Actual source code: dmlocalts.c

  1: #include <petsc/private/dmimpl.h>
  2: #include <petsc/private/tsimpl.h>

  4: typedef struct {
  5:   PetscErrorCode (*boundarylocal)(DM, PetscReal, Vec, Vec, void *);
  6:   PetscErrorCode (*ifunctionlocal)(DM, PetscReal, Vec, Vec, Vec, void *);
  7:   PetscErrorCode (*ijacobianlocal)(DM, PetscReal, Vec, Vec, PetscReal, Mat, Mat, void *);
  8:   PetscErrorCode (*rhsfunctionlocal)(DM, PetscReal, Vec, Vec, void *);
  9:   void *boundarylocalctx;
 10:   void *ifunctionlocalctx;
 11:   void *ijacobianlocalctx;
 12:   void *rhsfunctionlocalctx;
 13:   Vec   lumpedmassinv;
 14:   Mat   mass;
 15:   KSP   kspmass;
 16: } DMTS_Local;

 18: static PetscErrorCode DMTSDestroy_DMLocal(DMTS tdm)
 19: {
 20:   PetscFunctionBegin;
 21:   PetscCall(PetscFree(tdm->data));
 22:   PetscFunctionReturn(PETSC_SUCCESS);
 23: }

 25: static PetscErrorCode DMTSDuplicate_DMLocal(DMTS oldtdm, DMTS tdm)
 26: {
 27:   PetscFunctionBegin;
 28:   PetscCall(PetscNew((DMTS_Local **)&tdm->data));
 29:   if (oldtdm->data) PetscCall(PetscMemcpy(tdm->data, oldtdm->data, sizeof(DMTS_Local)));
 30:   PetscFunctionReturn(PETSC_SUCCESS);
 31: }

 33: static PetscErrorCode DMLocalTSGetContext(DM dm, DMTS tdm, DMTS_Local **dmlocalts)
 34: {
 35:   PetscFunctionBegin;
 36:   *dmlocalts = NULL;
 37:   if (!tdm->data) {
 38:     PetscCall(PetscNew((DMTS_Local **)&tdm->data));

 40:     tdm->ops->destroy   = DMTSDestroy_DMLocal;
 41:     tdm->ops->duplicate = DMTSDuplicate_DMLocal;
 42:   }
 43:   *dmlocalts = (DMTS_Local *)tdm->data;
 44:   PetscFunctionReturn(PETSC_SUCCESS);
 45: }

 47: static PetscErrorCode TSComputeIFunction_DMLocal(TS ts, PetscReal time, Vec X, Vec X_t, Vec F, void *ctx)
 48: {
 49:   DM          dm;
 50:   Vec         locX, locX_t, locF;
 51:   DMTS_Local *dmlocalts = (DMTS_Local *)ctx;

 53:   PetscFunctionBegin;
 58:   PetscCall(TSGetDM(ts, &dm));
 59:   PetscCall(DMGetLocalVector(dm, &locX));
 60:   PetscCall(DMGetLocalVector(dm, &locX_t));
 61:   PetscCall(DMGetLocalVector(dm, &locF));
 62:   PetscCall(VecZeroEntries(locX));
 63:   PetscCall(VecZeroEntries(locX_t));
 64:   if (dmlocalts->boundarylocal) PetscCall((*dmlocalts->boundarylocal)(dm, time, locX, locX_t, dmlocalts->boundarylocalctx));
 65:   PetscCall(DMGlobalToLocalBegin(dm, X, INSERT_VALUES, locX));
 66:   PetscCall(DMGlobalToLocalEnd(dm, X, INSERT_VALUES, locX));
 67:   PetscCall(DMGlobalToLocalBegin(dm, X_t, INSERT_VALUES, locX_t));
 68:   PetscCall(DMGlobalToLocalEnd(dm, X_t, INSERT_VALUES, locX_t));
 69:   PetscCall(VecZeroEntries(locF));
 70:   CHKMEMQ;
 71:   PetscCall((*dmlocalts->ifunctionlocal)(dm, time, locX, locX_t, locF, dmlocalts->ifunctionlocalctx));
 72:   CHKMEMQ;
 73:   PetscCall(VecZeroEntries(F));
 74:   PetscCall(DMLocalToGlobalBegin(dm, locF, ADD_VALUES, F));
 75:   PetscCall(DMLocalToGlobalEnd(dm, locF, ADD_VALUES, F));
 76:   PetscCall(DMRestoreLocalVector(dm, &locX));
 77:   PetscCall(DMRestoreLocalVector(dm, &locX_t));
 78:   PetscCall(DMRestoreLocalVector(dm, &locF));
 79:   PetscFunctionReturn(PETSC_SUCCESS);
 80: }

 82: static PetscErrorCode TSComputeRHSFunction_DMLocal(TS ts, PetscReal time, Vec X, Vec F, void *ctx)
 83: {
 84:   DM          dm;
 85:   Vec         locX, locF;
 86:   DMTS_Local *dmlocalts = (DMTS_Local *)ctx;

 88:   PetscFunctionBegin;
 92:   PetscCall(TSGetDM(ts, &dm));
 93:   PetscCall(DMGetLocalVector(dm, &locX));
 94:   PetscCall(DMGetLocalVector(dm, &locF));
 95:   PetscCall(VecZeroEntries(locX));
 96:   if (dmlocalts->boundarylocal) PetscCall((*dmlocalts->boundarylocal)(dm, time, locX, NULL, dmlocalts->boundarylocalctx));
 97:   PetscCall(DMGlobalToLocalBegin(dm, X, INSERT_VALUES, locX));
 98:   PetscCall(DMGlobalToLocalEnd(dm, X, INSERT_VALUES, locX));
 99:   PetscCall(VecZeroEntries(locF));
100:   CHKMEMQ;
101:   PetscCall((*dmlocalts->rhsfunctionlocal)(dm, time, locX, locF, dmlocalts->rhsfunctionlocalctx));
102:   CHKMEMQ;
103:   PetscCall(VecZeroEntries(F));
104:   PetscCall(DMLocalToGlobalBegin(dm, locF, ADD_VALUES, F));
105:   PetscCall(DMLocalToGlobalEnd(dm, locF, ADD_VALUES, F));
106:   if (dmlocalts->lumpedmassinv) {
107:     PetscCall(VecPointwiseMult(F, dmlocalts->lumpedmassinv, F));
108:   } else if (dmlocalts->kspmass) {
109:     Vec tmp;

111:     PetscCall(DMGetGlobalVector(dm, &tmp));
112:     PetscCall(KSPSolve(dmlocalts->kspmass, F, tmp));
113:     PetscCall(VecCopy(tmp, F));
114:     PetscCall(DMRestoreGlobalVector(dm, &tmp));
115:   }
116:   PetscCall(DMRestoreLocalVector(dm, &locX));
117:   PetscCall(DMRestoreLocalVector(dm, &locF));
118:   PetscFunctionReturn(PETSC_SUCCESS);
119: }

121: static PetscErrorCode TSComputeIJacobian_DMLocal(TS ts, PetscReal time, Vec X, Vec X_t, PetscReal a, Mat A, Mat B, void *ctx)
122: {
123:   DM          dm;
124:   Vec         locX, locX_t;
125:   DMTS_Local *dmlocalts = (DMTS_Local *)ctx;

127:   PetscFunctionBegin;
128:   PetscCall(TSGetDM(ts, &dm));
129:   if (dmlocalts->ijacobianlocal) {
130:     PetscCall(DMGetLocalVector(dm, &locX));
131:     PetscCall(DMGetLocalVector(dm, &locX_t));
132:     PetscCall(VecZeroEntries(locX));
133:     PetscCall(VecZeroEntries(locX_t));
134:     if (dmlocalts->boundarylocal) PetscCall((*dmlocalts->boundarylocal)(dm, time, locX, locX_t, dmlocalts->boundarylocalctx));
135:     PetscCall(DMGlobalToLocalBegin(dm, X, INSERT_VALUES, locX));
136:     PetscCall(DMGlobalToLocalEnd(dm, X, INSERT_VALUES, locX));
137:     PetscCall(DMGlobalToLocalBegin(dm, X_t, INSERT_VALUES, locX_t));
138:     PetscCall(DMGlobalToLocalEnd(dm, X_t, INSERT_VALUES, locX_t));
139:     CHKMEMQ;
140:     PetscCall((*dmlocalts->ijacobianlocal)(dm, time, locX, locX_t, a, A, B, dmlocalts->ijacobianlocalctx));
141:     CHKMEMQ;
142:     PetscCall(DMRestoreLocalVector(dm, &locX));
143:     PetscCall(DMRestoreLocalVector(dm, &locX_t));
144:   } else {
145:     MatFDColoring fdcoloring;
146:     PetscCall(PetscObjectQuery((PetscObject)dm, "DMDASNES_FDCOLORING", (PetscObject *)&fdcoloring));
147:     if (!fdcoloring) {
148:       ISColoring coloring;

150:       PetscCall(DMCreateColoring(dm, dm->coloringtype, &coloring));
151:       PetscCall(MatFDColoringCreate(B, coloring, &fdcoloring));
152:       PetscCall(ISColoringDestroy(&coloring));
153:       switch (dm->coloringtype) {
154:       case IS_COLORING_GLOBAL:
155:         PetscCall(MatFDColoringSetFunction(fdcoloring, (PetscErrorCode (*)(void))TSComputeIFunction_DMLocal, dmlocalts));
156:         break;
157:       default:
158:         SETERRQ(PetscObjectComm((PetscObject)ts), PETSC_ERR_SUP, "No support for coloring type '%s'", ISColoringTypes[dm->coloringtype]);
159:       }
160:       PetscCall(PetscObjectSetOptionsPrefix((PetscObject)fdcoloring, ((PetscObject)dm)->prefix));
161:       PetscCall(MatFDColoringSetFromOptions(fdcoloring));
162:       PetscCall(MatFDColoringSetUp(B, coloring, fdcoloring));
163:       PetscCall(PetscObjectCompose((PetscObject)dm, "DMDASNES_FDCOLORING", (PetscObject)fdcoloring));
164:       PetscCall(PetscObjectDereference((PetscObject)fdcoloring));

166:       /* The following breaks an ugly reference counting loop that deserves a paragraph. MatFDColoringApply() will call
167:        * VecDuplicate() with the state Vec and store inside the MatFDColoring. This Vec will duplicate the Vec, but the
168:        * MatFDColoring is composed with the DM. We dereference the DM here so that the reference count will eventually
169:        * drop to 0. Note the code in DMDestroy() that exits early for a negative reference count. That code path will be
170:        * taken when the PetscObjectList for the Vec inside MatFDColoring is destroyed.
171:        */
172:       PetscCall(PetscObjectDereference((PetscObject)dm));
173:     }
174:     PetscCall(MatFDColoringApply(B, fdcoloring, X, ts));
175:   }
176:   /* This will be redundant if the user called both, but it's too common to forget. */
177:   if (A != B) {
178:     PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
179:     PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));
180:   }
181:   PetscFunctionReturn(PETSC_SUCCESS);
182: }

184: /*@C
185:   DMTSSetBoundaryLocal - set the function for essential boundary data for a local implicit function evaluation.

187:   Logically Collective

189:   Input Parameters:
190: + dm   - `DM` to associate callback with
191: . func - local function evaluation
192: - ctx  - context for function evaluation

194:   Level: intermediate

196:   Notes:
197:   `func` should set the essential boundary data for the local portion of the solution, as
198:   well its time derivative (if it is not `NULL`).

200:   Vectors are initialized to zero before this function, so it is only needed for non
201:   homogeneous data.

203:   This function is somewhat optional: boundary data could potentially be inserted by a function
204:   passed to `DMTSSetIFunctionLocal()`. The use case for this function is for discretizations
205:   with constraints (see `DMGetDefaultConstraints()`): this function inserts boundary values
206:   before constraint interpolation.

208: .seealso: [](ch_ts), `DM`, `TS`, `DMTSSetIFunction()`, `DMTSSetIJacobianLocal()`
209: @*/
210: PetscErrorCode DMTSSetBoundaryLocal(DM dm, PetscErrorCode (*func)(DM, PetscReal, Vec, Vec, void *), void *ctx)
211: {
212:   DMTS        tdm;
213:   DMTS_Local *dmlocalts;

215:   PetscFunctionBegin;
217:   PetscCall(DMGetDMTSWrite(dm, &tdm));
218:   PetscCall(DMLocalTSGetContext(dm, tdm, &dmlocalts));

220:   dmlocalts->boundarylocal    = func;
221:   dmlocalts->boundarylocalctx = ctx;
222:   PetscFunctionReturn(PETSC_SUCCESS);
223: }

225: /*@C
226:   DMTSGetIFunctionLocal - get the local implicit function evaluation function. This function is called with local vector
227:   containing the local vector information PLUS ghost point information. It should compute a result for all local
228:   elements and `DM` will automatically accumulate the overlapping values.

230:   Logically Collective

232:   Input Parameter:
233: . dm - `DM` to associate callback with

235:   Output Parameters:
236: + func - local function evaluation
237: - ctx  - context for function evaluation

239:   Level: beginner

241: .seealso: [](ch_ts), `DM`, `DMTSSetIFunctionLocal()`, `DMTSSetIFunction()`, `DMTSSetIJacobianLocal()`
242: @*/
243: PetscErrorCode DMTSGetIFunctionLocal(DM dm, PetscErrorCode (**func)(DM, PetscReal, Vec, Vec, Vec, void *), void **ctx)
244: {
245:   DMTS        tdm;
246:   DMTS_Local *dmlocalts;

248:   PetscFunctionBegin;
250:   PetscCall(DMGetDMTS(dm, &tdm));
251:   PetscCall(DMLocalTSGetContext(dm, tdm, &dmlocalts));
252:   if (func) {
253:     PetscAssertPointer(func, 2);
254:     *func = dmlocalts->ifunctionlocal;
255:   }
256:   if (ctx) {
257:     PetscAssertPointer(ctx, 3);
258:     *ctx = dmlocalts->ifunctionlocalctx;
259:   }
260:   PetscFunctionReturn(PETSC_SUCCESS);
261: }

263: /*@C
264:   DMTSSetIFunctionLocal - set a local implicit function evaluation function. This function is called with local vector
265:   containing the local vector information PLUS ghost point information. It should compute a result for all local
266:   elements and `DM` will automatically accumulate the overlapping values.

268:   Logically Collective

270:   Input Parameters:
271: + dm   - `DM` to associate callback with
272: . func - local function evaluation
273: - ctx  - context for function evaluation

275:   Level: beginner

277: .seealso: [](ch_ts), `DM`, `DMTSGetIFunctionLocal()`, `DMTSSetIFunction()`, `DMTSSetIJacobianLocal()`
278: @*/
279: PetscErrorCode DMTSSetIFunctionLocal(DM dm, PetscErrorCode (*func)(DM, PetscReal, Vec, Vec, Vec, void *), void *ctx)
280: {
281:   DMTS        tdm;
282:   DMTS_Local *dmlocalts;

284:   PetscFunctionBegin;
286:   PetscCall(DMGetDMTSWrite(dm, &tdm));
287:   PetscCall(DMLocalTSGetContext(dm, tdm, &dmlocalts));

289:   dmlocalts->ifunctionlocal    = func;
290:   dmlocalts->ifunctionlocalctx = ctx;

292:   PetscCall(DMTSSetIFunction(dm, TSComputeIFunction_DMLocal, dmlocalts));
293:   if (!tdm->ops->ijacobian) { /* Call us for the Jacobian too, can be overridden by the user. */
294:     PetscCall(DMTSSetIJacobian(dm, TSComputeIJacobian_DMLocal, dmlocalts));
295:   }
296:   PetscFunctionReturn(PETSC_SUCCESS);
297: }

299: /*@C
300:   DMTSGetIJacobianLocal - get a local Jacobian evaluation function

302:   Logically Collective

304:   Input Parameter:
305: . dm - `DM` to associate callback with

307:   Output Parameters:
308: + func - local Jacobian evaluation
309: - ctx  - optional context for local Jacobian evaluation

311:   Level: beginner

313: .seealso: [](ch_ts), `DM`, `DMTSSetIJacobianLocal()`, `DMTSSetIFunctionLocal()`, `DMTSSetIJacobian()`, `DMTSSetIFunction()`
314: @*/
315: PetscErrorCode DMTSGetIJacobianLocal(DM dm, PetscErrorCode (**func)(DM, PetscReal, Vec, Vec, PetscReal, Mat, Mat, void *), void **ctx)
316: {
317:   DMTS        tdm;
318:   DMTS_Local *dmlocalts;

320:   PetscFunctionBegin;
322:   PetscCall(DMGetDMTS(dm, &tdm));
323:   PetscCall(DMLocalTSGetContext(dm, tdm, &dmlocalts));
324:   if (func) {
325:     PetscAssertPointer(func, 2);
326:     *func = dmlocalts->ijacobianlocal;
327:   }
328:   if (ctx) {
329:     PetscAssertPointer(ctx, 3);
330:     *ctx = dmlocalts->ijacobianlocalctx;
331:   }
332:   PetscFunctionReturn(PETSC_SUCCESS);
333: }

335: /*@C
336:   DMTSSetIJacobianLocal - set a local Jacobian evaluation function

338:   Logically Collective

340:   Input Parameters:
341: + dm   - `DM` to associate callback with
342: . func - local Jacobian evaluation
343: - ctx  - optional context for local Jacobian evaluation

345:   Level: beginner

347: .seealso: [](ch_ts), `DM`, `DMTSGetIJacobianLocal()`, `DMTSSetIFunctionLocal()`, `DMTSSetIJacobian()`, `DMTSSetIFunction()`
348: @*/
349: PetscErrorCode DMTSSetIJacobianLocal(DM dm, PetscErrorCode (*func)(DM, PetscReal, Vec, Vec, PetscReal, Mat, Mat, void *), void *ctx)
350: {
351:   DMTS        tdm;
352:   DMTS_Local *dmlocalts;

354:   PetscFunctionBegin;
356:   PetscCall(DMGetDMTSWrite(dm, &tdm));
357:   PetscCall(DMLocalTSGetContext(dm, tdm, &dmlocalts));

359:   dmlocalts->ijacobianlocal    = func;
360:   dmlocalts->ijacobianlocalctx = ctx;

362:   PetscCall(DMTSSetIJacobian(dm, TSComputeIJacobian_DMLocal, dmlocalts));
363:   PetscFunctionReturn(PETSC_SUCCESS);
364: }

366: /*@C
367:   DMTSGetRHSFunctionLocal - get a local rhs function evaluation function. This function is called with local vector
368:   containing the local vector information PLUS ghost point information. It should compute a result for all local
369:   elements and `DM` will automatically accumulate the overlapping values.

371:   Logically Collective

373:   Input Parameter:
374: . dm - `DM` to associate callback with

376:   Output Parameters:
377: + func - local function evaluation
378: - ctx  - context for function evaluation

380:   Level: beginner

382: .seealso: [](ch_ts), `DM`, `DMTSSetRHSFunctionLocal()`, `DMTSSetRHSFunction()`, `DMTSSetIFunction()`, `DMTSSetIJacobianLocal()`
383: @*/
384: PetscErrorCode DMTSGetRHSFunctionLocal(DM dm, PetscErrorCode (**func)(DM, PetscReal, Vec, Vec, void *), void **ctx)
385: {
386:   DMTS        tdm;
387:   DMTS_Local *dmlocalts;

389:   PetscFunctionBegin;
391:   PetscCall(DMGetDMTS(dm, &tdm));
392:   PetscCall(DMLocalTSGetContext(dm, tdm, &dmlocalts));
393:   if (func) {
394:     PetscAssertPointer(func, 2);
395:     *func = dmlocalts->rhsfunctionlocal;
396:   }
397:   if (ctx) {
398:     PetscAssertPointer(ctx, 3);
399:     *ctx = dmlocalts->rhsfunctionlocalctx;
400:   }
401:   PetscFunctionReturn(PETSC_SUCCESS);
402: }

404: /*@C
405:   DMTSSetRHSFunctionLocal - set a local rhs function evaluation function. This function is called with local vector
406:   containing the local vector information PLUS ghost point information. It should compute a result for all local
407:   elements and `DM` will automatically accumulate the overlapping values.

409:   Logically Collective

411:   Input Parameters:
412: + dm   - `DM` to associate callback with
413: . func - local function evaluation
414: - ctx  - context for function evaluation

416:   Level: beginner

418: .seealso: [](ch_ts), `DM`, `DMTSGetRHSFunctionLocal()`, `DMTSSetRHSFunction()`, `DMTSSetIFunction()`, `DMTSSetIJacobianLocal()`
419: @*/
420: PetscErrorCode DMTSSetRHSFunctionLocal(DM dm, PetscErrorCode (*func)(DM, PetscReal, Vec, Vec, void *), void *ctx)
421: {
422:   DMTS        tdm;
423:   DMTS_Local *dmlocalts;

425:   PetscFunctionBegin;
427:   PetscCall(DMGetDMTSWrite(dm, &tdm));
428:   PetscCall(DMLocalTSGetContext(dm, tdm, &dmlocalts));

430:   dmlocalts->rhsfunctionlocal    = func;
431:   dmlocalts->rhsfunctionlocalctx = ctx;

433:   PetscCall(DMTSSetRHSFunction(dm, TSComputeRHSFunction_DMLocal, dmlocalts));
434:   PetscFunctionReturn(PETSC_SUCCESS);
435: }

437: /*@
438:   DMTSCreateRHSMassMatrix - This creates the mass matrix associated with the given `DM`, and a solver to invert it, and stores them in the `DM` context.

440:   Collective

442:   Input Parameter:
443: . dm - `DM` providing the mass matrix

445:   Level: developer

447:   Note:
448:   The idea here is that an explicit system can be given a mass matrix, based on the `DM`, which is inverted on the RHS at each step.

450: .seealso: [](ch_ts), `DM`, `DMTSCreateRHSMassMatrixLumped()`, `DMTSDestroyRHSMassMatrix()`, `DMCreateMassMatrix()`, `DMTS`
451: @*/
452: PetscErrorCode DMTSCreateRHSMassMatrix(DM dm)
453: {
454:   DMTS        tdm;
455:   DMTS_Local *dmlocalts;
456:   const char *prefix;

458:   PetscFunctionBegin;
460:   PetscCall(DMGetDMTSWrite(dm, &tdm));
461:   PetscCall(DMLocalTSGetContext(dm, tdm, &dmlocalts));
462:   PetscCall(DMCreateMassMatrix(dm, dm, &dmlocalts->mass));
463:   PetscCall(KSPCreate(PetscObjectComm((PetscObject)dm), &dmlocalts->kspmass));
464:   PetscCall(PetscObjectGetOptionsPrefix((PetscObject)dm, &prefix));
465:   PetscCall(KSPSetOptionsPrefix(dmlocalts->kspmass, prefix));
466:   PetscCall(KSPAppendOptionsPrefix(dmlocalts->kspmass, "mass_"));
467:   PetscCall(KSPSetFromOptions(dmlocalts->kspmass));
468:   PetscCall(KSPSetOperators(dmlocalts->kspmass, dmlocalts->mass, dmlocalts->mass));
469:   PetscFunctionReturn(PETSC_SUCCESS);
470: }

472: /*@
473:   DMTSCreateRHSMassMatrixLumped - This creates the lumped mass matrix associated with the given `DM`, and a solver to invert it, and stores them in the `DM` context.

475:   Collective

477:   Input Parameter:
478: . dm - `DM` providing the mass matrix

480:   Level: developer

482:   Note:
483:   The idea here is that an explicit system can be given a mass matrix, based on the `DM`, which is inverted on the RHS at each step.
484:   Since the matrix is lumped, inversion is trivial.

486: .seealso: [](ch_ts), `DM`, `DMTSCreateRHSMassMatrix()`, `DMTSDestroyRHSMassMatrix()`, `DMCreateMassMatrix()`, `DMTS`
487: @*/
488: PetscErrorCode DMTSCreateRHSMassMatrixLumped(DM dm)
489: {
490:   DMTS        tdm;
491:   DMTS_Local *dmlocalts;

493:   PetscFunctionBegin;
495:   PetscCall(DMGetDMTSWrite(dm, &tdm));
496:   PetscCall(DMLocalTSGetContext(dm, tdm, &dmlocalts));
497:   PetscCall(DMCreateMassMatrixLumped(dm, NULL, &dmlocalts->lumpedmassinv));
498:   PetscCall(VecReciprocal(dmlocalts->lumpedmassinv));
499:   PetscCall(VecViewFromOptions(dmlocalts->lumpedmassinv, NULL, "-lumped_mass_inv_view"));
500:   PetscFunctionReturn(PETSC_SUCCESS);
501: }

503: /*@
504:   DMTSDestroyRHSMassMatrix - Destroys the mass matrix and solver stored in the `DM` context, if they exist.

506:   Logically Collective

508:   Input Parameter:
509: . dm - `DM` providing the mass matrix

511:   Level: developer

513: .seealso: [](ch_ts), `DM`, `DMTSCreateRHSMassMatrixLumped()`, `DMCreateMassMatrix()`, `DMTS`
514: @*/
515: PetscErrorCode DMTSDestroyRHSMassMatrix(DM dm)
516: {
517:   DMTS        tdm;
518:   DMTS_Local *dmlocalts;

520:   PetscFunctionBegin;
522:   PetscCall(DMGetDMTSWrite(dm, &tdm));
523:   PetscCall(DMLocalTSGetContext(dm, tdm, &dmlocalts));
524:   PetscCall(VecDestroy(&dmlocalts->lumpedmassinv));
525:   PetscCall(MatDestroy(&dmlocalts->mass));
526:   PetscCall(KSPDestroy(&dmlocalts->kspmass));
527:   PetscFunctionReturn(PETSC_SUCCESS);
528: }