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` and resets any function pointers the reduced-space `SNESVI` code composed onto it
241: Not Collective
243: Input Parameter:
244: . dm - the `DM` from which the VI context should be removed (may be `NULL`)
246: Level: developer
248: .seealso: `DM`, `SNESVINEWTONRSLS`, `SNESVISetVariableBounds()`, `PetscObjectCompose()`
249: @*/
250: PetscErrorCode DMDestroyVI(DM dm)
251: {
252: PetscFunctionBegin;
253: if (!dm) PetscFunctionReturn(PETSC_SUCCESS);
254: PetscCall(PetscObjectCompose((PetscObject)dm, "VI", (PetscObject)NULL));
255: PetscFunctionReturn(PETSC_SUCCESS);
256: }
258: /* Create active and inactive set vectors. The local size of this vector is set and PETSc computes the global size */
259: static PetscErrorCode SNESCreateSubVectors_VINEWTONRSLS(SNES snes, PetscInt n, Vec *newv)
260: {
261: Vec v;
263: PetscFunctionBegin;
264: PetscCall(VecCreate(PetscObjectComm((PetscObject)snes), &v));
265: PetscCall(VecSetSizes(v, n, PETSC_DECIDE));
266: PetscCall(VecSetType(v, VECSTANDARD));
267: *newv = v;
268: PetscFunctionReturn(PETSC_SUCCESS);
269: }
271: /* Resets the snes PC and KSP when the active set sizes change */
272: static PetscErrorCode SNESVIResetPCandKSP(SNES snes, Mat Amat, Mat Pmat)
273: {
274: KSP snesksp;
276: PetscFunctionBegin;
277: PetscCall(SNESGetKSP(snes, &snesksp));
278: PetscCall(KSPReset(snesksp));
279: PetscCall(KSPResetFromOptions(snesksp));
281: /*
282: KSP kspnew;
283: PC pcnew;
284: MatSolverType stype;
286: PetscCall(KSPCreate(PetscObjectComm((PetscObject)snes),&kspnew));
287: kspnew->pc_side = snesksp->pc_side;
288: kspnew->rtol = snesksp->rtol;
289: kspnew->abstol = snesksp->abstol;
290: kspnew->max_it = snesksp->max_it;
291: PetscCall(KSPSetType(kspnew,((PetscObject)snesksp)->type_name));
292: PetscCall(KSPGetPC(kspnew,&pcnew));
293: PetscCall(PCSetType(kspnew->pc,((PetscObject)snesksp->pc)->type_name));
294: PetscCall(PCSetOperators(kspnew->pc,Amat,Pmat));
295: PetscCall(PCFactorGetMatSolverType(snesksp->pc,&stype));
296: PetscCall(PCFactorSetMatSolverType(kspnew->pc,stype));
297: PetscCall(KSPDestroy(&snesksp));
298: snes->ksp = kspnew;
299: PetscCall(KSPSetFromOptions(kspnew));*/
300: PetscFunctionReturn(PETSC_SUCCESS);
301: }
303: /* Variational Inequality solver using reduce space method. No semismooth algorithm is
304: implemented in this algorithm. It basically identifies the active constraints and does
305: a linear solve on the other variables (those not associated with the active constraints). */
306: static PetscErrorCode SNESSolve_VINEWTONRSLS(SNES snes)
307: {
308: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
309: PetscInt maxits, i, lits;
310: SNESLineSearchReason lsreason;
311: PetscReal fnorm, gnorm, xnorm = 0, ynorm;
312: Vec Y, X, F;
313: KSPConvergedReason kspreason;
314: KSP ksp;
315: PC pc;
317: PetscFunctionBegin;
318: /* Multigrid must use Galerkin for coarse grids with active set/reduced space methods; cannot rediscretize on coarser grids*/
319: PetscCall(SNESGetKSP(snes, &ksp));
320: PetscCall(KSPGetPC(ksp, &pc));
321: PetscCall(PCMGSetGalerkin(pc, PC_MG_GALERKIN_BOTH));
323: snes->numFailures = 0;
324: snes->numLinearSolveFailures = 0;
325: snes->reason = SNES_CONVERGED_ITERATING;
327: maxits = snes->max_its; /* maximum number of iterations */
328: X = snes->vec_sol; /* solution vector */
329: F = snes->vec_func; /* residual vector */
330: Y = snes->work[0]; /* work vectors */
332: PetscCall(SNESLineSearchSetVIFunctions(snes->linesearch, SNESVIProjectOntoBounds, SNESVIComputeInactiveSetFnorm, SNESVIComputeInactiveSetFtY));
333: PetscCall(SNESLineSearchSetVecs(snes->linesearch, X, NULL, NULL, NULL, NULL));
334: PetscCall(SNESLineSearchSetUp(snes->linesearch));
336: PetscCall(PetscObjectSAWsTakeAccess((PetscObject)snes));
337: snes->iter = 0;
338: snes->norm = 0.0;
339: PetscCall(PetscObjectSAWsGrantAccess((PetscObject)snes));
341: PetscCall(SNESVIProjectOntoBounds(snes, X));
342: PetscCall(SNESComputeFunction(snes, X, F));
343: PetscCall(SNESVIComputeInactiveSetFnorm(snes, F, X, &fnorm));
344: PetscCall(VecNorm(X, NORM_2, &xnorm)); /* xnorm <- ||x|| */
345: SNESCheckFunctionDomainError(snes, fnorm);
346: PetscCall(PetscObjectSAWsTakeAccess((PetscObject)snes));
347: snes->norm = fnorm;
348: PetscCall(PetscObjectSAWsGrantAccess((PetscObject)snes));
349: PetscCall(SNESLogConvergenceHistory(snes, fnorm, 0));
351: /* test convergence */
352: PetscCall(SNESConverged(snes, 0, 0.0, 0.0, fnorm));
353: PetscCall(SNESMonitor(snes, 0, fnorm));
354: if (snes->reason) PetscFunctionReturn(PETSC_SUCCESS);
356: for (i = 0; i < maxits; i++) {
357: IS IS_act; /* _act -> active set _inact -> inactive set */
358: IS IS_redact; /* redundant active set */
359: VecScatter scat_act, scat_inact;
360: PetscInt nis_act, nis_inact;
361: Vec Y_act, Y_inact, F_inact;
362: Mat jac_inact_inact, prejac_inact_inact;
363: PetscBool isequal;
365: /* Call general purpose update function */
366: PetscTryTypeMethod(snes, update, snes->iter);
367: PetscCall(SNESComputeJacobian(snes, X, snes->jacobian, snes->jacobian_pre));
368: SNESCheckJacobianDomainError(snes);
370: /* Create active and inactive index sets */
372: /*original
373: PetscCall(SNESVICreateIndexSets_RS(snes,X,F,&IS_act,&vi->IS_inact));
374: */
375: PetscCall(SNESVIGetActiveSetIS(snes, X, F, &IS_act));
377: if (vi->checkredundancy) {
378: PetscCall((*vi->checkredundancy)(snes, IS_act, &IS_redact, vi->ctxP));
379: if (IS_redact) {
380: PetscCall(ISSort(IS_redact));
381: PetscCall(ISComplement(IS_redact, X->map->rstart, X->map->rend, &vi->IS_inact));
382: PetscCall(ISDestroy(&IS_redact));
383: } else {
384: PetscCall(ISComplement(IS_act, X->map->rstart, X->map->rend, &vi->IS_inact));
385: }
386: } else {
387: PetscCall(ISComplement(IS_act, X->map->rstart, X->map->rend, &vi->IS_inact));
388: }
390: /* Create inactive set submatrix */
391: PetscCall(MatCreateSubMatrix(snes->jacobian, vi->IS_inact, vi->IS_inact, MAT_INITIAL_MATRIX, &jac_inact_inact));
393: if (0) { /* Dead code (temporary developer hack) */
394: IS keptrows;
395: PetscCall(MatFindNonzeroRows(jac_inact_inact, &keptrows));
396: if (keptrows) {
397: PetscInt cnt, *nrows, k;
398: const PetscInt *krows, *inact;
399: PetscInt rstart;
401: PetscCall(MatGetOwnershipRange(jac_inact_inact, &rstart, NULL));
402: PetscCall(MatDestroy(&jac_inact_inact));
403: PetscCall(ISDestroy(&IS_act));
405: PetscCall(ISGetLocalSize(keptrows, &cnt));
406: PetscCall(ISGetIndices(keptrows, &krows));
407: PetscCall(ISGetIndices(vi->IS_inact, &inact));
408: PetscCall(PetscMalloc1(cnt, &nrows));
409: for (k = 0; k < cnt; k++) nrows[k] = inact[krows[k] - rstart];
410: PetscCall(ISRestoreIndices(keptrows, &krows));
411: PetscCall(ISRestoreIndices(vi->IS_inact, &inact));
412: PetscCall(ISDestroy(&keptrows));
413: PetscCall(ISDestroy(&vi->IS_inact));
415: PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)snes), cnt, nrows, PETSC_OWN_POINTER, &vi->IS_inact));
416: PetscCall(ISComplement(vi->IS_inact, F->map->rstart, F->map->rend, &IS_act));
417: PetscCall(MatCreateSubMatrix(snes->jacobian, vi->IS_inact, vi->IS_inact, MAT_INITIAL_MATRIX, &jac_inact_inact));
418: }
419: }
420: PetscCall(DMSetVI(snes->dm, vi->IS_inact));
421: /* remove later */
423: /*
424: PetscCall(VecView(vi->xu,PETSC_VIEWER_BINARY_(((PetscObject)vi->xu)->comm)));
425: PetscCall(VecView(vi->xl,PETSC_VIEWER_BINARY_(((PetscObject)vi->xl)->comm)));
426: PetscCall(VecView(X,PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)X))));
427: PetscCall(VecView(F,PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)F))));
428: PetscCall(ISView(vi->IS_inact,PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)vi->IS_inact))));
429: */
431: /* Get sizes of active and inactive sets */
432: PetscCall(ISGetLocalSize(IS_act, &nis_act));
433: PetscCall(ISGetLocalSize(vi->IS_inact, &nis_inact));
435: /* Create active and inactive set vectors */
436: PetscCall(SNESCreateSubVectors_VINEWTONRSLS(snes, nis_inact, &F_inact));
437: PetscCall(SNESCreateSubVectors_VINEWTONRSLS(snes, nis_act, &Y_act));
438: PetscCall(SNESCreateSubVectors_VINEWTONRSLS(snes, nis_inact, &Y_inact));
440: /* Create scatter contexts */
441: PetscCall(VecScatterCreate(Y, IS_act, Y_act, NULL, &scat_act));
442: PetscCall(VecScatterCreate(Y, vi->IS_inact, Y_inact, NULL, &scat_inact));
444: /* Do a vec scatter to active and inactive set vectors */
445: PetscCall(VecScatterBegin(scat_inact, F, F_inact, INSERT_VALUES, SCATTER_FORWARD));
446: PetscCall(VecScatterEnd(scat_inact, F, F_inact, INSERT_VALUES, SCATTER_FORWARD));
448: PetscCall(VecScatterBegin(scat_act, Y, Y_act, INSERT_VALUES, SCATTER_FORWARD));
449: PetscCall(VecScatterEnd(scat_act, Y, Y_act, INSERT_VALUES, SCATTER_FORWARD));
451: PetscCall(VecScatterBegin(scat_inact, Y, Y_inact, INSERT_VALUES, SCATTER_FORWARD));
452: PetscCall(VecScatterEnd(scat_inact, Y, Y_inact, INSERT_VALUES, SCATTER_FORWARD));
454: /* Active set direction = 0 */
455: PetscCall(VecSet(Y_act, 0));
456: if (snes->jacobian != snes->jacobian_pre) PetscCall(MatCreateSubMatrix(snes->jacobian_pre, vi->IS_inact, vi->IS_inact, MAT_INITIAL_MATRIX, &prejac_inact_inact));
457: else prejac_inact_inact = jac_inact_inact;
459: PetscCall(ISEqual(vi->IS_inact_prev, vi->IS_inact, &isequal));
460: if (!isequal) {
461: PetscCall(SNESVIResetPCandKSP(snes, jac_inact_inact, prejac_inact_inact));
462: PetscCall(PCFieldSplitRestrictIS(pc, vi->IS_inact));
463: }
465: /* PetscCall(ISView(vi->IS_inact,0)); */
466: /* PetscCall(ISView(IS_act,0));*/
467: /* ierr = MatView(snes->jacobian_pre,0); */
469: PetscCall(KSPSetOperators(snes->ksp, jac_inact_inact, prejac_inact_inact));
470: PetscCall(KSPSetUp(snes->ksp));
471: {
472: PC pc;
473: PetscBool flg;
474: PetscCall(KSPGetPC(snes->ksp, &pc));
475: PetscCall(PetscObjectTypeCompare((PetscObject)pc, PCFIELDSPLIT, &flg));
476: if (flg) {
477: KSP *subksps;
478: PetscCall(PCFieldSplitGetSubKSP(pc, NULL, &subksps));
479: PetscCall(KSPGetPC(subksps[0], &pc));
480: PetscCall(PetscFree(subksps));
481: PetscCall(PetscObjectTypeCompare((PetscObject)pc, PCBJACOBI, &flg));
482: if (flg) {
483: PetscInt n, N = 101 * 101, j, cnts[3] = {0, 0, 0};
484: const PetscInt *ii;
486: PetscCall(ISGetSize(vi->IS_inact, &n));
487: PetscCall(ISGetIndices(vi->IS_inact, &ii));
488: for (j = 0; j < n; j++) {
489: if (ii[j] < N) cnts[0]++;
490: else if (ii[j] < 2 * N) cnts[1]++;
491: else if (ii[j] < 3 * N) cnts[2]++;
492: }
493: PetscCall(ISRestoreIndices(vi->IS_inact, &ii));
495: PetscCall(PCBJacobiSetTotalBlocks(pc, 3, cnts));
496: }
497: }
498: }
500: PetscCall(KSPSolve(snes->ksp, F_inact, Y_inact));
501: PetscCall(VecScatterBegin(scat_act, Y_act, Y, INSERT_VALUES, SCATTER_REVERSE));
502: PetscCall(VecScatterEnd(scat_act, Y_act, Y, INSERT_VALUES, SCATTER_REVERSE));
503: PetscCall(VecScatterBegin(scat_inact, Y_inact, Y, INSERT_VALUES, SCATTER_REVERSE));
504: PetscCall(VecScatterEnd(scat_inact, Y_inact, Y, INSERT_VALUES, SCATTER_REVERSE));
506: PetscCall(VecDestroy(&F_inact));
507: PetscCall(VecDestroy(&Y_act));
508: PetscCall(VecDestroy(&Y_inact));
509: PetscCall(VecScatterDestroy(&scat_act));
510: PetscCall(VecScatterDestroy(&scat_inact));
511: PetscCall(ISDestroy(&IS_act));
512: if (!isequal) {
513: PetscCall(ISDestroy(&vi->IS_inact_prev));
514: PetscCall(ISDuplicate(vi->IS_inact, &vi->IS_inact_prev));
515: }
516: PetscCall(ISDestroy(&vi->IS_inact));
517: PetscCall(MatDestroy(&jac_inact_inact));
518: if (snes->jacobian != snes->jacobian_pre) PetscCall(MatDestroy(&prejac_inact_inact));
520: PetscCall(KSPGetConvergedReason(snes->ksp, &kspreason));
521: if (kspreason < 0) {
522: if (++snes->numLinearSolveFailures >= snes->maxLinearSolveFailures) {
523: PetscCall(PetscInfo(snes, "iter=%" PetscInt_FMT ", number linear solve failures %" PetscInt_FMT " greater than current SNES allowed, stopping solve\n", snes->iter, snes->numLinearSolveFailures));
524: snes->reason = SNES_DIVERGED_LINEAR_SOLVE;
525: break;
526: }
527: }
529: PetscCall(KSPGetIterationNumber(snes->ksp, &lits));
530: snes->linear_its += lits;
531: PetscCall(PetscInfo(snes, "iter=%" PetscInt_FMT ", linear solve iterations=%" PetscInt_FMT "\n", snes->iter, lits));
532: /*
533: if (snes->ops->precheck) {
534: PetscBool changed_y = PETSC_FALSE;
535: PetscUseTypeMethod(snes,precheck ,X,Y,snes->precheck,&changed_y);
536: }
538: if (PetscLogPrintInfo) PetscCall(SNESVICheckResidual_Private(snes,snes->jacobian,F,Y,G,W));
539: */
540: /* Compute a (scaled) negative update in the line search routine:
541: Y <- X - lambda*Y
542: and evaluate G = function(Y) (depends on the line search).
543: */
544: PetscCall(VecCopy(Y, snes->vec_sol_update));
545: ynorm = 1;
546: gnorm = fnorm;
547: PetscCall(SNESLineSearchApply(snes->linesearch, X, F, &gnorm, Y));
548: PetscCall(DMDestroyVI(snes->dm));
549: if (snes->reason) break;
550: PetscCall(SNESLineSearchGetReason(snes->linesearch, &lsreason));
551: if (lsreason) {
552: if (snes->stol * xnorm > ynorm) {
553: snes->reason = SNES_CONVERGED_SNORM_RELATIVE;
554: break;
555: } else if (lsreason == SNES_LINESEARCH_FAILED_FUNCTION_DOMAIN) {
556: snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
557: break;
558: } else if (lsreason == SNES_LINESEARCH_FAILED_NANORINF) {
559: snes->reason = SNES_DIVERGED_FUNCTION_NANORINF;
560: break;
561: } else if (lsreason == SNES_LINESEARCH_FAILED_OBJECTIVE_DOMAIN) {
562: snes->reason = SNES_DIVERGED_OBJECTIVE_DOMAIN;
563: break;
564: } else if (lsreason == SNES_LINESEARCH_FAILED_JACOBIAN_DOMAIN) {
565: snes->reason = SNES_DIVERGED_JACOBIAN_DOMAIN;
566: break;
567: } else if (++snes->numFailures >= snes->maxFailures) {
568: PetscBool ismin;
570: snes->reason = SNES_DIVERGED_LINE_SEARCH;
571: PetscCall(SNESVICheckLocalMin_Private(snes, snes->jacobian, F, X, gnorm, &ismin));
572: if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN;
573: break;
574: }
575: }
576: PetscCall(SNESLineSearchGetNorms(snes->linesearch, &xnorm, &gnorm, &ynorm));
577: PetscCall(PetscInfo(snes, "fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n", (double)fnorm, (double)gnorm, (double)ynorm, (int)lsreason));
578: /* Update function and solution vectors */
579: fnorm = gnorm;
580: /* Monitor convergence */
581: PetscCall(PetscObjectSAWsTakeAccess((PetscObject)snes));
582: snes->iter = i + 1;
583: snes->norm = fnorm;
584: snes->xnorm = xnorm;
585: snes->ynorm = ynorm;
586: PetscCall(PetscObjectSAWsGrantAccess((PetscObject)snes));
587: PetscCall(SNESLogConvergenceHistory(snes, snes->norm, lits));
588: /* Test for convergence, xnorm = || X || */
589: if (snes->ops->converged != SNESConvergedSkip) PetscCall(VecNorm(X, NORM_2, &xnorm));
590: PetscCall(SNESConverged(snes, snes->iter, xnorm, ynorm, fnorm));
591: PetscCall(SNESMonitor(snes, snes->iter, snes->norm));
592: if (snes->reason) break;
593: }
594: /* 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 */
595: PetscCall(DMDestroyVI(snes->dm));
596: PetscFunctionReturn(PETSC_SUCCESS);
597: }
599: /*@C
600: SNESVISetRedundancyCheck - Provide a function to check for any redundancy in the VI active set
602: Logically Collective
604: Input Parameters:
605: + snes - the `SNESVINEWTONRSLS` context
606: . func - the function to check of redundancies
607: - ctx - optional context used by the function
609: Calling sequence of func:
610: + snes - the `SNES` context
611: . is_act - the set of points in the active sets
612: . is_redact - output, the set of points in the non-redundant active set
613: - ctx - optional context
615: Level: advanced
617: Note:
618: Sometimes the inactive set will result in a singular sub-Jacobian problem that needs to be solved, this allows the user,
619: when they know more about their specific problem to provide a function that removes the redundancy that results in the singular linear system
621: See `SNESVINEWTONRSLS` for a concise description of the active and inactive sets
623: .seealso: [](ch_snes), `SNES`, `SNESVINEWTONRSLS`, `SNESVIGetInactiveSet()`, `DMSetVI()`
624: @*/
625: PetscErrorCode SNESVISetRedundancyCheck(SNES snes, PetscErrorCode (*func)(SNES snes, IS is_act, IS *is_redact, PetscCtx ctx), PetscCtx ctx)
626: {
627: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
629: PetscFunctionBegin;
631: vi->checkredundancy = func;
632: vi->ctxP = ctx;
633: PetscFunctionReturn(PETSC_SUCCESS);
634: }
636: #if PetscDefined(HAVE_MATLAB)
637: #include <engine.h>
638: #include <mex.h>
639: typedef struct {
640: char *funcname;
641: mxArray *ctx;
642: } SNESMatlabContext;
644: PetscErrorCode SNESVIRedundancyCheck_Matlab(SNES snes, IS is_act, IS *is_redact, PetscCtx ctx)
645: {
646: SNESMatlabContext *sctx = (SNESMatlabContext *)ctx;
647: int nlhs = 1, nrhs = 5;
648: mxArray *plhs[1], *prhs[5];
649: long long int l1 = 0, l2 = 0, ls = 0;
650: PetscInt *indices = NULL;
652: PetscFunctionBegin;
655: PetscAssertPointer(is_redact, 3);
656: PetscCheckSameComm(snes, 1, is_act, 2);
658: /* Create IS for reduced active set of size 0, its size and indices will
659: bet set by the MATLAB function */
660: PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)snes), 0, indices, PETSC_OWN_POINTER, is_redact));
661: /* call MATLAB function in ctx */
662: PetscCall(PetscArraycpy(&ls, &snes, 1));
663: PetscCall(PetscArraycpy(&l1, &is_act, 1));
664: PetscCall(PetscArraycpy(&l2, is_redact, 1));
665: prhs[0] = mxCreateDoubleScalar((double)ls);
666: prhs[1] = mxCreateDoubleScalar((double)l1);
667: prhs[2] = mxCreateDoubleScalar((double)l2);
668: prhs[3] = mxCreateString(sctx->funcname);
669: prhs[4] = sctx->ctx;
670: PetscCall(mexCallMATLAB(nlhs, plhs, nrhs, prhs, "PetscSNESVIRedundancyCheckInternal"));
671: PetscCall(mxGetScalar(plhs[0]));
672: mxDestroyArray(prhs[0]);
673: mxDestroyArray(prhs[1]);
674: mxDestroyArray(prhs[2]);
675: mxDestroyArray(prhs[3]);
676: mxDestroyArray(plhs[0]);
677: PetscFunctionReturn(PETSC_SUCCESS);
678: }
680: PetscErrorCode SNESVISetRedundancyCheckMatlab(SNES snes, const char *func, mxArray *ctx)
681: {
682: SNESMatlabContext *sctx;
684: PetscFunctionBegin;
685: /* currently sctx is memory bleed */
686: PetscCall(PetscNew(&sctx));
687: PetscCall(PetscStrallocpy(func, &sctx->funcname));
688: sctx->ctx = mxDuplicateArray(ctx);
689: PetscCall(SNESVISetRedundancyCheck(snes, SNESVIRedundancyCheck_Matlab, sctx));
690: PetscFunctionReturn(PETSC_SUCCESS);
691: }
693: #endif
695: static PetscErrorCode SNESSetUp_VINEWTONRSLS(SNES snes)
696: {
697: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
698: PetscInt *indices;
699: PetscInt i, n, rstart, rend;
700: SNESLineSearch linesearch;
702: PetscFunctionBegin;
703: PetscCall(SNESSetUp_VI(snes));
705: /* Set up previous active index set for the first snes solve
706: vi->IS_inact_prev = 0,1,2,....N */
708: PetscCall(VecGetOwnershipRange(snes->work[0], &rstart, &rend));
709: PetscCall(VecGetLocalSize(snes->work[0], &n));
710: PetscCall(PetscMalloc1(n, &indices));
711: for (i = 0; i < n; i++) indices[i] = rstart + i;
712: PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)snes), n, indices, PETSC_OWN_POINTER, &vi->IS_inact_prev));
714: /* set the line search functions */
715: if (!snes->linesearch) {
716: PetscCall(SNESGetLineSearch(snes, &linesearch));
717: PetscCall(SNESLineSearchSetType(linesearch, SNESLINESEARCHBT));
718: }
719: PetscFunctionReturn(PETSC_SUCCESS);
720: }
722: static PetscErrorCode SNESReset_VINEWTONRSLS(SNES snes)
723: {
724: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
726: PetscFunctionBegin;
727: PetscCall(SNESReset_VI(snes));
728: PetscCall(ISDestroy(&vi->IS_inact_prev));
729: PetscFunctionReturn(PETSC_SUCCESS);
730: }
732: /*MC
733: SNESVINEWTONRSLS - Reduced space active set solvers for variational inequalities based on Newton's method
735: Options Database Keys:
736: + -snes_type (vinewtonssls|vinewtonrsls) - A semi-smooth solver or a reduced space active set method
737: . -snes_vi_zero_tolerance - Tolerance for considering $u_i$ value to be on a bound.
738: . -snes_vi_monitor - Prints the number of active constraints (inactive set points) at each iteration.
739: . -snes_vi_monitor_residual - View the residual vector at each iteration, using zero for active constraints (i.e. the inactive variables).
740: - -snes_vi_monitor_active - View the active set by outputting a one for vector components in the active set and zero for the inactive.
742: Level: beginner
744: Note:
745: Reduced-space (active set methods) work as follows at each iteration\:
746: - 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
747: 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
748: the upper bound $u_i = U_i$ with also $[F(u)]_i \le 0.$
749: - 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
750: from both the rows and columns.
751: - A line search is then used to update the active variables (the inactive set of variables are not changed).
753: 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
754: 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.
756: See {cite}`benson2006flexible`
758: .seealso: [](ch_snes), `SNESVISetVariableBounds()`, `SNESVISetComputeVariableBounds()`, `SNESCreate()`, `SNES`, `SNESSetType()`, `SNESVINEWTONSSLS`, `SNESNEWTONTR`, `SNESLineSearchSetType()`, `SNESLineSearchSetPostCheck()`, `SNESLineSearchSetPreCheck()`, `SNESVIGetInactiveSet()`, `DMSetVI()`, `SNESVISetRedundancyCheck()`
759: M*/
760: PETSC_EXTERN PetscErrorCode SNESCreate_VINEWTONRSLS(SNES snes)
761: {
762: SNES_VINEWTONRSLS *vi;
763: SNESLineSearch linesearch;
765: PetscFunctionBegin;
766: snes->ops->reset = SNESReset_VINEWTONRSLS;
767: snes->ops->setup = SNESSetUp_VINEWTONRSLS;
768: snes->ops->solve = SNESSolve_VINEWTONRSLS;
769: snes->ops->destroy = SNESDestroy_VI;
770: snes->ops->setfromoptions = SNESSetFromOptions_VI;
771: snes->ops->view = NULL;
772: if (!snes->ops->converged || snes->ops->converged == SNESConvergedDefault) snes->ops->converged = SNESConvergedDefault_VI;
774: snes->usesksp = PETSC_TRUE;
775: snes->usesnpc = PETSC_FALSE;
777: PetscCall(SNESGetLineSearch(snes, &linesearch));
778: if (!((PetscObject)linesearch)->type_name) PetscCall(SNESLineSearchSetType(linesearch, SNESLINESEARCHBT));
779: PetscCall(SNESLineSearchBTSetAlpha(linesearch, 0.0));
781: snes->alwayscomputesfinalresidual = PETSC_TRUE;
783: PetscCall(PetscNew(&vi));
784: snes->data = (void *)vi;
786: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESVISetVariableBounds_C", SNESVISetVariableBounds_VI));
787: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESVISetComputeVariableBounds_C", SNESVISetComputeVariableBounds_VI));
788: PetscFunctionReturn(PETSC_SUCCESS);
789: }