Actual source code: virs.c
1: #include <../src/snes/impls/vi/rs/virsimpl.h>
2: #include <petsc/private/dmimpl.h>
3: #include <petsc/private/vecimpl.h>
5: /*@
6: SNESVIGetInactiveSet - Gets the global indices for the inactive set variables (these correspond to the degrees of freedom the linear
7: system is solved on)
9: Input Parameter:
10: . snes - the `SNES` context
12: Output Parameter:
13: . inact - inactive set index set
15: Level: advanced
17: Note:
18: See `SNESVINEWTONRSLS` for a concise description of the active and inactive sets
20: .seealso: [](ch_snes), `SNES`, `SNESVINEWTONRSLS`
21: @*/
22: PetscErrorCode SNESVIGetInactiveSet(SNES snes, IS *inact)
23: {
24: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
26: PetscFunctionBegin;
27: *inact = vi->IS_inact;
28: PetscFunctionReturn(PETSC_SUCCESS);
29: }
31: /*
32: Provides a wrapper to a DM to allow it to be used to generated the interpolation/restriction from the DM for the smaller matrices and vectors
33: defined by the reduced space method.
35: Simple calls the regular DM interpolation and restricts it to operation on the variables not associated with active constraints.
36: */
37: typedef struct {
38: PetscInt n; /* size of vectors in the reduced DM space */
39: IS inactive;
41: PetscErrorCode (*createinterpolation)(DM, DM, Mat *, Vec *); /* DM's original routines */
42: PetscErrorCode (*coarsen)(DM, MPI_Comm, DM *);
43: PetscErrorCode (*createglobalvector)(DM, Vec *);
44: PetscErrorCode (*createinjection)(DM, DM, Mat *);
45: PetscErrorCode (*hascreateinjection)(DM, PetscBool *);
47: DM dm; /* when destroying this object we need to reset the above function into the base DM */
48: } DM_SNESVI;
50: /*
51: DMCreateGlobalVector_SNESVI - Creates global vector of the size of the reduced space
52: */
53: static PetscErrorCode DMCreateGlobalVector_SNESVI(DM dm, Vec *vec)
54: {
55: PetscContainer isnes;
56: DM_SNESVI *dmsnesvi;
58: PetscFunctionBegin;
59: PetscCall(PetscObjectQuery((PetscObject)dm, "VI", (PetscObject *)&isnes));
60: PetscCheck(isnes, PetscObjectComm((PetscObject)dm), PETSC_ERR_PLIB, "Composed SNES is missing");
61: PetscCall(PetscContainerGetPointer(isnes, &dmsnesvi));
62: PetscCall(VecCreateMPI(PetscObjectComm((PetscObject)dm), dmsnesvi->n, PETSC_DETERMINE, vec));
63: PetscCall(VecSetDM(*vec, dm));
64: PetscFunctionReturn(PETSC_SUCCESS);
65: }
67: /*
68: DMCreateInterpolation_SNESVI - Modifieds the interpolation obtained from the DM by removing all rows and columns associated with active constraints.
69: */
70: static PetscErrorCode DMCreateInterpolation_SNESVI(DM dm1, DM dm2, Mat *mat, Vec *vec)
71: {
72: PetscContainer isnes;
73: DM_SNESVI *dmsnesvi1, *dmsnesvi2;
74: Mat interp;
76: PetscFunctionBegin;
77: PetscCall(PetscObjectQuery((PetscObject)dm1, "VI", (PetscObject *)&isnes));
78: PetscCheck(isnes, PetscObjectComm((PetscObject)dm1), PETSC_ERR_PLIB, "Composed VI data structure is missing");
79: PetscCall(PetscContainerGetPointer(isnes, &dmsnesvi1));
80: PetscCall(PetscObjectQuery((PetscObject)dm2, "VI", (PetscObject *)&isnes));
81: PetscCheck(isnes, PetscObjectComm((PetscObject)dm2), PETSC_ERR_PLIB, "Composed VI data structure is missing");
82: PetscCall(PetscContainerGetPointer(isnes, &dmsnesvi2));
84: PetscCall((*dmsnesvi1->createinterpolation)(dm1, dm2, &interp, NULL));
85: PetscCall(MatCreateSubMatrix(interp, dmsnesvi2->inactive, dmsnesvi1->inactive, MAT_INITIAL_MATRIX, mat));
86: PetscCall(MatDestroy(&interp));
87: *vec = NULL;
88: PetscFunctionReturn(PETSC_SUCCESS);
89: }
91: /*
92: DMCoarsen_SNESVI - Computes the regular coarsened DM then computes additional information about its inactive set
93: */
94: static PetscErrorCode DMCoarsen_SNESVI(DM dm1, MPI_Comm comm, DM *dm2)
95: {
96: PetscContainer isnes;
97: DM_SNESVI *dmsnesvi1;
98: Vec finemarked, coarsemarked;
99: IS inactive;
100: Mat inject;
101: const PetscInt *index;
102: PetscInt n, k, cnt = 0, rstart, *coarseindex;
103: PetscScalar *marked;
105: PetscFunctionBegin;
106: PetscCall(PetscObjectQuery((PetscObject)dm1, "VI", (PetscObject *)&isnes));
107: PetscCheck(isnes, PetscObjectComm((PetscObject)dm1), PETSC_ERR_PLIB, "Composed VI data structure is missing");
108: PetscCall(PetscContainerGetPointer(isnes, &dmsnesvi1));
110: /* get the original coarsen */
111: PetscCall((*dmsnesvi1->coarsen)(dm1, comm, dm2));
113: /* not sure why this extra reference is needed, but without the dm2 disappears too early */
114: /* Updating the KSPCreateVecs() to avoid using DMGetGlobalVector() when matrix is available removes the need for this reference? */
115: /* PetscCall(PetscObjectReference((PetscObject)*dm2));*/
117: /* need to set back global vectors in order to use the original injection */
118: PetscCall(DMClearGlobalVectors(dm1));
120: dm1->ops->createglobalvector = dmsnesvi1->createglobalvector;
122: PetscCall(DMCreateGlobalVector(dm1, &finemarked));
123: PetscCall(DMCreateGlobalVector(*dm2, &coarsemarked));
125: /*
126: fill finemarked with locations of inactive points
127: */
128: PetscCall(ISGetIndices(dmsnesvi1->inactive, &index));
129: PetscCall(ISGetLocalSize(dmsnesvi1->inactive, &n));
130: for (k = 0; k < n; k++) PetscCall(VecSetValue(finemarked, index[k], 1.0, INSERT_VALUES));
131: PetscCall(VecAssemblyBegin(finemarked));
132: PetscCall(VecAssemblyEnd(finemarked));
134: PetscCall(DMCreateInjection(*dm2, dm1, &inject));
135: PetscCall(MatRestrict(inject, finemarked, coarsemarked));
136: PetscCall(MatDestroy(&inject));
138: /*
139: create index set list of coarse inactive points from coarsemarked
140: */
141: PetscCall(VecGetLocalSize(coarsemarked, &n));
142: PetscCall(VecGetOwnershipRange(coarsemarked, &rstart, NULL));
143: PetscCall(VecGetArray(coarsemarked, &marked));
144: for (k = 0; k < n; k++) {
145: if (marked[k] != 0.0) cnt++;
146: }
147: PetscCall(PetscMalloc1(cnt, &coarseindex));
148: cnt = 0;
149: for (k = 0; k < n; k++) {
150: if (marked[k] != 0.0) coarseindex[cnt++] = k + rstart;
151: }
152: PetscCall(VecRestoreArray(coarsemarked, &marked));
153: PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)coarsemarked), cnt, coarseindex, PETSC_OWN_POINTER, &inactive));
155: PetscCall(DMClearGlobalVectors(dm1));
157: dm1->ops->createglobalvector = DMCreateGlobalVector_SNESVI;
159: PetscCall(DMSetVI(*dm2, inactive));
161: PetscCall(VecDestroy(&finemarked));
162: PetscCall(VecDestroy(&coarsemarked));
163: PetscCall(ISDestroy(&inactive));
164: PetscFunctionReturn(PETSC_SUCCESS);
165: }
167: static PetscErrorCode DMDestroy_SNESVI(PetscCtxRt ctx)
168: {
169: DM_SNESVI *dmsnesvi = *(DM_SNESVI **)ctx;
171: PetscFunctionBegin;
172: /* reset the base methods in the DM object that were changed when the DM_SNESVI was reset */
173: dmsnesvi->dm->ops->createinterpolation = dmsnesvi->createinterpolation;
174: dmsnesvi->dm->ops->coarsen = dmsnesvi->coarsen;
175: dmsnesvi->dm->ops->createglobalvector = dmsnesvi->createglobalvector;
176: dmsnesvi->dm->ops->createinjection = dmsnesvi->createinjection;
177: dmsnesvi->dm->ops->hascreateinjection = dmsnesvi->hascreateinjection;
178: /* need to clear out this vectors because some of them may not have a reference to the DM
179: but they are counted as having references to the DM in DMDestroy() */
180: PetscCall(DMClearGlobalVectors(dmsnesvi->dm));
182: PetscCall(ISDestroy(&dmsnesvi->inactive));
183: PetscCall(PetscFree(dmsnesvi));
184: PetscFunctionReturn(PETSC_SUCCESS);
185: }
187: /*@
188: DMSetVI - Marks a `DM` as associated with a VI problem. This causes the interpolation/restriction operators to
189: be restricted to only those variables NOT associated with active constraints.
191: Logically Collective
193: Input Parameters:
194: + dm - the `DM` object
195: - inactive - an `IS` indicating which points are currently not active
197: Level: intermediate
199: .seealso: [](ch_snes), `SNES`, `SNESVINEWTONRSLS`, `SNESVIGetInactiveSet()`
200: @*/
201: PetscErrorCode DMSetVI(DM dm, IS inactive)
202: {
203: PetscContainer isnes;
204: DM_SNESVI *dmsnesvi;
206: PetscFunctionBegin;
207: if (!dm) PetscFunctionReturn(PETSC_SUCCESS);
209: PetscCall(PetscObjectReference((PetscObject)inactive));
211: PetscCall(PetscObjectQuery((PetscObject)dm, "VI", (PetscObject *)&isnes));
212: if (!isnes) {
213: PetscCall(PetscNew(&dmsnesvi));
214: PetscCall(PetscObjectContainerCompose((PetscObject)dm, "VI", dmsnesvi, DMDestroy_SNESVI));
216: dmsnesvi->createinterpolation = dm->ops->createinterpolation;
217: dm->ops->createinterpolation = DMCreateInterpolation_SNESVI;
218: dmsnesvi->coarsen = dm->ops->coarsen;
219: dm->ops->coarsen = DMCoarsen_SNESVI;
220: dmsnesvi->createglobalvector = dm->ops->createglobalvector;
221: dm->ops->createglobalvector = DMCreateGlobalVector_SNESVI;
222: dmsnesvi->createinjection = dm->ops->createinjection;
223: dm->ops->createinjection = NULL;
224: dmsnesvi->hascreateinjection = dm->ops->hascreateinjection;
225: dm->ops->hascreateinjection = NULL;
226: } else {
227: PetscCall(PetscContainerGetPointer(isnes, &dmsnesvi));
228: PetscCall(ISDestroy(&dmsnesvi->inactive));
229: }
230: PetscCall(DMClearGlobalVectors(dm));
231: PetscCall(ISGetLocalSize(inactive, &dmsnesvi->n));
233: dmsnesvi->inactive = inactive;
234: dmsnesvi->dm = dm;
235: PetscFunctionReturn(PETSC_SUCCESS);
236: }
238: /*
239: DMDestroyVI - Frees the DM_SNESVI object contained in the DM
240: - also resets the function pointers in the DM for createinterpolation() etc to use the original DM
241: */
242: PetscErrorCode DMDestroyVI(DM dm)
243: {
244: PetscFunctionBegin;
245: if (!dm) PetscFunctionReturn(PETSC_SUCCESS);
246: PetscCall(PetscObjectCompose((PetscObject)dm, "VI", (PetscObject)NULL));
247: PetscFunctionReturn(PETSC_SUCCESS);
248: }
250: /* Create active and inactive set vectors. The local size of this vector is set and PETSc computes the global size */
251: static PetscErrorCode SNESCreateSubVectors_VINEWTONRSLS(SNES snes, PetscInt n, Vec *newv)
252: {
253: Vec v;
255: PetscFunctionBegin;
256: PetscCall(VecCreate(PetscObjectComm((PetscObject)snes), &v));
257: PetscCall(VecSetSizes(v, n, PETSC_DECIDE));
258: PetscCall(VecSetType(v, VECSTANDARD));
259: *newv = v;
260: PetscFunctionReturn(PETSC_SUCCESS);
261: }
263: /* Resets the snes PC and KSP when the active set sizes change */
264: static PetscErrorCode SNESVIResetPCandKSP(SNES snes, Mat Amat, Mat Pmat)
265: {
266: KSP snesksp;
268: PetscFunctionBegin;
269: PetscCall(SNESGetKSP(snes, &snesksp));
270: PetscCall(KSPReset(snesksp));
271: PetscCall(KSPResetFromOptions(snesksp));
273: /*
274: KSP kspnew;
275: PC pcnew;
276: MatSolverType stype;
278: PetscCall(KSPCreate(PetscObjectComm((PetscObject)snes),&kspnew));
279: kspnew->pc_side = snesksp->pc_side;
280: kspnew->rtol = snesksp->rtol;
281: kspnew->abstol = snesksp->abstol;
282: kspnew->max_it = snesksp->max_it;
283: PetscCall(KSPSetType(kspnew,((PetscObject)snesksp)->type_name));
284: PetscCall(KSPGetPC(kspnew,&pcnew));
285: PetscCall(PCSetType(kspnew->pc,((PetscObject)snesksp->pc)->type_name));
286: PetscCall(PCSetOperators(kspnew->pc,Amat,Pmat));
287: PetscCall(PCFactorGetMatSolverType(snesksp->pc,&stype));
288: PetscCall(PCFactorSetMatSolverType(kspnew->pc,stype));
289: PetscCall(KSPDestroy(&snesksp));
290: snes->ksp = kspnew;
291: PetscCall(KSPSetFromOptions(kspnew));*/
292: PetscFunctionReturn(PETSC_SUCCESS);
293: }
295: /* Variational Inequality solver using reduce space method. No semismooth algorithm is
296: implemented in this algorithm. It basically identifies the active constraints and does
297: a linear solve on the other variables (those not associated with the active constraints). */
298: static PetscErrorCode SNESSolve_VINEWTONRSLS(SNES snes)
299: {
300: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
301: PetscInt maxits, i, lits;
302: SNESLineSearchReason lsreason;
303: PetscReal fnorm, gnorm, xnorm = 0, ynorm;
304: Vec Y, X, F;
305: KSPConvergedReason kspreason;
306: KSP ksp;
307: PC pc;
309: PetscFunctionBegin;
310: /* Multigrid must use Galerkin for coarse grids with active set/reduced space methods; cannot rediscretize on coarser grids*/
311: PetscCall(SNESGetKSP(snes, &ksp));
312: PetscCall(KSPGetPC(ksp, &pc));
313: PetscCall(PCMGSetGalerkin(pc, PC_MG_GALERKIN_BOTH));
315: snes->numFailures = 0;
316: snes->numLinearSolveFailures = 0;
317: snes->reason = SNES_CONVERGED_ITERATING;
319: maxits = snes->max_its; /* maximum number of iterations */
320: X = snes->vec_sol; /* solution vector */
321: F = snes->vec_func; /* residual vector */
322: Y = snes->work[0]; /* work vectors */
324: PetscCall(SNESLineSearchSetVIFunctions(snes->linesearch, SNESVIProjectOntoBounds, SNESVIComputeInactiveSetFnorm, SNESVIComputeInactiveSetFtY));
325: PetscCall(SNESLineSearchSetVecs(snes->linesearch, X, NULL, NULL, NULL, NULL));
326: PetscCall(SNESLineSearchSetUp(snes->linesearch));
328: PetscCall(PetscObjectSAWsTakeAccess((PetscObject)snes));
329: snes->iter = 0;
330: snes->norm = 0.0;
331: PetscCall(PetscObjectSAWsGrantAccess((PetscObject)snes));
333: PetscCall(SNESVIProjectOntoBounds(snes, X));
334: PetscCall(SNESComputeFunction(snes, X, F));
335: PetscCall(SNESVIComputeInactiveSetFnorm(snes, F, X, &fnorm));
336: PetscCall(VecNorm(X, NORM_2, &xnorm)); /* xnorm <- ||x|| */
337: SNESCheckFunctionDomainError(snes, fnorm);
338: PetscCall(PetscObjectSAWsTakeAccess((PetscObject)snes));
339: snes->norm = fnorm;
340: PetscCall(PetscObjectSAWsGrantAccess((PetscObject)snes));
341: PetscCall(SNESLogConvergenceHistory(snes, fnorm, 0));
343: /* test convergence */
344: PetscCall(SNESConverged(snes, 0, 0.0, 0.0, fnorm));
345: PetscCall(SNESMonitor(snes, 0, fnorm));
346: if (snes->reason) PetscFunctionReturn(PETSC_SUCCESS);
348: for (i = 0; i < maxits; i++) {
349: IS IS_act; /* _act -> active set _inact -> inactive set */
350: IS IS_redact; /* redundant active set */
351: VecScatter scat_act, scat_inact;
352: PetscInt nis_act, nis_inact;
353: Vec Y_act, Y_inact, F_inact;
354: Mat jac_inact_inact, prejac_inact_inact;
355: PetscBool isequal;
357: /* Call general purpose update function */
358: PetscTryTypeMethod(snes, update, snes->iter);
359: PetscCall(SNESComputeJacobian(snes, X, snes->jacobian, snes->jacobian_pre));
360: SNESCheckJacobianDomainError(snes);
362: /* Create active and inactive index sets */
364: /*original
365: PetscCall(SNESVICreateIndexSets_RS(snes,X,F,&IS_act,&vi->IS_inact));
366: */
367: PetscCall(SNESVIGetActiveSetIS(snes, X, F, &IS_act));
369: if (vi->checkredundancy) {
370: PetscCall((*vi->checkredundancy)(snes, IS_act, &IS_redact, vi->ctxP));
371: if (IS_redact) {
372: PetscCall(ISSort(IS_redact));
373: PetscCall(ISComplement(IS_redact, X->map->rstart, X->map->rend, &vi->IS_inact));
374: PetscCall(ISDestroy(&IS_redact));
375: } else {
376: PetscCall(ISComplement(IS_act, X->map->rstart, X->map->rend, &vi->IS_inact));
377: }
378: } else {
379: PetscCall(ISComplement(IS_act, X->map->rstart, X->map->rend, &vi->IS_inact));
380: }
382: /* Create inactive set submatrix */
383: PetscCall(MatCreateSubMatrix(snes->jacobian, vi->IS_inact, vi->IS_inact, MAT_INITIAL_MATRIX, &jac_inact_inact));
385: if (0) { /* Dead code (temporary developer hack) */
386: IS keptrows;
387: PetscCall(MatFindNonzeroRows(jac_inact_inact, &keptrows));
388: if (keptrows) {
389: PetscInt cnt, *nrows, k;
390: const PetscInt *krows, *inact;
391: PetscInt rstart;
393: PetscCall(MatGetOwnershipRange(jac_inact_inact, &rstart, NULL));
394: PetscCall(MatDestroy(&jac_inact_inact));
395: PetscCall(ISDestroy(&IS_act));
397: PetscCall(ISGetLocalSize(keptrows, &cnt));
398: PetscCall(ISGetIndices(keptrows, &krows));
399: PetscCall(ISGetIndices(vi->IS_inact, &inact));
400: PetscCall(PetscMalloc1(cnt, &nrows));
401: for (k = 0; k < cnt; k++) nrows[k] = inact[krows[k] - rstart];
402: PetscCall(ISRestoreIndices(keptrows, &krows));
403: PetscCall(ISRestoreIndices(vi->IS_inact, &inact));
404: PetscCall(ISDestroy(&keptrows));
405: PetscCall(ISDestroy(&vi->IS_inact));
407: PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)snes), cnt, nrows, PETSC_OWN_POINTER, &vi->IS_inact));
408: PetscCall(ISComplement(vi->IS_inact, F->map->rstart, F->map->rend, &IS_act));
409: PetscCall(MatCreateSubMatrix(snes->jacobian, vi->IS_inact, vi->IS_inact, MAT_INITIAL_MATRIX, &jac_inact_inact));
410: }
411: }
412: PetscCall(DMSetVI(snes->dm, vi->IS_inact));
413: /* remove later */
415: /*
416: PetscCall(VecView(vi->xu,PETSC_VIEWER_BINARY_(((PetscObject)vi->xu)->comm)));
417: PetscCall(VecView(vi->xl,PETSC_VIEWER_BINARY_(((PetscObject)vi->xl)->comm)));
418: PetscCall(VecView(X,PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)X))));
419: PetscCall(VecView(F,PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)F))));
420: PetscCall(ISView(vi->IS_inact,PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)vi->IS_inact))));
421: */
423: /* Get sizes of active and inactive sets */
424: PetscCall(ISGetLocalSize(IS_act, &nis_act));
425: PetscCall(ISGetLocalSize(vi->IS_inact, &nis_inact));
427: /* Create active and inactive set vectors */
428: PetscCall(SNESCreateSubVectors_VINEWTONRSLS(snes, nis_inact, &F_inact));
429: PetscCall(SNESCreateSubVectors_VINEWTONRSLS(snes, nis_act, &Y_act));
430: PetscCall(SNESCreateSubVectors_VINEWTONRSLS(snes, nis_inact, &Y_inact));
432: /* Create scatter contexts */
433: PetscCall(VecScatterCreate(Y, IS_act, Y_act, NULL, &scat_act));
434: PetscCall(VecScatterCreate(Y, vi->IS_inact, Y_inact, NULL, &scat_inact));
436: /* Do a vec scatter to active and inactive set vectors */
437: PetscCall(VecScatterBegin(scat_inact, F, F_inact, INSERT_VALUES, SCATTER_FORWARD));
438: PetscCall(VecScatterEnd(scat_inact, F, F_inact, INSERT_VALUES, SCATTER_FORWARD));
440: PetscCall(VecScatterBegin(scat_act, Y, Y_act, INSERT_VALUES, SCATTER_FORWARD));
441: PetscCall(VecScatterEnd(scat_act, Y, Y_act, INSERT_VALUES, SCATTER_FORWARD));
443: PetscCall(VecScatterBegin(scat_inact, Y, Y_inact, INSERT_VALUES, SCATTER_FORWARD));
444: PetscCall(VecScatterEnd(scat_inact, Y, Y_inact, INSERT_VALUES, SCATTER_FORWARD));
446: /* Active set direction = 0 */
447: PetscCall(VecSet(Y_act, 0));
448: if (snes->jacobian != snes->jacobian_pre) PetscCall(MatCreateSubMatrix(snes->jacobian_pre, vi->IS_inact, vi->IS_inact, MAT_INITIAL_MATRIX, &prejac_inact_inact));
449: else prejac_inact_inact = jac_inact_inact;
451: PetscCall(ISEqual(vi->IS_inact_prev, vi->IS_inact, &isequal));
452: if (!isequal) {
453: PetscCall(SNESVIResetPCandKSP(snes, jac_inact_inact, prejac_inact_inact));
454: PetscCall(PCFieldSplitRestrictIS(pc, vi->IS_inact));
455: }
457: /* PetscCall(ISView(vi->IS_inact,0)); */
458: /* PetscCall(ISView(IS_act,0));*/
459: /* ierr = MatView(snes->jacobian_pre,0); */
461: PetscCall(KSPSetOperators(snes->ksp, jac_inact_inact, prejac_inact_inact));
462: PetscCall(KSPSetUp(snes->ksp));
463: {
464: PC pc;
465: PetscBool flg;
466: PetscCall(KSPGetPC(snes->ksp, &pc));
467: PetscCall(PetscObjectTypeCompare((PetscObject)pc, PCFIELDSPLIT, &flg));
468: if (flg) {
469: KSP *subksps;
470: PetscCall(PCFieldSplitGetSubKSP(pc, NULL, &subksps));
471: PetscCall(KSPGetPC(subksps[0], &pc));
472: PetscCall(PetscFree(subksps));
473: PetscCall(PetscObjectTypeCompare((PetscObject)pc, PCBJACOBI, &flg));
474: if (flg) {
475: PetscInt n, N = 101 * 101, j, cnts[3] = {0, 0, 0};
476: const PetscInt *ii;
478: PetscCall(ISGetSize(vi->IS_inact, &n));
479: PetscCall(ISGetIndices(vi->IS_inact, &ii));
480: for (j = 0; j < n; j++) {
481: if (ii[j] < N) cnts[0]++;
482: else if (ii[j] < 2 * N) cnts[1]++;
483: else if (ii[j] < 3 * N) cnts[2]++;
484: }
485: PetscCall(ISRestoreIndices(vi->IS_inact, &ii));
487: PetscCall(PCBJacobiSetTotalBlocks(pc, 3, cnts));
488: }
489: }
490: }
492: PetscCall(KSPSolve(snes->ksp, F_inact, Y_inact));
493: PetscCall(VecScatterBegin(scat_act, Y_act, Y, INSERT_VALUES, SCATTER_REVERSE));
494: PetscCall(VecScatterEnd(scat_act, Y_act, Y, INSERT_VALUES, SCATTER_REVERSE));
495: PetscCall(VecScatterBegin(scat_inact, Y_inact, Y, INSERT_VALUES, SCATTER_REVERSE));
496: PetscCall(VecScatterEnd(scat_inact, Y_inact, Y, INSERT_VALUES, SCATTER_REVERSE));
498: PetscCall(VecDestroy(&F_inact));
499: PetscCall(VecDestroy(&Y_act));
500: PetscCall(VecDestroy(&Y_inact));
501: PetscCall(VecScatterDestroy(&scat_act));
502: PetscCall(VecScatterDestroy(&scat_inact));
503: PetscCall(ISDestroy(&IS_act));
504: if (!isequal) {
505: PetscCall(ISDestroy(&vi->IS_inact_prev));
506: PetscCall(ISDuplicate(vi->IS_inact, &vi->IS_inact_prev));
507: }
508: PetscCall(ISDestroy(&vi->IS_inact));
509: PetscCall(MatDestroy(&jac_inact_inact));
510: if (snes->jacobian != snes->jacobian_pre) PetscCall(MatDestroy(&prejac_inact_inact));
512: PetscCall(KSPGetConvergedReason(snes->ksp, &kspreason));
513: if (kspreason < 0) {
514: if (++snes->numLinearSolveFailures >= snes->maxLinearSolveFailures) {
515: PetscCall(PetscInfo(snes, "iter=%" PetscInt_FMT ", number linear solve failures %" PetscInt_FMT " greater than current SNES allowed, stopping solve\n", snes->iter, snes->numLinearSolveFailures));
516: snes->reason = SNES_DIVERGED_LINEAR_SOLVE;
517: break;
518: }
519: }
521: PetscCall(KSPGetIterationNumber(snes->ksp, &lits));
522: snes->linear_its += lits;
523: PetscCall(PetscInfo(snes, "iter=%" PetscInt_FMT ", linear solve iterations=%" PetscInt_FMT "\n", snes->iter, lits));
524: /*
525: if (snes->ops->precheck) {
526: PetscBool changed_y = PETSC_FALSE;
527: PetscUseTypeMethod(snes,precheck ,X,Y,snes->precheck,&changed_y);
528: }
530: if (PetscLogPrintInfo) PetscCall(SNESVICheckResidual_Private(snes,snes->jacobian,F,Y,G,W));
531: */
532: /* Compute a (scaled) negative update in the line search routine:
533: Y <- X - lambda*Y
534: and evaluate G = function(Y) (depends on the line search).
535: */
536: PetscCall(VecCopy(Y, snes->vec_sol_update));
537: ynorm = 1;
538: gnorm = fnorm;
539: PetscCall(SNESLineSearchApply(snes->linesearch, X, F, &gnorm, Y));
540: PetscCall(DMDestroyVI(snes->dm));
541: if (snes->reason) break;
542: PetscCall(SNESLineSearchGetReason(snes->linesearch, &lsreason));
543: if (lsreason) {
544: if (snes->stol * xnorm > ynorm) {
545: snes->reason = SNES_CONVERGED_SNORM_RELATIVE;
546: break;
547: } else if (lsreason == SNES_LINESEARCH_FAILED_FUNCTION_DOMAIN) {
548: snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
549: break;
550: } else if (lsreason == SNES_LINESEARCH_FAILED_NANORINF) {
551: snes->reason = SNES_DIVERGED_FUNCTION_NANORINF;
552: break;
553: } else if (lsreason == SNES_LINESEARCH_FAILED_OBJECTIVE_DOMAIN) {
554: snes->reason = SNES_DIVERGED_OBJECTIVE_DOMAIN;
555: break;
556: } else if (lsreason == SNES_LINESEARCH_FAILED_JACOBIAN_DOMAIN) {
557: snes->reason = SNES_DIVERGED_JACOBIAN_DOMAIN;
558: break;
559: } else if (++snes->numFailures >= snes->maxFailures) {
560: PetscBool ismin;
562: snes->reason = SNES_DIVERGED_LINE_SEARCH;
563: PetscCall(SNESVICheckLocalMin_Private(snes, snes->jacobian, F, X, gnorm, &ismin));
564: if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN;
565: break;
566: }
567: }
568: PetscCall(SNESLineSearchGetNorms(snes->linesearch, &xnorm, &gnorm, &ynorm));
569: PetscCall(PetscInfo(snes, "fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n", (double)fnorm, (double)gnorm, (double)ynorm, (int)lsreason));
570: /* Update function and solution vectors */
571: fnorm = gnorm;
572: /* Monitor convergence */
573: PetscCall(PetscObjectSAWsTakeAccess((PetscObject)snes));
574: snes->iter = i + 1;
575: snes->norm = fnorm;
576: snes->xnorm = xnorm;
577: snes->ynorm = ynorm;
578: PetscCall(PetscObjectSAWsGrantAccess((PetscObject)snes));
579: PetscCall(SNESLogConvergenceHistory(snes, snes->norm, lits));
580: /* Test for convergence, xnorm = || X || */
581: if (snes->ops->converged != SNESConvergedSkip) PetscCall(VecNorm(X, NORM_2, &xnorm));
582: PetscCall(SNESConverged(snes, snes->iter, xnorm, ynorm, fnorm));
583: PetscCall(SNESMonitor(snes, snes->iter, snes->norm));
584: if (snes->reason) break;
585: }
586: /* make sure that the VI information attached to the DM is removed if the for loop above was broken early due to some exceptional conditional */
587: PetscCall(DMDestroyVI(snes->dm));
588: PetscFunctionReturn(PETSC_SUCCESS);
589: }
591: /*@C
592: SNESVISetRedundancyCheck - Provide a function to check for any redundancy in the VI active set
594: Logically Collective
596: Input Parameters:
597: + snes - the `SNESVINEWTONRSLS` context
598: . func - the function to check of redundancies
599: - ctx - optional context used by the function
601: Calling sequence of func:
602: + snes - the `SNES` context
603: . is_act - the set of points in the active sets
604: . is_redact - output, the set of points in the non-redundant active set
605: - ctx - optional context
607: Level: advanced
609: Note:
610: Sometimes the inactive set will result in a singular sub-Jacobian problem that needs to be solved, this allows the user,
611: when they know more about their specific problem to provide a function that removes the redundancy that results in the singular linear system
613: See `SNESVINEWTONRSLS` for a concise description of the active and inactive sets
615: .seealso: [](ch_snes), `SNES`, `SNESVINEWTONRSLS`, `SNESVIGetInactiveSet()`, `DMSetVI()`
616: @*/
617: PetscErrorCode SNESVISetRedundancyCheck(SNES snes, PetscErrorCode (*func)(SNES snes, IS is_act, IS *is_redact, PetscCtx ctx), PetscCtx ctx)
618: {
619: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
621: PetscFunctionBegin;
623: vi->checkredundancy = func;
624: vi->ctxP = ctx;
625: PetscFunctionReturn(PETSC_SUCCESS);
626: }
628: #if defined(PETSC_HAVE_MATLAB)
629: #include <engine.h>
630: #include <mex.h>
631: typedef struct {
632: char *funcname;
633: mxArray *ctx;
634: } SNESMatlabContext;
636: PetscErrorCode SNESVIRedundancyCheck_Matlab(SNES snes, IS is_act, IS *is_redact, PetscCtx ctx)
637: {
638: SNESMatlabContext *sctx = (SNESMatlabContext *)ctx;
639: int nlhs = 1, nrhs = 5;
640: mxArray *plhs[1], *prhs[5];
641: long long int l1 = 0, l2 = 0, ls = 0;
642: PetscInt *indices = NULL;
644: PetscFunctionBegin;
647: PetscAssertPointer(is_redact, 3);
648: PetscCheckSameComm(snes, 1, is_act, 2);
650: /* Create IS for reduced active set of size 0, its size and indices will
651: bet set by the MATLAB function */
652: PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)snes), 0, indices, PETSC_OWN_POINTER, is_redact));
653: /* call MATLAB function in ctx */
654: PetscCall(PetscArraycpy(&ls, &snes, 1));
655: PetscCall(PetscArraycpy(&l1, &is_act, 1));
656: PetscCall(PetscArraycpy(&l2, is_redact, 1));
657: prhs[0] = mxCreateDoubleScalar((double)ls);
658: prhs[1] = mxCreateDoubleScalar((double)l1);
659: prhs[2] = mxCreateDoubleScalar((double)l2);
660: prhs[3] = mxCreateString(sctx->funcname);
661: prhs[4] = sctx->ctx;
662: PetscCall(mexCallMATLAB(nlhs, plhs, nrhs, prhs, "PetscSNESVIRedundancyCheckInternal"));
663: PetscCall(mxGetScalar(plhs[0]));
664: mxDestroyArray(prhs[0]);
665: mxDestroyArray(prhs[1]);
666: mxDestroyArray(prhs[2]);
667: mxDestroyArray(prhs[3]);
668: mxDestroyArray(plhs[0]);
669: PetscFunctionReturn(PETSC_SUCCESS);
670: }
672: PetscErrorCode SNESVISetRedundancyCheckMatlab(SNES snes, const char *func, mxArray *ctx)
673: {
674: SNESMatlabContext *sctx;
676: PetscFunctionBegin;
677: /* currently sctx is memory bleed */
678: PetscCall(PetscNew(&sctx));
679: PetscCall(PetscStrallocpy(func, &sctx->funcname));
680: sctx->ctx = mxDuplicateArray(ctx);
681: PetscCall(SNESVISetRedundancyCheck(snes, SNESVIRedundancyCheck_Matlab, sctx));
682: PetscFunctionReturn(PETSC_SUCCESS);
683: }
685: #endif
687: static PetscErrorCode SNESSetUp_VINEWTONRSLS(SNES snes)
688: {
689: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
690: PetscInt *indices;
691: PetscInt i, n, rstart, rend;
692: SNESLineSearch linesearch;
694: PetscFunctionBegin;
695: PetscCall(SNESSetUp_VI(snes));
697: /* Set up previous active index set for the first snes solve
698: vi->IS_inact_prev = 0,1,2,....N */
700: PetscCall(VecGetOwnershipRange(snes->work[0], &rstart, &rend));
701: PetscCall(VecGetLocalSize(snes->work[0], &n));
702: PetscCall(PetscMalloc1(n, &indices));
703: for (i = 0; i < n; i++) indices[i] = rstart + i;
704: PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)snes), n, indices, PETSC_OWN_POINTER, &vi->IS_inact_prev));
706: /* set the line search functions */
707: if (!snes->linesearch) {
708: PetscCall(SNESGetLineSearch(snes, &linesearch));
709: PetscCall(SNESLineSearchSetType(linesearch, SNESLINESEARCHBT));
710: }
711: PetscFunctionReturn(PETSC_SUCCESS);
712: }
714: static PetscErrorCode SNESReset_VINEWTONRSLS(SNES snes)
715: {
716: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
718: PetscFunctionBegin;
719: PetscCall(SNESReset_VI(snes));
720: PetscCall(ISDestroy(&vi->IS_inact_prev));
721: PetscFunctionReturn(PETSC_SUCCESS);
722: }
724: /*MC
725: SNESVINEWTONRSLS - Reduced space active set solvers for variational inequalities based on Newton's method
727: Options Database Keys:
728: + -snes_type (vinewtonssls|vinewtonrsls) - A semi-smooth solver or a reduced space active set method
729: . -snes_vi_zero_tolerance - Tolerance for considering $u_i$ value to be on a bound.
730: . -snes_vi_monitor - Prints the number of active constraints (inactive set points) at each iteration.
731: . -snes_vi_monitor_residual - View the residual vector at each iteration, using zero for active constraints (i.e. the inactive variables).
732: - -snes_vi_monitor_active - View the active set by outputting a one for vector components in the active set and zero for the inactive.
734: Level: beginner
736: Note:
737: Reduced-space (active set methods) work as follows at each iteration\:
738: - The algorithm produces an inactive set of variables, that is a list of variables whose values will not be changed in the current iteration, i.e. they
739: are to be constrained to their current values. These are all the variables that are on the lower bound, that is $u_i = L_i$ with also $[F(u)]_i \ge 0$ or
740: the upper bound $u_i = U_i$ with also $[F(u)]_i \le 0.$
741: - A step direction is obtained by solving the linear system arising from the Jacobian used in Newton's method but with the inactive variables removed
742: from both the rows and columns.
743: - A line search is then used to update the active variables (the inactive set of variables are not changed).
745: The inactive set is chosen based on the sign of $[F(u)]_i$ because this gives exactly the set of points that would be moved outside of the domain given
746: an infinitesimal Newton (or even Richardson) step and our goal is to remain within the bounds, that is, to continue to satisfy the inequality constraints.
748: See {cite}`benson2006flexible`
750: .seealso: [](ch_snes), `SNESVISetVariableBounds()`, `SNESVISetComputeVariableBounds()`, `SNESCreate()`, `SNES`, `SNESSetType()`, `SNESVINEWTONSSLS`, `SNESNEWTONTR`, `SNESLineSearchSetType()`, `SNESLineSearchSetPostCheck()`, `SNESLineSearchSetPreCheck()`, `SNESVIGetInactiveSet()`, `DMSetVI()`, `SNESVISetRedundancyCheck()`
751: M*/
752: PETSC_EXTERN PetscErrorCode SNESCreate_VINEWTONRSLS(SNES snes)
753: {
754: SNES_VINEWTONRSLS *vi;
755: SNESLineSearch linesearch;
757: PetscFunctionBegin;
758: snes->ops->reset = SNESReset_VINEWTONRSLS;
759: snes->ops->setup = SNESSetUp_VINEWTONRSLS;
760: snes->ops->solve = SNESSolve_VINEWTONRSLS;
761: snes->ops->destroy = SNESDestroy_VI;
762: snes->ops->setfromoptions = SNESSetFromOptions_VI;
763: snes->ops->view = NULL;
764: snes->ops->converged = SNESConvergedDefault_VI;
766: snes->usesksp = PETSC_TRUE;
767: snes->usesnpc = PETSC_FALSE;
769: PetscCall(SNESGetLineSearch(snes, &linesearch));
770: if (!((PetscObject)linesearch)->type_name) PetscCall(SNESLineSearchSetType(linesearch, SNESLINESEARCHBT));
771: PetscCall(SNESLineSearchBTSetAlpha(linesearch, 0.0));
773: snes->alwayscomputesfinalresidual = PETSC_TRUE;
775: PetscCall(SNESParametersInitialize(snes));
777: PetscCall(PetscNew(&vi));
778: snes->data = (void *)vi;
779: vi->checkredundancy = NULL;
781: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESVISetVariableBounds_C", SNESVISetVariableBounds_VI));
782: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESVISetComputeVariableBounds_C", SNESVISetComputeVariableBounds_VI));
783: PetscFunctionReturn(PETSC_SUCCESS);
784: }