xref: /petsc/src/ts/utils/dmplexts.c (revision 8fb5bd83c3955fefcf33a54e3bb66920a9fa884b)
1 #include <petsc/private/dmpleximpl.h> /*I "petscdmplex.h" I*/
2 #include <petsc/private/tsimpl.h>     /*I "petscts.h" I*/
3 #include <petsc/private/snesimpl.h>
4 #include <petscds.h>
5 #include <petscfv.h>
6 
7 static PetscErrorCode DMTSConvertPlex(DM dm, DM *plex, PetscBool copy)
8 {
9   PetscBool      isPlex;
10 
11   PetscFunctionBegin;
12   PetscCall(PetscObjectTypeCompare((PetscObject) dm, DMPLEX, &isPlex));
13   if (isPlex) {
14     *plex = dm;
15     PetscCall(PetscObjectReference((PetscObject) dm));
16   } else {
17     PetscCall(PetscObjectQuery((PetscObject) dm, "dm_plex", (PetscObject *) plex));
18     if (!*plex) {
19       PetscCall(DMConvert(dm,DMPLEX,plex));
20       PetscCall(PetscObjectCompose((PetscObject) dm, "dm_plex", (PetscObject) *plex));
21       if (copy) {
22         PetscCall(DMCopyDMTS(dm, *plex));
23         PetscCall(DMCopyDMSNES(dm, *plex));
24         PetscCall(DMCopyAuxiliaryVec(dm, *plex));
25       }
26     } else {
27       PetscCall(PetscObjectReference((PetscObject) *plex));
28     }
29   }
30   PetscFunctionReturn(0);
31 }
32 
33 /*@
34   DMPlexTSComputeRHSFunctionFVM - Form the local forcing F from the local input X using pointwise functions specified by the user
35 
36   Input Parameters:
37 + dm - The mesh
38 . t - The time
39 . locX  - Local solution
40 - user - The user context
41 
42   Output Parameter:
43 . F  - Global output vector
44 
45   Level: developer
46 
47 .seealso: `DMPlexComputeJacobianActionFEM()`
48 @*/
49 PetscErrorCode DMPlexTSComputeRHSFunctionFVM(DM dm, PetscReal time, Vec locX, Vec F, void *user)
50 {
51   Vec          locF;
52   IS           cellIS;
53   DM           plex;
54   PetscInt     depth;
55   PetscFormKey key = {NULL, 0, 0, 0};
56 
57   PetscFunctionBegin;
58   PetscCall(DMTSConvertPlex(dm,&plex,PETSC_TRUE));
59   PetscCall(DMPlexGetDepth(plex, &depth));
60   PetscCall(DMGetStratumIS(plex, "dim", depth, &cellIS));
61   if (!cellIS) PetscCall(DMGetStratumIS(plex, "depth", depth, &cellIS));
62   PetscCall(DMGetLocalVector(plex, &locF));
63   PetscCall(VecZeroEntries(locF));
64   PetscCall(DMPlexComputeResidual_Internal(plex, key, cellIS, time, locX, NULL, time, locF, user));
65   PetscCall(DMLocalToGlobalBegin(plex, locF, ADD_VALUES, F));
66   PetscCall(DMLocalToGlobalEnd(plex, locF, ADD_VALUES, F));
67   PetscCall(DMRestoreLocalVector(plex, &locF));
68   PetscCall(ISDestroy(&cellIS));
69   PetscCall(DMDestroy(&plex));
70   PetscFunctionReturn(0);
71 }
72 
73 /*@
74   DMPlexTSComputeBoundary - Insert the essential boundary values for the local input X and/or its time derivative X_t using pointwise functions specified by the user
75 
76   Input Parameters:
77 + dm - The mesh
78 . t - The time
79 . locX  - Local solution
80 . locX_t - Local solution time derivative, or NULL
81 - user - The user context
82 
83   Level: developer
84 
85 .seealso: `DMPlexComputeJacobianActionFEM()`
86 @*/
87 PetscErrorCode DMPlexTSComputeBoundary(DM dm, PetscReal time, Vec locX, Vec locX_t, void *user)
88 {
89   DM             plex;
90   Vec            faceGeometryFVM = NULL;
91   PetscInt       Nf, f;
92 
93   PetscFunctionBegin;
94   PetscCall(DMTSConvertPlex(dm, &plex, PETSC_TRUE));
95   PetscCall(DMGetNumFields(plex, &Nf));
96   if (!locX_t) {
97     /* This is the RHS part */
98     for (f = 0; f < Nf; f++) {
99       PetscObject  obj;
100       PetscClassId id;
101 
102       PetscCall(DMGetField(plex, f, NULL, &obj));
103       PetscCall(PetscObjectGetClassId(obj, &id));
104       if (id == PETSCFV_CLASSID) {
105         PetscCall(DMPlexGetGeometryFVM(plex, &faceGeometryFVM, NULL, NULL));
106         break;
107       }
108     }
109   }
110   PetscCall(DMPlexInsertBoundaryValues(plex, PETSC_TRUE, locX, time, faceGeometryFVM, NULL, NULL));
111   PetscCall(DMPlexInsertTimeDerivativeBoundaryValues(plex, PETSC_TRUE, locX_t, time, faceGeometryFVM, NULL, NULL));
112   PetscCall(DMDestroy(&plex));
113   PetscFunctionReturn(0);
114 }
115 
116 /*@
117   DMPlexTSComputeIFunctionFEM - Form the local residual F from the local input X using pointwise functions specified by the user
118 
119   Input Parameters:
120 + dm - The mesh
121 . t - The time
122 . locX  - Local solution
123 . locX_t - Local solution time derivative, or NULL
124 - user - The user context
125 
126   Output Parameter:
127 . locF  - Local output vector
128 
129   Level: developer
130 
131 .seealso: `DMPlexTSComputeIFunctionFEM()`, `DMPlexTSComputeRHSFunctionFEM()`
132 @*/
133 PetscErrorCode DMPlexTSComputeIFunctionFEM(DM dm, PetscReal time, Vec locX, Vec locX_t, Vec locF, void *user)
134 {
135   DM             plex;
136   IS             allcellIS;
137   PetscInt       Nds, s;
138 
139   PetscFunctionBegin;
140   PetscCall(DMTSConvertPlex(dm, &plex, PETSC_TRUE));
141   PetscCall(DMPlexGetAllCells_Internal(plex, &allcellIS));
142   PetscCall(DMGetNumDS(dm, &Nds));
143   for (s = 0; s < Nds; ++s) {
144     PetscDS          ds;
145     IS               cellIS;
146     PetscFormKey key;
147 
148     PetscCall(DMGetRegionNumDS(dm, s, &key.label, NULL, &ds));
149     key.value = 0;
150     key.field = 0;
151     key.part  = 0;
152     if (!key.label) {
153       PetscCall(PetscObjectReference((PetscObject) allcellIS));
154       cellIS = allcellIS;
155     } else {
156       IS pointIS;
157 
158       key.value = 1;
159       PetscCall(DMLabelGetStratumIS(key.label, key.value, &pointIS));
160       PetscCall(ISIntersect_Caching_Internal(allcellIS, pointIS, &cellIS));
161       PetscCall(ISDestroy(&pointIS));
162     }
163     PetscCall(DMPlexComputeResidual_Internal(plex, key, cellIS, time, locX, locX_t, time, locF, user));
164     PetscCall(ISDestroy(&cellIS));
165   }
166   PetscCall(ISDestroy(&allcellIS));
167   PetscCall(DMDestroy(&plex));
168   PetscFunctionReturn(0);
169 }
170 
171 /*@
172   DMPlexTSComputeIJacobianFEM - Form the local Jacobian J from the local input X using pointwise functions specified by the user
173 
174   Input Parameters:
175 + dm - The mesh
176 . t - The time
177 . locX  - Local solution
178 . locX_t - Local solution time derivative, or NULL
179 . X_tshift - The multiplicative parameter for dF/du_t
180 - user - The user context
181 
182   Output Parameter:
183 . locF  - Local output vector
184 
185   Level: developer
186 
187 .seealso: `DMPlexTSComputeIFunctionFEM()`, `DMPlexTSComputeRHSFunctionFEM()`
188 @*/
189 PetscErrorCode DMPlexTSComputeIJacobianFEM(DM dm, PetscReal time, Vec locX, Vec locX_t, PetscReal X_tShift, Mat Jac, Mat JacP, void *user)
190 {
191   DM             plex;
192   IS             allcellIS;
193   PetscBool      hasJac, hasPrec;
194   PetscInt       Nds, s;
195 
196   PetscFunctionBegin;
197   PetscCall(DMTSConvertPlex(dm, &plex, PETSC_TRUE));
198   PetscCall(DMPlexGetAllCells_Internal(plex, &allcellIS));
199   PetscCall(DMGetNumDS(dm, &Nds));
200   for (s = 0; s < Nds; ++s) {
201     PetscDS          ds;
202     IS               cellIS;
203     PetscFormKey key;
204 
205     PetscCall(DMGetRegionNumDS(dm, s, &key.label, NULL, &ds));
206     key.value = 0;
207     key.field = 0;
208     key.part  = 0;
209     if (!key.label) {
210       PetscCall(PetscObjectReference((PetscObject) allcellIS));
211       cellIS = allcellIS;
212     } else {
213       IS pointIS;
214 
215       key.value = 1;
216       PetscCall(DMLabelGetStratumIS(key.label, key.value, &pointIS));
217       PetscCall(ISIntersect_Caching_Internal(allcellIS, pointIS, &cellIS));
218       PetscCall(ISDestroy(&pointIS));
219     }
220     if (!s) {
221       PetscCall(PetscDSHasJacobian(ds, &hasJac));
222       PetscCall(PetscDSHasJacobianPreconditioner(ds, &hasPrec));
223       if (hasJac && hasPrec) PetscCall(MatZeroEntries(Jac));
224       PetscCall(MatZeroEntries(JacP));
225     }
226     PetscCall(DMPlexComputeJacobian_Internal(plex, key, cellIS, time, X_tShift, locX, locX_t, Jac, JacP, user));
227     PetscCall(ISDestroy(&cellIS));
228   }
229   PetscCall(ISDestroy(&allcellIS));
230   PetscCall(DMDestroy(&plex));
231   PetscFunctionReturn(0);
232 }
233 
234 /*@
235   DMPlexTSComputeRHSFunctionFEM - Form the local residual G from the local input X using pointwise functions specified by the user
236 
237   Input Parameters:
238 + dm - The mesh
239 . t - The time
240 . locX  - Local solution
241 - user - The user context
242 
243   Output Parameter:
244 . locG  - Local output vector
245 
246   Level: developer
247 
248 .seealso: `DMPlexTSComputeIFunctionFEM()`, `DMPlexTSComputeIJacobianFEM()`
249 @*/
250 PetscErrorCode DMPlexTSComputeRHSFunctionFEM(DM dm, PetscReal time, Vec locX, Vec locG, void *user)
251 {
252   DM             plex;
253   IS             allcellIS;
254   PetscInt       Nds, s;
255 
256   PetscFunctionBegin;
257   PetscCall(DMTSConvertPlex(dm, &plex, PETSC_TRUE));
258   PetscCall(DMPlexGetAllCells_Internal(plex, &allcellIS));
259   PetscCall(DMGetNumDS(dm, &Nds));
260   for (s = 0; s < Nds; ++s) {
261     PetscDS          ds;
262     IS               cellIS;
263     PetscFormKey key;
264 
265     PetscCall(DMGetRegionNumDS(dm, s, &key.label, NULL, &ds));
266     key.value = 0;
267     key.field = 0;
268     key.part  = 100;
269     if (!key.label) {
270       PetscCall(PetscObjectReference((PetscObject) allcellIS));
271       cellIS = allcellIS;
272     } else {
273       IS pointIS;
274 
275       key.value = 1;
276       PetscCall(DMLabelGetStratumIS(key.label, key.value, &pointIS));
277       PetscCall(ISIntersect_Caching_Internal(allcellIS, pointIS, &cellIS));
278       PetscCall(ISDestroy(&pointIS));
279     }
280     PetscCall(DMPlexComputeResidual_Internal(plex, key, cellIS, time, locX, NULL, time, locG, user));
281     PetscCall(ISDestroy(&cellIS));
282   }
283   PetscCall(ISDestroy(&allcellIS));
284   PetscCall(DMDestroy(&plex));
285   PetscFunctionReturn(0);
286 }
287 
288 /*@C
289   DMTSCheckResidual - Check the residual of the exact solution
290 
291   Input Parameters:
292 + ts  - the TS object
293 . dm  - the DM
294 . t   - the time
295 . u   - a DM vector
296 . u_t - a DM vector
297 - tol - A tolerance for the check, or -1 to print the results instead
298 
299   Output Parameters:
300 . residual - The residual norm of the exact solution, or NULL
301 
302   Level: developer
303 
304 .seealso: `DNTSCheckFromOptions()`, `DMTSCheckJacobian()`, `DNSNESCheckFromOptions()`, `DMSNESCheckDiscretization()`, `DMSNESCheckJacobian()`
305 @*/
306 PetscErrorCode DMTSCheckResidual(TS ts, DM dm, PetscReal t, Vec u, Vec u_t, PetscReal tol, PetscReal *residual)
307 {
308   MPI_Comm       comm;
309   Vec            r;
310   PetscReal      res;
311 
312   PetscFunctionBegin;
313   PetscValidHeaderSpecific(ts, TS_CLASSID, 1);
314   PetscValidHeaderSpecific(dm, DM_CLASSID, 2);
315   PetscValidHeaderSpecific(u, VEC_CLASSID, 4);
316   if (residual) PetscValidRealPointer(residual, 7);
317   PetscCall(PetscObjectGetComm((PetscObject) ts, &comm));
318   PetscCall(DMComputeExactSolution(dm, t, u, u_t));
319   PetscCall(VecDuplicate(u, &r));
320   PetscCall(TSComputeIFunction(ts, t, u, u_t, r, PETSC_FALSE));
321   PetscCall(VecNorm(r, NORM_2, &res));
322   if (tol >= 0.0) {
323     PetscCheck(res <= tol,comm, PETSC_ERR_ARG_WRONG, "L_2 Residual %g exceeds tolerance %g", (double) res, (double) tol);
324   } else if (residual) {
325     *residual = res;
326   } else {
327     PetscCall(PetscPrintf(comm, "L_2 Residual: %g\n", (double)res));
328     PetscCall(VecChop(r, 1.0e-10));
329     PetscCall(PetscObjectCompose((PetscObject) r, "__Vec_bc_zero__", (PetscObject) dm));
330     PetscCall(PetscObjectSetName((PetscObject) r, "Initial Residual"));
331     PetscCall(PetscObjectSetOptionsPrefix((PetscObject)r,"res_"));
332     PetscCall(VecViewFromOptions(r, NULL, "-vec_view"));
333     PetscCall(PetscObjectCompose((PetscObject) r, "__Vec_bc_zero__", NULL));
334   }
335   PetscCall(VecDestroy(&r));
336   PetscFunctionReturn(0);
337 }
338 
339 /*@C
340   DMTSCheckJacobian - Check the Jacobian of the exact solution against the residual using the Taylor Test
341 
342   Input Parameters:
343 + ts  - the TS object
344 . dm  - the DM
345 . t   - the time
346 . u   - a DM vector
347 . u_t - a DM vector
348 - tol - A tolerance for the check, or -1 to print the results instead
349 
350   Output Parameters:
351 + isLinear - Flag indicaing that the function looks linear, or NULL
352 - convRate - The rate of convergence of the linear model, or NULL
353 
354   Level: developer
355 
356 .seealso: `DNTSCheckFromOptions()`, `DMTSCheckResidual()`, `DNSNESCheckFromOptions()`, `DMSNESCheckDiscretization()`, `DMSNESCheckResidual()`
357 @*/
358 PetscErrorCode DMTSCheckJacobian(TS ts, DM dm, PetscReal t, Vec u, Vec u_t, PetscReal tol, PetscBool *isLinear, PetscReal *convRate)
359 {
360   MPI_Comm       comm;
361   PetscDS        ds;
362   Mat            J, M;
363   MatNullSpace   nullspace;
364   PetscReal      dt, shift, slope, intercept;
365   PetscBool      hasJac, hasPrec, isLin = PETSC_FALSE;
366 
367   PetscFunctionBegin;
368   PetscValidHeaderSpecific(ts, TS_CLASSID, 1);
369   PetscValidHeaderSpecific(dm, DM_CLASSID, 2);
370   PetscValidHeaderSpecific(u, VEC_CLASSID, 4);
371   if (isLinear) PetscValidBoolPointer(isLinear, 7);
372   if (convRate) PetscValidRealPointer(convRate, 8);
373   PetscCall(PetscObjectGetComm((PetscObject) ts, &comm));
374   PetscCall(DMComputeExactSolution(dm, t, u, u_t));
375   /* Create and view matrices */
376   PetscCall(TSGetTimeStep(ts, &dt));
377   shift = 1.0/dt;
378   PetscCall(DMCreateMatrix(dm, &J));
379   PetscCall(DMGetDS(dm, &ds));
380   PetscCall(PetscDSHasJacobian(ds, &hasJac));
381   PetscCall(PetscDSHasJacobianPreconditioner(ds, &hasPrec));
382   if (hasJac && hasPrec) {
383     PetscCall(DMCreateMatrix(dm, &M));
384     PetscCall(TSComputeIJacobian(ts, t, u, u_t, shift, J, M, PETSC_FALSE));
385     PetscCall(PetscObjectSetName((PetscObject) M, "Preconditioning Matrix"));
386     PetscCall(PetscObjectSetOptionsPrefix((PetscObject) M, "jacpre_"));
387     PetscCall(MatViewFromOptions(M, NULL, "-mat_view"));
388     PetscCall(MatDestroy(&M));
389   } else {
390     PetscCall(TSComputeIJacobian(ts, t, u, u_t, shift, J, J, PETSC_FALSE));
391   }
392   PetscCall(PetscObjectSetName((PetscObject) J, "Jacobian"));
393   PetscCall(PetscObjectSetOptionsPrefix((PetscObject) J, "jac_"));
394   PetscCall(MatViewFromOptions(J, NULL, "-mat_view"));
395   /* Check nullspace */
396   PetscCall(MatGetNullSpace(J, &nullspace));
397   if (nullspace) {
398     PetscBool isNull;
399     PetscCall(MatNullSpaceTest(nullspace, J, &isNull));
400     PetscCheck(isNull,comm, PETSC_ERR_PLIB, "The null space calculated for the system operator is invalid.");
401   }
402   /* Taylor test */
403   {
404     PetscRandom rand;
405     Vec         du, uhat, uhat_t, r, rhat, df;
406     PetscReal   h;
407     PetscReal  *es, *hs, *errors;
408     PetscReal   hMax = 1.0, hMin = 1e-6, hMult = 0.1;
409     PetscInt    Nv, v;
410 
411     /* Choose a perturbation direction */
412     PetscCall(PetscRandomCreate(comm, &rand));
413     PetscCall(VecDuplicate(u, &du));
414     PetscCall(VecSetRandom(du, rand));
415     PetscCall(PetscRandomDestroy(&rand));
416     PetscCall(VecDuplicate(u, &df));
417     PetscCall(MatMult(J, du, df));
418     /* Evaluate residual at u, F(u), save in vector r */
419     PetscCall(VecDuplicate(u, &r));
420     PetscCall(TSComputeIFunction(ts, t, u, u_t, r, PETSC_FALSE));
421     /* Look at the convergence of our Taylor approximation as we approach u */
422     for (h = hMax, Nv = 0; h >= hMin; h *= hMult, ++Nv);
423     PetscCall(PetscCalloc3(Nv, &es, Nv, &hs, Nv, &errors));
424     PetscCall(VecDuplicate(u, &uhat));
425     PetscCall(VecDuplicate(u, &uhat_t));
426     PetscCall(VecDuplicate(u, &rhat));
427     for (h = hMax, Nv = 0; h >= hMin; h *= hMult, ++Nv) {
428       PetscCall(VecWAXPY(uhat, h, du, u));
429       PetscCall(VecWAXPY(uhat_t, h*shift, du, u_t));
430       /* F(\hat u, \hat u_t) \approx F(u, u_t) + J(u, u_t) (uhat - u) + J_t(u, u_t) (uhat_t - u_t) = F(u) + h * J(u) du + h * shift * J_t(u) du = F(u) + h F' du */
431       PetscCall(TSComputeIFunction(ts, t, uhat, uhat_t, rhat, PETSC_FALSE));
432       PetscCall(VecAXPBYPCZ(rhat, -1.0, -h, 1.0, r, df));
433       PetscCall(VecNorm(rhat, NORM_2, &errors[Nv]));
434 
435       es[Nv] = PetscLog10Real(errors[Nv]);
436       hs[Nv] = PetscLog10Real(h);
437     }
438     PetscCall(VecDestroy(&uhat));
439     PetscCall(VecDestroy(&uhat_t));
440     PetscCall(VecDestroy(&rhat));
441     PetscCall(VecDestroy(&df));
442     PetscCall(VecDestroy(&r));
443     PetscCall(VecDestroy(&du));
444     for (v = 0; v < Nv; ++v) {
445       if ((tol >= 0) && (errors[v] > tol)) break;
446       else if (errors[v] > PETSC_SMALL)    break;
447     }
448     if (v == Nv) isLin = PETSC_TRUE;
449     PetscCall(PetscLinearRegression(Nv, hs, es, &slope, &intercept));
450     PetscCall(PetscFree3(es, hs, errors));
451     /* Slope should be about 2 */
452     if (tol >= 0) {
453       PetscCheck(isLin || PetscAbsReal(2 - slope) <= tol,comm, PETSC_ERR_ARG_WRONG, "Taylor approximation convergence rate should be 2, not %0.2f", (double) slope);
454     } else if (isLinear || convRate) {
455       if (isLinear) *isLinear = isLin;
456       if (convRate) *convRate = slope;
457     } else {
458       if (!isLin) PetscCall(PetscPrintf(comm, "Taylor approximation converging at order %3.2f\n", (double) slope));
459       else        PetscCall(PetscPrintf(comm, "Function appears to be linear\n"));
460     }
461   }
462   PetscCall(MatDestroy(&J));
463   PetscFunctionReturn(0);
464 }
465 
466 /*@C
467   DMTSCheckFromOptions - Check the residual and Jacobian functions using the exact solution by outputting some diagnostic information
468 
469   Input Parameters:
470 + ts - the TS object
471 - u  - representative TS vector
472 
473   Note: The user must call PetscDSSetExactSolution() beforehand
474 
475   Level: developer
476 @*/
477 PetscErrorCode DMTSCheckFromOptions(TS ts, Vec u)
478 {
479   DM             dm;
480   SNES           snes;
481   Vec            sol, u_t;
482   PetscReal      t;
483   PetscBool      check;
484 
485   PetscFunctionBegin;
486   PetscCall(PetscOptionsHasName(((PetscObject)ts)->options,((PetscObject)ts)->prefix, "-dmts_check", &check));
487   if (!check) PetscFunctionReturn(0);
488   PetscCall(VecDuplicate(u, &sol));
489   PetscCall(VecCopy(u, sol));
490   PetscCall(TSSetSolution(ts, u));
491   PetscCall(TSGetDM(ts, &dm));
492   PetscCall(TSSetUp(ts));
493   PetscCall(TSGetSNES(ts, &snes));
494   PetscCall(SNESSetSolution(snes, u));
495 
496   PetscCall(TSGetTime(ts, &t));
497   PetscCall(DMSNESCheckDiscretization(snes, dm, t, sol, -1.0, NULL));
498   PetscCall(DMGetGlobalVector(dm, &u_t));
499   PetscCall(DMTSCheckResidual(ts, dm, t, sol, u_t, -1.0, NULL));
500   PetscCall(DMTSCheckJacobian(ts, dm, t, sol, u_t, -1.0, NULL, NULL));
501   PetscCall(DMRestoreGlobalVector(dm, &u_t));
502 
503   PetscCall(VecDestroy(&sol));
504   PetscFunctionReturn(0);
505 }
506