectionSetComponentName(PetscSection s, PetscInt field, PetscInt comp, const char compName[])
494: {
495:   PetscFunctionBegin;
498:   PetscSectionCheckValidField(field, s->numFields);
499:   PetscSectionCheckValidFieldComponent(comp, s->numFieldComponents[field]);
500:   PetscCall(PetscFree(s->compNames[field][comp]));
501:   PetscCall(PetscStrallocpy(compName, (char **)&s->compNames[field][comp]));
502:   PetscFunctionReturn(PETSC_SUCCESS);
503: }

505: /*@
506:   PetscSectionGetFieldComponents - Returns the number of field components for the given field.

508:   Not Collective

510:   Input Parameters:
511: + s - the `PetscSection`
512: - field - the field number

514:   Output Parameter:
515: . numComp - the number of field components

517:   Level: intermediate

519:   Developer Note:
520:   This function is misnamed. There is a Num in `PetscSectionGetNumFields()` but not in this name

522: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionSetFieldComponents()`, `PetscSectionGetNumFields()`
523: @*/
524: PetscErrorCode PetscSectionGetFieldComponents(PetscSection s, PetscInt field, PetscInt *numComp)
525: {
526:   PetscFunctionBegin;
529:   PetscSectionCheckValidField(field, s->numFields);
530:   *numComp = s->numFieldComponents[field];
531:   PetscFunctionReturn(PETSC_SUCCESS);
532: }

534: /*@
535:   PetscSectionSetFieldComponents - Sets the number of field components for the given field.

537:   Not Collective

539:   Input Parameters:
540: + s - the PetscSection
541: . field - the field number
542: - numComp - the number of field components

544:   Level: intermediate

546: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetFieldComponents()`, `PetscSectionGetNumFields()`
547: @*/
548: PetscErrorCode PetscSectionSetFieldComponents(PetscSection s, PetscInt field, PetscInt numComp)
549: {
550:   PetscInt c;

552:   PetscFunctionBegin;
554:   PetscSectionCheckValidField(field, s->numFields);
555:   if (s->compNames) {
556:     for (c = 0; c < s->numFieldComponents[field]; ++c) PetscCall(PetscFree(s->compNames[field][c]));
557:     PetscCall(PetscFree(s->compNames[field]));
558:   }

560:   s->numFieldComponents[field] = numComp;
561:   if (numComp) {
562:     PetscCall(PetscMalloc1(numComp, (char ***)&s->compNames[field]));
563:     for (c = 0; c < numComp; ++c) {
564:       char name[64];

566:       PetscCall(PetscSNPrintf(name, 64, "%" PetscInt_FMT, c));
567:       PetscCall(PetscStrallocpy(name, (char **)&s->compNames[field][c]));
568:     }
569:   }
570:   PetscFunctionReturn(PETSC_SUCCESS);
571: }

573: /*@
574:   PetscSectionGetChart - Returns the range [pStart, pEnd) in which points (indices) lie for this `PetscSection`

576:   Not Collective

578:   Input Parameter:
579: . s - the `PetscSection`

581:   Output Parameters:
582: + pStart - the first point
583: - pEnd - one past the last point

585:   Level: intermediate

587: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionSetChart()`, `PetscSectionCreate()`
588: @*/
589: PetscErrorCode PetscSectionGetChart(PetscSection s, PetscInt *pStart, PetscInt *pEnd)
590: {
591:   PetscFunctionBegin;
593:   if (pStart) *pStart = s->pStart;
594:   if (pEnd) *pEnd = s->pEnd;
595:   PetscFunctionReturn(PETSC_SUCCESS);
596: }

598: /*@
599:   PetscSectionSetChart - Sets the range [pStart, pEnd) in which points (indices) lie for this `PetscSection`

601:   Not Collective

603:   Input Parameters:
604: + s - the PetscSection
605: . pStart - the first point
606: - pEnd - one past the last point

608:   Level: intermediate

610: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetChart()`, `PetscSectionCreate()`
611: @*/
612: PetscErrorCode PetscSectionSetChart(PetscSection s, PetscInt pStart, PetscInt pEnd)
613: {
614:   PetscInt f;

616:   PetscFunctionBegin;
618:   if (pStart == s->pStart && pEnd == s->pEnd) PetscFunctionReturn(PETSC_SUCCESS);
619:   /* Cannot Reset() because it destroys field information */
620:   s->setup = PETSC_FALSE;
621:   PetscCall(PetscSectionDestroy(&s->bc));
622:   PetscCall(PetscFree(s->bcIndices));
623:   PetscCall(PetscFree2(s->atlasDof, s->atlasOff));

625:   s->pStart = pStart;
626:   s->pEnd   = pEnd;
627:   PetscCall(PetscMalloc2((pEnd - pStart), &s->atlasDof, (pEnd - pStart), &s->atlasOff));
628:   PetscCall(PetscArrayzero(s->atlasDof, pEnd - pStart));
629:   for (f = 0; f < s->numFields; ++f) PetscCall(PetscSectionSetChart(s->field[f], pStart, pEnd));
630:   PetscFunctionReturn(PETSC_SUCCESS);
631: }

633: /*@
634:   PetscSectionGetPermutation - Returns the permutation of [0, pEnd-pStart) or NULL that was set with `PetscSectionSetPermutation()`

636:   Not Collective

638:   Input Parameter:
639: . s - the `PetscSection`

641:   Output Parameters:
642: . perm - The permutation as an `IS`

644:   Level: intermediate

646: .seealso: [](sec_scatter), `IS`, `PetscSection`, `PetscSectionSetPermutation()`, `PetscSectionCreate()`
647: @*/
648: PetscErrorCode PetscSectionGetPermutation(PetscSection s, IS *perm)
649: {
650:   PetscFunctionBegin;
652:   if (perm) {
654:     *perm = s->perm;
655:   }
656:   PetscFunctionReturn(PETSC_SUCCESS);
657: }

659: /*@
660:   PetscSectionSetPermutation - Sets the permutation for [0, pEnd-pStart)

662:   Not Collective

664:   Input Parameters:
665: + s - the PetscSection
666: - perm - the permutation of points

668:   Level: intermediate

670:   Developer Note:
671:   What purpose does this permutation serve?

673: .seealso: [](sec_scatter), `IS`, `PetscSection`, `PetscSectionGetPermutation()`, `PetscSectionCreate()`
674: @*/
675: PetscErrorCode PetscSectionSetPermutation(PetscSection s, IS perm)
676: {
677:   PetscFunctionBegin;
680:   PetscCheck(!s->setup, PetscObjectComm((PetscObject)s), PETSC_ERR_ARG_WRONGSTATE, "Cannot set a permutation after the section is setup");
681:   if (s->perm != perm) {
682:     PetscCall(ISDestroy(&s->perm));
683:     if (perm) {
684:       s->perm = perm;
685:       PetscCall(PetscObjectReference((PetscObject)s->perm));
686:     }
687:   }
688:   PetscFunctionReturn(PETSC_SUCCESS);
689: }

691: /*@
692:   PetscSectionGetPointMajor - Returns the flag for dof ordering, `PETSC_TRUE` if it is point major, `PETSC_FALSE` if it is field major

694:   Not Collective

696:   Input Parameter:
697: . s - the `PetscSection`

699:   Output Parameter:
700: . pm - the flag for point major ordering

702:   Level: intermediate

704: .seealso: [PetscSection](sec_petscsection), `PetscSection`, PetscSectionSetPointMajor()`
705: @*/
706: PetscErrorCode PetscSectionGetPointMajor(PetscSection s, PetscBool *pm)
707: {
708:   PetscFunctionBegin;
711:   *pm = s->pointMajor;
712:   PetscFunctionReturn(PETSC_SUCCESS);
713: }

715: /*@
716:   PetscSectionSetPointMajor - Sets the flag for dof ordering, `PETSC_TRUE` for point major, otherwise it will be field major

718:   Not Collective

720:   Input Parameters:
721: + s  - the `PetscSection`
722: - pm - the flag for point major ordering

724:   Level: intermediate

726: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetPointMajor()`
727: @*/
728: PetscErrorCode PetscSectionSetPointMajor(PetscSection s, PetscBool pm)
729: {
730:   PetscFunctionBegin;
732:   PetscCheck(!s->setup, PetscObjectComm((PetscObject)s), PETSC_ERR_ARG_WRONGSTATE, "Cannot set the dof ordering after the section is setup");
733:   s->pointMajor = pm;
734:   PetscFunctionReturn(PETSC_SUCCESS);
735: }

737: /*@
738:   PetscSectionGetIncludesConstraints - Returns the flag indicating if constrained dofs were included when computing offsets in the `PetscSection`.
739:   The value is set with `PetscSectionSetIncludesConstraints()`

741:   Not Collective

743:   Input Parameter:
744: . s - the `PetscSection`

746:   Output Parameter:
747: . includesConstraints - the flag indicating if constrained dofs were included when computing offsets

749:   Level: intermediate

751: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionSetIncludesConstraints()`
752: @*/
753: PetscErrorCode PetscSectionGetIncludesConstraints(PetscSection s, PetscBool *includesConstraints)
754: {
755:   PetscFunctionBegin;
758:   *includesConstraints = s->includesConstraints;
759:   PetscFunctionReturn(PETSC_SUCCESS);
760: }

762: /*@
763:   PetscSectionSetIncludesConstraints - Sets the flag indicating if constrained dofs are to be included when computing offsets

765:   Not Collective

767:   Input Parameters:
768: + s  - the PetscSection
769: - includesConstraints - the flag indicating if constrained dofs are to be included when computing offsets

771:   Level: intermediate

773: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetIncludesConstraints()`
774: @*/
775: PetscErrorCode PetscSectionSetIncludesConstraints(PetscSection s, PetscBool includesConstraints)
776: {
777:   PetscFunctionBegin;
779:   PetscCheck(!s->setup, PetscObjectComm((PetscObject)s), PETSC_ERR_ARG_WRONGSTATE, "Cannot set includesConstraints after the section is set up");
780:   s->includesConstraints = includesConstraints;
781:   PetscFunctionReturn(PETSC_SUCCESS);
782: }

784: /*@
785:   PetscSectionGetDof - Return the number of degrees of freedom associated with a given point.

787:   Not Collective

789:   Input Parameters:
790: + s - the `PetscSection`
791: - point - the point

793:   Output Parameter:
794: . numDof - the number of dof

796:   Note:
797:   In a global section, this size will be negative for points not owned by this process.

799:   Level: intermediate

801: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionSetDof()`, `PetscSectionCreate()`
802: @*/
803: PetscErrorCode PetscSectionGetDof(PetscSection s, PetscInt point, PetscInt *numDof)
804: {
805:   PetscFunctionBeginHot;
808:   PetscAssert(point >= s->pStart && point < s->pEnd, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Section point %" PetscInt_FMT " should be in [%" PetscInt_FMT ", %" PetscInt_FMT ")", point, s->pStart, s->pEnd);
809:   *numDof = s->atlasDof[point - s->pStart];
810:   PetscFunctionReturn(PETSC_SUCCESS);
811: }

813: /*@
814:   PetscSectionSetDof - Sets the number of degrees of freedom associated with a given point.

816:   Not Collective

818:   Input Parameters:
819: + s - the `PetscSection`
820: . point - the point
821: - numDof - the number of dof

823:   Level: intermediate

825: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetDof()`, `PetscSectionAddDof()`, `PetscSectionCreate()`
826: @*/
827: PetscErrorCode PetscSectionSetDof(PetscSection s, PetscInt point, PetscInt numDof)
828: {
829:   PetscFunctionBegin;
831:   PetscAssert(point >= s->pStart && point < s->pEnd, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Section point %" PetscInt_FMT " should be in [%" PetscInt_FMT ", %" PetscInt_FMT ")", point, s->pStart, s->pEnd);
832:   s->atlasDof[point - s->pStart] = numDof;
833:   PetscCall(PetscSectionInvalidateMaxDof_Internal(s));
834:   PetscFunctionReturn(PETSC_SUCCESS);
835: }

837: /*@
838:   PetscSectionAddDof - Adds to the number of degrees of freedom associated with a given point.

840:   Not Collective

842:   Input Parameters:
843: + s - the `PetscSection`
844: . point - the point
845: - numDof - the number of additional dof

847:   Level: intermediate

849: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetDof()`, `PetscSectionSetDof()`, `PetscSectionCreate()`
850: @*/
851: PetscErrorCode PetscSectionAddDof(PetscSection s, PetscInt point, PetscInt numDof)
852: {
853:   PetscFunctionBeginHot;
855:   PetscAssert(point >= s->pStart && point < s->pEnd, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Section point %" PetscInt_FMT " should be in [%" PetscInt_FMT ", %" PetscInt_FMT ")", point, s->pStart, s->pEnd);
856:   s->atlasDof[point - s->pStart] += numDof;
857:   PetscCall(PetscSectionInvalidateMaxDof_Internal(s));
858:   PetscFunctionReturn(PETSC_SUCCESS);
859: }

861: /*@
862:   PetscSectionGetFieldDof - Return the number of degrees of freedom associated with a field on a given point.

864:   Not Collective

866:   Input Parameters:
867: + s - the `PetscSection`
868: . point - the point
869: - field - the field

871:   Output Parameter:
872: . numDof - the number of dof

874:   Level: intermediate

876: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionSetFieldDof()`, `PetscSectionCreate()`
877: @*/
878: PetscErrorCode PetscSectionGetFieldDof(PetscSection s, PetscInt point, PetscInt field, PetscInt *numDof)
879: {
880:   PetscFunctionBegin;
883:   PetscSectionCheckValidField(field, s->numFields);
884:   PetscCall(PetscSectionGetDof(s->field[field], point, numDof));
885:   PetscFunctionReturn(PETSC_SUCCESS);
886: }

888: /*@
889:   PetscSectionSetFieldDof - Sets the number of degrees of freedom associated with a field on a given point.

891:   Not Collective

893:   Input Parameters:
894: + s - the `PetscSection`
895: . point - the point
896: . field - the field
897: - numDof - the number of dof

899:   Level: intermediate

901: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetFieldDof()`, `PetscSectionCreate()`
902: @*/
903: PetscErrorCode PetscSectionSetFieldDof(PetscSection s, PetscInt point, PetscInt field, PetscInt numDof)
904: {
905:   PetscFunctionBegin;
907:   PetscSectionCheckValidField(field, s->numFields);
908:   PetscCall(PetscSectionSetDof(s->field[field], point, numDof));
909:   PetscFunctionReturn(PETSC_SUCCESS);
910: }

912: /*@
913:   PetscSectionAddFieldDof - Adds a number of degrees of freedom associated with a field on a given point.

915:   Not Collective

917:   Input Parameters:
918: + s - the `PetscSection`
919: . point - the point
920: . field - the field
921: - numDof - the number of dof

923:   Level: intermediate

925: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionSetFieldDof()`, `PetscSectionGetFieldDof()`, `PetscSectionCreate()`
926: @*/
927: PetscErrorCode PetscSectionAddFieldDof(PetscSection s, PetscInt point, PetscInt field, PetscInt numDof)
928: {
929:   PetscFunctionBegin;
931:   PetscSectionCheckValidField(field, s->numFields);
932:   PetscCall(PetscSectionAddDof(s->field[field], point, numDof));
933:   PetscFunctionReturn(PETSC_SUCCESS);
934: }

936: /*@
937:   PetscSectionGetConstraintDof - Return the number of constrained degrees of freedom associated with a given point.

939:   Not Collective

941:   Input Parameters:
942: + s - the `PetscSection`
943: - point - the point

945:   Output Parameter:
946: . numDof - the number of dof which are fixed by constraints

948:   Level: intermediate

950: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetDof()`, `PetscSectionSetConstraintDof()`, `PetscSectionCreate()`
951: @*/
952: PetscErrorCode PetscSectionGetConstraintDof(PetscSection s, PetscInt point, PetscInt *numDof)
953: {
954:   PetscFunctionBegin;
957:   if (s->bc) {
958:     PetscCall(PetscSectionGetDof(s->bc, point, numDof));
959:   } else *numDof = 0;
960:   PetscFunctionReturn(PETSC_SUCCESS);
961: }

963: /*@
964:   PetscSectionSetConstraintDof - Set the number of constrained degrees of freedom associated with a given point.

966:   Not Collective

968:   Input Parameters:
969: + s - the `PetscSection`
970: . point - the point
971: - numDof - the number of dof which are fixed by constraints

973:   Level: intermediate

975: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionSetDof()`, `PetscSectionGetConstraintDof()`, `PetscSectionCreate()`
976: @*/
977: PetscErrorCode PetscSectionSetConstraintDof(PetscSection s, PetscInt point, PetscInt numDof)
978: {
979:   PetscFunctionBegin;
981:   if (numDof) {
982:     PetscCall(PetscSectionCheckConstraints_Private(s));
983:     PetscCall(PetscSectionSetDof(s->bc, point, numDof));
984:   }
985:   PetscFunctionReturn(PETSC_SUCCESS);
986: }

988: /*@
989:   PetscSectionAddConstraintDof - Increment the number of constrained degrees of freedom associated with a given point.

991:   Not Collective

993:   Input Parameters:
994: + s - the `PetscSection`
995: . point - the point
996: - numDof - the number of additional dof which are fixed by constraints

998:   Level: intermediate

1000: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionAddDof()`, `PetscSectionGetConstraintDof()`, `PetscSectionCreate()`
1001: @*/
1002: PetscErrorCode PetscSectionAddConstraintDof(PetscSection s, PetscInt point, PetscInt numDof)
1003: {
1004:   PetscFunctionBegin;
1006:   if (numDof) {
1007:     PetscCall(PetscSectionCheckConstraints_Private(s));
1008:     PetscCall(PetscSectionAddDof(s->bc, point, numDof));
1009:   }
1010:   PetscFunctionReturn(PETSC_SUCCESS);
1011: }

1013: /*@
1014:   PetscSectionGetFieldConstraintDof - Return the number of constrained degrees of freedom associated with a given field on a point.

1016:   Not Collective

1018:   Input Parameters:
1019: + s - the `PetscSection`
1020: . point - the point
1021: - field - the field

1023:   Output Parameter:
1024: . numDof - the number of dof which are fixed by constraints

1026:   Level: intermediate

1028: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetDof()`, `PetscSectionSetFieldConstraintDof()`, `PetscSectionCreate()`
1029: @*/
1030: PetscErrorCode PetscSectionGetFieldConstraintDof(PetscSection s, PetscInt point, PetscInt field, PetscInt *numDof)
1031: {
1032:   PetscFunctionBegin;
1035:   PetscSectionCheckValidField(field, s->numFields);
1036:   PetscCall(PetscSectionGetConstraintDof(s->field[field], point, numDof));
1037:   PetscFunctionReturn(PETSC_SUCCESS);
1038: }

1040: /*@
1041:   PetscSectionSetFieldConstraintDof - Set the number of constrained degrees of freedom associated with a given field on a point.

1043:   Not Collective

1045:   Input Parameters:
1046: + s - the `PetscSection`
1047: . point - the point
1048: . field - the field
1049: - numDof - the number of dof which are fixed by constraints

1051:   Level: intermediate

1053: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionSetDof()`, `PetscSectionGetFieldConstraintDof()`, `PetscSectionCreate()`
1054: @*/
1055: PetscErrorCode PetscSectionSetFieldConstraintDof(PetscSection s, PetscInt point, PetscInt field, PetscInt numDof)
1056: {
1057:   PetscFunctionBegin;
1059:   PetscSectionCheckValidField(field, s->numFields);
1060:   PetscCall(PetscSectionSetConstraintDof(s->field[field], point, numDof));
1061:   PetscFunctionReturn(PETSC_SUCCESS);
1062: }

1064: /*@
1065:   PetscSectionAddFieldConstraintDof - Increment the number of constrained degrees of freedom associated with a given field on a point.

1067:   Not Collective

1069:   Input Parameters:
1070: + s - the `PetscSection`
1071: . point - the point
1072: . field - the field
1073: - numDof - the number of additional dof which are fixed by constraints

1075:   Level: intermediate

1077: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionAddDof()`, `PetscSectionGetFieldConstraintDof()`, `PetscSectionCreate()`
1078: @*/
1079: PetscErrorCode PetscSectionAddFieldConstraintDof(PetscSection s, PetscInt point, PetscInt field, PetscInt numDof)
1080: {
1081:   PetscFunctionBegin;
1083:   PetscSectionCheckValidField(field, s->numFields);
1084:   PetscCall(PetscSectionAddConstraintDof(s->field[field], point, numDof));
1085:   PetscFunctionReturn(PETSC_SUCCESS);
1086: }

1088: /*@
1089:   PetscSectionSetUpBC - Setup the subsections describing boundary conditions.

1091:   Not Collective

1093:   Input Parameter:
1094: . s - the `PetscSection`

1096:   Level: advanced

1098: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionSetUp()`, `PetscSectionCreate()`
1099: @*/
1100: PetscErrorCode PetscSectionSetUpBC(PetscSection s)
1101: {
1102:   PetscFunctionBegin;
1104:   if (s->bc) {
1105:     const PetscInt last = (s->bc->pEnd - s->bc->pStart) - 1;

1107:     PetscCall(PetscSectionSetUp(s->bc));
1108:     PetscCall(PetscMalloc1((last >= 0 ? s->bc->atlasOff[last] + s->bc->atlasDof[last] : 0), &s->bcIndices));
1109:   }
1110:   PetscFunctionReturn(PETSC_SUCCESS);
1111: }

1113: /*@
1114:   PetscSectionSetUp - Calculate offsets based upon the number of degrees of freedom for each point.

1116:   Not Collective

1118:   Input Parameter:
1119: . s - the `PetscSection`

1121:   Level: intermediate

1123: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionCreate()`
1124: @*/
1125: PetscErrorCode PetscSectionSetUp(PetscSection s)
1126: {
1127:   const PetscInt *pind   = NULL;
1128:   PetscInt        offset = 0, foff, p, f;

1130:   PetscFunctionBegin;
1132:   if (s->setup) PetscFunctionReturn(PETSC_SUCCESS);
1133:   s->setup = PETSC_TRUE;
1134:   /* Set offsets and field offsets for all points */
1135:   /*   Assume that all fields have the same chart */
1136:   PetscCheck(s->includesConstraints, PETSC_COMM_SELF, PETSC_ERR_SUP, "PetscSectionSetUp is currently unsupported for includesConstraints = PETSC_TRUE");
1137:   if (s->perm) PetscCall(ISGetIndices(s->perm, &pind));
1138:   if (s->pointMajor) {
1139:     for (p = 0; p < s->pEnd - s->pStart; ++p) {
1140:       const PetscInt q = pind ? pind[p] : p;

1142:       /* Set point offset */
1143:       s->atlasOff[q] = offset;
1144:       offset += s->atlasDof[q];
1145:       /* Set field offset */
1146:       for (f = 0, foff = s->atlasOff[q]; f < s->numFields; ++f) {
1147:         PetscSection sf = s->field[f];

1149:         sf->atlasOff[q] = foff;
1150:         foff += sf->atlasDof[q];
1151:       }
1152:     }
1153:   } else {
1154:     /* Set field offsets for all points */
1155:     for (f = 0; f < s->numFields; ++f) {
1156:       PetscSection sf = s->field[f];

1158:       for (p = 0; p < s->pEnd - s->pStart; ++p) {
1159:         const PetscInt q = pind ? pind[p] : p;

1161:         sf->atlasOff[q] = offset;
1162:         offset += sf->atlasDof[q];
1163:       }
1164:     }
1165:     /* Disable point offsets since these are unused */
1166:     for (p = 0; p < s->pEnd - s->pStart; ++p) s->atlasOff[p] = -1;
1167:   }
1168:   if (s->perm) PetscCall(ISRestoreIndices(s->perm, &pind));
1169:   /* Setup BC sections */
1170:   PetscCall(PetscSectionSetUpBC(s));
1171:   for (f = 0; f < s->numFields; ++f) PetscCall(PetscSectionSetUpBC(s->field[f]));
1172:   PetscFunctionReturn(PETSC_SUCCESS);
1173: }

1175: /*@
1176:   PetscSectionGetMaxDof - Return the maximum number of degrees of freedom on any point in the chart

1178:   Not Collective

1180:   Input Parameters:
1181: . s - the `PetscSection`

1183:   Output Parameter:
1184: . maxDof - the maximum dof

1186:   Level: intermediate

1188:   Note:
1189:   The returned number is up-to-date without need for `PetscSectionSetUp()`.

1191:   Developer Note:
1192:   The returned number is calculated lazily and stashed.

1194:   A call to `PetscSectionInvalidateMaxDof_Internal()` invalidates the stashed value.

1196:   `PetscSectionInvalidateMaxDof_Internal()` is called in `PetscSectionSetDof()`, `PetscSectionAddDof()` and `PetscSectionReset()`

1198:   It should also be called every time atlasDof is modified directly.

1200: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetDof()`, `PetscSectionSetDof()`, `PetscSectionAddDof()`, `PetscSectionCreate()`
1201: @*/
1202: PetscErrorCode PetscSectionGetMaxDof(PetscSection s, PetscInt *maxDof)
1203: {
1204:   PetscInt p;

1206:   PetscFunctionBegin;
1209:   if (s->maxDof == PETSC_MIN_INT) {
1210:     s->maxDof = 0;
1211:     for (p = 0; p < s->pEnd - s->pStart; ++p) s->maxDof = PetscMax(s->maxDof, s->atlasDof[p]);
1212:   }
1213:   *maxDof = s->maxDof;
1214:   PetscFunctionReturn(PETSC_SUCCESS);
1215: }

1217: /*@
1218:   PetscSectionGetStorageSize - Return the size of an array or local Vec capable of holding all the degrees of freedom.

1220:   Not Collective

1222:   Input Parameter:
1223: . s - the `PetscSection`

1225:   Output Parameter:
1226: . size - the size of an array which can hold all the dofs

1228:   Level: intermediate

1230: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetOffset()`, `PetscSectionGetConstrainedStorageSize()`, `PetscSectionCreate()`
1231: @*/
1232: PetscErrorCode PetscSectionGetStorageSize(PetscSection s, PetscInt *size)
1233: {
1234:   PetscInt p, n = 0;

1236:   PetscFunctionBegin;
1239:   for (p = 0; p < s->pEnd - s->pStart; ++p) n += s->atlasDof[p] > 0 ? s->atlasDof[p] : 0;
1240:   *size = n;
1241:   PetscFunctionReturn(PETSC_SUCCESS);
1242: }

1244: /*@
1245:   PetscSectionGetConstrainedStorageSize - Return the size of an array or local `Vec` capable of holding all unconstrained degrees of freedom.

1247:   Not Collective

1249:   Input Parameter:
1250: . s - the `PetscSection`

1252:   Output Parameter:
1253: . size - the size of an array which can hold all unconstrained dofs

1255:   Level: intermediate

1257: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetStorageSize()`, `PetscSectionGetOffset()`, `PetscSectionCreate()`
1258: @*/
1259: PetscErrorCode PetscSectionGetConstrainedStorageSize(PetscSection s, PetscInt *size)
1260: {
1261:   PetscInt p, n = 0;

1263:   PetscFunctionBegin;
1266:   for (p = 0; p < s->pEnd - s->pStart; ++p) {
1267:     const PetscInt cdof = s->bc ? s->bc->atlasDof[p] : 0;
1268:     n += s->atlasDof[p] > 0 ? s->atlasDof[p] - cdof : 0;
1269:   }
1270:   *size = n;
1271:   PetscFunctionReturn(PETSC_SUCCESS);
1272: }

1274: /*@
1275:   PetscSectionCreateGlobalSection - Create a section describing the global field layout using
1276:   the local section and a `PetscSF` describing the section point overlap.

1278:   Input Parameters:
1279: + s - The `PetscSection` for the local field layout
1280: . sf - The `PetscSF` describing parallel layout of the section points (leaves are unowned local points)
1281: . includeConstraints - By default this is `PETSC_FALSE`, meaning that the global field vector will not possess constrained dofs
1282: - localOffsets - If `PETSC_TRUE`, use local rather than global offsets for the points

1284:   Output Parameter:
1285: . gsection - The `PetscSection` for the global field layout

1287:   Level: intermediate

1289:   Notes:
1290:   If we have a set of local sections defining the layout of a set of local vectors, and also a `PetscSF` to determine which section points are shared and the ownership, we can calculate a global section defining the parallel data layout, and the associated global vector.

1292:   This gives negative sizes and offsets to points not owned by this process

1294: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionCreate()`
1295: @*/
1296: PetscErrorCode PetscSectionCreateGlobalSection(PetscSection s, PetscSF sf, PetscBool includeConstraints, PetscBool localOffsets, PetscSection *gsection)
1297: {
1298:   PetscSection    gs;
1299:   const PetscInt *pind = NULL;
1300:   PetscInt       *recv = NULL, *neg = NULL;
1301:   PetscInt        pStart, pEnd, p, dof, cdof, off, foff, globalOff = 0, nroots, nlocal, maxleaf;
1302:   PetscInt        numFields, f, numComponents;

1304:   PetscFunctionBegin;
1310:   PetscCheck(s->pointMajor, PETSC_COMM_SELF, PETSC_ERR_SUP, "No support for field major ordering");
1311:   PetscCall(PetscSectionCreate(PetscObjectComm((PetscObject)s), &gs));
1312:   PetscCall(PetscSectionGetNumFields(s, &numFields));
1313:   if (numFields > 0) PetscCall(PetscSectionSetNumFields(gs, numFields));
1314:   PetscCall(PetscSectionGetChart(s, &pStart, &pEnd));
1315:   PetscCall(PetscSectionSetChart(gs, pStart, pEnd));
1316:   gs->includesConstraints = includeConstraints;
1317:   PetscCall(PetscSFGetGraph(sf, &nroots, NULL, NULL, NULL));
1318:   nlocal = nroots; /* The local/leaf space matches global/root space */
1319:   /* Must allocate for all points visible to SF, which may be more than this section */
1320:   if (nroots >= 0) { /* nroots < 0 means that the graph has not been set, only happens in serial */
1321:     PetscCall(PetscSFGetLeafRange(sf, NULL, &maxleaf));
1322:     PetscCheck(nroots >= pEnd, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "SF roots %" PetscInt_FMT " < pEnd %" PetscInt_FMT, nroots, pEnd);
1323:     PetscCheck(maxleaf < nroots, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Max local leaf %" PetscInt_FMT " >= nroots %" PetscInt_FMT, maxleaf, nroots);
1324:     PetscCall(PetscMalloc2(nroots, &neg, nlocal, &recv));
1325:     PetscCall(PetscArrayzero(neg, nroots));
1326:   }
1327:   /* Mark all local points with negative dof */
1328:   for (p = pStart; p < pEnd; ++p) {
1329:     PetscCall(PetscSectionGetDof(s, p, &dof));
1330:     PetscCall(PetscSectionSetDof(gs, p, dof));
1331:     PetscCall(PetscSectionGetConstraintDof(s, p, &cdof));
1332:     if (!includeConstraints && cdof > 0) PetscCall(PetscSectionSetConstraintDof(gs, p, cdof));
1333:     if (neg) neg[p] = -(dof + 1);
1334:   }
1335:   PetscCall(PetscSectionSetUpBC(gs));
1336:   if (gs->bcIndices) PetscCall(PetscArraycpy(gs->bcIndices, s->bcIndices, gs->bc->atlasOff[gs->bc->pEnd - gs->bc->pStart - 1] + gs->bc->atlasDof[gs->bc->pEnd - gs->bc->pStart - 1]));
1337:   if (nroots >= 0) {
1338:     PetscCall(PetscArrayzero(recv, nlocal));
1339:     PetscCall(PetscSFBcastBegin(sf, MPIU_INT, neg, recv, MPI_REPLACE));
1340:     PetscCall(PetscSFBcastEnd(sf, MPIU_INT, neg, recv, MPI_REPLACE));
1341:     for (p = pStart; p < pEnd; ++p) {
1342:       if (recv[p] < 0) {
1343:         gs->atlasDof[p - pStart] = recv[p];
1344:         PetscCall(PetscSectionGetDof(s, p, &dof));
1345:         PetscCheck(-(recv[p] + 1) == dof, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Global dof %" PetscInt_FMT " for point %" PetscInt_FMT " is not the unconstrained %" PetscInt_FMT, -(recv[p] + 1), p, dof);
1346:       }
1347:     }
1348:   }
1349:   /* Calculate new sizes, get process offset, and calculate point offsets */
1350:   if (s->perm) PetscCall(ISGetIndices(s->perm, &pind));
1351:   for (p = 0, off = 0; p < pEnd - pStart; ++p) {
1352:     const PetscInt q = pind ? pind[p] : p;

1354:     cdof            = (!includeConstraints && s->bc) ? s->bc->atlasDof[q] : 0;
1355:     gs->atlasOff[q] = off;
1356:     off += gs->atlasDof[q] > 0 ? gs->atlasDof[q] - cdof : 0;
1357:   }
1358:   if (!localOffsets) {
1359:     PetscCallMPI(MPI_Scan(&off, &globalOff, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)s)));
1360:     globalOff -= off;
1361:   }
1362:   for (p = pStart, off = 0; p < pEnd; ++p) {
1363:     gs->atlasOff[p - pStart] += globalOff;
1364:     if (neg) neg[p] = -(gs->atlasOff[p - pStart] + 1);
1365:   }
1366:   if (s->perm) PetscCall(ISRestoreIndices(s->perm, &pind));
1367:   /* Put in negative offsets for ghost points */
1368:   if (nroots >= 0) {
1369:     PetscCall(PetscArrayzero(recv, nlocal));
1370:     PetscCall(PetscSFBcastBegin(sf, MPIU_INT, neg, recv, MPI_REPLACE));
1371:     PetscCall(PetscSFBcastEnd(sf, MPIU_INT, neg, recv, MPI_REPLACE));
1372:     for (p = pStart; p < pEnd; ++p) {
1373:       if (recv[p] < 0) gs->atlasOff[p - pStart] = recv[p];
1374:     }
1375:   }
1376:   PetscCall(PetscFree2(neg, recv));
1377:   /* Set field dofs/offsets/constraints */
1378:   for (f = 0; f < numFields; ++f) {
1379:     gs->field[f]->includesConstraints = includeConstraints;
1380:     PetscCall(PetscSectionGetFieldComponents(s, f, &numComponents));
1381:     PetscCall(PetscSectionSetFieldComponents(gs, f, numComponents));
1382:   }
1383:   for (p = pStart; p < pEnd; ++p) {
1384:     PetscCall(PetscSectionGetOffset(gs, p, &off));
1385:     for (f = 0, foff = off; f < numFields; ++f) {
1386:       PetscCall(PetscSectionGetFieldConstraintDof(s, p, f, &cdof));
1387:       if (!includeConstraints && cdof > 0) PetscCall(PetscSectionSetFieldConstraintDof(gs, p, f, cdof));
1388:       PetscCall(PetscSectionGetFieldDof(s, p, f, &dof));
1389:       PetscCall(PetscSectionSetFieldDof(gs, p, f, off < 0 ? -(dof + 1) : dof));
1390:       PetscCall(PetscSectionSetFieldOffset(gs, p, f, foff));
1391:       PetscCall(PetscSectionGetFieldConstraintDof(gs, p, f, &cdof));
1392:       foff = off < 0 ? foff - (dof - cdof) : foff + (dof - cdof);
1393:     }
1394:   }
1395:   for (f = 0; f < numFields; ++f) {
1396:     PetscSection gfs = gs->field[f];

1398:     PetscCall(PetscSectionSetUpBC(gfs));
1399:     if (gfs->bcIndices) PetscCall(PetscArraycpy(gfs->bcIndices, s->field[f]->bcIndices, gfs->bc->atlasOff[gfs->bc->pEnd - gfs->bc->pStart - 1] + gfs->bc->atlasDof[gfs->bc->pEnd - gfs->bc->pStart - 1]));
1400:   }
1401:   gs->setup = PETSC_TRUE;
1402:   PetscCall(PetscSectionViewFromOptions(gs, NULL, "-global_section_view"));
1403:   *gsection = gs;
1404:   PetscFunctionReturn(PETSC_SUCCESS);
1405: }

1407: /*@
1408:   PetscSectionCreateGlobalSectionCensored - Create a `PetscSection` describing the global field layout using
1409:   the local section and an `PetscSF` describing the section point overlap.

1411:   Input Parameters:
1412: + s - The `PetscSection` for the local field layout
1413: . sf - The `PetscSF` describing parallel layout of the section points
1414: . includeConstraints - By default this is `PETSC_FALSE`, meaning that the global field vector will not possess constrained dofs
1415: . numExcludes - The number of exclusion ranges
1416: - excludes - An array [start_0, end_0, start_1, end_1, ...] where there are numExcludes pairs

1418:   Output Parameter:
1419: . gsection - The `PetscSection` for the global field layout

1421:   Level: advanced

1423:   Note:
1424:   This gives negative sizes and offsets to points not owned by this process

1426: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionCreate()`
1427: @*/
1428: PetscErrorCode PetscSectionCreateGlobalSectionCensored(PetscSection s, PetscSF sf, PetscBool includeConstraints, PetscInt numExcludes, const PetscInt excludes[], PetscSection *gsection)
1429: {
1430:   const PetscInt *pind = NULL;
1431:   PetscInt       *neg = NULL, *tmpOff = NULL;
1432:   PetscInt        pStart, pEnd, p, e, dof, cdof, off, globalOff = 0, nroots;

1434:   PetscFunctionBegin;
1438:   PetscCall(PetscSectionCreate(PetscObjectComm((PetscObject)s), gsection));
1439:   PetscCall(PetscSectionGetChart(s, &pStart, &pEnd));
1440:   PetscCall(PetscSectionSetChart(*gsection, pStart, pEnd));
1441:   PetscCall(PetscSFGetGraph(sf, &nroots, NULL, NULL, NULL));
1442:   if (nroots >= 0) {
1443:     PetscCheck(nroots >= pEnd - pStart, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "PetscSF nroots %" PetscInt_FMT " < %" PetscInt_FMT " section size", nroots, pEnd - pStart);
1444:     PetscCall(PetscCalloc1(nroots, &neg));
1445:     if (nroots > pEnd - pStart) {
1446:       PetscCall(PetscCalloc1(nroots, &tmpOff));
1447:     } else {
1448:       tmpOff = &(*gsection)->atlasDof[-pStart];
1449:     }
1450:   }
1451:   /* Mark ghost points with negative dof */
1452:   for (p = pStart; p < pEnd; ++p) {
1453:     for (e = 0; e < numExcludes; ++e) {
1454:       if ((p >= excludes[e * 2 + 0]) && (p < excludes[e * 2 + 1])) {
1455:         PetscCall(PetscSectionSetDof(*gsection, p, 0));
1456:         break;
1457:       }
1458:     }
1459:     if (e < numExcludes) continue;
1460:     PetscCall(PetscSectionGetDof(s, p, &dof));
1461:     PetscCall(PetscSectionSetDof(*gsection, p, dof));
1462:     PetscCall(PetscSectionGetConstraintDof(s, p, &cdof));
1463:     if (!includeConstraints && cdof > 0) PetscCall(PetscSectionSetConstraintDof(*gsection, p, cdof));
1464:     if (neg) neg[p] = -(dof + 1);
1465:   }
1466:   PetscCall(PetscSectionSetUpBC(*gsection));
1467:   if (nroots >= 0) {
1468:     PetscCall(PetscSFBcastBegin(sf, MPIU_INT, neg, tmpOff, MPI_REPLACE));
1469:     PetscCall(PetscSFBcastEnd(sf, MPIU_INT, neg, tmpOff, MPI_REPLACE));
1470:     if (nroots > pEnd - pStart) {
1471:       for (p = pStart; p < pEnd; ++p) {
1472:         if (tmpOff[p] < 0) (*gsection)->atlasDof[p - pStart] = tmpOff[p];
1473:       }
1474:     }
1475:   }
1476:   /* Calculate new sizes, get process offset, and calculate point offsets */
1477:   if (s->perm) PetscCall(ISGetIndices(s->perm, &pind));
1478:   for (p = 0, off = 0; p < pEnd - pStart; ++p) {
1479:     const PetscInt q = pind ? pind[p] : p;

1481:     cdof                     = (!includeConstraints && s->bc) ? s->bc->atlasDof[q] : 0;
1482:     (*gsection)->atlasOff[q] = off;
1483:     off += (*gsection)->atlasDof[q] > 0 ? (*gsection)->atlasDof[q] - cdof : 0;
1484:   }
1485:   PetscCallMPI(MPI_Scan(&off, &globalOff, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)s)));
1486:   globalOff -= off;
1487:   for (p = 0, off = 0; p < pEnd - pStart; ++p) {
1488:     (*gsection)->atlasOff[p] += globalOff;
1489:     if (neg) neg[p + pStart] = -((*gsection)->atlasOff[p] + 1);
1490:   }
1491:   if (s->perm) PetscCall(ISRestoreIndices(s->perm, &pind));
1492:   /* Put in negative offsets for ghost points */
1493:   if (nroots >= 0) {
1494:     if (nroots == pEnd - pStart) tmpOff = &(*gsection)->atlasOff[-pStart];
1495:     PetscCall(PetscSFBcastBegin(sf, MPIU_INT, neg, tmpOff, MPI_REPLACE));
1496:     PetscCall(PetscSFBcastEnd(sf, MPIU_INT, neg, tmpOff, MPI_REPLACE));
1497:     if (nroots > pEnd - pStart) {
1498:       for (p = pStart; p < pEnd; ++p) {
1499:         if (tmpOff[p] < 0) (*gsection)->atlasOff[p - pStart] = tmpOff[p];
1500:       }
1501:     }
1502:   }
1503:   if (nroots >= 0 && nroots > pEnd - pStart) PetscCall(PetscFree(tmpOff));
1504:   PetscCall(PetscFree(neg));
1505:   PetscFunctionReturn(PETSC_SUCCESS);
1506: }

1508: /*@
1509:   PetscSectionGetPointLayout - Get the `PetscLayout` associated with the section points

1511:   Collective

1513:   Input Parameters:
1514: + comm - The `MPI_Comm`
1515: - s    - The `PetscSection`

1517:   Output Parameter:
1518: . layout - The point layout for the section

1520:   Level: advanced

1522:   Note:
1523:   This is usually called for the default global section.

1525: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetValueLayout()`, `PetscSectionCreate()`
1526: @*/
1527: PetscErrorCode PetscSectionGetPointLayout(MPI_Comm comm, PetscSection s, PetscLayout *layout)
1528: {
1529:   PetscInt pStart, pEnd, p, localSize = 0;

1531:   PetscFunctionBegin;
1532:   PetscCall(PetscSectionGetChart(s, &pStart, &pEnd));
1533:   for (p = pStart; p < pEnd; ++p) {
1534:     PetscInt dof;

1536:     PetscCall(PetscSectionGetDof(s, p, &dof));
1537:     if (dof >= 0) ++localSize;
1538:   }
1539:   PetscCall(PetscLayoutCreate(comm, layout));
1540:   PetscCall(PetscLayoutSetLocalSize(*layout, localSize));
1541:   PetscCall(PetscLayoutSetBlockSize(*layout, 1));
1542:   PetscCall(PetscLayoutSetUp(*layout));
1543:   PetscFunctionReturn(PETSC_SUCCESS);
1544: }

1546: /*@
1547:   PetscSectionGetValueLayout - Get the `PetscLayout` associated with the section dofs.

1549:   Collective

1551:   Input Parameters:
1552: + comm - The `MPI_Comm`
1553: - s    - The `PetscSection`

1555:   Output Parameter:
1556: . layout - The dof layout for the section

1558:   Level: advanced

1560:   Note:
1561:   This is usually called for the default global section.

1563: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetPointLayout()`, `PetscSectionCreate()`
1564: @*/
1565: PetscErrorCode PetscSectionGetValueLayout(MPI_Comm comm, PetscSection s, PetscLayout *layout)
1566: {
1567:   PetscInt pStart, pEnd, p, localSize = 0;

1569:   PetscFunctionBegin;
1572:   PetscCall(PetscSectionGetChart(s, &pStart, &pEnd));
1573:   for (p = pStart; p < pEnd; ++p) {
1574:     PetscInt dof, cdof;

1576:     PetscCall(PetscSectionGetDof(s, p, &dof));
1577:     PetscCall(PetscSectionGetConstraintDof(s, p, &cdof));
1578:     if (dof - cdof > 0) localSize += dof - cdof;
1579:   }
1580:   PetscCall(PetscLayoutCreate(comm, layout));
1581:   PetscCall(PetscLayoutSetLocalSize(*layout, localSize));
1582:   PetscCall(PetscLayoutSetBlockSize(*layout, 1));
1583:   PetscCall(PetscLayoutSetUp(*layout));
1584:   PetscFunctionReturn(PETSC_SUCCESS);
1585: }

1587: /*@
1588:   PetscSectionGetOffset - Return the offset into an array or `Vec` for the dof associated with the given point.

1590:   Not Collective

1592:   Input Parameters:
1593: + s - the `PetscSection`
1594: - point - the point

1596:   Output Parameter:
1597: . offset - the offset

1599:   Note:
1600:   In a global section, this offset will be negative for points not owned by this process.

1602:   Level: intermediate

1604: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetFieldOffset()`, `PetscSectionCreate()`
1605: @*/
1606: PetscErrorCode PetscSectionGetOffset(PetscSection s, PetscInt point, PetscInt *offset)
1607: {
1608:   PetscFunctionBegin;
1611:   if (PetscDefined(USE_DEBUG)) PetscCheck(!(point < s->pStart) && !(point >= s->pEnd), PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Section point %" PetscInt_FMT " should be in [%" PetscInt_FMT ", %" PetscInt_FMT ")", point, s->pStart, s->pEnd);
1612:   *offset = s->atlasOff[point - s->pStart];
1613:   PetscFunctionReturn(PETSC_SUCCESS);
1614: }

1616: /*@
1617:   PetscSectionSetOffset - Set the offset into an array or `Vec` for the dof associated with the given point.

1619:   Not Collective

1621:   Input Parameters:
1622: + s - the `PetscSection`
1623: . point - the point
1624: - offset - the offset

1626:   Level: intermediate

1628:   Note:
1629:   The user usually does not call this function, but uses `PetscSectionSetUp()`

1631: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetFieldOffset()`, `PetscSectionCreate()`, `PetscSectionSetUp()`
1632: @*/
1633: PetscErrorCode PetscSectionSetOffset(PetscSection s, PetscInt point, PetscInt offset)
1634: {
1635:   PetscFunctionBegin;
1637:   PetscCheck(!(point < s->pStart) && !(point >= s->pEnd), PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Section point %" PetscInt_FMT " should be in [%" PetscInt_FMT ", %" PetscInt_FMT ")", point, s->pStart, s->pEnd);
1638:   s->atlasOff[point - s->pStart] = offset;
1639:   PetscFunctionReturn(PETSC_SUCCESS);
1640: }

1642: /*@
1643:   PetscSectionGetFieldOffset - Return the offset into an array or `Vec` for the field dof associated with the given point.

1645:   Not Collective

1647:   Input Parameters:
1648: + s - the `PetscSection`
1649: . point - the point
1650: - field - the field

1652:   Output Parameter:
1653: . offset - the offset

1655:   Note:
1656:   In a global section, this offset will be negative for points not owned by this process.

1658:   Level: intermediate

1660: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetOffset()`, `PetscSectionCreate()`
1661: @*/
1662: PetscErrorCode PetscSectionGetFieldOffset(PetscSection s, PetscInt point, PetscInt field, PetscInt *offset)
1663: {
1664:   PetscFunctionBegin;
1667:   PetscSectionCheckValidField(field, s->numFields);
1668:   PetscCall(PetscSectionGetOffset(s->field[field], point, offset));
1669:   PetscFunctionReturn(PETSC_SUCCESS);
1670: }

1672: /*@
1673:   PetscSectionSetFieldOffset - Set the offset into an array or `Vec` for the dof associated with the given field at a point.

1675:   Not Collective

1677:   Input Parameters:
1678: + s - the PetscSection
1679: . point - the point
1680: . field - the field
1681: - offset - the offset

1683:   Level: developer

1685:   Note:
1686:   The user usually does not call this function, but uses `PetscSectionSetUp()`

1688: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetFieldOffset()`, `PetscSectionSetOffset()`, `PetscSectionCreate()`, `PetscSectionSetUp()`
1689: @*/
1690: PetscErrorCode PetscSectionSetFieldOffset(PetscSection s, PetscInt point, PetscInt field, PetscInt offset)
1691: {
1692:   PetscFunctionBegin;
1694:   PetscSectionCheckValidField(field, s->numFields);
1695:   PetscCall(PetscSectionSetOffset(s->field[field], point, offset));
1696:   PetscFunctionReturn(PETSC_SUCCESS);
1697: }

1699: /*@
1700:   PetscSectionGetFieldPointOffset - Return the offset on the given point for the dof associated with the given point.

1702:   Not Collective

1704:   Input Parameters:
1705: + s - the `PetscSection`
1706: . point - the point
1707: - field - the field

1709:   Output Parameter:
1710: . offset - the offset

1712:   Level: advanced

1714:   Note:
1715:   This gives the offset on a point of the field, ignoring constraints, meaning starting at the first dof for
1716:   this point, what number is the first dof with this field.

1718: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetOffset()`, `PetscSectionCreate()`
1719: @*/
1720: PetscErrorCode PetscSectionGetFieldPointOffset(PetscSection s, PetscInt point, PetscInt field, PetscInt *offset)
1721: {
1722:   PetscInt off, foff;

1724:   PetscFunctionBegin;
1727:   PetscSectionCheckValidField(field, s->numFields);
1728:   PetscCall(PetscSectionGetOffset(s, point, &off));
1729:   PetscCall(PetscSectionGetOffset(s->field[field], point, &foff));
1730:   *offset = foff - off;
1731:   PetscFunctionReturn(PETSC_SUCCESS);
1732: }

1734: /*@
1735:   PetscSectionGetOffsetRange - Return the full range of offsets [start, end)

1737:   Not Collective

1739:   Input Parameter:
1740: . s - the `PetscSection`

1742:   Output Parameters:
1743: + start - the minimum offset
1744: - end   - one more than the maximum offset

1746:   Level: intermediate

1748: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetOffset()`, `PetscSectionCreate()`
1749: @*/
1750: PetscErrorCode PetscSectionGetOffsetRange(PetscSection s, PetscInt *start, PetscInt *end)
1751: {
1752:   PetscInt os = 0, oe = 0, pStart, pEnd, p;

1754:   PetscFunctionBegin;
1756:   if (s->atlasOff) {
1757:     os = s->atlasOff[0];
1758:     oe = s->atlasOff[0];
1759:   }
1760:   PetscCall(PetscSectionGetChart(s, &pStart, &pEnd));
1761:   for (p = 0; p < pEnd - pStart; ++p) {
1762:     PetscInt dof = s->atlasDof[p], off = s->atlasOff[p];

1764:     if (off >= 0) {
1765:       os = PetscMin(os, off);
1766:       oe = PetscMax(oe, off + dof);
1767:     }
1768:   }
1769:   if (start) *start = os;
1770:   if (end) *end = oe;
1771:   PetscFunctionReturn(PETSC_SUCCESS);
1772: }

1774: /*@
1775:   PetscSectionCreateSubsection - Create a new, smaller section composed of only the selected fields

1777:   Collective

1779:   Input Parameters:
1780: + s      - the `PetscSection`
1781: . len    - the number of subfields
1782: - fields - the subfield numbers

1784:   Output Parameter:
1785: . subs   - the subsection

1787:   Level: advanced

1789:   Notes:
1790:   The section offsets now refer to a new, smaller vector.

1792:   This will error if a fieldnumber is out of range

1794: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionCreateSupersection()`, `PetscSectionCreate()`
1795: @*/
1796: PetscErrorCode PetscSectionCreateSubsection(PetscSection s, PetscInt len, const PetscInt fields[], PetscSection *subs)
1797: {
1798:   PetscInt nF, f, c, pStart, pEnd, p, maxCdof = 0;

1800:   PetscFunctionBegin;
1801:   if (!len) PetscFunctionReturn(PETSC_SUCCESS);
1805:   PetscCall(PetscSectionGetNumFields(s, &nF));
1806:   PetscCheck(len <= nF, PetscObjectComm((PetscObject)s), PETSC_ERR_ARG_WRONG, "Number of requested fields %" PetscInt_FMT " greater than number of fields %" PetscInt_FMT, len, nF);
1807:   PetscCall(PetscSectionCreate(PetscObjectComm((PetscObject)s), subs));
1808:   PetscCall(PetscSectionSetNumFields(*subs, len));
1809:   for (f = 0; f < len; ++f) {
1810:     const char *name    = NULL;
1811:     PetscInt    numComp = 0;

1813:     PetscCall(PetscSectionGetFieldName(s, fields[f], &name));
1814:     PetscCall(PetscSectionSetFieldName(*subs, f, name));
1815:     PetscCall(PetscSectionGetFieldComponents(s, fields[f], &numComp));
1816:     PetscCall(PetscSectionSetFieldComponents(*subs, f, numComp));
1817:     for (c = 0; c < s->numFieldComponents[fields[f]]; ++c) {
1818:       PetscCall(PetscSectionGetComponentName(s, fields[f], c, &name));
1819:       PetscCall(PetscSectionSetComponentName(*subs, f, c, name));
1820:     }
1821:   }
1822:   PetscCall(PetscSectionGetChart(s, &pStart, &pEnd));
1823:   PetscCall(PetscSectionSetChart(*subs, pStart, pEnd));
1824:   for (p = pStart; p < pEnd; ++p) {
1825:     PetscInt dof = 0, cdof = 0, fdof = 0, cfdof = 0;

1827:     for (f = 0; f < len; ++f) {
1828:       PetscCall(PetscSectionGetFieldDof(s, p, fields[f], &fdof));
1829:       PetscCall(PetscSectionSetFieldDof(*subs, p, f, fdof));
1830:       PetscCall(PetscSectionGetFieldConstraintDof(s, p, fields[f], &cfdof));
1831:       if (cfdof) PetscCall(PetscSectionSetFieldConstraintDof(*subs, p, f, cfdof));
1832:       dof += fdof;
1833:       cdof += cfdof;
1834:     }
1835:     PetscCall(PetscSectionSetDof(*subs, p, dof));
1836:     if (cdof) PetscCall(PetscSectionSetConstraintDof(*subs, p, cdof));
1837:     maxCdof = PetscMax(cdof, maxCdof);
1838:   }
1839:   PetscCall(PetscSectionSetUp(*subs));
1840:   if (maxCdof) {
1841:     PetscInt *indices;

1843:     PetscCall(PetscMalloc1(maxCdof, &indices));
1844:     for (p = pStart; p < pEnd; ++p) {
1845:       PetscInt cdof;

1847:       PetscCall(PetscSectionGetConstraintDof(*subs, p, &cdof));
1848:       if (cdof) {
1849:         const PetscInt *oldIndices = NULL;
1850:         PetscInt        fdof = 0, cfdof = 0, fc, numConst = 0, fOff = 0;

1852:         for (f = 0; f < len; ++f) {
1853:           PetscCall(PetscSectionGetFieldDof(s, p, fields[f], &fdof));
1854:           PetscCall(PetscSectionGetFieldConstraintDof(s, p, fields[f], &cfdof));
1855:           PetscCall(PetscSectionGetFieldConstraintIndices(s, p, fields[f], &oldIndices));
1856:           PetscCall(PetscSectionSetFieldConstraintIndices(*subs, p, f, oldIndices));
1857:           for (fc = 0; fc < cfdof; ++fc) indices[numConst + fc] = oldIndices[fc] + fOff;
1858:           numConst += cfdof;
1859:           fOff += fdof;
1860:         }
1861:         PetscCall(PetscSectionSetConstraintIndices(*subs, p, indices));
1862:       }
1863:     }
1864:     PetscCall(PetscFree(indices));
1865:   }
1866:   PetscFunctionReturn(PETSC_SUCCESS);
1867: }

1869: /*@
1870:   PetscSectionCreateSupersection - Create a new, larger section composed of the input sections

1872:   Collective

1874:   Input Parameters:
1875: + s     - the input sections
1876: - len   - the number of input sections

1878:   Output Parameter:
1879: . supers - the supersection

1881:   Level: advanced

1883:   Note:
1884:   The section offsets now refer to a new, larger vector.

1886:   Developer Note:
1887:   Needs to explain how the sections are composed

1889: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionCreateSubsection()`, `PetscSectionCreate()`
1890: @*/
1891: PetscErrorCode PetscSectionCreateSupersection(PetscSection s[], PetscInt len, PetscSection *supers)
1892: {
1893:   PetscInt Nf = 0, f, pStart = PETSC_MAX_INT, pEnd = 0, p, maxCdof = 0, i;

1895:   PetscFunctionBegin;
1896:   if (!len) PetscFunctionReturn(PETSC_SUCCESS);
1897:   for (i = 0; i < len; ++i) {
1898:     PetscInt nf, pStarti, pEndi;

1900:     PetscCall(PetscSectionGetNumFields(s[i], &nf));
1901:     PetscCall(PetscSectionGetChart(s[i], &pStarti, &pEndi));
1902:     pStart = PetscMin(pStart, pStarti);
1903:     pEnd   = PetscMax(pEnd, pEndi);
1904:     Nf += nf;
1905:   }
1906:   PetscCall(PetscSectionCreate(PetscObjectComm((PetscObject)s[0]), supers));
1907:   PetscCall(PetscSectionSetNumFields(*supers, Nf));
1908:   for (i = 0, f = 0; i < len; ++i) {
1909:     PetscInt nf, fi, ci;

1911:     PetscCall(PetscSectionGetNumFields(s[i], &nf));
1912:     for (fi = 0; fi < nf; ++fi, ++f) {
1913:       const char *name    = NULL;
1914:       PetscInt    numComp = 0;

1916:       PetscCall(PetscSectionGetFieldName(s[i], fi, &name));
1917:       PetscCall(PetscSectionSetFieldName(*supers, f, name));
1918:       PetscCall(PetscSectionGetFieldComponents(s[i], fi, &numComp));
1919:       PetscCall(PetscSectionSetFieldComponents(*supers, f, numComp));
1920:       for (ci = 0; ci < s[i]->numFieldComponents[fi]; ++ci) {
1921:         PetscCall(PetscSectionGetComponentName(s[i], fi, ci, &name));
1922:         PetscCall(PetscSectionSetComponentName(*supers, f, ci, name));
1923:       }
1924:     }
1925:   }
1926:   PetscCall(PetscSectionSetChart(*supers, pStart, pEnd));
1927:   for (p = pStart; p < pEnd; ++p) {
1928:     PetscInt dof = 0, cdof = 0;

1930:     for (i = 0, f = 0; i < len; ++i) {
1931:       PetscInt nf, fi, pStarti, pEndi;
1932:       PetscInt fdof = 0, cfdof = 0;

1934:       PetscCall(PetscSectionGetNumFields(s[i], &nf));
1935:       PetscCall(PetscSectionGetChart(s[i], &pStarti, &pEndi));
1936:       if ((p < pStarti) || (p >= pEndi)) continue;
1937:       for (fi = 0; fi < nf; ++fi, ++f) {
1938:         PetscCall(PetscSectionGetFieldDof(s[i], p, fi, &fdof));
1939:         PetscCall(PetscSectionAddFieldDof(*supers, p, f, fdof));
1940:         PetscCall(PetscSectionGetFieldConstraintDof(s[i], p, fi, &cfdof));
1941:         if (cfdof) PetscCall(PetscSectionAddFieldConstraintDof(*supers, p, f, cfdof));
1942:         dof += fdof;
1943:         cdof += cfdof;
1944:       }
1945:     }
1946:     PetscCall(PetscSectionSetDof(*supers, p, dof));
1947:     if (cdof) PetscCall(PetscSectionSetConstraintDof(*supers, p, cdof));
1948:     maxCdof = PetscMax(cdof, maxCdof);
1949:   }
1950:   PetscCall(PetscSectionSetUp(*supers));
1951:   if (maxCdof) {
1952:     PetscInt *indices;

1954:     PetscCall(PetscMalloc1(maxCdof, &indices));
1955:     for (p = pStart; p < pEnd; ++p) {
1956:       PetscInt cdof;

1958:       PetscCall(PetscSectionGetConstraintDof(*supers, p, &cdof));
1959:       if (cdof) {
1960:         PetscInt dof, numConst = 0, fOff = 0;

1962:         for (i = 0, f = 0; i < len; ++i) {
1963:           const PetscInt *oldIndices = NULL;
1964:           PetscInt        nf, fi, pStarti, pEndi, fdof, cfdof, fc;

1966:           PetscCall(PetscSectionGetNumFields(s[i], &nf));
1967:           PetscCall(PetscSectionGetChart(s[i], &pStarti, &pEndi));
1968:           if ((p < pStarti) || (p >= pEndi)) continue;
1969:           for (fi = 0; fi < nf; ++fi, ++f) {
1970:             PetscCall(PetscSectionGetFieldDof(s[i], p, fi, &fdof));
1971:             PetscCall(PetscSectionGetFieldConstraintDof(s[i], p, fi, &cfdof));
1972:             PetscCall(PetscSectionGetFieldConstraintIndices(s[i], p, fi, &oldIndices));
1973:             for (fc = 0; fc < cfdof; ++fc) indices[numConst + fc] = oldIndices[fc];
1974:             PetscCall(PetscSectionSetFieldConstraintIndices(*supers, p, f, &indices[numConst]));
1975:             for (fc = 0; fc < cfdof; ++fc) indices[numConst + fc] += fOff;
1976:             numConst += cfdof;
1977:           }
1978:           PetscCall(PetscSectionGetDof(s[i], p, &dof));
1979:           fOff += dof;
1980:         }
1981:         PetscCall(PetscSectionSetConstraintIndices(*supers, p, indices));
1982:       }
1983:     }
1984:     PetscCall(PetscFree(indices));
1985:   }
1986:   PetscFunctionReturn(PETSC_SUCCESS);
1987: }

1989: PetscErrorCode PetscSectionCreateSubplexSection_Internal(PetscSection s, IS subpointMap, PetscBool renumberPoints, PetscSection *subs)
1990: {
1991:   const PetscInt *points = NULL, *indices = NULL;
1992:   PetscInt        numFields, f, c, numSubpoints = 0, pStart, pEnd, p, spStart, spEnd, subp;

1994:   PetscFunctionBegin;
1998:   PetscCall(PetscSectionGetNumFields(s, &numFields));
1999:   PetscCall(PetscSectionCreate(PetscObjectComm((PetscObject)s), subs));
2000:   if (numFields) PetscCall(PetscSectionSetNumFields(*subs, numFields));
2001:   for (f = 0; f < numFields; ++f) {
2002:     const char *name    = NULL;
2003:     PetscInt    numComp = 0;

2005:     PetscCall(PetscSectionGetFieldName(s, f, &name));
2006:     PetscCall(PetscSectionSetFieldName(*subs, f, name));
2007:     PetscCall(PetscSectionGetFieldComponents(s, f, &numComp));
2008:     PetscCall(PetscSectionSetFieldComponents(*subs, f, numComp));
2009:     for (c = 0; c < s->numFieldComponents[f]; ++c) {
2010:       PetscCall(PetscSectionGetComponentName(s, f, c, &name));
2011:       PetscCall(PetscSectionSetComponentName(*subs, f, c, name));
2012:     }
2013:   }
2014:   /* For right now, we do not try to squeeze the subchart */
2015:   if (subpointMap) {
2016:     PetscCall(ISGetSize(subpointMap, &numSubpoints));
2017:     PetscCall(ISGetIndices(subpointMap, &points));
2018:   }
2019:   PetscCall(PetscSectionGetChart(s, &pStart, &pEnd));
2020:   if (renumberPoints) {
2021:     spStart = 0;
2022:     spEnd   = numSubpoints;
2023:   } else {
2024:     PetscCall(ISGetMinMax(subpointMap, &spStart, &spEnd));
2025:     ++spEnd;
2026:   }
2027:   PetscCall(PetscSectionSetChart(*subs, spStart, spEnd));
2028:   for (p = pStart; p < pEnd; ++p) {
2029:     PetscInt dof, cdof, fdof = 0, cfdof = 0;

2031:     PetscCall(PetscFindInt(p, numSubpoints, points, &subp));
2032:     if (subp < 0) continue;
2033:     if (!renumberPoints) subp = p;
2034:     for (f = 0; f < numFields; ++f) {
2035:       PetscCall(PetscSectionGetFieldDof(s, p, f, &fdof));
2036:       PetscCall(PetscSectionSetFieldDof(*subs, subp, f, fdof));
2037:       PetscCall(PetscSectionGetFieldConstraintDof(s, p, f, &cfdof));
2038:       if (cfdof) PetscCall(PetscSectionSetFieldConstraintDof(*subs, subp, f, cfdof));
2039:     }
2040:     PetscCall(PetscSectionGetDof(s, p, &dof));
2041:     PetscCall(PetscSectionSetDof(*subs, subp, dof));
2042:     PetscCall(PetscSectionGetConstraintDof(s, p, &cdof));
2043:     if (cdof) PetscCall(PetscSectionSetConstraintDof(*subs, subp, cdof));
2044:   }
2045:   PetscCall(PetscSectionSetUp(*subs));
2046:   /* Change offsets to original offsets */
2047:   for (p = pStart; p < pEnd; ++p) {
2048:     PetscInt off, foff = 0;

2050:     PetscCall(PetscFindInt(p, numSubpoints, points, &subp));
2051:     if (subp < 0) continue;
2052:     if (!renumberPoints) subp = p;
2053:     for (f = 0; f < numFields; ++f) {
2054:       PetscCall(PetscSectionGetFieldOffset(s, p, f, &foff));
2055:       PetscCall(PetscSectionSetFieldOffset(*subs, subp, f, foff));
2056:     }
2057:     PetscCall(PetscSectionGetOffset(s, p, &off));
2058:     PetscCall(PetscSectionSetOffset(*subs, subp, off));
2059:   }
2060:   /* Copy constraint indices */
2061:   for (subp = spStart; subp < spEnd; ++subp) {
2062:     PetscInt cdof;

2064:     PetscCall(PetscSectionGetConstraintDof(*subs, subp, &cdof));
2065:     if (cdof) {
2066:       for (f = 0; f < numFields; ++f) {
2067:         PetscCall(PetscSectionGetFieldConstraintIndices(s, points[subp - spStart], f, &indices));
2068:         PetscCall(PetscSectionSetFieldConstraintIndices(*subs, subp, f, indices));
2069:       }
2070:       PetscCall(PetscSectionGetConstraintIndices(s, points[subp - spStart], &indices));
2071:       PetscCall(PetscSectionSetConstraintIndices(*subs, subp, indices));
2072:     }
2073:   }
2074:   if (subpointMap) PetscCall(ISRestoreIndices(subpointMap, &points));
2075:   PetscFunctionReturn(PETSC_SUCCESS);
2076: }

2078: /*@
2079:   PetscSectionCreateSubmeshSection - Create a new, smaller section with support on the submesh

2081:   Collective

2083:   Input Parameters:
2084: + s           - the `PetscSection`
2085: - subpointMap - a sorted list of points in the original mesh which are in the submesh

2087:   Output Parameter:
2088: . subs - the subsection

2090:   Level: advanced

2092:   Note:
2093:   The points are renumbered from 0, and the section offsets now refer to a new, smaller vector.

2095:   Developer Note:
2096:   The use of the term Submesh is confusing and unneeded

2098: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionCreateSubdomainSection()`, `PetscSectionCreateSubsection()`, `DMPlexGetSubpointMap()`, `PetscSectionCreate()`
2099: @*/
2100: PetscErrorCode PetscSectionCreateSubmeshSection(PetscSection s, IS subpointMap, PetscSection *subs)
2101: {
2102:   PetscFunctionBegin;
2103:   PetscCall(PetscSectionCreateSubplexSection_Internal(s, subpointMap, PETSC_TRUE, subs));
2104:   PetscFunctionReturn(PETSC_SUCCESS);
2105: }

2107: /*@
2108:   PetscSectionCreateSubdomainSection - Create a new, smaller section with support on a subdomain of the mesh

2110:   Collective

2112:   Input Parameters:
2113: + s           - the `PetscSection`
2114: - subpointMap - a sorted list of points in the original mesh which are in the subdomain

2116:   Output Parameter:
2117: . subs - the subsection

2119:   Level: advanced

2121:   Note:
2122:   The point numbers remain the same, but the section offsets now refer to a new, smaller vector.

2124:   Developer Notes:
2125:   It is unclear what the difference with `PetscSectionCreateSubmeshSection()` is.

2127:   The use of the term Subdomain is unneeded and confusing

2129: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionCreateSubmeshSection()`, `PetscSectionCreateSubsection()`, `DMPlexGetSubpointMap()`, `PetscSectionCreate()`
2130: @*/
2131: PetscErrorCode PetscSectionCreateSubdomainSection(PetscSection s, IS subpointMap, PetscSection *subs)
2132: {
2133:   PetscFunctionBegin;
2134:   PetscCall(PetscSectionCreateSubplexSection_Internal(s, subpointMap, PETSC_FALSE, subs));
2135:   PetscFunctionReturn(PETSC_SUCCESS);
2136: }

2138: static PetscErrorCode PetscSectionView_ASCII(PetscSection s, PetscViewer viewer)
2139: {
2140:   PetscInt    p;
2141:   PetscMPIInt rank;

2143:   PetscFunctionBegin;
2144:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)viewer), &rank));
2145:   PetscCall(PetscViewerASCIIPushSynchronized(viewer));
2146:   PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "Process %d:\n", rank));
2147:   for (p = 0; p < s->pEnd - s->pStart; ++p) {
2148:     if ((s->bc) && (s->bc->atlasDof[p] > 0)) {
2149:       PetscInt b;

2151:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "  (%4" PetscInt_FMT ") dim %2" PetscInt_FMT " offset %3" PetscInt_FMT " constrained", p + s->pStart, s->atlasDof[p], s->atlasOff[p]));
2152:       if (s->bcIndices) {
2153:         for (b = 0; b < s->bc->atlasDof[p]; ++b) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, " %" PetscInt_FMT, s->bcIndices[s->bc->atlasOff[p] + b]));
2154:       }
2155:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "\n"));
2156:     } else {
2157:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "  (%4" PetscInt_FMT ") dim %2" PetscInt_FMT " offset %3" PetscInt_FMT "\n", p + s->pStart, s->atlasDof[p], s->atlasOff[p]));
2158:     }
2159:   }
2160:   PetscCall(PetscViewerFlush(viewer));
2161:   PetscCall(PetscViewerASCIIPopSynchronized(viewer));
2162:   if (s->sym) {
2163:     PetscCall(PetscViewerASCIIPushTab(viewer));
2164:     PetscCall(PetscSectionSymView(s->sym, viewer));
2165:     PetscCall(PetscViewerASCIIPopTab(viewer));
2166:   }
2167:   PetscFunctionReturn(PETSC_SUCCESS);
2168: }

2170: /*@C
2171:    PetscSectionViewFromOptions - View the `PetscSection` based on values in the options database

2173:    Collective

2175:    Input Parameters:
2176: +  A - the PetscSection object to view
2177: .  obj - Optional object that provides the options prefix used for the options
2178: -  name - command line option

2180:    Level: intermediate

2182: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionView`, `PetscObjectViewFromOptions()`, `PetscSectionCreate()`, `PetscSectionView()`
2183: @*/
2184: PetscErrorCode PetscSectionViewFromOptions(PetscSection A, PetscObject obj, const char name[])
2185: {
2186:   PetscFunctionBegin;
2188:   PetscCall(PetscObjectViewFromOptions((PetscObject)A, obj, name));
2189:   PetscFunctionReturn(PETSC_SUCCESS);
2190: }

2192: /*@C
2193:   PetscSectionView - Views a `PetscSection`

2195:   Collective

2197:   Input Parameters:
2198: + s - the `PetscSection` object to view
2199: - v - the viewer

2201:   Level: beginner

2203:   Note:
2204:   `PetscSectionView()`, when viewer is of type `PETSCVIEWERHDF5`, only saves
2205:   distribution independent data, such as dofs, offsets, constraint dofs,
2206:   and constraint indices. Points that have negative dofs, for instance,
2207:   are not saved as they represent points owned by other processes.
2208:   Point numbering and rank assignment is currently not stored.
2209:   The saved section can be loaded with `PetscSectionLoad()`.

2211: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionCreate()`, `PetscSectionDestroy()`, `PetscSectionLoad()`, `PetscViewer`
2212: @*/
2213: PetscErrorCode PetscSectionView(PetscSection s, PetscViewer viewer)
2214: {
2215:   PetscBool isascii, ishdf5;
2216:   PetscInt  f;

2218:   PetscFunctionBegin;
2220:   if (!viewer) PetscCall(PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)s), &viewer));
2222:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &isascii));
2223:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERHDF5, &ishdf5));
2224:   if (isascii) {
2225:     PetscCall(PetscObjectPrintClassNamePrefixType((PetscObject)s, viewer));
2226:     if (s->numFields) {
2227:       PetscCall(PetscViewerASCIIPrintf(viewer, "%" PetscInt_FMT " fields\n", s->numFields));
2228:       for (f = 0; f < s->numFields; ++f) {
2229:         PetscCall(PetscViewerASCIIPrintf(viewer, "  field %" PetscInt_FMT " with %" PetscInt_FMT " components\n", f, s->numFieldComponents[f]));
2230:         PetscCall(PetscSectionView_ASCII(s->field[f], viewer));
2231:       }
2232:     } else {
2233:       PetscCall(PetscSectionView_ASCII(s, viewer));
2234:     }
2235:   } else if (ishdf5) {
2236: #if PetscDefined(HAVE_HDF5)
2237:     PetscCall(PetscSectionView_HDF5_Internal(s, viewer));
2238: #else
2239:     SETERRQ(PetscObjectComm((PetscObject)s), PETSC_ERR_SUP, "HDF5 not supported in this build.\nPlease reconfigure using --download-hdf5");
2240: #endif
2241:   }
2242:   PetscFunctionReturn(PETSC_SUCCESS);
2243: }

2245: /*@C
2246:   PetscSectionLoad - Loads a `PetscSection`

2248:   Collective

2250:   Input Parameters:
2251: + s - the `PetscSection` object to load
2252: - v - the viewer

2254:   Level: beginner

2256:   Note:
2257:   `PetscSectionLoad()`, when viewer is of type `PETSCVIEWERHDF5`, loads
2258:   a section saved with `PetscSectionView()`. The number of processes
2259:   used here (N) does not need to be the same as that used when saving.
2260:   After calling this function, the chart of s on rank i will be set
2261:   to [0, E_i), where \sum_{i=0}^{N-1}E_i equals to the total number of
2262:   saved section points.

2264: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionCreate()`, `PetscSectionDestroy()`, `PetscSectionView()`
2265: @*/
2266: PetscErrorCode PetscSectionLoad(PetscSection s, PetscViewer viewer)
2267: {
2268:   PetscBool ishdf5;

2270:   PetscFunctionBegin;
2273:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERHDF5, &ishdf5));
2274:   if (ishdf5) {
2275: #if PetscDefined(HAVE_HDF5)
2276:     PetscCall(PetscSectionLoad_HDF5_Internal(s, viewer));
2277:     PetscFunctionReturn(PETSC_SUCCESS);
2278: #else
2279:     SETERRQ(PetscObjectComm((PetscObject)s), PETSC_ERR_SUP, "HDF5 not supported in this build.\nPlease reconfigure using --download-hdf5");
2280: #endif
2281:   } else SETERRQ(PetscObjectComm((PetscObject)s), PETSC_ERR_SUP, "Viewer type %s not yet supported for PetscSection loading", ((PetscObject)viewer)->type_name);
2282: }

2284: static PetscErrorCode PetscSectionResetClosurePermutation(PetscSection section)
2285: {
2286:   PetscSectionClosurePermVal clVal;

2288:   PetscFunctionBegin;
2289:   if (!section->clHash) PetscFunctionReturn(PETSC_SUCCESS);
2290:   kh_foreach_value(section->clHash, clVal, {
2291:     PetscCall(PetscFree(clVal.perm));
2292:     PetscCall(PetscFree(clVal.invPerm));
2293:   });
2294:   kh_destroy(ClPerm, section->clHash);
2295:   section->clHash = NULL;
2296:   PetscFunctionReturn(PETSC_SUCCESS);
2297: }

2299: /*@
2300:   PetscSectionReset - Frees all section data.

2302:   Not Collective

2304:   Input Parameters:
2305: . s - the `PetscSection`

2307:   Level: beginner

2309: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionCreate()`
2310: @*/
2311: PetscErrorCode PetscSectionReset(PetscSection s)
2312: {
2313:   PetscInt f, c;

2315:   PetscFunctionBegin;
2317:   for (f = 0; f < s->numFields; ++f) {
2318:     PetscCall(PetscSectionDestroy(&s->field[f]));
2319:     PetscCall(PetscFree(s->fieldNames[f]));
2320:     for (c = 0; c < s->numFieldComponents[f]; ++c) PetscCall(PetscFree(s->compNames[f][c]));
2321:     PetscCall(PetscFree(s->compNames[f]));
2322:   }
2323:   PetscCall(PetscFree(s->numFieldComponents));
2324:   PetscCall(PetscFree(s->fieldNames));
2325:   PetscCall(PetscFree(s->compNames));
2326:   PetscCall(PetscFree(s->field));
2327:   PetscCall(PetscSectionDestroy(&s->bc));
2328:   PetscCall(PetscFree(s->bcIndices));
2329:   PetscCall(PetscFree2(s->atlasDof, s->atlasOff));
2330:   PetscCall(PetscSectionDestroy(&s->clSection));
2331:   PetscCall(ISDestroy(&s->clPoints));
2332:   PetscCall(ISDestroy(&s->perm));
2333:   PetscCall(PetscSectionResetClosurePermutation(s));
2334:   PetscCall(PetscSectionSymDestroy(&s->sym));
2335:   PetscCall(PetscSectionDestroy(&s->clSection));
2336:   PetscCall(ISDestroy(&s->clPoints));
2337:   PetscCall(PetscSectionInvalidateMaxDof_Internal(s));
2338:   s->pStart    = -1;
2339:   s->pEnd      = -1;
2340:   s->maxDof    = 0;
2341:   s->setup     = PETSC_FALSE;
2342:   s->numFields = 0;
2343:   s->clObj     = NULL;
2344:   PetscFunctionReturn(PETSC_SUCCESS);
2345: }

2347: /*@
2348:   PetscSectionDestroy - Frees a section object and frees its range if that exists.

2350:   Not Collective

2352:   Input Parameters:
2353: . s - the `PetscSection`

2355:   Level: beginner

2357: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionCreate()`, `PetscSectionReset()`
2358: @*/
2359: PetscErrorCode PetscSectionDestroy(PetscSection *s)
2360: {
2361:   PetscFunctionBegin;
2362:   if (!*s) PetscFunctionReturn(PETSC_SUCCESS);
2364:   if (--((PetscObject)(*s))->refct > 0) {
2365:     *s = NULL;
2366:     PetscFunctionReturn(PETSC_SUCCESS);
2367:   }
2368:   PetscCall(PetscSectionReset(*s));
2369:   PetscCall(PetscHeaderDestroy(s));
2370:   PetscFunctionReturn(PETSC_SUCCESS);
2371: }

2373: PetscErrorCode VecIntGetValuesSection(PetscInt *baseArray, PetscSection s, PetscInt point, const PetscInt **values)
2374: {
2375:   const PetscInt p = point - s->pStart;

2377:   PetscFunctionBegin;
2379:   *values = &baseArray[s->atlasOff[p]];
2380:   PetscFunctionReturn(PETSC_SUCCESS);
2381: }

2383: PetscErrorCode VecIntSetValuesSection(PetscInt *baseArray, PetscSection s, PetscInt point, const PetscInt values[], InsertMode mode)
2384: {
2385:   PetscInt      *array;
2386:   const PetscInt p           = point - s->pStart;
2387:   const PetscInt orientation = 0; /* Needs to be included for use in closure operations */
2388:   PetscInt       cDim        = 0;

2390:   PetscFunctionBegin;
2392:   PetscCall(PetscSectionGetConstraintDof(s, p, &cDim));
2393:   array = &baseArray[s->atlasOff[p]];
2394:   if (!cDim) {
2395:     if (orientation >= 0) {
2396:       const PetscInt dim = s->atlasDof[p];
2397:       PetscInt       i;

2399:       if (mode == INSERT_VALUES) {
2400:         for (i = 0; i < dim; ++i) array[i] = values[i];
2401:       } else {
2402:         for (i = 0; i < dim; ++i) array[i] += values[i];
2403:       }
2404:     } else {
2405:       PetscInt offset = 0;
2406:       PetscInt j      = -1, field, i;

2408:       for (field = 0; field < s->numFields; ++field) {
2409:         const PetscInt dim = s->field[field]->atlasDof[p];

2411:         for (i = dim - 1; i >= 0; --i) array[++j] = values[i + offset];
2412:         offset += dim;
2413:       }
2414:     }
2415:   } else {
2416:     if (orientation >= 0) {
2417:       const PetscInt  dim  = s->atlasDof[p];
2418:       PetscInt        cInd = 0, i;
2419:       const PetscInt *cDof;

2421:       PetscCall(PetscSectionGetConstraintIndices(s, point, &cDof));
2422:       if (mode == INSERT_VALUES) {
2423:         for (i = 0; i < dim; ++i) {
2424:           if ((cInd < cDim) && (i == cDof[cInd])) {
2425:             ++cInd;
2426:             continue;
2427:           }
2428:           array[i] = values[i];
2429:         }
2430:       } else {
2431:         for (i = 0; i < dim; ++i) {
2432:           if ((cInd < cDim) && (i == cDof[cInd])) {
2433:             ++cInd;
2434:             continue;
2435:           }
2436:           array[i] += values[i];
2437:         }
2438:       }
2439:     } else {
2440:       const PetscInt *cDof;
2441:       PetscInt        offset  = 0;
2442:       PetscInt        cOffset = 0;
2443:       PetscInt        j       = 0, field;

2445:       PetscCall(PetscSectionGetConstraintIndices(s, point, &cDof));
2446:       for (field = 0; field < s->numFields; ++field) {
2447:         const PetscInt dim  = s->field[field]->atlasDof[p];     /* PetscSectionGetFieldDof() */
2448:         const PetscInt tDim = s->field[field]->bc->atlasDof[p]; /* PetscSectionGetFieldConstraintDof() */
2449:         const PetscInt sDim = dim - tDim;
2450:         PetscInt       cInd = 0, i, k;

2452:         for (i = 0, k = dim + offset - 1; i < dim; ++i, ++j, --k) {
2453:           if ((cInd < sDim) && (j == cDof[cInd + cOffset])) {
2454:             ++cInd;
2455:             continue;
2456:           }
2457:           array[j] = values[k];
2458:         }
2459:         offset += dim;
2460:         cOffset += dim - tDim;
2461:       }
2462:     }
2463:   }
2464:   PetscFunctionReturn(PETSC_SUCCESS);
2465: }

2467: /*@C
2468:   PetscSectionHasConstraints - Determine whether a section has constrained dofs

2470:   Not Collective

2472:   Input Parameter:
2473: . s - The `PetscSection`

2475:   Output Parameter:
2476: . hasConstraints - flag indicating that the section has constrained dofs

2478:   Level: intermediate

2480: .seealso: [PetscSection](sec_petscsection), `PetscSectionSetConstraintIndices()`, `PetscSectionGetConstraintDof()`, `PetscSection`
2481: @*/
2482: PetscErrorCode PetscSectionHasConstraints(PetscSection s, PetscBool *hasConstraints)
2483: {
2484:   PetscFunctionBegin;
2487:   *hasConstraints = s->bc ? PETSC_TRUE : PETSC_FALSE;
2488:   PetscFunctionReturn(PETSC_SUCCESS);
2489: }

2491: /*@C
2492:   PetscSectionGetConstraintIndices - Get the point dof numbers, in [0, dof), which are constrained

2494:   Not Collective

2496:   Input Parameters:
2497: + s     - The `PetscSection`
2498: - point - The point

2500:   Output Parameter:
2501: . indices - The constrained dofs

2503:   Level: intermediate

2505:   Fortran Note:
2506:   Call `PetscSectionGetConstraintIndicesF90()` and `PetscSectionRestoreConstraintIndicesF90()`

2508: .seealso: [PetscSection](sec_petscsection), `PetscSectionSetConstraintIndices()`, `PetscSectionGetConstraintDof()`, `PetscSection`
2509: @*/
2510: PetscErrorCode PetscSectionGetConstraintIndices(PetscSection s, PetscInt point, const PetscInt **indices)
2511: {
2512:   PetscFunctionBegin;
2514:   if (s->bc) {
2515:     PetscCall(VecIntGetValuesSection(s->bcIndices, s->bc, point, indices));
2516:   } else *indices = NULL;
2517:   PetscFunctionReturn(PETSC_SUCCESS);
2518: }

2520: /*@C
2521:   PetscSectionSetConstraintIndices - Set the point dof numbers, in [0, dof), which are constrained

2523:   Not Collective

2525:   Input Parameters:
2526: + s     - The `PetscSection`
2527: . point - The point
2528: - indices - The constrained dofs

2530:   Level: intermediate

2532:   Fortran Note:
2533:   Use `PetscSectionSetConstraintIndicesF90()`

2535: .seealso: [PetscSection](sec_petscsection), `PetscSectionGetConstraintIndices()`, `PetscSectionGetConstraintDof()`, `PetscSection`
2536: @*/
2537: PetscErrorCode PetscSectionSetConstraintIndices(PetscSection s, PetscInt point, const PetscInt indices[])
2538: {
2539:   PetscFunctionBegin;
2541:   if (s->bc) {
2542:     const PetscInt dof  = s->atlasDof[point];
2543:     const PetscInt cdof = s->bc->atlasDof[point];
2544:     PetscInt       d;

2546:     for (d = 0; d < cdof; ++d) PetscCheck(indices[d] < dof, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Point %" PetscInt_FMT " dof %" PetscInt_FMT ", invalid constraint index[%" PetscInt_FMT "]: %" PetscInt_FMT, point, dof, d, indices[d]);
2547:     PetscCall(VecIntSetValuesSection(s->bcIndices, s->bc, point, indices, INSERT_VALUES));
2548:   }
2549:   PetscFunctionReturn(PETSC_SUCCESS);
2550: }

2552: /*@C
2553:   PetscSectionGetFieldConstraintIndices - Get the field dof numbers, in [0, fdof), which are constrained

2555:   Not Collective

2557:   Input Parameters:
2558: + s     - The `PetscSection`
2559: . field  - The field number
2560: - point - The point

2562:   Output Parameter:
2563: . indices - The constrained dofs sorted in ascending order

2565:   Level: intermediate

2567:   Note:
2568:   The indices array, which is provided by the caller, must have capacity to hold the number of constrained dofs, e.g., as returned by `PetscSectionGetConstraintDof()`.

2570:   Fortran Note:
2571:   Call `PetscSectionGetFieldConstraintIndicesF90()` and `PetscSectionRestoreFieldConstraintIndicesF90()`

2573: .seealso: [PetscSection](sec_petscsection), `PetscSectionSetFieldConstraintIndices()`, `PetscSectionGetConstraintIndices()`, `PetscSectionGetConstraintDof()`, `PetscSection`
2574: @*/
2575: PetscErrorCode PetscSectionGetFieldConstraintIndices(PetscSection s, PetscInt point, PetscInt field, const PetscInt **indices)
2576: {
2577:   PetscFunctionBegin;
2580:   PetscSectionCheckValidField(field, s->numFields);
2581:   PetscCall(PetscSectionGetConstraintIndices(s->field[field], point, indices));
2582:   PetscFunctionReturn(PETSC_SUCCESS);
2583: }

2585: /*@C
2586:   PetscSectionSetFieldConstraintIndices - Set the field dof numbers, in [0, fdof), which are constrained

2588:   Not Collective

2590:   Input Parameters:
2591: + s       - The `PetscSection`
2592: . point   - The point
2593: . field   - The field number
2594: - indices - The constrained dofs

2596:   Level: intermediate

2598:   Fortran Note:
2599:   Use `PetscSectionSetFieldConstraintIndicesF90()`

2601: .seealso: [PetscSection](sec_petscsection), `PetscSectionSetConstraintIndices()`, `PetscSectionGetFieldConstraintIndices()`, `PetscSectionGetConstraintDof()`, `PetscSection`
2602: @*/
2603: PetscErrorCode PetscSectionSetFieldConstraintIndices(PetscSection s, PetscInt point, PetscInt field, const PetscInt indices[])
2604: {
2605:   PetscFunctionBegin;
2607:   if (PetscDefined(USE_DEBUG)) {
2608:     PetscInt nfdof;

2610:     PetscCall(PetscSectionGetFieldConstraintDof(s, point, field, &nfdof));
2612:   }
2613:   PetscSectionCheckValidField(field, s->numFields);
2614:   PetscCall(PetscSectionSetConstraintIndices(s->field[field], point, indices));
2615:   PetscFunctionReturn(PETSC_SUCCESS);
2616: }

2618: /*@
2619:   PetscSectionPermute - Reorder the section according to the input point permutation

2621:   Collective

2623:   Input Parameters:
2624: + section - The `PetscSection` object
2625: - perm - The point permutation, old point p becomes new point perm[p]

2627:   Output Parameter:
2628: . sectionNew - The permuted `PetscSection`

2630:   Level: intermediate

2632: .seealso: [PetscSection](sec_petscsection), `IS`, `PetscSection`, `MatPermute()`
2633: @*/
2634: PetscErrorCode PetscSectionPermute(PetscSection section, IS permutation, PetscSection *sectionNew)
2635: {
2636:   PetscSection    s = section, sNew;
2637:   const PetscInt *perm;
2638:   PetscInt        numFields, f, c, numPoints, pStart, pEnd, p;

2640:   PetscFunctionBegin;
2644:   PetscCall(PetscSectionCreate(PetscObjectComm((PetscObject)s), &sNew));
2645:   PetscCall(PetscSectionGetNumFields(s, &numFields));
2646:   if (numFields) PetscCall(PetscSectionSetNumFields(sNew, numFields));
2647:   for (f = 0; f < numFields; ++f) {
2648:     const char *name;
2649:     PetscInt    numComp;

2651:     PetscCall(PetscSectionGetFieldName(s, f, &name));
2652:     PetscCall(PetscSectionSetFieldName(sNew, f, name));
2653:     PetscCall(PetscSectionGetFieldComponents(s, f, &numComp));
2654:     PetscCall(PetscSectionSetFieldComponents(sNew, f, numComp));
2655:     for (c = 0; c < s->numFieldComponents[f]; ++c) {
2656:       PetscCall(PetscSectionGetComponentName(s, f, c, &name));
2657:       PetscCall(PetscSectionSetComponentName(sNew, f, c, name));
2658:     }
2659:   }
2660:   PetscCall(ISGetLocalSize(permutation, &numPoints));
2661:   PetscCall(ISGetIndices(permutation, &perm));
2662:   PetscCall(PetscSectionGetChart(s, &pStart, &pEnd));
2663:   PetscCall(PetscSectionSetChart(sNew, pStart, pEnd));
2664:   PetscCheck(numPoints >= pEnd, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Permutation size %" PetscInt_FMT " is less than largest Section point %" PetscInt_FMT, numPoints, pEnd);
2665:   for (p = pStart; p < pEnd; ++p) {
2666:     PetscInt dof, cdof;

2668:     PetscCall(PetscSectionGetDof(s, p, &dof));
2669:     PetscCall(PetscSectionSetDof(sNew, perm[p], dof));
2670:     PetscCall(PetscSectionGetConstraintDof(s, p, &cdof));
2671:     if (cdof) PetscCall(PetscSectionSetConstraintDof(sNew, perm[p], cdof));
2672:     for (f = 0; f < numFields; ++f) {
2673:       PetscCall(PetscSectionGetFieldDof(s, p, f, &dof));
2674:       PetscCall(PetscSectionSetFieldDof(sNew, perm[p], f, dof));
2675:       PetscCall(PetscSectionGetFieldConstraintDof(s, p, f, &cdof));
2676:       if (cdof) PetscCall(PetscSectionSetFieldConstraintDof(sNew, perm[p], f, cdof));
2677:     }
2678:   }
2679:   PetscCall(PetscSectionSetUp(sNew));
2680:   for (p = pStart; p < pEnd; ++p) {
2681:     const PetscInt *cind;
2682:     PetscInt        cdof;

2684:     PetscCall(PetscSectionGetConstraintDof(s, p, &cdof));
2685:     if (cdof) {
2686:       PetscCall(PetscSectionGetConstraintIndices(s, p, &cind));
2687:       PetscCall(PetscSectionSetConstraintIndices(sNew, perm[p], cind));
2688:     }
2689:     for (f = 0; f < numFields; ++f) {
2690:       PetscCall(PetscSectionGetFieldConstraintDof(s, p, f, &cdof));
2691:       if (cdof) {
2692:         PetscCall(PetscSectionGetFieldConstraintIndices(s, p, f, &cind));
2693:         PetscCall(PetscSectionSetFieldConstraintIndices(sNew, perm[p], f, cind));
2694:       }
2695:     }
2696:   }
2697:   PetscCall(ISRestoreIndices(permutation, &perm));
2698:   *sectionNew = sNew;
2699:   PetscFunctionReturn(PETSC_SUCCESS);
2700: }

2702: /*@
2703:   PetscSectionSetClosureIndex - Set a cache of points in the closure of each point in the section

2705:   Collective

2707:   Input Parameters:
2708: + section   - The `PetscSection`
2709: . obj       - A `PetscObject` which serves as the key for this index
2710: . clSection - `PetscSection` giving the size of the closure of each point
2711: - clPoints  - `IS` giving the points in each closure

2713:   Level: advanced

2715:   Note:
2716:   We compress out closure points with no dofs in this section

2718: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionGetClosureIndex()`, `DMPlexCreateClosureIndex()`
2719: @*/
2720: PetscErrorCode PetscSectionSetClosureIndex(PetscSection section, PetscObject obj, PetscSection clSection, IS clPoints)
2721: {
2722:   PetscFunctionBegin;
2726:   if (section->clObj != obj) PetscCall(PetscSectionResetClosurePermutation(section));
2727:   section->clObj = obj;
2728:   PetscCall(PetscObjectReference((PetscObject)clSection));
2729:   PetscCall(PetscObjectReference((PetscObject)clPoints));
2730:   PetscCall(PetscSectionDestroy(&section->clSection));
2731:   PetscCall(ISDestroy(&section->clPoints));
2732:   section->clSection = clSection;
2733:   section->clPoints  = clPoints;
2734:   PetscFunctionReturn(PETSC_SUCCESS);
2735: }

2737: /*@
2738:   PetscSectionGetClosureIndex - Get the cache of points in the closure of each point in the section set with `PetscSectionSetClosureIndex()`

2740:   Collective

2742:   Input Parameters:
2743: + section   - The `PetscSection`
2744: - obj       - A `PetscObject` which serves as the key for this index

2746:   Output Parameters:
2747: + clSection - `PetscSection` giving the size of the closure of each point
2748: - clPoints  - `IS` giving the points in each closure

2750:   Level: advanced

2752: .seealso: [PetscSection](sec_petscsection), `PetscSectionSetClosureIndex()`, `DMPlexCreateClosureIndex()`
2753: @*/
2754: PetscErrorCode PetscSectionGetClosureIndex(PetscSection section, PetscObject obj, PetscSection *clSection, IS *clPoints)
2755: {
2756:   PetscFunctionBegin;
2757:   if (section->clObj == obj) {
2758:     if (clSection) *clSection = section->clSection;
2759:     if (clPoints) *clPoints = section->clPoints;
2760:   } else {
2761:     if (clSection) *clSection = NULL;
2762:     if (clPoints) *clPoints = NULL;
2763:   }
2764:   PetscFunctionReturn(PETSC_SUCCESS);
2765: }

2767: PetscErrorCode PetscSectionSetClosurePermutation_Internal(PetscSection section, PetscObject obj, PetscInt depth, PetscInt clSize, PetscCopyMode mode, PetscInt *clPerm)
2768: {
2769:   PetscInt                    i;
2770:   khiter_t                    iter;
2771:   int                         new_entry;
2772:   PetscSectionClosurePermKey  key = {depth, clSize};
2773:   PetscSectionClosurePermVal *val;

2775:   PetscFunctionBegin;
2776:   if (section->clObj != obj) {
2777:     PetscCall(PetscSectionDestroy(&section->clSection));
2778:     PetscCall(ISDestroy(&section->clPoints));
2779:   }
2780:   section->clObj = obj;
2781:   if (!section->clHash) PetscCall(PetscClPermCreate(&section->clHash));
2782:   iter = kh_put(ClPerm, section->clHash, key, &new_entry);
2783:   val  = &kh_val(section->clHash, iter);
2784:   if (!new_entry) {
2785:     PetscCall(PetscFree(val->perm));
2786:     PetscCall(PetscFree(val->invPerm));
2787:   }
2788:   if (mode == PETSC_COPY_VALUES) {
2789:     PetscCall(PetscMalloc1(clSize, &val->perm));
2790:     PetscCall(PetscArraycpy(val->perm, clPerm, clSize));
2791:   } else if (mode == PETSC_OWN_POINTER) {
2792:     val->perm = clPerm;
2793:   } else SETERRQ(PetscObjectComm(obj), PETSC_ERR_SUP, "Do not support borrowed arrays");
2794:   PetscCall(PetscMalloc1(clSize, &val->invPerm));
2795:   for (i = 0; i < clSize; ++i) val->invPerm[clPerm[i]] = i;
2796:   PetscFunctionReturn(PETSC_SUCCESS);
2797: }

2799: /*@
2800:   PetscSectionSetClosurePermutation - Set the dof permutation for the closure of each cell in the section, meaning clPerm[newIndex] = oldIndex.

2802:   Not Collective

2804:   Input Parameters:
2805: + section - The `PetscSection`
2806: . obj     - A `PetscObject` which serves as the key for this index (usually a `DM`)
2807: . depth   - Depth of points on which to apply the given permutation
2808: - perm    - Permutation of the cell dof closure

2810:   Level: intermediate

2812:   Notes:
2813:   The specified permutation will only be applied to points at depth whose closure size matches the length of perm.  In a
2814:   mixed-topology or variable-degree finite element space, this function can be called multiple times at each depth for
2815:   each topology and degree.

2817:   This approach assumes that (depth, len(perm)) uniquely identifies the desired permutation; this might not be true for
2818:   exotic/enriched spaces on mixed topology meshes.

2820: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `IS`, `PetscSectionGetClosurePermutation()`, `PetscSectionGetClosureIndex()`, `DMPlexCreateClosureIndex()`, `PetscCopyMode`
2821: @*/
2822: PetscErrorCode PetscSectionSetClosurePermutation(PetscSection section, PetscObject obj, PetscInt depth, IS perm)
2823: {
2824:   const PetscInt *clPerm = NULL;
2825:   PetscInt        clSize = 0;

2827:   PetscFunctionBegin;
2828:   if (perm) {
2829:     PetscCall(ISGetLocalSize(perm, &clSize));
2830:     PetscCall(ISGetIndices(perm, &clPerm));
2831:   }
2832:   PetscCall(PetscSectionSetClosurePermutation_Internal(section, obj, depth, clSize, PETSC_COPY_VALUES, (PetscInt *)clPerm));
2833:   if (perm) PetscCall(ISRestoreIndices(perm, &clPerm));
2834:   PetscFunctionReturn(PETSC_SUCCESS);
2835: }

2837: PetscErrorCode PetscSectionGetClosurePermutation_Internal(PetscSection section, PetscObject obj, PetscInt depth, PetscInt size, const PetscInt *perm[])
2838: {
2839:   PetscFunctionBegin;
2840:   if (section->clObj == obj) {
2841:     PetscSectionClosurePermKey k = {depth, size};
2842:     PetscSectionClosurePermVal v;
2843:     PetscCall(PetscClPermGet(section->clHash, k, &v));
2844:     if (perm) *perm = v.perm;
2845:   } else {
2846:     if (perm) *perm = NULL;
2847:   }
2848:   PetscFunctionReturn(PETSC_SUCCESS);
2849: }

2851: /*@
2852:   PetscSectionGetClosurePermutation - Get the dof permutation for the closure of each cell in the section, meaning clPerm[newIndex] = oldIndex.

2854:   Not Collective

2856:   Input Parameters:
2857: + section   - The `PetscSection`
2858: . obj       - A `PetscObject` which serves as the key for this index (usually a DM)
2859: . depth     - Depth stratum on which to obtain closure permutation
2860: - clSize    - Closure size to be permuted (e.g., may vary with element topology and degree)

2862:   Output Parameter:
2863: . perm - The dof closure permutation

2865:   Level: intermediate

2867:   Note:
2868:   The user must destroy the `IS` that is returned.

2870: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `IS`, `PetscSectionSetClosurePermutation()`, `PetscSectionGetClosureInversePermutation()`, `PetscSectionGetClosureIndex()`, `PetscSectionSetClosureIndex()`, `DMPlexCreateClosureIndex()`
2871: @*/
2872: PetscErrorCode PetscSectionGetClosurePermutation(PetscSection section, PetscObject obj, PetscInt depth, PetscInt clSize, IS *perm)
2873: {
2874:   const PetscInt *clPerm;

2876:   PetscFunctionBegin;
2877:   PetscCall(PetscSectionGetClosurePermutation_Internal(section, obj, depth, clSize, &clPerm));
2878:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, clSize, clPerm, PETSC_USE_POINTER, perm));
2879:   PetscFunctionReturn(PETSC_SUCCESS);
2880: }

2882: PetscErrorCode PetscSectionGetClosureInversePermutation_Internal(PetscSection section, PetscObject obj, PetscInt depth, PetscInt size, const PetscInt *perm[])
2883: {
2884:   PetscFunctionBegin;
2885:   if (section->clObj == obj && section->clHash) {
2886:     PetscSectionClosurePermKey k = {depth, size};
2887:     PetscSectionClosurePermVal v;
2888:     PetscCall(PetscClPermGet(section->clHash, k, &v));
2889:     if (perm) *perm = v.invPerm;
2890:   } else {
2891:     if (perm) *perm = NULL;
2892:   }
2893:   PetscFunctionReturn(PETSC_SUCCESS);
2894: }

2896: /*@
2897:   PetscSectionGetClosureInversePermutation - Get the inverse dof permutation for the closure of each cell in the section, meaning clPerm[oldIndex] = newIndex.

2899:   Not Collective

2901:   Input Parameters:
2902: + section   - The `PetscSection`
2903: . obj       - A `PetscObject` which serves as the key for this index (usually a `DM`)
2904: . depth     - Depth stratum on which to obtain closure permutation
2905: - clSize    - Closure size to be permuted (e.g., may vary with element topology and degree)

2907:   Output Parameters:
2908: . perm - The dof closure permutation

2910:   Level: intermediate

2912:   Note:
2913:   The user must destroy the `IS` that is returned.

2915: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `IS`, `PetscSectionSetClosurePermutation()`, `PetscSectionGetClosureIndex()`, `PetscSectionSetClosureIndex()`, `DMPlexCreateClosureIndex()`
2916: @*/
2917: PetscErrorCode PetscSectionGetClosureInversePermutation(PetscSection section, PetscObject obj, PetscInt depth, PetscInt clSize, IS *perm)
2918: {
2919:   const PetscInt *clPerm;

2921:   PetscFunctionBegin;
2922:   PetscCall(PetscSectionGetClosureInversePermutation_Internal(section, obj, depth, clSize, &clPerm));
2923:   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, clSize, clPerm, PETSC_USE_POINTER, perm));
2924:   PetscFunctionReturn(PETSC_SUCCESS);
2925: }

2927: /*@
2928:   PetscSectionGetField - Get the subsection associated with a single field

2930:   Input Parameters:
2931: + s     - The `PetscSection`
2932: - field - The field number

2934:   Output Parameter:
2935: . subs  - The subsection for the given field

2937:   Level: intermediate

2939:   Note:
2940:   Does not increase the reference count of the selected sub-section. There is no matching `PetscSectionRestoreField()`

2942: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `IS`, `PetscSectionSetNumFields()`
2943: @*/
2944: PetscErrorCode PetscSectionGetField(PetscSection s, PetscInt field, PetscSection *subs)
2945: {
2946:   PetscFunctionBegin;
2949:   PetscSectionCheckValidField(field, s->numFields);
2950:   *subs = s->field[field];
2951:   PetscFunctionReturn(PETSC_SUCCESS);
2952: }

2954: PetscClassId      PETSC_SECTION_SYM_CLASSID;
2955: PetscFunctionList PetscSectionSymList = NULL;

2957: /*@
2958:   PetscSectionSymCreate - Creates an empty `PetscSectionSym` object.

2960:   Collective

2962:   Input Parameter:
2963: . comm - the MPI communicator

2965:   Output Parameter:
2966: . sym - pointer to the new set of symmetries

2968:   Level: developer

2970: .seealso: [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionSym`, `PetscSectionSymDestroy()`
2971: @*/
2972: PetscErrorCode PetscSectionSymCreate(MPI_Comm comm, PetscSectionSym *sym)
2973: {
2974:   PetscFunctionBegin;
2976:   PetscCall(ISInitializePackage());
2977:   PetscCall(PetscHeaderCreate(*sym, PETSC_SECTION_SYM_CLASSID, "PetscSectionSym", "Section Symmetry", "IS", comm, PetscSectionSymDestroy, PetscSectionSymView));
2978:   PetscFunctionReturn(PETSC_SUCCESS);
2979: }

2981: /*@C
2982:   PetscSectionSymSetType - Builds a `PetscSectionSym`, for a particular implementation.

2984:   Collective

2986:   Input Parameters:
2987: + sym    - The section symmetry object
2988: - method - The name of the section symmetry type

2990:   Level: developer

2992: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionSymType`, `PetscSectionSymGetType()`, `PetscSectionSymCreate()`
2993: @*/
2994: PetscErrorCode PetscSectionSymSetType(PetscSectionSym sym, PetscSectionSymType method)
2995: {
2996:   PetscErrorCode (*r)(PetscSectionSym);
2997:   PetscBool match;

2999:   PetscFunctionBegin;
3001:   PetscCall(PetscObjectTypeCompare((PetscObject)sym, method, &match));
3002:   if (match) PetscFunctionReturn(PETSC_SUCCESS);

3004:   PetscCall(PetscFunctionListFind(PetscSectionSymList, method, &r));
3005:   PetscCheck(r, PETSC_COMM_SELF, PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown PetscSectionSym type: %s", method);
3006:   PetscTryTypeMethod(sym, destroy);
3007:   sym->ops->destroy = NULL;

3009:   PetscCall((*r)(sym));
3010:   PetscCall(PetscObjectChangeTypeName((PetscObject)sym, method));
3011:   PetscFunctionReturn(PETSC_SUCCESS);
3012: }

3014: /*@C
3015:   PetscSectionSymGetType - Gets the section symmetry type name (as a string) from the `PetscSectionSym`.

3017:   Not Collective

3019:   Input Parameter:
3020: . sym  - The section symmetry

3022:   Output Parameter:
3023: . type - The index set type name

3025:   Level: developer

3027: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionSymType`, `PetscSectionSymSetType()`, `PetscSectionSymCreate()`
3028: @*/
3029: PetscErrorCode PetscSectionSymGetType(PetscSectionSym sym, PetscSectionSymType *type)
3030: {
3031:   PetscFunctionBegin;
3034:   *type = ((PetscObject)sym)->type_name;
3035:   PetscFunctionReturn(PETSC_SUCCESS);
3036: }

3038: /*@C
3039:   PetscSectionSymRegister - Registers a new section symmetry implementation

3041:   Not Collective

3043:   Input Parameters:
3044: + name        - The name of a new user-defined creation routine
3045: - create_func - The creation routine itself

3047:   Level: developer

3049:   Notes:
3050:   `PetscSectionSymRegister()` may be called multiple times to add several user-defined vectors

3052: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionSymType`, `PetscSectionSymCreate()`, `PetscSectionSymSetType()`
3053: @*/
3054: PetscErrorCode PetscSectionSymRegister(const char sname[], PetscErrorCode (*function)(PetscSectionSym))
3055: {
3056:   PetscFunctionBegin;
3057:   PetscCall(ISInitializePackage());
3058:   PetscCall(PetscFunctionListAdd(&PetscSectionSymList, sname, function));
3059:   PetscFunctionReturn(PETSC_SUCCESS);
3060: }

3062: /*@
3063:    PetscSectionSymDestroy - Destroys a section symmetry.

3065:    Collective

3067:    Input Parameters:
3068: .  sym - the section symmetry

3070:    Level: developer

3072: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionSymCreate()`, `PetscSectionSymDestroy()`
3073: @*/
3074: PetscErrorCode PetscSectionSymDestroy(PetscSectionSym *sym)
3075: {
3076:   SymWorkLink link, next;

3078:   PetscFunctionBegin;
3079:   if (!*sym) PetscFunctionReturn(PETSC_SUCCESS);
3081:   if (--((PetscObject)(*sym))->refct > 0) {
3082:     *sym = NULL;
3083:     PetscFunctionReturn(PETSC_SUCCESS);
3084:   }
3085:   if ((*sym)->ops->destroy) PetscCall((*(*sym)->ops->destroy)(*sym));
3086:   PetscCheck(!(*sym)->workout, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Work array still checked out");
3087:   for (link = (*sym)->workin; link; link = next) {
3088:     PetscInt    **perms = (PetscInt **)link->perms;
3089:     PetscScalar **rots  = (PetscScalar **)link->rots;
3090:     PetscCall(PetscFree2(perms, rots));
3091:     next = link->next;
3092:     PetscCall(PetscFree(link));
3093:   }
3094:   (*sym)->workin = NULL;
3095:   PetscCall(PetscHeaderDestroy(sym));
3096:   PetscFunctionReturn(PETSC_SUCCESS);
3097: }

3099: /*@C
3100:    PetscSectionSymView - Displays a section symmetry

3102:    Collective

3104:    Input Parameters:
3105: +  sym - the index set
3106: -  viewer - viewer used to display the set, for example `PETSC_VIEWER_STDOUT_SELF`.

3108:    Level: developer

3110: .seealso:  `PetscSectionSym`, `PetscViewer`, `PetscViewerASCIIOpen()`
3111: @*/
3112: PetscErrorCode PetscSectionSymView(PetscSectionSym sym, PetscViewer viewer)
3113: {
3114:   PetscFunctionBegin;
3116:   if (!viewer) PetscCall(PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)sym), &viewer));
3118:   PetscCheckSameComm(sym, 1, viewer, 2);
3119:   PetscCall(PetscObjectPrintClassNamePrefixType((PetscObject)sym, viewer));
3120:   PetscTryTypeMethod(sym, view, viewer);
3121:   PetscFunctionReturn(PETSC_SUCCESS);
3122: }

3124: /*@
3125:   PetscSectionSetSym - Set the symmetries for the data referred to by the section

3127:   Collective

3129:   Input Parameters:
3130: + section - the section describing data layout
3131: - sym - the symmetry describing the affect of orientation on the access of the data

3133:   Level: developer

3135: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionGetSym()`, `PetscSectionSymCreate()`
3136: @*/
3137: PetscErrorCode PetscSectionSetSym(PetscSection section, PetscSectionSym sym)
3138: {
3139:   PetscFunctionBegin;
3141:   PetscCall(PetscSectionSymDestroy(&(section->sym)));
3142:   if (sym) {
3144:     PetscCheckSameComm(section, 1, sym, 2);
3145:     PetscCall(PetscObjectReference((PetscObject)sym));
3146:   }
3147:   section->sym = sym;
3148:   PetscFunctionReturn(PETSC_SUCCESS);
3149: }

3151: /*@
3152:   PetscSectionGetSym - Get the symmetries for the data referred to by the section

3154:   Not Collective

3156:   Input Parameters:
3157: . section - the section describing data layout

3159:   Output Parameters:
3160: . sym - the symmetry describing the affect of orientation on the access of the data

3162:   Level: developer

3164: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionSetSym()`, `PetscSectionSymCreate()`
3165: @*/
3166: PetscErrorCode PetscSectionGetSym(PetscSection section, PetscSectionSym *sym)
3167: {
3168:   PetscFunctionBegin;
3170:   *sym = section->sym;
3171:   PetscFunctionReturn(PETSC_SUCCESS);
3172: }

3174: /*@
3175:   PetscSectionSetFieldSym - Set the symmetries for the data referred to by a field of the section

3177:   Collective

3179:   Input Parameters:
3180: + section - the section describing data layout
3181: . field - the field number
3182: - sym - the symmetry describing the affect of orientation on the access of the data

3184:   Level: developer

3186: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionGetFieldSym()`, `PetscSectionSymCreate()`
3187: @*/
3188: PetscErrorCode PetscSectionSetFieldSym(PetscSection section, PetscInt field, PetscSectionSym sym)
3189: {
3190:   PetscFunctionBegin;
3192:   PetscSectionCheckValidField(field, section->numFields);
3193:   PetscCall(PetscSectionSetSym(section->field[field], sym));
3194:   PetscFunctionReturn(PETSC_SUCCESS);
3195: }

3197: /*@
3198:   PetscSectionGetFieldSym - Get the symmetries for the data referred to by a field of the section

3200:   Collective

3202:   Input Parameters:
3203: + section - the section describing data layout
3204: - field - the field number

3206:   Output Parameters:
3207: . sym - the symmetry describing the affect of orientation on the access of the data

3209:   Level: developer

3211: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionSetFieldSym()`, `PetscSectionSymCreate()`
3212: @*/
3213: PetscErrorCode PetscSectionGetFieldSym(PetscSection section, PetscInt field, PetscSectionSym *sym)
3214: {
3215:   PetscFunctionBegin;
3217:   PetscSectionCheckValidField(field, section->numFields);
3218:   *sym = section->field[field]->sym;
3219:   PetscFunctionReturn(PETSC_SUCCESS);
3220: }

3222: /*@C
3223:   PetscSectionGetPointSyms - Get the symmetries for a set of points in a `PetscSection` under specific orientations.

3225:   Not Collective

3227:   Input Parameters:
3228: + section - the section
3229: . numPoints - the number of points
3230: - points - an array of size 2 * numPoints, containing a list of (point, orientation) pairs. (An orientation is an
3231:     arbitrary integer: its interpretation is up to sym.  Orientations are used by DM: for their interpretation in that
3232:     context, see DMPlexGetConeOrientation()).

3234:   Output Parameters:
3235: + perms - The permutations for the given orientations (or NULL if there is no symmetry or the permutation is the identity).
3236: - rots - The field rotations symmetries for the given orientations (or NULL if there is no symmetry or the rotations are all
3237:     identity).

3239:   Example of usage, gathering dofs into a local array (lArray) from a section array (sArray):
3240: .vb
3241:      const PetscInt    **perms;
3242:      const PetscScalar **rots;
3243:      PetscInt            lOffset;

3245:      PetscSectionGetPointSyms(section,numPoints,points,&perms,&rots);
3246:      for (i = 0, lOffset = 0; i < numPoints; i++) {
3247:        PetscInt           point = points[2*i], dof, sOffset;
3248:        const PetscInt    *perm  = perms ? perms[i] : NULL;
3249:        const PetscScalar *rot   = rots  ? rots[i]  : NULL;

3251:        PetscSectionGetDof(section,point,&dof);
3252:        PetscSectionGetOffset(section,point,&sOffset);

3254:        if (perm) {for (j = 0; j < dof; j++) {lArray[lOffset + perm[j]]  = sArray[sOffset + j];}}
3255:        else      {for (j = 0; j < dof; j++) {lArray[lOffset +      j ]  = sArray[sOffset + j];}}
3256:        if (rot)  {for (j = 0; j < dof; j++) {lArray[lOffset +      j ] *= rot[j];             }}
3257:        lOffset += dof;
3258:      }
3259:      PetscSectionRestorePointSyms(section,numPoints,points,&perms,&rots);
3260: .ve

3262:   Example of usage, adding dofs into a section array (sArray) from a local array (lArray):
3263: .vb
3264:      const PetscInt    **perms;
3265:      const PetscScalar **rots;
3266:      PetscInt            lOffset;

3268:      PetscSectionGetPointSyms(section,numPoints,points,&perms,&rots);
3269:      for (i = 0, lOffset = 0; i < numPoints; i++) {
3270:        PetscInt           point = points[2*i], dof, sOffset;
3271:        const PetscInt    *perm  = perms ? perms[i] : NULL;
3272:        const PetscScalar *rot   = rots  ? rots[i]  : NULL;

3274:        PetscSectionGetDof(section,point,&dof);
3275:        PetscSectionGetOffset(section,point,&sOff);

3277:        if (perm) {for (j = 0; j < dof; j++) {sArray[sOffset + j] += lArray[lOffset + perm[j]] * (rot ? PetscConj(rot[perm[j]]) : 1.);}}
3278:        else      {for (j = 0; j < dof; j++) {sArray[sOffset + j] += lArray[lOffset +      j ] * (rot ? PetscConj(rot[     j ]) : 1.);}}
3279:        offset += dof;
3280:      }
3281:      PetscSectionRestorePointSyms(section,numPoints,points,&perms,&rots);
3282: .ve

3284:   Level: developer

3286: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionRestorePointSyms()`, `PetscSectionSymCreate()`, `PetscSectionSetSym()`, `PetscSectionGetSym()`
3287: @*/
3288: PetscErrorCode PetscSectionGetPointSyms(PetscSection section, PetscInt numPoints, const PetscInt *points, const PetscInt ***perms, const PetscScalar ***rots)
3289: {
3290:   PetscSectionSym sym;

3292:   PetscFunctionBegin;
3295:   if (perms) *perms = NULL;
3296:   if (rots) *rots = NULL;
3297:   sym = section->sym;
3298:   if (sym && (perms || rots)) {
3299:     SymWorkLink link;

3301:     if (sym->workin) {
3302:       link        = sym->workin;
3303:       sym->workin = sym->workin->next;
3304:     } else {
3305:       PetscCall(PetscNew(&link));
3306:     }
3307:     if (numPoints > link->numPoints) {
3308:       PetscInt    **perms = (PetscInt **)link->perms;
3309:       PetscScalar **rots  = (PetscScalar **)link->rots;
3310:       PetscCall(PetscFree2(perms, rots));
3311:       PetscCall(PetscMalloc2(numPoints, (PetscInt ***)&link->perms, numPoints, (PetscScalar ***)&link->rots));
3312:       link->numPoints = numPoints;
3313:     }
3314:     link->next   = sym->workout;
3315:     sym->workout = link;
3316:     PetscCall(PetscArrayzero((PetscInt **)link->perms, numPoints));
3317:     PetscCall(PetscArrayzero((PetscInt **)link->rots, numPoints));
3318:     PetscCall((*sym->ops->getpoints)(sym, section, numPoints, points, link->perms, link->rots));
3319:     if (perms) *perms = link->perms;
3320:     if (rots) *rots = link->rots;
3321:   }
3322:   PetscFunctionReturn(PETSC_SUCCESS);
3323: }

3325: /*@C
3326:   PetscSectionRestorePointSyms - Restore the symmetries returned by `PetscSectionGetPointSyms()`

3328:   Not Collective

3330:   Input Parameters:
3331: + section - the section
3332: . numPoints - the number of points
3333: - points - an array of size 2 * numPoints, containing a list of (point, orientation) pairs. (An orientation is an
3334:     arbitrary integer: its interpretation is up to sym.  Orientations are used by `DM`: for their interpretation in that
3335:     context, see `DMPlexGetConeOrientation()`).

3337:   Output Parameters:
3338: + perms - The permutations for the given orientations: set to NULL at conclusion
3339: - rots - The field rotations symmetries for the given orientations: set to NULL at conclusion

3341:   Level: developer

3343: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionGetPointSyms()`, `PetscSectionSymCreate()`, `PetscSectionSetSym()`, `PetscSectionGetSym()`
3344: @*/
3345: PetscErrorCode PetscSectionRestorePointSyms(PetscSection section, PetscInt numPoints, const PetscInt *points, const PetscInt ***perms, const PetscScalar ***rots)
3346: {
3347:   PetscSectionSym sym;

3349:   PetscFunctionBegin;
3351:   sym = section->sym;
3352:   if (sym && (perms || rots)) {
3353:     SymWorkLink *p, link;

3355:     for (p = &sym->workout; (link = *p); p = &link->next) {
3356:       if ((perms && link->perms == *perms) || (rots && link->rots == *rots)) {
3357:         *p          = link->next;
3358:         link->next  = sym->workin;
3359:         sym->workin = link;
3360:         if (perms) *perms = NULL;
3361:         if (rots) *rots = NULL;
3362:         PetscFunctionReturn(PETSC_SUCCESS);
3363:       }
3364:     }
3365:     SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Array was not checked out");
3366:   }
3367:   PetscFunctionReturn(PETSC_SUCCESS);
3368: }

3370: /*@C
3371:   PetscSectionGetFieldPointSyms - Get the symmetries for a set of points in a field of a `PetscSection` under specific orientations.

3373:   Not Collective

3375:   Input Parameters:
3376: + section - the section
3377: . field - the field of the section
3378: . numPoints - the number of points
3379: - points - an array of size 2 * numPoints, containing a list of (point, orientation) pairs. (An orientation is an
3380:     arbitrary integer: its interpretation is up to sym.  Orientations are used by `DM`: for their interpretation in that
3381:     context, see `DMPlexGetConeOrientation()`).

3383:   Output Parameters:
3384: + perms - The permutations for the given orientations (or NULL if there is no symmetry or the permutation is the identity).
3385: - rots - The field rotations symmetries for the given orientations (or NULL if there is no symmetry or the rotations are all
3386:     identity).

3388:   Level: developer

3390: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionGetPointSyms()`, `PetscSectionRestoreFieldPointSyms()`
3391: @*/
3392: PetscErrorCode PetscSectionGetFieldPointSyms(PetscSection section, PetscInt field, PetscInt numPoints, const PetscInt *points, const PetscInt ***perms, const PetscScalar ***rots)
3393: {
3394:   PetscFunctionBegin;
3396:   PetscCheck(field <= section->numFields, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "field %" PetscInt_FMT " greater than number of fields (%" PetscInt_FMT ") in section", field, section->numFields);
3397:   PetscCall(PetscSectionGetPointSyms(section->field[field], numPoints, points, perms, rots));
3398:   PetscFunctionReturn(PETSC_SUCCESS);
3399: }

3401: /*@C
3402:   PetscSectionRestoreFieldPointSyms - Restore the symmetries returned by `PetscSectionGetFieldPointSyms()`

3404:   Not Collective

3406:   Input Parameters:
3407: + section - the section
3408: . field - the field number
3409: . numPoints - the number of points
3410: - points - an array of size 2 * numPoints, containing a list of (point, orientation) pairs. (An orientation is an
3411:     arbitrary integer: its interpretation is up to sym.  Orientations are used by `DM`: for their interpretation in that
3412:     context, see `DMPlexGetConeOrientation()`).

3414:   Output Parameters:
3415: + perms - The permutations for the given orientations: set to NULL at conclusion
3416: - rots - The field rotations symmetries for the given orientations: set to NULL at conclusion

3418:   Level: developer

3420: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionRestorePointSyms()`, `petscSectionGetFieldPointSyms()`, `PetscSectionSymCreate()`, `PetscSectionSetSym()`, `PetscSectionGetSym()`
3421: @*/
3422: PetscErrorCode PetscSectionRestoreFieldPointSyms(PetscSection section, PetscInt field, PetscInt numPoints, const PetscInt *points, const PetscInt ***perms, const PetscScalar ***rots)
3423: {
3424:   PetscFunctionBegin;
3426:   PetscCheck(field <= section->numFields, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "field %" PetscInt_FMT " greater than number of fields (%" PetscInt_FMT ") in section", field, section->numFields);
3427:   PetscCall(PetscSectionRestorePointSyms(section->field[field], numPoints, points, perms, rots));
3428:   PetscFunctionReturn(PETSC_SUCCESS);
3429: }

3431: /*@
3432:   PetscSectionSymCopy - Copy the symmetries, assuming that the point structure is compatible

3434:   Not Collective

3436:   Input Parameter:
3437: . sym - the `PetscSectionSym`

3439:   Output Parameter:
3440: . nsym - the equivalent symmetries

3442:   Level: developer

3444: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionSymCreate()`, `PetscSectionSetSym()`, `PetscSectionGetSym()`, `PetscSectionSymLabelSetStratum()`, `PetscSectionGetPointSyms()`
3445: @*/
3446: PetscErrorCode PetscSectionSymCopy(PetscSectionSym sym, PetscSectionSym nsym)
3447: {
3448:   PetscFunctionBegin;
3451:   PetscTryTypeMethod(sym, copy, nsym);
3452:   PetscFunctionReturn(PETSC_SUCCESS);
3453: }

3455: /*@
3456:   PetscSectionSymDistribute - Distribute the symmetries in accordance with the input `PetscSF`

3458:   Collective

3460:   Input Parameters:
3461: + sym - the `PetscSectionSym`
3462: - migrationSF - the distribution map from roots to leaves

3464:   Output Parameters:
3465: . dsym - the redistributed symmetries

3467:   Level: developer

3469: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionSymCreate()`, `PetscSectionSetSym()`, `PetscSectionGetSym()`, `PetscSectionSymLabelSetStratum()`, `PetscSectionGetPointSyms()`
3470: @*/
3471: PetscErrorCode PetscSectionSymDistribute(PetscSectionSym sym, PetscSF migrationSF, PetscSectionSym *dsym)
3472: {
3473:   PetscFunctionBegin;
3477:   PetscTryTypeMethod(sym, distribute, migrationSF, dsym);
3478:   PetscFunctionReturn(PETSC_SUCCESS);
3479: }

3481: /*@
3482:   PetscSectionGetUseFieldOffsets - Get the flag to use field offsets directly in a global section, rather than just the point offset

3484:   Not Collective

3486:   Input Parameter:
3487: . s - the global `PetscSection`

3489:   Output Parameters:
3490: . flg - the flag

3492:   Level: developer

3494: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionSetChart()`, `PetscSectionCreate()`
3495: @*/
3496: PetscErrorCode PetscSectionGetUseFieldOffsets(PetscSection s, PetscBool *flg)
3497: {
3498:   PetscFunctionBegin;
3500:   *flg = s->useFieldOff;
3501:   PetscFunctionReturn(PETSC_SUCCESS);
3502: }

3504: /*@
3505:   PetscSectionSetUseFieldOffsets - Set the flag to use field offsets directly in a global section, rather than just the point offset

3507:   Not Collective

3509:   Input Parameters:
3510: + s   - the global `PetscSection`
3511: - flg - the flag

3513:   Level: developer

3515: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionGetUseFieldOffsets()`, `PetscSectionSetChart()`, `PetscSectionCreate()`
3516: @*/
3517: PetscErrorCode PetscSectionSetUseFieldOffsets(PetscSection s, PetscBool flg)
3518: {
3519:   PetscFunctionBegin;
3521:   s->useFieldOff = flg;
3522:   PetscFunctionReturn(PETSC_SUCCESS);
3523: }

3525: #define PetscSectionExpandPoints_Loop(TYPE) \
3526:   { \
3527:     PetscInt i, n, o0, o1, size; \
3528:     TYPE    *a0 = (TYPE *)origArray, *a1; \
3529:     PetscCall(PetscSectionGetStorageSize(s, &size)); \
3530:     PetscCall(PetscMalloc1(size, &a1)); \
3531:     for (i = 0; i < npoints; i++) { \
3532:       PetscCall(PetscSectionGetOffset(origSection, points_[i], &o0)); \
3533:       PetscCall(PetscSectionGetOffset(s, i, &o1)); \
3534:       PetscCall(PetscSectionGetDof(s, i, &n)); \
3535:       PetscCall(PetscMemcpy(&a1[o1], &a0[o0], n *unitsize)); \
3536:     } \
3537:     *newArray = (void *)a1; \
3538:   }

3540: /*@
3541:   PetscSectionExtractDofsFromArray - Extracts elements of an array corresponding to DOFs of specified points.

3543:   Not Collective

3545:   Input Parameters:
3546: + origSection - the `PetscSection` describing the layout of the array
3547: . dataType - `MPI_Datatype` describing the data type of the array (currently only `MPIU_INT`, `MPIU_SCALAR`, `MPIU_REAL`)
3548: . origArray - the array; its size must be equal to the storage size of origSection
3549: - points - `IS` with points to extract; its indices must lie in the chart of origSection

3551:   Output Parameters:
3552: + newSection - the new `PetscSection` describing the layout of the new array (with points renumbered 0,1,... but preserving numbers of DOFs)
3553: - newArray - the array of the extracted DOFs; its size is the storage size of newSection

3555:   Level: developer

3557: .seealso: [PetscSection](sec_petscsection), `PetscSectionSym`, `PetscSectionGetChart()`, `PetscSectionGetDof()`, `PetscSectionGetStorageSize()`, `PetscSectionCreate()`
3558: @*/
3559: PetscErrorCode PetscSectionExtractDofsFromArray(PetscSection origSection, MPI_Datatype dataType, const void *origArray, IS points, PetscSection *newSection, void *newArray[])
3560: {
3561:   PetscSection    s;
3562:   const PetscInt *points_;
3563:   PetscInt        i, n, npoints, pStart, pEnd;
3564:   PetscMPIInt     unitsize;

3566:   PetscFunctionBegin;
3572:   PetscCallMPI(MPI_Type_size(dataType, &unitsize));
3573:   PetscCall(ISGetLocalSize(points, &npoints));
3574:   PetscCall(ISGetIndices(points, &points_));
3575:   PetscCall(PetscSectionGetChart(origSection, &pStart, &pEnd));
3576:   PetscCall(PetscSectionCreate(PETSC_COMM_SELF, &s));
3577:   PetscCall(PetscSectionSetChart(s, 0, npoints));
3578:   for (i = 0; i < npoints; i++) {
3579:     PetscCheck(points_[i] >= pStart && points_[i] < pEnd, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "point %" PetscInt_FMT " (index %" PetscInt_FMT ") in input IS out of input section's chart", points_[i], i);
3580:     PetscCall(PetscSectionGetDof(origSection, points_[i], &n));
3581:     PetscCall(PetscSectionSetDof(s, i, n));
3582:   }
3583:   PetscCall(PetscSectionSetUp(s));
3584:   if (newArray) {
3585:     if (dataType == MPIU_INT) {
3586:       PetscSectionExpandPoints_Loop(PetscInt);
3587:     } else if (dataType == MPIU_SCALAR) {
3588:       PetscSectionExpandPoints_Loop(PetscScalar);
3589:     } else if (dataType == MPIU_REAL) {
3590:       PetscSectionExpandPoints_Loop(PetscReal);
3591:     } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "not implemented for this MPI_Datatype");
3592:   }
3593:   if (newSection) {
3594:     *newSection = s;
3595:   } else {
3596:     PetscCall(PetscSectionDestroy(&s));
3597:   }
3598:   PetscCall(ISRestoreIndices(points, &points_));
3599:   PetscFunctionReturn(PETSC_SUCCESS);
3600: }