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: PetscCall(VecSet(finemarked, 0.0));
131: for (k = 0; k < n; k++) PetscCall(VecSetValue(finemarked, index[k], 1.0, INSERT_VALUES));
132: PetscCall(VecAssemblyBegin(finemarked));
133: PetscCall(VecAssemblyEnd(finemarked));
135: PetscCall(DMCreateInjection(*dm2, dm1, &inject));
136: PetscCall(MatRestrict(inject, finemarked, coarsemarked));
137: PetscCall(MatDestroy(&inject));
139: /*
140: create index set list of coarse inactive points from coarsemarked
141: */
142: PetscCall(VecGetLocalSize(coarsemarked, &n));
143: PetscCall(VecGetOwnershipRange(coarsemarked, &rstart, NULL));
144: PetscCall(VecGetArray(coarsemarked, &marked));
145: for (k = 0; k < n; k++) {
146: if (marked[k] != 0.0) cnt++;
147: }
148: PetscCall(PetscMalloc1(cnt, &coarseindex));
149: cnt = 0;
150: for (k = 0; k < n; k++) {
151: if (marked[k] != 0.0) coarseindex[cnt++] = k + rstart;
152: }
153: PetscCall(VecRestoreArray(coarsemarked, &marked));
154: PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)coarsemarked), cnt, coarseindex, PETSC_OWN_POINTER, &inactive));
156: PetscCall(DMClearGlobalVectors(dm1));
158: dm1->ops->createglobalvector = DMCreateGlobalVector_SNESVI;
160: PetscCall(DMSetVI(*dm2, inactive));
162: PetscCall(VecDestroy(&finemarked));
163: PetscCall(VecDestroy(&coarsemarked));
164: PetscCall(ISDestroy(&inactive));
165: PetscFunctionReturn(PETSC_SUCCESS);
166: }
168: static PetscErrorCode DMDestroy_SNESVI(PetscCtxRt ctx)
169: {
170: DM_SNESVI *dmsnesvi = *(DM_SNESVI **)ctx;
172: PetscFunctionBegin;
173: /* reset the base methods in the DM object that were changed when the DM_SNESVI was reset */
174: dmsnesvi->dm->ops->createinterpolation = dmsnesvi->createinterpolation;
175: dmsnesvi->dm->ops->coarsen = dmsnesvi->coarsen;
176: dmsnesvi->dm->ops->createglobalvector = dmsnesvi->createglobalvector;
177: dmsnesvi->dm->ops->createinjection = dmsnesvi->createinjection;
178: dmsnesvi->dm->ops->hascreateinjection = dmsnesvi->hascreateinjection;
179: /* need to clear out this vectors because some of them may not have a reference to the DM
180: but they are counted as having references to the DM in DMDestroy() */
181: PetscCall(DMClearGlobalVectors(dmsnesvi->dm));
183: PetscCall(ISDestroy(&dmsnesvi->inactive));
184: PetscCall(PetscFree(dmsnesvi));
185: PetscFunctionReturn(PETSC_SUCCESS);
186: }
188: /*@
189: DMSetVI - Marks a `DM` as associated with a VI problem. This causes the interpolation/restriction operators to
190: be restricted to only those variables NOT associated with active constraints.
192: Logically Collective
194: Input Parameters:
195: + dm - the `DM` object
196: - inactive - an `IS` indicating which points are currently not active
198: Level: intermediate
200: .seealso: [](ch_snes), `SNES`, `SNESVINEWTONRSLS`, `SNESVIGetInactiveSet()`
201: @*/
202: PetscErrorCode DMSetVI(DM dm, IS inactive)
203: {
204: PetscContainer isnes;
205: DM_SNESVI *dmsnesvi;
207: PetscFunctionBegin;
208: if (!dm) PetscFunctionReturn(PETSC_SUCCESS);
210: PetscCall(PetscObjectReference((PetscObject)inactive));
212: PetscCall(PetscObjectQuery((PetscObject)dm, "VI", (PetscObject *)&isnes));
213: if (!isnes) {
214: PetscCall(PetscNew(&dmsnesvi));
215: PetscCall(PetscObjectContainerCompose((PetscObject)dm, "VI", dmsnesvi, DMDestroy_SNESVI));
217: dmsnesvi->createinterpolation = dm->ops->createinterpolation;
218: dm->ops->createinterpolation = DMCreateInterpolation_SNESVI;
219: dmsnesvi->coarsen = dm->ops->coarsen;
220: dm->ops->coarsen = DMCoarsen_SNESVI;
221: dmsnesvi->createglobalvector = dm->ops->createglobalvector;
222: dm->ops->createglobalvector = DMCreateGlobalVector_SNESVI;
223: dmsnesvi->createinjection = dm->ops->createinjection;
224: dm->ops->createinjection = NULL;
225: dmsnesvi->hascreateinjection = dm->ops->hascreateinjection;
226: dm->ops->hascreateinjection = NULL;
227: } else {
228: PetscCall(PetscContainerGetPointer(isnes, &dmsnesvi));
229: PetscCall(ISDestroy(&dmsnesvi->inactive));
230: }
231: PetscCall(DMClearGlobalVectors(dm));
232: PetscCall(ISGetLocalSize(inactive, &dmsnesvi->n));
234: dmsnesvi->inactive = inactive;
235: dmsnesvi->dm = dm;
236: PetscFunctionReturn(PETSC_SUCCESS);
237: }
239: /*@
240: DMDestroyVI - Frees the `DM_SNESVI` object contained in the `DM` and resets any function pointers the reduced-space `SNESVI` code composed onto it
242: Not Collective
244: Input Parameter:
245: . dm - the `DM` from which the VI context should be removed (may be `NULL`)
247: Level: developer
249: .seealso: `DM`, `SNESVINEWTONRSLS`, `SNESVISetVariableBounds()`, `PetscObjectCompose()`
250: @*/
251: PetscErrorCode DMDestroyVI(DM dm)
252: {
253: PetscFunctionBegin;
254: if (!dm) PetscFunctionReturn(PETSC_SUCCESS);
255: PetscCall(PetscObjectCompose((PetscObject)dm, "VI", (PetscObject)NULL));
256: PetscFunctionReturn(PETSC_SUCCESS);
257: }
259: /* Create active and inactive set vectors. The local size of this vector is set and PETSc computes the global size */
260: static PetscErrorCode SNESCreateSubVectors_VINEWTONRSLS(SNES snes, PetscInt n, Vec *newv)
261: {
262: Vec v;
264: PetscFunctionBegin;
265: PetscCall(VecCreate(PetscObjectComm((PetscObject)snes), &v));
266: PetscCall(VecSetSizes(v, n, PETSC_DECIDE));
267: PetscCall(VecSetType(v, VECSTANDARD));
268: *newv = v;
269: PetscFunctionReturn(PETSC_SUCCESS);
270: }
272: /* Resets the snes PC and KSP when the active set sizes change */
273: static PetscErrorCode SNESVIResetPCandKSP(SNES snes, Mat Amat, Mat Pmat)
274: {
275: KSP snesksp;
277: PetscFunctionBegin;
278: PetscCall(SNESGetKSP(snes, &snesksp));
279: PetscCall(KSPReset(snesksp));
280: PetscCall(KSPResetFromOptions(snesksp));
282: /*
283: KSP kspnew;
284: PC pcnew;
285: MatSolverType stype;
287: PetscCall(KSPCreate(PetscObjectComm((PetscObject)snes),&kspnew));
288: kspnew->pc_side = snesksp->pc_side;
289: kspnew->rtol = snesksp->rtol;
290: kspnew->abstol = snesksp->abstol;
291: kspnew->max_it = snesksp->max_it;
292: PetscCall(KSPSetType(kspnew,((PetscObject)snesksp)->type_name));
293: PetscCall(KSPGetPC(kspnew,&pcnew));
294: PetscCall(PCSetType(kspnew->pc,((PetscObject)snesksp->pc)->type_name));
295: PetscCall(PCSetOperators(kspnew->pc,Amat,Pmat));
296: PetscCall(PCFactorGetMatSolverType(snesksp->pc,&stype));
297: PetscCall(PCFactorSetMatSolverType(kspnew->pc,stype));
298: PetscCall(KSPDestroy(&snesksp));
299: snes->ksp = kspnew;
300: PetscCall(KSPSetFromOptions(kspnew));*/
301: PetscFunctionReturn(PETSC_SUCCESS);
302: }
304: /* Variational Inequality solver using reduce space method. No semismooth algorithm is
305: implemented in this algorithm. It basically identifies the active constraints and does
306: a linear solve on the other variables (those not associated with the active constraints). */
307: static PetscErrorCode SNESSolve_VINEWTONRSLS(SNES snes)
308: {
309: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
310: PetscInt maxits, i, lits;
311: SNESLineSearchReason lsreason;
312: PetscReal fnorm, gnorm, xnorm = 0, ynorm;
313: Vec Y, X, F;
314: KSPConvergedReason kspreason;
315: KSP ksp;
316: PC pc;
318: PetscFunctionBegin;
319: /* Multigrid must use Galerkin for coarse grids with active set/reduced space methods; cannot rediscretize on coarser grids*/
320: PetscCall(SNESGetKSP(snes, &ksp));
321: PetscCall(KSPGetPC(ksp, &pc));
322: PetscCall(PCMGSetGalerkin(pc, PC_MG_GALERKIN_BOTH));
324: snes->numFailures = 0;
325: snes->numLinearSolveFailures = 0;
326: snes->reason = SNES_CONVERGED_ITERATING;
328: maxits = snes->max_its; /* maximum number of iterations */
329: X = snes->vec_sol; /* solution vector */
330: F = snes->vec_func; /* residual vector */
331: Y = snes->work[0]; /* work vectors */
333: PetscCall(SNESLineSearchSetVIFunctions(snes->linesearch, SNESVIProjectOntoBounds, SNESVIComputeInactiveSetFnorm, SNESVIComputeInactiveSetFtY));
334: PetscCall(SNESLineSearchSetVecs(snes->linesearch, X, NULL, NULL, NULL, NULL));
335: PetscCall(SNESLineSearchSetUp(snes->linesearch));
337: PetscCall(PetscObjectSAWsTakeAccess((PetscObject)snes));
338: snes->iter = 0;
339: snes->norm = 0.0;
340: PetscCall(PetscObjectSAWsGrantAccess((PetscObject)snes));
342: PetscCall(SNESVIProjectOntoBounds(snes, X));
343: PetscCall(SNESComputeFunction(snes, X, F));
344: PetscCall(SNESVIComputeInactiveSetFnorm(snes, F, X, &fnorm));
345: PetscCall(VecNorm(X, NORM_2, &xnorm)); /* xnorm <- ||x|| */
346: SNESCheckFunctionDomainError(snes, fnorm);
347: PetscCall(PetscObjectSAWsTakeAccess((PetscObject)snes));
348: snes->norm = fnorm;
349: PetscCall(PetscObjectSAWsGrantAccess((PetscObject)snes));
350: PetscCall(SNESLogConvergenceHistory(snes, fnorm, 0));
352: /* test convergence */
353: PetscCall(SNESConverged(snes, 0, 0.0, 0.0, fnorm));
354: PetscCall(SNESMonitor(snes, 0, fnorm));
355: if (snes->reason) PetscFunctionReturn(PETSC_SUCCESS);
357: for (i = 0; i < maxits; i++) {
358: IS IS_act; /* _act -> active set _inact -> inactive set */
359: IS IS_redact; /* redundant active set */
360: VecScatter scat_act, scat_inact;
361: PetscInt nis_act, nis_inact;
362: Vec Y_act, Y_inact, F_inact;
363: Mat jac_inact_inact, prejac_inact_inact;
364: PetscBool isequal;
366: /* Call general purpose update function */
367: PetscTryTypeMethod(snes, update, snes->iter);
368: PetscCall(SNESComputeJacobian(snes, X, snes->jacobian, snes->jacobian_pre));
369: SNESCheckJacobianDomainError(snes);
371: /* Create active and inactive index sets */
373: /*original
374: PetscCall(SNESVICreateIndexSets_RS(snes,X,F,&IS_act,&vi->IS_inact));
375: */
376: PetscCall(SNESVIGetActiveSetIS(snes, X, F, &IS_act));
378: if (vi->checkredundancy) {
379: PetscCall((*vi->checkredundancy)(snes, IS_act, &IS_redact, vi->ctxP));
380: if (IS_redact) {
381: PetscCall(ISSort(IS_redact));
382: PetscCall(ISComplement(IS_redact, X->map->rstart, X->map->rend, &vi->IS_inact));
383: PetscCall(ISDestroy(&IS_redact));
384: } else {
385: PetscCall(ISComplement(IS_act, X->map->rstart, X->map->rend, &vi->IS_inact));
386: }
387: } else {
388: PetscCall(ISComplement(IS_act, X->map->rstart, X->map->rend, &vi->IS_inact));
389: }
391: /* Create inactive set submatrix */
392: PetscCall(MatCreateSubMatrix(snes->jacobian, vi->IS_inact, vi->IS_inact, MAT_INITIAL_MATRIX, &jac_inact_inact));
394: if (0) { /* Dead code (temporary developer hack) */
395: IS keptrows;
396: PetscCall(MatFindNonzeroRows(jac_inact_inact, &keptrows));
397: if (keptrows) {
398: PetscInt cnt, *nrows, k;
399: const PetscInt *krows, *inact;
400: PetscInt rstart;
402: PetscCall(MatGetOwnershipRange(jac_inact_inact, &rstart, NULL));
403: PetscCall(MatDestroy(&jac_inact_inact));
404: PetscCall(ISDestroy(&IS_act));
406: PetscCall(ISGetLocalSize(keptrows, &cnt));
407: PetscCall(ISGetIndices(keptrows, &krows));
408: PetscCall(ISGetIndices(vi->IS_inact, &inact));
409: PetscCall(PetscMalloc1(cnt, &nrows));
410: for (k = 0; k < cnt; k++) nrows[k] = inact[krows[k] - rstart];
411: PetscCall(ISRestoreIndices(keptrows, &krows));
412: PetscCall(ISRestoreIndices(vi->IS_inact, &inact));
413: PetscCall(ISDestroy(&keptrows));
414: PetscCall(ISDestroy(&vi->IS_inact));
416: PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)snes), cnt, nrows, PETSC_OWN_POINTER, &vi->IS_inact));
417: PetscCall(ISComplement(vi->IS_inact, F->map->rstart, F->map->rend, &IS_act));
418: PetscCall(MatCreateSubMatrix(snes->jacobian, vi->IS_inact, vi->IS_inact, MAT_INITIAL_MATRIX, &jac_inact_inact));
419: }
420: }
421: PetscCall(DMSetVI(snes->dm, vi->IS_inact));
422: /* remove later */
424: /*
425: PetscCall(VecView(vi->xu,PETSC_VIEWER_BINARY_(((PetscObject)vi->xu)->comm)));
426: PetscCall(VecView(vi->xl,PETSC_VIEWER_BINARY_(((PetscObject)vi->xl)->comm)));
427: PetscCall(VecView(X,PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)X))));
428: PetscCall(VecView(F,PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)F))));
429: PetscCall(ISView(vi->IS_inact,PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)vi->IS_inact))));
430: */
432: /* Get sizes of active and inactive sets */
433: PetscCall(ISGetLocalSize(IS_act, &nis_act));
434: PetscCall(ISGetLocalSize(vi->IS_inact, &nis_inact));
436: /* Create active and inactive set vectors */
437: PetscCall(SNESCreateSubVectors_VINEWTONRSLS(snes, nis_inact, &F_inact));
438: PetscCall(SNESCreateSubVectors_VINEWTONRSLS(snes, nis_act, &Y_act));
439: PetscCall(SNESCreateSubVectors_VINEWTONRSLS(snes, nis_inact, &Y_inact));
441: /* Create scatter contexts */
442: PetscCall(VecScatterCreate(Y, IS_act, Y_act, NULL, &scat_act));
443: PetscCall(VecScatterCreate(Y, vi->IS_inact, Y_inact, NULL, &scat_inact));
445: /* Do a vec scatter to active and inactive set vectors */
446: PetscCall(VecScatterBegin(scat_inact, F, F_inact, INSERT_VALUES, SCATTER_FORWARD));
447: PetscCall(VecScatterEnd(scat_inact, F, F_inact, INSERT_VALUES, SCATTER_FORWARD));
449: PetscCall(VecScatterBegin(scat_act, Y, Y_act, INSERT_VALUES, SCATTER_FORWARD));
450: PetscCall(VecScatterEnd(scat_act, Y, Y_act, INSERT_VALUES, SCATTER_FORWARD));
452: PetscCall(VecScatterBegin(scat_inact, Y, Y_inact, INSERT_VALUES, SCATTER_FORWARD));
453: PetscCall(VecScatterEnd(scat_inact, Y, Y_inact, INSERT_VALUES, SCATTER_FORWARD));
455: /* Active set direction = 0 */
456: PetscCall(VecSet(Y_act, 0));
457: if (snes->jacobian != snes->jacobian_pre) PetscCall(MatCreateSubMatrix(snes->jacobian_pre, vi->IS_inact, vi->IS_inact, MAT_INITIAL_MATRIX, &prejac_inact_inact));
458: else prejac_inact_inact = jac_inact_inact;
460: PetscCall(ISEqual(vi->IS_inact_prev, vi->IS_inact, &isequal));
461: if (!isequal) {
462: PetscCall(SNESVIResetPCandKSP(snes, jac_inact_inact, prejac_inact_inact));
463: PetscCall(PCFieldSplitRestrictIS(pc, vi->IS_inact));
464: }
466: /* PetscCall(ISView(vi->IS_inact,0)); */
467: /* PetscCall(ISView(IS_act,0));*/
468: /* ierr = MatView(snes->jacobian_pre,0); */
470: PetscCall(KSPSetOperators(snes->ksp, jac_inact_inact, prejac_inact_inact));
471: PetscCall(KSPSetUp(snes->ksp));
472: {
473: PC pc;
474: PetscBool flg;
475: PetscCall(KSPGetPC(snes->ksp, &pc));
476: PetscCall(PetscObjectTypeCompare((PetscObject)pc, PCFIELDSPLIT, &flg));
477: if (flg) {
478: KSP *subksps;
479: PetscCall(PCFieldSplitGetSubKSP(pc, NULL, &subksps));
480: PetscCall(KSPGetPC(subksps[0], &pc));
481: PetscCall(PetscFree(subksps));
482: PetscCall(PetscObjectTypeCompare((PetscObject)pc, PCBJACOBI, &flg));
483: if (flg) {
484: PetscInt n, N = 101 * 101, j, cnts[3] = {0, 0, 0};
485: const PetscInt *ii;
487: PetscCall(ISGetSize(vi->IS_inact, &n));
488: PetscCall(ISGetIndices(vi->IS_inact, &ii));
489: for (j = 0; j < n; j++) {
490: if (ii[j] < N) cnts[0]++;
491: else if (ii[j] < 2 * N) cnts[1]++;
492: else if (ii[j] < 3 * N) cnts[2]++;
493: }
494: PetscCall(ISRestoreIndices(vi->IS_inact, &ii));
496: PetscCall(PCBJacobiSetTotalBlocks(pc, 3, cnts));
497: }
498: }
499: }
501: PetscCall(KSPSolve(snes->ksp, F_inact, Y_inact));
502: PetscCall(VecScatterBegin(scat_act, Y_act, Y, INSERT_VALUES, SCATTER_REVERSE));
503: PetscCall(VecScatterEnd(scat_act, Y_act, Y, INSERT_VALUES, SCATTER_REVERSE));
504: PetscCall(VecScatterBegin(scat_inact, Y_inact, Y, INSERT_VALUES, SCATTER_REVERSE));
505: PetscCall(VecScatterEnd(scat_inact, Y_inact, Y, INSERT_VALUES, SCATTER_REVERSE));
507: PetscCall(VecDestroy(&F_inact));
508: PetscCall(VecDestroy(&Y_act));
509: PetscCall(VecDestroy(&Y_inact));
510: PetscCall(VecScatterDestroy(&scat_act));
511: PetscCall(VecScatterDestroy(&scat_inact));
512: PetscCall(ISDestroy(&IS_act));
513: if (!isequal) {
514: PetscCall(ISDestroy(&vi->IS_inact_prev));
515: PetscCall(ISDuplicate(vi->IS_inact, &vi->IS_inact_prev));
516: }
517: PetscCall(ISDestroy(&vi->IS_inact));
518: PetscCall(MatDestroy(&jac_inact_inact));
519: if (snes->jacobian != snes->jacobian_pre) PetscCall(MatDestroy(&prejac_inact_inact));
521: PetscCall(KSPGetConvergedReason(snes->ksp, &kspreason));
522: if (kspreason < 0) {
523: if (++snes->numLinearSolveFailures >= snes->maxLinearSolveFailures) {
524: PetscCall(PetscInfo(snes, "iter=%" PetscInt_FMT ", number linear solve failures %" PetscInt_FMT " greater than current SNES allowed, stopping solve\n", snes->iter, snes->numLinearSolveFailures));
525: snes->reason = SNES_DIVERGED_LINEAR_SOLVE;
526: break;
527: }
528: }
530: PetscCall(KSPGetIterationNumber(snes->ksp, &lits));
531: snes->linear_its += lits;
532: PetscCall(PetscInfo(snes, "iter=%" PetscInt_FMT ", linear solve iterations=%" PetscInt_FMT "\n", snes->iter, lits));
533: /*
534: if (snes->ops->precheck) {
535: PetscBool changed_y = PETSC_FALSE;
536: PetscUseTypeMethod(snes,precheck ,X,Y,snes->precheck,&changed_y);
537: }
539: if (PetscLogPrintInfo) PetscCall(SNESVICheckResidual_Private(snes,snes->jacobian,F,Y,G,W));
540: */
541: /* Compute a (scaled) negative update in the line search routine:
542: Y <- X - lambda*Y
543: and evaluate G = function(Y) (depends on the line search).
544: */
545: PetscCall(VecCopy(Y, snes->vec_sol_update));
546: ynorm = 1;
547: gnorm = fnorm;
548: PetscCall(SNESLineSearchApply(snes->linesearch, X, F, &gnorm, Y));
549: PetscCall(DMDestroyVI(snes->dm));
550: if (snes->reason) break;
551: PetscCall(SNESLineSearchGetReason(snes->linesearch, &lsreason));
552: if (lsreason) {
553: if (snes->stol * xnorm > ynorm) {
554: snes->reason = SNES_CONVERGED_SNORM_RELATIVE;
555: break;
556: } else if (lsreason == SNES_LINESEARCH_FAILED_FUNCTION_DOMAIN) {
557: snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
558: break;
559: } else if (lsreason == SNES_LINESEARCH_FAILED_NANORINF) {
560: snes->reason = SNES_DIVERGED_FUNCTION_NANORINF;
561: break;
562: } else if (lsreason == SNES_LINESEARCH_FAILED_OBJECTIVE_DOMAIN) {
563: snes->reason = SNES_DIVERGED_OBJECTIVE_DOMAIN;
564: break;
565: } else if (lsreason == SNES_LINESEARCH_FAILED_JACOBIAN_DOMAIN) {
566: snes->reason = SNES_DIVERGED_JACOBIAN_DOMAIN;
567: break;
568: } else if (++snes->numFailures >= snes->maxFailures) {
569: PetscBool ismin;
571: snes->reason = SNES_DIVERGED_LINE_SEARCH;
572: PetscCall(SNESVICheckLocalMin_Private(snes, snes->jacobian, F, X, gnorm, &ismin));
573: if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN;
574: break;
575: }
576: }
577: PetscCall(SNESLineSearchGetNorms(snes->linesearch, &xnorm, &gnorm, &ynorm));
578: PetscCall(PetscInfo(snes, "fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n", (double)fnorm, (double)gnorm, (double)ynorm, (int)lsreason));
579: /* Update function and solution vectors */
580: fnorm = gnorm;
581: /* Monitor convergence */
582: PetscCall(PetscObjectSAWsTakeAccess((PetscObject)snes));
583: snes->iter = i + 1;
584: snes->norm = fnorm;
585: snes->xnorm = xnorm;
586: snes->ynorm = ynorm;
587: PetscCall(PetscObjectSAWsGrantAccess((PetscObject)snes));
588: PetscCall(SNESLogConvergenceHistory(snes, snes->norm, lits));
589: /* Test for convergence, xnorm = || X || */
590: if (snes->ops->converged != SNESConvergedSkip) PetscCall(VecNorm(X, NORM_2, &xnorm));
591: PetscCall(SNESConverged(snes, snes->iter, xnorm, ynorm, fnorm));
592: PetscCall(SNESMonitor(snes, snes->iter, snes->norm));
593: if (snes->reason) break;
594: }
595: /* 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 */
596: PetscCall(DMDestroyVI(snes->dm));
597: PetscFunctionReturn(PETSC_SUCCESS);
598: }
600: /*@C
601: SNESVISetRedundancyCheck - Provide a function to check for any redundancy in the VI active set
603: Logically Collective
605: Input Parameters:
606: + snes - the `SNESVINEWTONRSLS` context
607: . func - the function to check of redundancies
608: - ctx - optional context used by the function
610: Calling sequence of func:
611: + snes - the `SNES` context
612: . is_act - the set of points in the active sets
613: . is_redact - output, the set of points in the non-redundant active set
614: - ctx - optional context
616: Level: advanced
618: Note:
619: Sometimes the inactive set will result in a singular sub-Jacobian problem that needs to be solved, this allows the user,
620: when they know more about their specific problem to provide a function that removes the redundancy that results in the singular linear system
622: See `SNESVINEWTONRSLS` for a concise description of the active and inactive sets
624: .seealso: [](ch_snes), `SNES`, `SNESVINEWTONRSLS`, `SNESVIGetInactiveSet()`, `DMSetVI()`
625: @*/
626: PetscErrorCode SNESVISetRedundancyCheck(SNES snes, PetscErrorCode (*func)(SNES snes, IS is_act, IS *is_redact, PetscCtx ctx), PetscCtx ctx)
627: {
628: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
630: PetscFunctionBegin;
632: vi->checkredundancy = func;
633: vi->ctxP = ctx;
634: PetscFunctionReturn(PETSC_SUCCESS);
635: }
637: #if defined(PETSC_HAVE_MATLAB)
638: #include <engine.h>
639: #include <mex.h>
640: typedef struct {
641: char *funcname;
642: mxArray *ctx;
643: } SNESMatlabContext;
645: PetscErrorCode SNESVIRedundancyCheck_Matlab(SNES snes, IS is_act, IS *is_redact, PetscCtx ctx)
646: {
647: SNESMatlabContext *sctx = (SNESMatlabContext *)ctx;
648: int nlhs = 1, nrhs = 5;
649: mxArray *plhs[1], *prhs[5];
650: long long int l1 = 0, l2 = 0, ls = 0;
651: PetscInt *indices = NULL;
653: PetscFunctionBegin;
656: PetscAssertPointer(is_redact, 3);
657: PetscCheckSameComm(snes, 1, is_act, 2);
659: /* Create IS for reduced active set of size 0, its size and indices will
660: bet set by the MATLAB function */
661: PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)snes), 0, indices, PETSC_OWN_POINTER, is_redact));
662: /* call MATLAB function in ctx */
663: PetscCall(PetscArraycpy(&ls, &snes, 1));
664: PetscCall(PetscArraycpy(&l1, &is_act, 1));
665: PetscCall(PetscArraycpy(&l2, is_redact, 1));
666: prhs[0] = mxCreateDoubleScalar((double)ls);
667: prhs[1] = mxCreateDoubleScalar((double)l1);
668: prhs[2] = mxCreateDoubleScalar((double)l2);
669: prhs[3] = mxCreateString(sctx->funcname);
670: prhs[4] = sctx->ctx;
671: PetscCall(mexCallMATLAB(nlhs, plhs, nrhs, prhs, "PetscSNESVIRedundancyCheckInternal"));
672: PetscCall(mxGetScalar(plhs[0]));
673: mxDestroyArray(prhs[0]);
674: mxDestroyArray(prhs[1]);
675: mxDestroyArray(prhs[2]);
676: mxDestroyArray(prhs[3]);
677: mxDestroyArray(plhs[0]);
678: PetscFunctionReturn(PETSC_SUCCESS);
679: }
681: PetscErrorCode SNESVISetRedundancyCheckMatlab(SNES snes, const char *func, mxArray *ctx)
682: {
683: SNESMatlabContext *sctx;
685: PetscFunctionBegin;
686: /* currently sctx is memory bleed */
687: PetscCall(PetscNew(&sctx));
688: PetscCall(PetscStrallocpy(func, &sctx->funcname));
689: sctx->ctx = mxDuplicateArray(ctx);
690: PetscCall(SNESVISetRedundancyCheck(snes, SNESVIRedundancyCheck_Matlab, sctx));
691: PetscFunctionReturn(PETSC_SUCCESS);
692: }
694: #endif
696: static PetscErrorCode SNESSetUp_VINEWTONRSLS(SNES snes)
697: {
698: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
699: PetscInt *indices;
700: PetscInt i, n, rstart, rend;
701: SNESLineSearch linesearch;
703: PetscFunctionBegin;
704: PetscCall(SNESSetUp_VI(snes));
706: /* Set up previous active index set for the first snes solve
707: vi->IS_inact_prev = 0,1,2,....N */
709: PetscCall(VecGetOwnershipRange(snes->work[0], &rstart, &rend));
710: PetscCall(VecGetLocalSize(snes->work[0], &n));
711: PetscCall(PetscMalloc1(n, &indices));
712: for (i = 0; i < n; i++) indices[i] = rstart + i;
713: PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)snes), n, indices, PETSC_OWN_POINTER, &vi->IS_inact_prev));
715: /* set the line search functions */
716: if (!snes->linesearch) {
717: PetscCall(SNESGetLineSearch(snes, &linesearch));
718: PetscCall(SNESLineSearchSetType(linesearch, SNESLINESEARCHBT));
719: }
720: PetscFunctionReturn(PETSC_SUCCESS);
721: }
723: static PetscErrorCode SNESReset_VINEWTONRSLS(SNES snes)
724: {
725: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
727: PetscFunctionBegin;
728: PetscCall(SNESReset_VI(snes));
729: PetscCall(ISDestroy(&vi->IS_inact_prev));
730: PetscFunctionReturn(PETSC_SUCCESS);
731: }
733: /*MC
734: SNESVINEWTONRSLS - Reduced space active set solvers for variational inequalities based on Newton's method
736: Options Database Keys:
737: + -snes_type (vinewtonssls|vinewtonrsls) - A semi-smooth solver or a reduced space active set method
738: . -snes_vi_zero_tolerance - Tolerance for considering $u_i$ value to be on a bound.
739: . -snes_vi_monitor - Prints the number of active constraints (inactive set points) at each iteration.
740: . -snes_vi_monitor_residual - View the residual vector at each iteration, using zero for active constraints (i.e. the inactive variables).
741: - -snes_vi_monitor_active - View the active set by outputting a one for vector components in the active set and zero for the inactive.
743: Level: beginner
745: Note:
746: Reduced-space (active set methods) work as follows at each iteration\:
747: - 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
748: 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
749: the upper bound $u_i = U_i$ with also $[F(u)]_i \le 0.$
750: - 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
751: from both the rows and columns.
752: - A line search is then used to update the active variables (the inactive set of variables are not changed).
754: 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
755: 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.
757: See {cite}`benson2006flexible`
759: .seealso: [](ch_snes), `SNESVISetVariableBounds()`, `SNESVISetComputeVariableBounds()`, `SNESCreate()`, `SNES`, `SNESSetType()`, `SNESVINEWTONSSLS`, `SNESNEWTONTR`, `SNESLineSearchSetType()`, `SNESLineSearchSetPostCheck()`, `SNESLineSearchSetPreCheck()`, `SNESVIGetInactiveSet()`, `DMSetVI()`, `SNESVISetRedundancyCheck()`
760: M*/
761: PETSC_EXTERN PetscErrorCode SNESCreate_VINEWTONRSLS(SNES snes)
762: {
763: SNES_VINEWTONRSLS *vi;
764: SNESLineSearch linesearch;
766: PetscFunctionBegin;
767: snes->ops->reset = SNESReset_VINEWTONRSLS;
768: snes->ops->setup = SNESSetUp_VINEWTONRSLS;
769: snes->ops->solve = SNESSolve_VINEWTONRSLS;
770: snes->ops->destroy = SNESDestroy_VI;
771: snes->ops->setfromoptions = SNESSetFromOptions_VI;
772: snes->ops->view = NULL;
773: snes->ops->converged = SNESConvergedDefault_VI;
775: snes->usesksp = PETSC_TRUE;
776: snes->usesnpc = PETSC_FALSE;
778: PetscCall(SNESGetLineSearch(snes, &linesearch));
779: if (!((PetscObject)linesearch)->type_name) PetscCall(SNESLineSearchSetType(linesearch, SNESLINESEARCHBT));
780: PetscCall(SNESLineSearchBTSetAlpha(linesearch, 0.0));
782: snes->alwayscomputesfinalresidual = PETSC_TRUE;
784: PetscCall(SNESParametersInitialize(snes));
786: PetscCall(PetscNew(&vi));
787: snes->data = (void *)vi;
788: vi->checkredundancy = NULL;
790: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESVISetVariableBounds_C", SNESVISetVariableBounds_VI));
791: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESVISetComputeVariableBounds_C", SNESVISetComputeVariableBounds_VI));
792: PetscFunctionReturn(PETSC_SUCCESS);
793: }