Actual source code: inherit.c
1: /*
2: Provides utility routines for manipulating any type of PETSc object.
3: */
4: #include <petsc/private/petscimpl.h>
5: #include <petscviewer.h>
7: PETSC_INTERN PetscObject *PetscObjects;
8: PETSC_INTERN PetscInt PetscObjectsCounts;
9: PETSC_INTERN PetscInt PetscObjectsMaxCounts;
10: PETSC_INTERN PetscBool PetscObjectsLog;
12: PetscObject *PetscObjects = NULL;
13: PetscInt PetscObjectsCounts = 0, PetscObjectsMaxCounts = 0;
14: PetscBool PetscObjectsLog = PETSC_FALSE;
16: PetscObjectId PetscObjectNewId_Internal(void)
17: {
18: static PetscObjectId idcnt = 1;
19: return idcnt++;
20: }
22: PetscErrorCode PetscHeaderCreate_Function(PetscErrorCode ierr, PetscObject *h, PetscClassId classid, const char class_name[], const char descr[], const char mansec[], MPI_Comm comm, PetscObjectDestroyFn *destroy, PetscObjectViewFn *view)
23: {
24: PetscFunctionBegin;
25: if (ierr) PetscFunctionReturn(ierr);
26: PetscCall(PetscHeaderCreate_Private(*h, classid, class_name, descr, mansec, comm, destroy, view));
27: PetscCall(PetscLogObjectCreate(*h));
28: PetscFunctionReturn(PETSC_SUCCESS);
29: }
31: /*
32: PetscHeaderCreate_Private - Fills in the default values.
33: */
34: PetscErrorCode PetscHeaderCreate_Private(PetscObject h, PetscClassId classid, const char class_name[], const char descr[], const char mansec[], MPI_Comm comm, PetscObjectDestroyFn *destroy, PetscObjectViewFn *view)
35: {
36: void *get_tmp;
37: PetscInt64 *cidx;
38: PetscMPIInt iflg;
40: PetscFunctionBegin;
41: h->classid = classid;
42: h->class_name = (char *)class_name;
43: h->description = (char *)descr;
44: h->mansec = (char *)mansec;
45: h->refct = 1;
46: h->non_cyclic_references = NULL;
47: h->id = PetscObjectNewId_Internal();
48: h->bops->destroy = destroy;
49: h->bops->view = view;
51: PetscCall(PetscCommDuplicate(comm, &h->comm, &h->tag));
53: /* Increment and store current object creation index */
54: PetscCallMPI(MPI_Comm_get_attr(h->comm, Petsc_CreationIdx_keyval, &get_tmp, &iflg));
55: PetscCheck(iflg, h->comm, PETSC_ERR_ARG_CORRUPT, "MPI_Comm does not have an object creation index");
56: cidx = (PetscInt64 *)get_tmp;
57: h->cidx = (*cidx)++;
59: /* Keep a record of object created */
60: if (PetscDefined(USE_LOG) && PetscObjectsLog) {
61: PetscObject *newPetscObjects;
62: PetscInt newPetscObjectsMaxCounts;
64: PetscObjectsCounts++;
65: for (PetscInt i = 0; i < PetscObjectsMaxCounts; ++i) {
66: if (!PetscObjects[i]) {
67: PetscObjects[i] = h;
68: PetscFunctionReturn(PETSC_SUCCESS);
69: }
70: }
71: /* Need to increase the space for storing PETSc objects */
72: if (!PetscObjectsMaxCounts) newPetscObjectsMaxCounts = 100;
73: else newPetscObjectsMaxCounts = 2 * PetscObjectsMaxCounts;
74: PetscCall(PetscCalloc1(newPetscObjectsMaxCounts, &newPetscObjects));
75: PetscCall(PetscArraycpy(newPetscObjects, PetscObjects, PetscObjectsMaxCounts));
76: PetscCall(PetscFree(PetscObjects));
78: PetscObjects = newPetscObjects;
79: PetscObjects[PetscObjectsMaxCounts] = h;
80: PetscObjectsMaxCounts = newPetscObjectsMaxCounts;
81: }
82: PetscFunctionReturn(PETSC_SUCCESS);
83: }
85: PETSC_INTERN PetscBool PetscMemoryCollectMaximumUsage;
86: PETSC_INTERN PetscLogDouble PetscMemoryMaximumUsage;
88: PetscErrorCode PetscHeaderDestroy_Function(PetscObject *h)
89: {
90: PetscFunctionBegin;
91: PetscCall(PetscLogObjectDestroy(*h));
92: PetscCall(PetscHeaderDestroy_Private(*h, PETSC_FALSE));
93: PetscCall(PetscFree(*h));
94: PetscFunctionReturn(PETSC_SUCCESS);
95: }
97: /*
98: PetscHeaderDestroy_Private - Destroys a base PETSc object header. Called by
99: the macro PetscHeaderDestroy().
100: */
101: PetscErrorCode PetscHeaderDestroy_Private(PetscObject obj, PetscBool clear_for_reuse)
102: {
103: PetscFunctionBegin;
105: PetscCall(PetscComposedQuantitiesDestroy(obj));
106: if (PetscMemoryCollectMaximumUsage) {
107: PetscLogDouble usage;
109: PetscCall(PetscMemoryGetCurrentUsage(&usage));
110: if (usage > PetscMemoryMaximumUsage) PetscMemoryMaximumUsage = usage;
111: }
112: /* first destroy things that could execute arbitrary code */
113: if (obj->python_destroy) {
114: void *python_context = obj->python_context;
115: PetscErrorCode (*python_destroy)(void *) = obj->python_destroy;
117: obj->python_context = NULL;
118: obj->python_destroy = NULL;
119: PetscCall((*python_destroy)(python_context));
120: }
121: PetscCall(PetscObjectDestroyOptionsHandlers(obj));
122: PetscCall(PetscObjectListDestroy(&obj->olist));
124: /* destroy allocated quantities */
125: if (PetscPrintFunctionList) PetscCall(PetscFunctionListPrintNonEmpty(obj->qlist));
126: PetscCheck(--obj->refct <= 0, obj->comm, PETSC_ERR_PLIB, "Destroying a PetscObject (%s) with reference count %" PetscInt_FMT " >= 1", obj->name ? obj->name : "unnamed", obj->refct);
127: PetscCall(PetscFree(obj->name));
128: PetscCall(PetscFree(obj->prefix));
129: PetscCall(PetscFree(obj->type_name));
131: if (clear_for_reuse) {
132: /* we will assume that obj->bops->view and destroy are safe to leave as-is */
134: /* reset quantities, in order of appearance in _p_PetscObject */
135: obj->id = PetscObjectNewId_Internal();
136: obj->refct = 1;
137: obj->tablevel = 0;
138: obj->state = 0;
139: /* don't deallocate, zero these out instead */
140: PetscCall(PetscFunctionListClear(obj->qlist));
141: PetscCall(PetscArrayzero(obj->fortran_func_pointers, obj->num_fortran_func_pointers));
142: PetscCall(PetscArrayzero(obj->fortrancallback[PETSC_FORTRAN_CALLBACK_CLASS], obj->num_fortrancallback[PETSC_FORTRAN_CALLBACK_CLASS]));
143: PetscCall(PetscArrayzero(obj->fortrancallback[PETSC_FORTRAN_CALLBACK_SUBTYPE], obj->num_fortrancallback[PETSC_FORTRAN_CALLBACK_SUBTYPE]));
144: obj->optionsprinted = PETSC_FALSE;
145: #if PetscDefined(HAVE_SAWS)
146: obj->amsmem = PETSC_FALSE;
147: obj->amspublishblock = PETSC_FALSE;
148: #endif
149: obj->options = NULL;
150: obj->donotPetscObjectPrintClassNamePrefixType = PETSC_FALSE;
151: } else {
152: PetscCall(PetscFunctionListDestroy(&obj->qlist));
153: PetscCall(PetscFree(obj->fortran_func_pointers));
154: PetscCall(PetscFree(obj->fortrancallback[PETSC_FORTRAN_CALLBACK_CLASS]));
155: PetscCall(PetscFree(obj->fortrancallback[PETSC_FORTRAN_CALLBACK_SUBTYPE]));
156: PetscCall(PetscCommDestroy(&obj->comm));
157: obj->classid = PETSCFREEDHEADER;
159: if (PetscDefined(USE_LOG) && PetscObjectsLog) {
160: /* Record object removal from list of all objects */
161: for (PetscInt i = 0; i < PetscObjectsMaxCounts; ++i) {
162: if (PetscObjects[i] == obj) {
163: PetscObjects[i] = NULL;
164: --PetscObjectsCounts;
165: break;
166: }
167: }
168: if (!PetscObjectsCounts) {
169: PetscCall(PetscFree(PetscObjects));
170: PetscObjectsMaxCounts = 0;
171: }
172: }
173: }
174: PetscFunctionReturn(PETSC_SUCCESS);
175: }
177: /*
178: PetscHeaderReset_Internal - "Reset" a PetscObject header. This is tantamount to destroying
179: the object but does not free all resources. The object retains its:
181: - classid
182: - bops->view
183: - bops->destroy
184: - comm
185: - tag
186: - class_name
187: - description
188: - mansec
189: - cpp
191: Note that while subclass information is lost, superclass info remains. Thus this function is
192: intended to be used to reuse a PetscObject within the same class to avoid reallocating its
193: resources.
194: */
195: PetscErrorCode PetscHeaderReset_Internal(PetscObject obj)
196: {
197: PetscFunctionBegin;
198: PetscCall(PetscHeaderDestroy_Private(obj, PETSC_TRUE));
199: PetscFunctionReturn(PETSC_SUCCESS);
200: }
202: /*@
203: PetscObjectCopyFortranFunctionPointers - Copy function pointers to another object
205: Logically Collective
207: Input Parameters:
208: + src - source object
209: - dest - destination object
211: Level: developer
213: Note:
214: Both objects must have the same class.
216: This is used to help manage user callback functions that were provided in Fortran
218: .seealso: `PetscFortranCallbackRegister()`, `PetscFortranCallbackGetSizes()`
219: @*/
220: PetscErrorCode PetscObjectCopyFortranFunctionPointers(PetscObject src, PetscObject dest)
221: {
222: PetscFortranCallbackId cbtype, numcb[PETSC_FORTRAN_CALLBACK_MAXTYPE];
224: PetscFunctionBegin;
227: PetscCheck(src->classid == dest->classid, src->comm, PETSC_ERR_ARG_INCOMP, "Objects must be of the same class");
229: PetscCall(PetscFree(dest->fortran_func_pointers));
230: PetscCall(PetscMalloc(src->num_fortran_func_pointers * sizeof(PetscFortranCallbackFn *), &dest->fortran_func_pointers));
231: PetscCall(PetscArraycpy(dest->fortran_func_pointers, src->fortran_func_pointers, src->num_fortran_func_pointers));
233: dest->num_fortran_func_pointers = src->num_fortran_func_pointers;
235: PetscCall(PetscFortranCallbackGetSizes(src->classid, &numcb[PETSC_FORTRAN_CALLBACK_CLASS], &numcb[PETSC_FORTRAN_CALLBACK_SUBTYPE]));
236: for (cbtype = PETSC_FORTRAN_CALLBACK_CLASS; cbtype < PETSC_FORTRAN_CALLBACK_MAXTYPE; cbtype++) {
237: PetscCall(PetscFree(dest->fortrancallback[cbtype]));
238: PetscCall(PetscCalloc1(numcb[cbtype], &dest->fortrancallback[cbtype]));
239: PetscCall(PetscArraycpy(dest->fortrancallback[cbtype], src->fortrancallback[cbtype], src->num_fortrancallback[cbtype]));
240: dest->num_fortrancallback[cbtype] = src->num_fortrancallback[cbtype];
241: }
242: PetscFunctionReturn(PETSC_SUCCESS);
243: }
245: /*@C
246: PetscObjectSetFortranCallback - set Fortran callback function pointer and context
248: Logically Collective, No Fortran Support
250: Input Parameters:
251: + obj - object on which to set callback
252: . cbtype - callback type (class or subtype)
253: . cid - address of callback Id, updated if not yet initialized (zero)
254: . func - Fortran function
255: - ctx - Fortran context
257: Level: developer
259: Note:
260: This is used to help manage user callback functions that were provided in Fortran
262: .seealso: `PetscObjectGetFortranCallback()`, `PetscFortranCallbackRegister()`, `PetscFortranCallbackGetSizes()`
263: @*/
264: PetscErrorCode PetscObjectSetFortranCallback(PetscObject obj, PetscFortranCallbackType cbtype, PetscFortranCallbackId *cid, PetscFortranCallbackFn *func, PetscCtx ctx)
265: {
266: const char *subtype = NULL;
268: PetscFunctionBegin;
270: if (cbtype == PETSC_FORTRAN_CALLBACK_SUBTYPE) subtype = obj->type_name;
271: if (!*cid) PetscCall(PetscFortranCallbackRegister(obj->classid, subtype, cid));
272: if (*cid >= PETSC_SMALLEST_FORTRAN_CALLBACK + obj->num_fortrancallback[cbtype]) {
273: PetscFortranCallbackId oldnum = obj->num_fortrancallback[cbtype];
274: PetscFortranCallbackId newnum = PetscMax(*cid - PETSC_SMALLEST_FORTRAN_CALLBACK + 1, 2 * oldnum);
275: PetscFortranCallback *callback;
276: PetscCall(PetscMalloc1(newnum, &callback));
277: PetscCall(PetscArraycpy(callback, obj->fortrancallback[cbtype], oldnum));
278: PetscCall(PetscFree(obj->fortrancallback[cbtype]));
280: obj->fortrancallback[cbtype] = callback;
281: obj->num_fortrancallback[cbtype] = newnum;
282: }
283: obj->fortrancallback[cbtype][*cid - PETSC_SMALLEST_FORTRAN_CALLBACK].func = func;
284: obj->fortrancallback[cbtype][*cid - PETSC_SMALLEST_FORTRAN_CALLBACK].ctx = ctx;
285: PetscFunctionReturn(PETSC_SUCCESS);
286: }
288: /*@C
289: PetscObjectGetFortranCallback - get Fortran callback function pointer and context
291: Logically Collective, No Fortran Support
293: Input Parameters:
294: + obj - object on which to get callback
295: . cbtype - callback type
296: - cid - address of callback Id
298: Output Parameters:
299: + func - Fortran function (or `NULL` if not needed)
300: - ctx - Fortran context (or `NULL` if not needed)
302: Level: developer
304: Note:
305: This is used to help manage user callback functions that were provided in Fortran
307: .seealso: `PetscObjectSetFortranCallback()`, `PetscFortranCallbackRegister()`, `PetscFortranCallbackGetSizes()`
308: @*/
309: PetscErrorCode PetscObjectGetFortranCallback(PetscObject obj, PetscFortranCallbackType cbtype, PetscFortranCallbackId cid, PetscFortranCallbackFn **func, void **ctx)
310: {
311: PetscFortranCallback *cb;
313: PetscFunctionBegin;
315: PetscCheck(cid >= PETSC_SMALLEST_FORTRAN_CALLBACK, obj->comm, PETSC_ERR_ARG_CORRUPT, "Fortran callback Id invalid");
316: PetscCheck(cid < PETSC_SMALLEST_FORTRAN_CALLBACK + obj->num_fortrancallback[cbtype], obj->comm, PETSC_ERR_ARG_CORRUPT, "Fortran callback not set on this object");
317: cb = &obj->fortrancallback[cbtype][cid - PETSC_SMALLEST_FORTRAN_CALLBACK];
318: if (func) *func = cb->func;
319: if (ctx) *ctx = cb->ctx;
320: PetscFunctionReturn(PETSC_SUCCESS);
321: }
323: #if defined(PETSC_USE_LOG)
324: /*@C
325: PetscObjectsDump - Prints all the currently existing objects.
327: Input Parameters:
328: + fd - file pointer
329: - all - by default only tries to display objects created explicitly by the user, if all is `PETSC_TRUE` then lists all outstanding objects
331: Options Database Key:
332: . -objects_dump all - print information about all the objects that exist at the end of the programs run
334: Level: advanced
336: Note:
337: Only MPI rank 0 of `PETSC_COMM_WORLD` prints the values
339: .seealso: `PetscObject`
340: @*/
341: PetscErrorCode PetscObjectsDump(FILE *fd, PetscBool all)
342: {
343: PetscInt i, j, k = 0;
344: PetscObject h;
346: PetscFunctionBegin;
347: if (PetscObjectsCounts) {
348: PetscCall(PetscFPrintf(PETSC_COMM_WORLD, fd, "The following objects were never freed\n"));
349: PetscCall(PetscFPrintf(PETSC_COMM_WORLD, fd, "-----------------------------------------\n"));
350: for (i = 0; i < PetscObjectsMaxCounts; i++) {
351: if ((h = PetscObjects[i])) {
352: PetscCall(PetscObjectName(h));
353: {
354: PetscStack *stack = NULL;
355: char *create = NULL, *rclass = NULL;
357: /* if the PETSc function the user calls is not a create then this object was NOT directly created by them */
358: PetscCall(PetscMallocGetStack(h, &stack));
359: if (stack) {
360: k = stack->currentsize - 2;
361: if (!all) {
362: k = 0;
363: while (!stack->petscroutine[k]) k++;
364: PetscCall(PetscStrstr(stack->function[k], "Create", &create));
365: if (!create) PetscCall(PetscStrstr(stack->function[k], "Get", &create));
366: PetscCall(PetscStrstr(stack->function[k], h->class_name, &rclass));
367: if (!create) continue;
368: if (!rclass) continue;
369: }
370: }
372: PetscCall(PetscFPrintf(PETSC_COMM_WORLD, fd, "[%d] %s %s %s\n", PetscGlobalRank, h->class_name, h->type_name, h->name));
374: PetscCall(PetscMallocGetStack(h, &stack));
375: if (stack) {
376: for (j = k; j >= 0; j--) fprintf(fd, " [%d] %s() in %s\n", PetscGlobalRank, stack->function[j], stack->file[j]);
377: }
378: }
379: }
380: }
381: }
382: PetscFunctionReturn(PETSC_SUCCESS);
383: }
385: /*@
386: PetscObjectsView - Prints the currently existing objects.
388: Logically Collective
390: Input Parameter:
391: . viewer - must be an `PETSCVIEWERASCII` viewer
393: Level: advanced
395: .seealso: `PetscObject`
396: @*/
397: PetscErrorCode PetscObjectsView(PetscViewer viewer)
398: {
399: PetscBool isascii;
400: FILE *fd;
402: PetscFunctionBegin;
403: if (!viewer) viewer = PETSC_VIEWER_STDOUT_WORLD;
404: PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &isascii));
405: PetscCheck(isascii, PetscObjectComm((PetscObject)viewer), PETSC_ERR_SUP, "Only supports ASCII viewer");
406: PetscCall(PetscViewerASCIIGetPointer(viewer, &fd));
407: PetscCall(PetscObjectsDump(fd, PETSC_TRUE));
408: PetscFunctionReturn(PETSC_SUCCESS);
409: }
411: /*@
412: PetscObjectsGetObject - Get a pointer to a named object
414: Not Collective
416: Input Parameter:
417: . name - the name of an object
419: Output Parameters:
420: + obj - the object or `NULL` if there is no object, optional, pass in `NULL` if not needed
421: - classname - the name of the class of the object, optional, pass in `NULL` if not needed
423: Level: advanced
425: .seealso: `PetscObject`
426: @*/
427: PetscErrorCode PetscObjectsGetObject(const char name[], PetscObject *obj, const char *classname[])
428: {
429: PetscObject h;
430: PetscBool flg;
432: PetscFunctionBegin;
433: PetscAssertPointer(name, 1);
434: if (obj) *obj = NULL;
435: for (PetscInt i = 0; i < PetscObjectsMaxCounts; i++) {
436: if ((h = PetscObjects[i])) {
437: PetscCall(PetscObjectName(h));
438: PetscCall(PetscStrcmp(h->name, name, &flg));
439: if (flg) {
440: if (obj) *obj = h;
441: if (classname) *classname = h->class_name;
442: PetscFunctionReturn(PETSC_SUCCESS);
443: }
444: }
445: }
446: PetscFunctionReturn(PETSC_SUCCESS);
447: }
448: #else
449: PetscErrorCode PetscObjectsView(PetscViewer viewer)
450: {
451: PetscFunctionReturn(PETSC_SUCCESS);
452: }
454: PetscErrorCode PetscObjectsGetObject(const char name[], PetscObject *obj, const char *classname[])
455: {
456: PetscFunctionReturn(PETSC_SUCCESS);
457: }
458: #endif
460: /*@
461: PetscObjectSetPrintedOptions - indicate to an object that it should behave as if it has already printed the help for its options so it will not display the help message
463: Input Parameter:
464: . obj - the `PetscObject`
466: Level: developer
468: Developer Notes:
469: This is used, for example to prevent sequential objects that are created from a parallel object; such as the `KSP` created by
470: `PCBJACOBI` from all printing the same help messages to the screen
472: .seealso: `PetscOptionsInsert()`, `PetscObject`
473: @*/
474: PetscErrorCode PetscObjectSetPrintedOptions(PetscObject obj)
475: {
476: PetscFunctionBegin;
477: PetscAssertPointer(obj, 1);
478: obj->optionsprinted = PETSC_TRUE;
479: PetscFunctionReturn(PETSC_SUCCESS);
480: }
482: /*@
483: PetscObjectInheritPrintedOptions - If the child object is not on the MPI rank 0 process of the parent object and the child is sequential then the child gets it set.
485: Input Parameters:
486: + pobj - the parent object
487: - obj - the `PetscObject`
489: Level: developer
491: Developer Notes:
492: This is used, for example to prevent sequential objects that are created from a parallel object; such as the `KSP` created by
493: `PCBJACOBI` from all printing the same help messages to the screen
495: This will not handle more complicated situations like with `PCGASM` where children may live on any subset of the parent's processes and overlap
497: .seealso: `PetscOptionsInsert()`, `PetscObjectSetPrintedOptions()`, `PetscObject`
498: @*/
499: PetscErrorCode PetscObjectInheritPrintedOptions(PetscObject pobj, PetscObject obj)
500: {
501: PetscMPIInt prank, size;
503: PetscFunctionBegin;
506: PetscCallMPI(MPI_Comm_rank(pobj->comm, &prank));
507: PetscCallMPI(MPI_Comm_size(obj->comm, &size));
508: if (size == 1 && prank > 0) obj->optionsprinted = PETSC_TRUE;
509: PetscFunctionReturn(PETSC_SUCCESS);
510: }
512: /*@C
513: PetscObjectAddOptionsHandler - Adds an additional function to check for options when `XXXSetFromOptions()` is called.
515: Not Collective
517: Input Parameters:
518: + obj - the PETSc object
519: . handle - function that checks for options
520: . destroy - function to destroy `ctx` if provided
521: - ctx - optional context for check function
523: Calling sequence of `handle`:
524: + obj - the PETSc object
525: . PetscOptionsObject - the `PetscOptionItems` object
526: - ctx - optional context for `handle`
528: Calling sequence of `destroy`:
529: + obj - the PETSc object
530: - ctx - optional context for `handle`
532: Level: developer
534: .seealso: `KSPSetFromOptions()`, `PCSetFromOptions()`, `SNESSetFromOptions()`, `PetscObjectProcessOptionsHandlers()`, `PetscObjectDestroyOptionsHandlers()`,
535: `PetscObject`
536: @*/
537: PetscErrorCode PetscObjectAddOptionsHandler(PetscObject obj, PetscErrorCode (*handle)(PetscObject obj, PetscOptionItems PetscOptionsObject, PetscCtx ctx), PetscErrorCode (*destroy)(PetscObject obj, PetscCtxRt ctx), PetscCtx ctx)
538: {
539: PetscFunctionBegin;
541: for (PetscInt i = 0; i < obj->noptionhandler; i++) {
542: PetscBool identical = (PetscBool)(obj->optionhandler[i] == handle && obj->optiondestroy[i] == destroy && obj->optionctx[i] == ctx);
543: if (identical) PetscFunctionReturn(PETSC_SUCCESS);
544: }
545: PetscCheck(obj->noptionhandler < PETSC_MAX_OPTIONS_HANDLER, obj->comm, PETSC_ERR_ARG_OUTOFRANGE, "Too many options handlers added");
546: obj->optionhandler[obj->noptionhandler] = handle;
547: obj->optiondestroy[obj->noptionhandler] = destroy;
548: obj->optionctx[obj->noptionhandler++] = ctx;
549: PetscFunctionReturn(PETSC_SUCCESS);
550: }
552: /*@C
553: PetscObjectProcessOptionsHandlers - Calls all the options handlers attached to an object
555: Not Collective
557: Input Parameters:
558: + obj - the PETSc object
559: - PetscOptionsObject - the options context
561: Level: developer
563: .seealso: `KSPSetFromOptions()`, `PCSetFromOptions()`, `SNESSetFromOptions()`, `PetscObjectAddOptionsHandler()`, `PetscObjectDestroyOptionsHandlers()`,
564: `PetscObject`
565: @*/
566: PetscErrorCode PetscObjectProcessOptionsHandlers(PetscObject obj, PetscOptionItems PetscOptionsObject)
567: {
568: PetscFunctionBegin;
570: for (PetscInt i = 0; i < obj->noptionhandler; i++) PetscCall((*obj->optionhandler[i])(obj, PetscOptionsObject, obj->optionctx[i]));
571: PetscFunctionReturn(PETSC_SUCCESS);
572: }
574: /*@
575: PetscObjectDestroyOptionsHandlers - Destroys all the option handlers attached to an object
577: Not Collective
579: Input Parameter:
580: . obj - the PETSc object
582: Level: developer
584: .seealso: `KSPSetFromOptions()`, `PCSetFromOptions()`, `SNESSetFromOptions()`, `PetscObjectAddOptionsHandler()`, `PetscObjectProcessOptionsHandlers()`,
585: `PetscObject`
586: @*/
587: PetscErrorCode PetscObjectDestroyOptionsHandlers(PetscObject obj)
588: {
589: PetscFunctionBegin;
591: for (PetscInt i = 0; i < obj->noptionhandler; i++) {
592: if (obj->optiondestroy[i]) PetscCall((*obj->optiondestroy[i])(obj, obj->optionctx[i]));
593: }
594: obj->noptionhandler = 0;
595: PetscFunctionReturn(PETSC_SUCCESS);
596: }
598: /*@
599: PetscObjectReference - Indicates to a `PetscObject` that it is being
600: referenced by another `PetscObject`. This increases the reference
601: count for that object by one.
603: Logically Collective
605: Input Parameter:
606: . obj - the PETSc object. This must be cast with (`PetscObject`), for example, `PetscObjectReference`((`PetscObject`)mat);
608: Level: advanced
610: Note:
611: If `obj` is `NULL` this function returns without doing anything.
613: .seealso: `PetscObjectCompose()`, `PetscObjectDereference()`, `PetscObject`
614: @*/
615: PetscErrorCode PetscObjectReference(PetscObject obj)
616: {
617: PetscFunctionBegin;
618: if (!obj) PetscFunctionReturn(PETSC_SUCCESS);
620: obj->refct++;
621: PetscFunctionReturn(PETSC_SUCCESS);
622: }
624: /*@
625: PetscObjectGetReference - Gets the current reference count for a PETSc object.
627: Not Collective
629: Input Parameter:
630: . obj - the PETSc object; this must be cast with (`PetscObject`), for example,
631: `PetscObjectGetReference`((`PetscObject`)mat,&cnt); `obj` cannot be `NULL`
633: Output Parameter:
634: . cnt - the reference count
636: Level: advanced
638: .seealso: `PetscObjectCompose()`, `PetscObjectDereference()`, `PetscObjectReference()`, `PetscObject`
639: @*/
640: PetscErrorCode PetscObjectGetReference(PetscObject obj, PetscInt *cnt)
641: {
642: PetscFunctionBegin;
644: PetscAssertPointer(cnt, 2);
645: *cnt = obj->refct;
646: PetscFunctionReturn(PETSC_SUCCESS);
647: }
649: /*@
650: PetscObjectDereference - Indicates to any `PetscObject` that it is being
651: referenced by one less `PetscObject`. This decreases the reference
652: count for that object by one.
654: Collective on `obj` if reference reaches 0 otherwise Logically Collective
656: Input Parameter:
657: . obj - the PETSc object; this must be cast with (`PetscObject`), for example,
658: `PetscObjectDereference`((`PetscObject`)mat);
660: Level: advanced
662: Notes:
663: `PetscObjectDestroy()` sets the `obj` pointer to `NULL` after the call, this routine does not.
665: If `obj` is `NULL` this function returns without doing anything.
667: .seealso: `PetscObjectCompose()`, `PetscObjectReference()`, `PetscObjectDestroy()`, `PetscObject`
668: @*/
669: PetscErrorCode PetscObjectDereference(PetscObject obj)
670: {
671: PetscFunctionBegin;
672: if (!obj) PetscFunctionReturn(PETSC_SUCCESS);
674: if (obj->bops->destroy) PetscCall((*obj->bops->destroy)(&obj));
675: else PetscCheck(--obj->refct, PETSC_COMM_SELF, PETSC_ERR_SUP, "This PETSc object does not have a generic destroy routine");
676: PetscFunctionReturn(PETSC_SUCCESS);
677: }
679: /*
680: The following routines are the versions private to the PETSc object
681: data structures.
682: */
683: PetscErrorCode PetscObjectRemoveReference(PetscObject obj, const char name[])
684: {
685: PetscFunctionBegin;
687: PetscCall(PetscObjectListRemoveReference(&obj->olist, name));
688: PetscFunctionReturn(PETSC_SUCCESS);
689: }
691: /*@
692: PetscObjectCompose - Associates another PETSc object with a given PETSc object.
694: Not Collective
696: Input Parameters:
697: + obj - the PETSc object; this must be cast with (`PetscObject`), for example,
698: `PetscObjectCompose`((`PetscObject`)mat,...);
699: . name - name associated with the child object
700: - ptr - the other PETSc object to associate with the PETSc object; this must also be
701: cast with (`PetscObject`)
703: Level: advanced
705: Notes:
706: The second objects reference count is automatically increased by one when it is
707: composed.
709: Replaces any previous object that had been composed with the same name.
711: If `ptr` is `NULL` and `name` has previously been composed using an object, then that
712: entry is removed from `obj`.
714: `PetscObjectCompose()` can be used with any PETSc object (such as
715: `Mat`, `Vec`, `KSP`, `SNES`, etc.) or any user-provided object.
717: `PetscContainerCreate()` or `PetscObjectContainerCompose()` can be used to create an object from a
718: user-provided pointer that may then be composed with PETSc objects using `PetscObjectCompose()`
720: Fortran Note:
721: Use
722: .vb
723: call PetscObjectCompose(obj, name, PetscObjectCast(ptr), ierr)
724: .ve
726: .seealso: `PetscObjectQuery()`, `PetscContainerCreate()`, `PetscObjectComposeFunction()`, `PetscObjectQueryFunction()`, `PetscContainer`,
727: `PetscContainerSetPointer()`, `PetscObject`, `PetscObjectContainerCompose()`
728: @*/
729: PetscErrorCode PetscObjectCompose(PetscObject obj, const char name[], PetscObject ptr)
730: {
731: PetscFunctionBegin;
733: PetscAssertPointer(name, 2);
735: PetscCheck(obj != ptr, PetscObjectComm(obj), PETSC_ERR_SUP, "Cannot compose object with itself");
736: if (ptr) {
737: const char *tname;
738: PetscBool skipreference;
740: PetscCall(PetscObjectListReverseFind(ptr->olist, obj, &tname, &skipreference));
741: if (tname) PetscCheck(skipreference, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "An object cannot be composed with an object that was composed with it");
742: }
743: PetscCall(PetscObjectListAdd(&obj->olist, name, ptr));
744: PetscFunctionReturn(PETSC_SUCCESS);
745: }
747: /*@
748: PetscObjectQuery - Gets a PETSc object associated with a given object that was composed with `PetscObjectCompose()`
750: Not Collective
752: Input Parameters:
753: + obj - the PETSc object. It must be cast with a (`PetscObject`), for example,
754: `PetscObjectCompose`((`PetscObject`)mat,...);
755: . name - name associated with child object
756: - ptr - the other PETSc object associated with the PETSc object, this must be
757: cast with (`PetscObject`*)
759: Level: advanced
761: Note:
762: The reference count of neither object is increased in this call
764: Fortran Note:
765: Use
766: .vb
767: call PetscObjectQuery(PetscObjectCast(obj), name, ptr, ierr)
768: .ve
770: .seealso: `PetscObjectCompose()`, `PetscObjectComposeFunction()`, `PetscObjectQueryFunction()`, `PetscContainer`,
771: `PetscContainerGetPointer()`, `PetscObject`
772: @*/
773: PetscErrorCode PetscObjectQuery(PetscObject obj, const char name[], PetscObject *ptr)
774: {
775: PetscFunctionBegin;
777: PetscAssertPointer(name, 2);
778: PetscAssertPointer(ptr, 3);
779: PetscCall(PetscObjectListFind(obj->olist, name, ptr));
780: PetscFunctionReturn(PETSC_SUCCESS);
781: }
783: /*MC
784: PetscObjectComposeFunction - Associates a function with a given PETSc object.
786: Synopsis:
787: #include <petscsys.h>
788: PetscErrorCode PetscObjectComposeFunction(PetscObject obj, const char name[], PetscErrorCodeFn *fptr)
790: Logically Collective
792: Input Parameters:
793: + obj - the PETSc object; this must be cast with a (`PetscObject`), for example,
794: `PetscObjectCompose`((`PetscObject`)mat,...);
795: . name - name associated with the child function
796: - fptr - function pointer
798: Level: advanced
800: Notes:
801: When the first argument of `fptr` is (or is derived from) a `PetscObject` then `PetscTryMethod()` and `PetscUseMethod()`
802: can be used to call the function directly with error checking.
804: To remove a registered routine, pass in `NULL` for `fptr`.
806: `PetscObjectComposeFunction()` can be used with any PETSc object (such as
807: `Mat`, `Vec`, `KSP`, `SNES`, etc.) or any user-provided object.
809: `PetscUseTypeMethod()` and `PetscTryTypeMethod()` are used to call a function that is stored in the objects `obj->ops` table.
811: .seealso: `PetscObjectQueryFunction()`, `PetscContainerCreate()` `PetscObjectCompose()`, `PetscObjectQuery()`, `PetscTryMethod()`, `PetscUseMethod()`,
812: `PetscUseTypeMethod()`, `PetscTryTypeMethod()`, `PetscObject`
813: M*/
814: PetscErrorCode PetscObjectComposeFunction_Private(PetscObject obj, const char name[], PetscErrorCodeFn *fptr)
815: {
816: PetscFunctionBegin;
818: PetscAssertPointer(name, 2);
819: PetscCall(PetscFunctionListAdd_Private(&obj->qlist, name, fptr));
820: PetscFunctionReturn(PETSC_SUCCESS);
821: }
823: /*MC
824: PetscObjectQueryFunction - Gets a function associated with a given object.
826: Synopsis:
827: #include <petscsys.h>
828: PetscErrorCode PetscObjectQueryFunction(PetscObject obj, const char name[], PetscErrorCodeFn **fptr)
830: Logically Collective
832: Input Parameters:
833: + obj - the PETSc object; this must be cast with (`PetscObject`), for example,
834: `PetscObjectQueryFunction`((`PetscObject`)ksp,...);
835: - name - name associated with the child function
837: Output Parameter:
838: . fptr - function pointer
840: Level: advanced
842: .seealso: `PetscObjectComposeFunction()`, `PetscFunctionListFind()`, `PetscObjectCompose()`, `PetscObjectQuery()`, `PetscObject`
843: M*/
844: PETSC_EXTERN PetscErrorCode PetscObjectQueryFunction_Private(PetscObject obj, const char name[], PetscErrorCodeFn **fptr)
845: {
846: PetscFunctionBegin;
848: PetscAssertPointer(name, 2);
849: PetscCall(PetscFunctionListFind_Private(obj->qlist, name, fptr));
850: PetscFunctionReturn(PETSC_SUCCESS);
851: }
853: /*@
854: PetscObjectHasFunction - Query if a function is associated with a given object.
856: Logically Collective
858: Input Parameters:
859: + obj - the PETSc object
860: - name - name associated with the child function
862: Output Parameter:
863: . has - the boolean value
865: Level: advanced
867: .seealso: `PetscObject`, `PetscObjectComposeFunction()`, `PetscObjectQueryFunction()`
868: @*/
869: PetscErrorCode PetscObjectHasFunction(PetscObject obj, const char name[], PetscBool *has)
870: {
871: PetscErrorCodeFn *fptr = NULL;
873: PetscFunctionBegin;
874: PetscAssertPointer(has, 3);
875: PetscCall(PetscObjectQueryFunction(obj, name, &fptr));
876: *has = fptr ? PETSC_TRUE : PETSC_FALSE;
877: PetscFunctionReturn(PETSC_SUCCESS);
878: }
880: struct _p_PetscContainer {
881: PETSCHEADER(int);
882: void *ctx;
883: PetscCtxDestroyFn *ctxdestroy;
884: PetscErrorCode (*userdestroy_deprecated)(void *);
885: };
887: /*@C
888: PetscContainerGetPointer - Gets the pointer value contained in the container that was provided with `PetscContainerSetPointer()`
890: Not Collective, No Fortran Support
892: Input Parameter:
893: . obj - the object created with `PetscContainerCreate()`
895: Output Parameter:
896: . ptr - the pointer value
898: Level: advanced
900: .seealso: `PetscContainerCreate()`, `PetscContainerDestroy()`, `PetscObject`,
901: `PetscContainerSetPointer()`, `PetscObjectContainerCompose()`, `PetscObjectContainerQuery()`
902: @*/
903: PetscErrorCode PetscContainerGetPointer(PetscContainer obj, PetscCtxRt ptr)
904: {
905: PetscFunctionBegin;
907: PetscAssertPointer(ptr, 2);
908: *(void **)ptr = obj->ctx;
909: PetscFunctionReturn(PETSC_SUCCESS);
910: }
912: /*@C
913: PetscContainerSetPointer - Sets the pointer value contained in the container.
915: Logically Collective, No Fortran Support
917: Input Parameters:
918: + obj - the object created with `PetscContainerCreate()`
919: - ptr - the pointer value
921: Level: advanced
923: .seealso: `PetscContainerCreate()`, `PetscContainerDestroy()`, `PetscObjectCompose()`, `PetscObjectQuery()`, `PetscObject`,
924: `PetscContainerGetPointer()`, `PetscObjectContainerCompose()`, `PetscObjectContainerQuery()`
925: @*/
926: PetscErrorCode PetscContainerSetPointer(PetscContainer obj, void *ptr)
927: {
928: PetscFunctionBegin;
930: if (ptr) PetscAssertPointer(ptr, 2);
931: obj->ctx = ptr;
932: PetscFunctionReturn(PETSC_SUCCESS);
933: }
935: /*@C
936: PetscContainerDestroy - Destroys a PETSc container object.
938: Collective, No Fortran Support
940: Input Parameter:
941: . obj - an object that was created with `PetscContainerCreate()`
943: Level: advanced
945: Note:
946: If `PetscContainerSetCtxDestroy()` was used to provide a user destroy object for the data provided with `PetscContainerSetPointer()`
947: then that function is called to destroy the data.
949: .seealso: `PetscContainerCreate()`, `PetscContainerSetCtxDestroy()`, `PetscObject`, `PetscObjectContainerCompose()`, `PetscObjectContainerQuery()`
950: @*/
951: PetscErrorCode PetscContainerDestroy(PetscContainer *obj)
952: {
953: PetscFunctionBegin;
954: if (!*obj) PetscFunctionReturn(PETSC_SUCCESS);
956: if (--((PetscObject)*obj)->refct > 0) {
957: *obj = NULL;
958: PetscFunctionReturn(PETSC_SUCCESS);
959: }
960: if ((*obj)->ctxdestroy) PetscCall((*(*obj)->ctxdestroy)(&(*obj)->ctx));
961: else if ((*obj)->userdestroy_deprecated) PetscCall((*(*obj)->userdestroy_deprecated)((*obj)->ctx));
962: PetscCall(PetscHeaderDestroy(obj));
963: PetscFunctionReturn(PETSC_SUCCESS);
964: }
966: /*@C
967: PetscContainerSetCtxDestroy - Sets the destroy function for the data provided to the `PetscContainer` with `PetscContainerSetPointer()`
969: Logically Collective, No Fortran Support
971: Input Parameters:
972: + obj - an object that was created with `PetscContainerCreate()`
973: - des - name of the ctx destroy function, see `PetscCtxDestroyFn` for its calling sequence
975: Level: advanced
977: Note:
978: Use `PetscCtxDestroyDefault()` if the memory was obtained by calling `PetscMalloc()` or one of its variants for single memory allocation.
980: .seealso: `PetscContainerDestroy()`, `PetscContainerUserDestroyDefault()`, `PetscMalloc()`, `PetscMalloc1()`, `PetscCalloc()`, `PetscCalloc1()`, `PetscObject`,
981: `PetscObjectContainerCompose()`, `PetscObjectContainerQuery()`
982: @*/
983: PetscErrorCode PetscContainerSetCtxDestroy(PetscContainer obj, PetscCtxDestroyFn *des)
984: {
985: PetscFunctionBegin;
987: obj->ctxdestroy = des;
988: PetscFunctionReturn(PETSC_SUCCESS);
989: }
991: /*@C
992: PetscContainerSetUserDestroy - Sets the destroy function for the data provided to the `PetscContainer` with `PetscContainerSetPointer()`
994: Logically Collective, No Fortran Support
996: Input Parameters:
997: + obj - an object that was created with `PetscContainerCreate()`
998: - des - name of the ctx destroy function
1000: Level: advanced
1002: Notes:
1003: Deprecated, use `PetscContainerSetCtxDestroy()`
1005: .seealso: `PetscContainerSetCtxDestroy()`, `PetscContainerDestroy()`, `PetscContainerUserDestroyDefault()`, `PetscMalloc()`, `PetscMalloc1()`, `PetscCalloc()`, `PetscCalloc1()`, `PetscObject`,
1006: `PetscObjectContainerCompose()`, `PetscObjectContainerQuery()`
1007: @*/
1008: PetscErrorCode PetscContainerSetUserDestroy(PetscContainer obj, PetscErrorCode (*des)(void *))
1009: {
1010: PetscFunctionBegin;
1012: obj->userdestroy_deprecated = des;
1013: PetscFunctionReturn(PETSC_SUCCESS);
1014: }
1016: PetscClassId PETSC_CONTAINER_CLASSID;
1018: /*@C
1019: PetscContainerCreate - Creates a PETSc object that has room to hold a single pointer.
1021: Collective, No Fortran Support
1023: Input Parameter:
1024: . comm - MPI communicator that shares the object
1026: Output Parameter:
1027: . container - the container created
1029: Level: advanced
1031: Notes:
1032: This allows one to attach any type of data (accessible through a pointer) with the
1033: `PetscObjectCompose()` function to a `PetscObject`. The data item itself is attached by a
1034: call to `PetscContainerSetPointer()`.
1036: .seealso: `PetscContainerDestroy()`, `PetscContainerSetPointer()`, `PetscContainerGetPointer()`, `PetscObjectCompose()`, `PetscObjectQuery()`,
1037: `PetscContainerSetCtxDestroy()`, `PetscObject`, `PetscObjectContainerCompose()`, `PetscObjectContainerQuery()`
1038: @*/
1039: PetscErrorCode PetscContainerCreate(MPI_Comm comm, PetscContainer *container)
1040: {
1041: PetscFunctionBegin;
1042: PetscAssertPointer(container, 2);
1043: PetscCall(PetscSysInitializePackage());
1044: PetscCall(PetscHeaderCreate(*container, PETSC_CONTAINER_CLASSID, "PetscContainer", "Container", "Sys", comm, PetscContainerDestroy, NULL));
1045: PetscFunctionReturn(PETSC_SUCCESS);
1046: }
1048: /*@C
1049: PetscObjectContainerCompose - Creates a `PetscContainer`, provides all of its values and composes it with a `PetscObject`
1051: Collective
1053: Input Parameters:
1054: + obj - the `PetscObject`
1055: . name - the name for the composed container
1056: . pointer - the pointer to the data
1057: - destroy - the routine to destroy the container's data, see `PetscCtxDestroyFn` for its calling sequence; use `PetscCtxDestroyDefault()` if a `PetscFree()` frees the data
1059: Level: advanced
1061: Notes:
1062: This allows one to attach any type of data (accessible through a pointer) with the
1063: `PetscObjectCompose()` function to a `PetscObject`. The data item itself is attached by a
1064: call to `PetscContainerSetPointer()`.
1066: .seealso: `PetscContainerCreate()`, `PetscContainerDestroy()`, `PetscContainerSetPointer()`, `PetscContainerGetPointer()`, `PetscObjectCompose()`, `PetscObjectQuery()`,
1067: `PetscContainerSetCtxDestroy()`, `PetscObject`, `PetscObjectContainerQuery()`
1068: @*/
1069: PetscErrorCode PetscObjectContainerCompose(PetscObject obj, const char *name, void *pointer, PetscCtxDestroyFn *destroy)
1070: {
1071: PetscContainer container;
1073: PetscFunctionBegin;
1074: PetscCall(PetscContainerCreate(PetscObjectComm(obj), &container));
1075: PetscCall(PetscContainerSetPointer(container, pointer));
1076: if (destroy) PetscCall(PetscContainerSetCtxDestroy(container, destroy));
1077: PetscCall(PetscObjectCompose(obj, name, (PetscObject)container));
1078: PetscCall(PetscContainerDestroy(&container));
1079: PetscFunctionReturn(PETSC_SUCCESS);
1080: }
1082: /*@C
1083: PetscObjectContainerQuery - Accesses the pointer in a container composed to a `PetscObject` with `PetscObjectContainerCompose()`
1085: Collective
1087: Input Parameters:
1088: + obj - the `PetscObject`
1089: - name - the name for the composed container
1091: Output Parameter:
1092: . ptr - the pointer to the data
1094: Level: advanced
1096: .seealso: `PetscContainerCreate()`, `PetscContainerDestroy()`, `PetscContainerSetPointer()`, `PetscContainerGetPointer()`, `PetscObjectCompose()`, `PetscObjectQuery()`,
1097: `PetscContainerSetCtxDestroy()`, `PetscObject`, `PetscObjectContainerCompose()`
1098: @*/
1099: PetscErrorCode PetscObjectContainerQuery(PetscObject obj, const char *name, PetscCtxRt ptr)
1100: {
1101: PetscContainer container;
1103: PetscFunctionBegin;
1104: PetscCall(PetscObjectQuery(obj, name, (PetscObject *)&container));
1105: if (container) PetscCall(PetscContainerGetPointer(container, ptr));
1106: else *(void **)ptr = NULL;
1107: PetscFunctionReturn(PETSC_SUCCESS);
1108: }
1110: /*@
1111: PetscObjectSetFromOptions - Sets generic parameters from user options.
1113: Collective
1115: Input Parameter:
1116: . obj - the `PetscObject`
1118: Level: beginner
1120: Note:
1121: We have no generic options at present, so this does nothing.
1123: .seealso: `PetscObjectSetOptionsPrefix()`, `PetscObjectGetOptionsPrefix()`, `PetscObject`
1124: @*/
1125: PetscErrorCode PetscObjectSetFromOptions(PetscObject obj)
1126: {
1127: PetscFunctionBegin;
1129: PetscFunctionReturn(PETSC_SUCCESS);
1130: }
1132: /*@
1133: PetscObjectSetUp - Sets up the internal data structures for later use of the object
1135: Collective
1137: Input Parameter:
1138: . obj - the `PetscObject`
1140: Level: advanced
1142: Note:
1143: This does nothing at present.
1145: .seealso: `PetscObjectDestroy()`, `PetscObject`
1146: @*/
1147: PetscErrorCode PetscObjectSetUp(PetscObject obj)
1148: {
1149: PetscFunctionBegin;
1151: PetscFunctionReturn(PETSC_SUCCESS);
1152: }
1154: /*MC
1155: PetscObjectIsNull - returns true if the given PETSc object is a null object
1157: Fortran only
1159: Synopsis:
1160: #include <petsc/finclude/petscsys.h>
1161: PetscBool PetscObjectIsNull(PetscObject obj)
1163: Logically Collective
1165: Input Parameter:
1166: . obj - the PETSc object
1168: Level: beginner
1170: Example Usage:
1171: .vb
1172: if (PetscObjectIsNull(dm)) then
1173: if (.not. PetscObjectIsNull(dm)) then
1174: .ve
1176: Note:
1177: Code such as
1178: .vb
1179: if (dm == PETSC_NULL_DM) then
1180: .ve
1181: is not allowed.
1183: .seealso: `PetscObject`, `PETSC_NULL_OBJECT`, `PETSC_NULL_VEC`, `PETSC_NULL_VEC_ARRAY`, `PetscObjectNullify()`
1184: M*/
1186: /*MC
1187: PetscObjectNullify - sets a PETSc object, such as `Vec`, back to the state it had when it was declared, so it
1188: can be used in a creation routine, such as `VecCreate()`
1190: Fortran only
1192: Synopsis:
1193: #include <petsc/finclude/petscsys.h>
1194: PetscObjectNullify(PetscObject obj)
1196: Logically Collective
1198: Input Parameter:
1199: . obj - the PETSc object
1201: Level: beginner
1203: Example Usage:
1204: .vb
1205: Vec x, y
1207: VecCreate(PETSC_COMM_WORLD, x, ierr)
1208: ...
1209: y = x
1210: ...
1211: PetscObjectNullify(y)
1212: .ve
1213: You should not call `VecDestroy()` on `y` because that will destroy `x` since the assignment `y = x` does
1214: not increase the reference count of `x`
1216: Note:
1217: Code such as
1218: .vb
1219: y = PETSC_NULL_VEC
1220: .ve
1221: is not allowed.
1223: .seealso: `PetscObject`, `PETSC_NULL_OBJECT`, `PETSC_NULL_VEC`, `PETSC_NULL_VEC_ARRAY`, `PetscObjectIsNull()`
1224: M*/
1226: /*MC
1227: PetscObjectCast - Casts a `PetscObject` to the base `PetscObject` type in function calls
1229: Fortran only
1231: Synopsis:
1232: use petscsys
1234: Level: beginner
1236: Example Usage:
1237: PetscFE fe
1238: .vb
1239: PetscCallA(DMAddField(dm, 0, PetscObjectCast(fe),ierr)
1240: .ve
1242: .seealso: `PetscObject`, `PetscObjectSpecificCast()`
1243: M*/
1245: /*MC
1246: PetscObjectSpecificCast - Casts a `PetscObject` to any specific `PetscObject`
1248: Fortran only
1250: Synopsis:
1251: use petscsys
1253: Level: beginner
1255: Example Usage:
1256: PetscObject obj
1257: PetscFE fe
1258: .vb
1259: PetscCallA(PetscDSGetDiscretization(ds, 0, obj, ierr)
1260: PetscObjectSpecificCast(fe,obj)
1261: .ve
1263: .seealso: `PetscObject`, `PetscObjectCast()`
1264: M*/
1266: /*MC
1267: PetscEnumCase - `case()` statement for a PETSc enum variable or value
1269: Fortran only
1271: Synopsis:
1272: #include <petsc/finclude/petscsys.h>
1273: PetscEnumCase(PetscObject enm)
1275: Input Parameters:
1276: . enum - the PETSc enum value or variable
1278: Level: beginner
1280: Example Usage:
1281: .vb
1282: DMPolytopeType cellType
1283: select PetscEnumCase(cellType)
1284: PetscEnumCase(DM_POLYTOPE_TRIANGLE)
1285: write(*,*) 'cell is a triangle'
1286: PetscEnumCase(DM_POLYTOPE_TETRAHEDRON)
1287: write(*,*) 'cell is a tetrahedron'
1288: case default
1289: write(*,*) 'cell is a something else'
1290: end select
1291: .ve
1292: is equivalent to
1293: .vb
1294: DMPolytopeType cellType
1295: select case(cellType%v)
1296: case(DM_POLYTOPE_TRIANGLE%v)
1297: write(*,*) 'cell is a triangle'
1298: case(DM_POLYTOPE_TETRAHEDRON%v)
1299: write(*,*) 'cell is a tetrahedron'
1300: case default
1301: write(*,*) 'cell is a something else'
1302: end select
1303: .ve
1305: .seealso: `PetscObject`
1306: M*/