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: .seealso: [](ch_snes), `SNES`, `SNESVINEWTONRSLS`
18: @*/
19: PetscErrorCode SNESVIGetInactiveSet(SNES snes, IS *inact)
20: {
21: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
23: PetscFunctionBegin;
24: *inact = vi->IS_inact;
25: PetscFunctionReturn(PETSC_SUCCESS);
26: }
28: /*
29: 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
30: defined by the reduced space method.
32: Simple calls the regular DM interpolation and restricts it to operation on the variables not associated with active constraints.
33: */
34: typedef struct {
35: PetscInt n; /* size of vectors in the reduced DM space */
36: IS inactive;
38: PetscErrorCode (*createinterpolation)(DM, DM, Mat *, Vec *); /* DM's original routines */
39: PetscErrorCode (*coarsen)(DM, MPI_Comm, DM *);
40: PetscErrorCode (*createglobalvector)(DM, Vec *);
41: PetscErrorCode (*createinjection)(DM, DM, Mat *);
42: PetscErrorCode (*hascreateinjection)(DM, PetscBool *);
44: DM dm; /* when destroying this object we need to reset the above function into the base DM */
45: } DM_SNESVI;
47: /*
48: DMCreateGlobalVector_SNESVI - Creates global vector of the size of the reduced space
49: */
50: static PetscErrorCode DMCreateGlobalVector_SNESVI(DM dm, Vec *vec)
51: {
52: PetscContainer isnes;
53: DM_SNESVI *dmsnesvi;
55: PetscFunctionBegin;
56: PetscCall(PetscObjectQuery((PetscObject)dm, "VI", (PetscObject *)&isnes));
57: PetscCheck(isnes, PetscObjectComm((PetscObject)dm), PETSC_ERR_PLIB, "Composed SNES is missing");
58: PetscCall(PetscContainerGetPointer(isnes, (void **)&dmsnesvi));
59: PetscCall(VecCreateMPI(PetscObjectComm((PetscObject)dm), dmsnesvi->n, PETSC_DETERMINE, vec));
60: PetscCall(VecSetDM(*vec, dm));
61: PetscFunctionReturn(PETSC_SUCCESS);
62: }
64: /*
65: DMCreateInterpolation_SNESVI - Modifieds the interpolation obtained from the DM by removing all rows and columns associated with active constraints.
66: */
67: static PetscErrorCode DMCreateInterpolation_SNESVI(DM dm1, DM dm2, Mat *mat, Vec *vec)
68: {
69: PetscContainer isnes;
70: DM_SNESVI *dmsnesvi1, *dmsnesvi2;
71: Mat interp;
73: PetscFunctionBegin;
74: PetscCall(PetscObjectQuery((PetscObject)dm1, "VI", (PetscObject *)&isnes));
75: PetscCheck(isnes, PetscObjectComm((PetscObject)dm1), PETSC_ERR_PLIB, "Composed VI data structure is missing");
76: PetscCall(PetscContainerGetPointer(isnes, (void **)&dmsnesvi1));
77: PetscCall(PetscObjectQuery((PetscObject)dm2, "VI", (PetscObject *)&isnes));
78: PetscCheck(isnes, PetscObjectComm((PetscObject)dm2), PETSC_ERR_PLIB, "Composed VI data structure is missing");
79: PetscCall(PetscContainerGetPointer(isnes, (void **)&dmsnesvi2));
81: PetscCall((*dmsnesvi1->createinterpolation)(dm1, dm2, &interp, NULL));
82: PetscCall(MatCreateSubMatrix(interp, dmsnesvi2->inactive, dmsnesvi1->inactive, MAT_INITIAL_MATRIX, mat));
83: PetscCall(MatDestroy(&interp));
84: *vec = NULL;
85: PetscFunctionReturn(PETSC_SUCCESS);
86: }
88: /*
89: DMCoarsen_SNESVI - Computes the regular coarsened DM then computes additional information about its inactive set
90: */
91: static PetscErrorCode DMCoarsen_SNESVI(DM dm1, MPI_Comm comm, DM *dm2)
92: {
93: PetscContainer isnes;
94: DM_SNESVI *dmsnesvi1;
95: Vec finemarked, coarsemarked;
96: IS inactive;
97: Mat inject;
98: const PetscInt *index;
99: PetscInt n, k, cnt = 0, rstart, *coarseindex;
100: PetscScalar *marked;
102: PetscFunctionBegin;
103: PetscCall(PetscObjectQuery((PetscObject)dm1, "VI", (PetscObject *)&isnes));
104: PetscCheck(isnes, PetscObjectComm((PetscObject)dm1), PETSC_ERR_PLIB, "Composed VI data structure is missing");
105: PetscCall(PetscContainerGetPointer(isnes, (void **)&dmsnesvi1));
107: /* get the original coarsen */
108: PetscCall((*dmsnesvi1->coarsen)(dm1, comm, dm2));
110: /* not sure why this extra reference is needed, but without the dm2 disappears too early */
111: /* Updating the KSPCreateVecs() to avoid using DMGetGlobalVector() when matrix is available removes the need for this reference? */
112: /* PetscCall(PetscObjectReference((PetscObject)*dm2));*/
114: /* need to set back global vectors in order to use the original injection */
115: PetscCall(DMClearGlobalVectors(dm1));
117: dm1->ops->createglobalvector = dmsnesvi1->createglobalvector;
119: PetscCall(DMCreateGlobalVector(dm1, &finemarked));
120: PetscCall(DMCreateGlobalVector(*dm2, &coarsemarked));
122: /*
123: fill finemarked with locations of inactive points
124: */
125: PetscCall(ISGetIndices(dmsnesvi1->inactive, &index));
126: PetscCall(ISGetLocalSize(dmsnesvi1->inactive, &n));
127: PetscCall(VecSet(finemarked, 0.0));
128: for (k = 0; k < n; k++) PetscCall(VecSetValue(finemarked, index[k], 1.0, INSERT_VALUES));
129: PetscCall(VecAssemblyBegin(finemarked));
130: PetscCall(VecAssemblyEnd(finemarked));
132: PetscCall(DMCreateInjection(*dm2, dm1, &inject));
133: PetscCall(MatRestrict(inject, finemarked, coarsemarked));
134: PetscCall(MatDestroy(&inject));
136: /*
137: create index set list of coarse inactive points from coarsemarked
138: */
139: PetscCall(VecGetLocalSize(coarsemarked, &n));
140: PetscCall(VecGetOwnershipRange(coarsemarked, &rstart, NULL));
141: PetscCall(VecGetArray(coarsemarked, &marked));
142: for (k = 0; k < n; k++) {
143: if (marked[k] != 0.0) cnt++;
144: }
145: PetscCall(PetscMalloc1(cnt, &coarseindex));
146: cnt = 0;
147: for (k = 0; k < n; k++) {
148: if (marked[k] != 0.0) coarseindex[cnt++] = k + rstart;
149: }
150: PetscCall(VecRestoreArray(coarsemarked, &marked));
151: PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)coarsemarked), cnt, coarseindex, PETSC_OWN_POINTER, &inactive));
153: PetscCall(DMClearGlobalVectors(dm1));
155: dm1->ops->createglobalvector = DMCreateGlobalVector_SNESVI;
157: PetscCall(DMSetVI(*dm2, inactive));
159: PetscCall(VecDestroy(&finemarked));
160: PetscCall(VecDestroy(&coarsemarked));
161: PetscCall(ISDestroy(&inactive));
162: PetscFunctionReturn(PETSC_SUCCESS);
163: }
165: static PetscErrorCode DMDestroy_SNESVI(void **ctx)
166: {
167: DM_SNESVI *dmsnesvi = (DM_SNESVI *)*ctx;
169: PetscFunctionBegin;
170: /* reset the base methods in the DM object that were changed when the DM_SNESVI was reset */
171: dmsnesvi->dm->ops->createinterpolation = dmsnesvi->createinterpolation;
172: dmsnesvi->dm->ops->coarsen = dmsnesvi->coarsen;
173: dmsnesvi->dm->ops->createglobalvector = dmsnesvi->createglobalvector;
174: dmsnesvi->dm->ops->createinjection = dmsnesvi->createinjection;
175: dmsnesvi->dm->ops->hascreateinjection = dmsnesvi->hascreateinjection;
176: /* need to clear out this vectors because some of them may not have a reference to the DM
177: but they are counted as having references to the DM in DMDestroy() */
178: PetscCall(DMClearGlobalVectors(dmsnesvi->dm));
180: PetscCall(ISDestroy(&dmsnesvi->inactive));
181: PetscCall(PetscFree(dmsnesvi));
182: PetscFunctionReturn(PETSC_SUCCESS);
183: }
185: /*@
186: DMSetVI - Marks a `DM` as associated with a VI problem. This causes the interpolation/restriction operators to
187: be restricted to only those variables NOT associated with active constraints.
189: Logically Collective
191: Input Parameters:
192: + dm - the `DM` object
193: - inactive - an `IS` indicating which points are currently not active
195: Level: intermediate
197: .seealso: [](ch_snes), `SNES`, `SNESVINEWTONRSLS`, `SNESVIGetInactiveSet()`
198: @*/
199: PetscErrorCode DMSetVI(DM dm, IS inactive)
200: {
201: PetscContainer isnes;
202: DM_SNESVI *dmsnesvi;
204: PetscFunctionBegin;
205: if (!dm) PetscFunctionReturn(PETSC_SUCCESS);
207: PetscCall(PetscObjectReference((PetscObject)inactive));
209: PetscCall(PetscObjectQuery((PetscObject)dm, "VI", (PetscObject *)&isnes));
210: if (!isnes) {
211: PetscCall(PetscNew(&dmsnesvi));
212: PetscCall(PetscObjectContainerCompose((PetscObject)dm, "VI", dmsnesvi, DMDestroy_SNESVI));
214: dmsnesvi->createinterpolation = dm->ops->createinterpolation;
215: dm->ops->createinterpolation = DMCreateInterpolation_SNESVI;
216: dmsnesvi->coarsen = dm->ops->coarsen;
217: dm->ops->coarsen = DMCoarsen_SNESVI;
218: dmsnesvi->createglobalvector = dm->ops->createglobalvector;
219: dm->ops->createglobalvector = DMCreateGlobalVector_SNESVI;
220: dmsnesvi->createinjection = dm->ops->createinjection;
221: dm->ops->createinjection = NULL;
222: dmsnesvi->hascreateinjection = dm->ops->hascreateinjection;
223: dm->ops->hascreateinjection = NULL;
224: } else {
225: PetscCall(PetscContainerGetPointer(isnes, (void **)&dmsnesvi));
226: PetscCall(ISDestroy(&dmsnesvi->inactive));
227: }
228: PetscCall(DMClearGlobalVectors(dm));
229: PetscCall(ISGetLocalSize(inactive, &dmsnesvi->n));
231: dmsnesvi->inactive = inactive;
232: dmsnesvi->dm = dm;
233: PetscFunctionReturn(PETSC_SUCCESS);
234: }
236: /*
237: DMDestroyVI - Frees the DM_SNESVI object contained in the DM
238: - also resets the function pointers in the DM for createinterpolation() etc to use the original DM
239: */
240: PetscErrorCode DMDestroyVI(DM dm)
241: {
242: PetscFunctionBegin;
243: if (!dm) PetscFunctionReturn(PETSC_SUCCESS);
244: PetscCall(PetscObjectCompose((PetscObject)dm, "VI", (PetscObject)NULL));
245: PetscFunctionReturn(PETSC_SUCCESS);
246: }
248: /* Create active and inactive set vectors. The local size of this vector is set and petsc computes the global size */
249: static PetscErrorCode SNESCreateSubVectors_VINEWTONRSLS(SNES snes, PetscInt n, Vec *newv)
250: {
251: Vec v;
253: PetscFunctionBegin;
254: PetscCall(VecCreate(PetscObjectComm((PetscObject)snes), &v));
255: PetscCall(VecSetSizes(v, n, PETSC_DECIDE));
256: PetscCall(VecSetType(v, VECSTANDARD));
257: *newv = v;
258: PetscFunctionReturn(PETSC_SUCCESS);
259: }
261: /* Resets the snes PC and KSP when the active set sizes change */
262: static PetscErrorCode SNESVIResetPCandKSP(SNES snes, Mat Amat, Mat Pmat)
263: {
264: KSP snesksp;
266: PetscFunctionBegin;
267: PetscCall(SNESGetKSP(snes, &snesksp));
268: PetscCall(KSPReset(snesksp));
269: PetscCall(KSPResetFromOptions(snesksp));
271: /*
272: KSP kspnew;
273: PC pcnew;
274: MatSolverType stype;
276: PetscCall(KSPCreate(PetscObjectComm((PetscObject)snes),&kspnew));
277: kspnew->pc_side = snesksp->pc_side;
278: kspnew->rtol = snesksp->rtol;
279: kspnew->abstol = snesksp->abstol;
280: kspnew->max_it = snesksp->max_it;
281: PetscCall(KSPSetType(kspnew,((PetscObject)snesksp)->type_name));
282: PetscCall(KSPGetPC(kspnew,&pcnew));
283: PetscCall(PCSetType(kspnew->pc,((PetscObject)snesksp->pc)->type_name));
284: PetscCall(PCSetOperators(kspnew->pc,Amat,Pmat));
285: PetscCall(PCFactorGetMatSolverType(snesksp->pc,&stype));
286: PetscCall(PCFactorSetMatSolverType(kspnew->pc,stype));
287: PetscCall(KSPDestroy(&snesksp));
288: snes->ksp = kspnew;
289: PetscCall(KSPSetFromOptions(kspnew));*/
290: PetscFunctionReturn(PETSC_SUCCESS);
291: }
293: /* Variational Inequality solver using reduce space method. No semismooth algorithm is
294: implemented in this algorithm. It basically identifies the active constraints and does
295: a linear solve on the other variables (those not associated with the active constraints). */
296: static PetscErrorCode SNESSolve_VINEWTONRSLS(SNES snes)
297: {
298: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
299: PetscInt maxits, i, lits;
300: SNESLineSearchReason lssucceed;
301: PetscReal fnorm, gnorm, xnorm = 0, ynorm;
302: Vec Y, X, F;
303: KSPConvergedReason kspreason;
304: KSP ksp;
305: PC pc;
307: PetscFunctionBegin;
308: /* Multigrid must use Galerkin for coarse grids with active set/reduced space methods; cannot rediscretize on coarser grids*/
309: PetscCall(SNESGetKSP(snes, &ksp));
310: PetscCall(KSPGetPC(ksp, &pc));
311: PetscCall(PCMGSetGalerkin(pc, PC_MG_GALERKIN_BOTH));
313: snes->numFailures = 0;
314: snes->numLinearSolveFailures = 0;
315: snes->reason = SNES_CONVERGED_ITERATING;
317: maxits = snes->max_its; /* maximum number of iterations */
318: X = snes->vec_sol; /* solution vector */
319: F = snes->vec_func; /* residual vector */
320: Y = snes->work[0]; /* work vectors */
322: PetscCall(SNESLineSearchSetVIFunctions(snes->linesearch, SNESVIProjectOntoBounds, SNESVIComputeInactiveSetFnorm));
323: PetscCall(SNESLineSearchSetVecs(snes->linesearch, X, NULL, NULL, NULL, NULL));
324: PetscCall(SNESLineSearchSetUp(snes->linesearch));
326: PetscCall(PetscObjectSAWsTakeAccess((PetscObject)snes));
327: snes->iter = 0;
328: snes->norm = 0.0;
329: PetscCall(PetscObjectSAWsGrantAccess((PetscObject)snes));
331: PetscCall(SNESVIProjectOntoBounds(snes, X));
332: PetscCall(SNESComputeFunction(snes, X, F));
333: PetscCall(SNESVIComputeInactiveSetFnorm(snes, F, X, &fnorm));
334: PetscCall(VecNorm(X, NORM_2, &xnorm)); /* xnorm <- ||x|| */
335: SNESCheckFunctionNorm(snes, fnorm);
336: PetscCall(PetscObjectSAWsTakeAccess((PetscObject)snes));
337: snes->norm = fnorm;
338: PetscCall(PetscObjectSAWsGrantAccess((PetscObject)snes));
339: PetscCall(SNESLogConvergenceHistory(snes, fnorm, 0));
341: /* test convergence */
342: PetscCall(SNESConverged(snes, 0, 0.0, 0.0, fnorm));
343: PetscCall(SNESMonitor(snes, 0, fnorm));
344: if (snes->reason) PetscFunctionReturn(PETSC_SUCCESS);
346: for (i = 0; i < maxits; i++) {
347: IS IS_act; /* _act -> active set _inact -> inactive set */
348: IS IS_redact; /* redundant active set */
349: VecScatter scat_act, scat_inact;
350: PetscInt nis_act, nis_inact;
351: Vec Y_act, Y_inact, F_inact;
352: Mat jac_inact_inact, prejac_inact_inact;
353: PetscBool isequal;
355: /* Call general purpose update function */
356: PetscTryTypeMethod(snes, update, snes->iter);
357: PetscCall(SNESComputeJacobian(snes, X, snes->jacobian, snes->jacobian_pre));
358: SNESCheckJacobianDomainerror(snes);
360: /* Create active and inactive index sets */
362: /*original
363: PetscCall(SNESVICreateIndexSets_RS(snes,X,F,&IS_act,&vi->IS_inact));
364: */
365: PetscCall(SNESVIGetActiveSetIS(snes, X, F, &IS_act));
367: if (vi->checkredundancy) {
368: PetscCall((*vi->checkredundancy)(snes, IS_act, &IS_redact, vi->ctxP));
369: if (IS_redact) {
370: PetscCall(ISSort(IS_redact));
371: PetscCall(ISComplement(IS_redact, X->map->rstart, X->map->rend, &vi->IS_inact));
372: PetscCall(ISDestroy(&IS_redact));
373: } else {
374: PetscCall(ISComplement(IS_act, X->map->rstart, X->map->rend, &vi->IS_inact));
375: }
376: } else {
377: PetscCall(ISComplement(IS_act, X->map->rstart, X->map->rend, &vi->IS_inact));
378: }
380: /* Create inactive set submatrix */
381: PetscCall(MatCreateSubMatrix(snes->jacobian, vi->IS_inact, vi->IS_inact, MAT_INITIAL_MATRIX, &jac_inact_inact));
383: if (0) { /* Dead code (temporary developer hack) */
384: IS keptrows;
385: PetscCall(MatFindNonzeroRows(jac_inact_inact, &keptrows));
386: if (keptrows) {
387: PetscInt cnt, *nrows, k;
388: const PetscInt *krows, *inact;
389: PetscInt rstart;
391: PetscCall(MatGetOwnershipRange(jac_inact_inact, &rstart, NULL));
392: PetscCall(MatDestroy(&jac_inact_inact));
393: PetscCall(ISDestroy(&IS_act));
395: PetscCall(ISGetLocalSize(keptrows, &cnt));
396: PetscCall(ISGetIndices(keptrows, &krows));
397: PetscCall(ISGetIndices(vi->IS_inact, &inact));
398: PetscCall(PetscMalloc1(cnt, &nrows));
399: for (k = 0; k < cnt; k++) nrows[k] = inact[krows[k] - rstart];
400: PetscCall(ISRestoreIndices(keptrows, &krows));
401: PetscCall(ISRestoreIndices(vi->IS_inact, &inact));
402: PetscCall(ISDestroy(&keptrows));
403: PetscCall(ISDestroy(&vi->IS_inact));
405: PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)snes), cnt, nrows, PETSC_OWN_POINTER, &vi->IS_inact));
406: PetscCall(ISComplement(vi->IS_inact, F->map->rstart, F->map->rend, &IS_act));
407: PetscCall(MatCreateSubMatrix(snes->jacobian, vi->IS_inact, vi->IS_inact, MAT_INITIAL_MATRIX, &jac_inact_inact));
408: }
409: }
410: PetscCall(DMSetVI(snes->dm, vi->IS_inact));
411: /* remove later */
413: /*
414: PetscCall(VecView(vi->xu,PETSC_VIEWER_BINARY_(((PetscObject)vi->xu)->comm)));
415: PetscCall(VecView(vi->xl,PETSC_VIEWER_BINARY_(((PetscObject)vi->xl)->comm)));
416: PetscCall(VecView(X,PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)X))));
417: PetscCall(VecView(F,PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)F))));
418: PetscCall(ISView(vi->IS_inact,PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)vi->IS_inact))));
419: */
421: /* Get sizes of active and inactive sets */
422: PetscCall(ISGetLocalSize(IS_act, &nis_act));
423: PetscCall(ISGetLocalSize(vi->IS_inact, &nis_inact));
425: /* Create active and inactive set vectors */
426: PetscCall(SNESCreateSubVectors_VINEWTONRSLS(snes, nis_inact, &F_inact));
427: PetscCall(SNESCreateSubVectors_VINEWTONRSLS(snes, nis_act, &Y_act));
428: PetscCall(SNESCreateSubVectors_VINEWTONRSLS(snes, nis_inact, &Y_inact));
430: /* Create scatter contexts */
431: PetscCall(VecScatterCreate(Y, IS_act, Y_act, NULL, &scat_act));
432: PetscCall(VecScatterCreate(Y, vi->IS_inact, Y_inact, NULL, &scat_inact));
434: /* Do a vec scatter to active and inactive set vectors */
435: PetscCall(VecScatterBegin(scat_inact, F, F_inact, INSERT_VALUES, SCATTER_FORWARD));
436: PetscCall(VecScatterEnd(scat_inact, F, F_inact, INSERT_VALUES, SCATTER_FORWARD));
438: PetscCall(VecScatterBegin(scat_act, Y, Y_act, INSERT_VALUES, SCATTER_FORWARD));
439: PetscCall(VecScatterEnd(scat_act, Y, Y_act, INSERT_VALUES, SCATTER_FORWARD));
441: PetscCall(VecScatterBegin(scat_inact, Y, Y_inact, INSERT_VALUES, SCATTER_FORWARD));
442: PetscCall(VecScatterEnd(scat_inact, Y, Y_inact, INSERT_VALUES, SCATTER_FORWARD));
444: /* Active set direction = 0 */
445: PetscCall(VecSet(Y_act, 0));
446: if (snes->jacobian != snes->jacobian_pre) {
447: PetscCall(MatCreateSubMatrix(snes->jacobian_pre, vi->IS_inact, vi->IS_inact, MAT_INITIAL_MATRIX, &prejac_inact_inact));
448: } else prejac_inact_inact = jac_inact_inact;
450: PetscCall(ISEqual(vi->IS_inact_prev, vi->IS_inact, &isequal));
451: if (!isequal) {
452: PetscCall(SNESVIResetPCandKSP(snes, jac_inact_inact, prejac_inact_inact));
453: PetscCall(PCFieldSplitRestrictIS(pc, vi->IS_inact));
454: }
456: /* PetscCall(ISView(vi->IS_inact,0)); */
457: /* PetscCall(ISView(IS_act,0));*/
458: /* ierr = MatView(snes->jacobian_pre,0); */
460: PetscCall(KSPSetOperators(snes->ksp, jac_inact_inact, prejac_inact_inact));
461: PetscCall(KSPSetUp(snes->ksp));
462: {
463: PC pc;
464: PetscBool flg;
465: PetscCall(KSPGetPC(snes->ksp, &pc));
466: PetscCall(PetscObjectTypeCompare((PetscObject)pc, PCFIELDSPLIT, &flg));
467: if (flg) {
468: KSP *subksps;
469: PetscCall(PCFieldSplitGetSubKSP(pc, NULL, &subksps));
470: PetscCall(KSPGetPC(subksps[0], &pc));
471: PetscCall(PetscFree(subksps));
472: PetscCall(PetscObjectTypeCompare((PetscObject)pc, PCBJACOBI, &flg));
473: if (flg) {
474: PetscInt n, N = 101 * 101, j, cnts[3] = {0, 0, 0};
475: const PetscInt *ii;
477: PetscCall(ISGetSize(vi->IS_inact, &n));
478: PetscCall(ISGetIndices(vi->IS_inact, &ii));
479: for (j = 0; j < n; j++) {
480: if (ii[j] < N) cnts[0]++;
481: else if (ii[j] < 2 * N) cnts[1]++;
482: else if (ii[j] < 3 * N) cnts[2]++;
483: }
484: PetscCall(ISRestoreIndices(vi->IS_inact, &ii));
486: PetscCall(PCBJacobiSetTotalBlocks(pc, 3, cnts));
487: }
488: }
489: }
491: PetscCall(KSPSolve(snes->ksp, F_inact, Y_inact));
492: PetscCall(VecScatterBegin(scat_act, Y_act, Y, INSERT_VALUES, SCATTER_REVERSE));
493: PetscCall(VecScatterEnd(scat_act, Y_act, Y, INSERT_VALUES, SCATTER_REVERSE));
494: PetscCall(VecScatterBegin(scat_inact, Y_inact, Y, INSERT_VALUES, SCATTER_REVERSE));
495: PetscCall(VecScatterEnd(scat_inact, Y_inact, Y, INSERT_VALUES, SCATTER_REVERSE));
497: PetscCall(VecDestroy(&F_inact));
498: PetscCall(VecDestroy(&Y_act));
499: PetscCall(VecDestroy(&Y_inact));
500: PetscCall(VecScatterDestroy(&scat_act));
501: PetscCall(VecScatterDestroy(&scat_inact));
502: PetscCall(ISDestroy(&IS_act));
503: if (!isequal) {
504: PetscCall(ISDestroy(&vi->IS_inact_prev));
505: PetscCall(ISDuplicate(vi->IS_inact, &vi->IS_inact_prev));
506: }
507: PetscCall(ISDestroy(&vi->IS_inact));
508: PetscCall(MatDestroy(&jac_inact_inact));
509: if (snes->jacobian != snes->jacobian_pre) PetscCall(MatDestroy(&prejac_inact_inact));
511: PetscCall(KSPGetConvergedReason(snes->ksp, &kspreason));
512: if (kspreason < 0) {
513: if (++snes->numLinearSolveFailures >= snes->maxLinearSolveFailures) {
514: PetscCall(PetscInfo(snes, "iter=%" PetscInt_FMT ", number linear solve failures %" PetscInt_FMT " greater than current SNES allowed, stopping solve\n", snes->iter, snes->numLinearSolveFailures));
515: snes->reason = SNES_DIVERGED_LINEAR_SOLVE;
516: break;
517: }
518: }
520: PetscCall(KSPGetIterationNumber(snes->ksp, &lits));
521: snes->linear_its += lits;
522: PetscCall(PetscInfo(snes, "iter=%" PetscInt_FMT ", linear solve iterations=%" PetscInt_FMT "\n", snes->iter, lits));
523: /*
524: if (snes->ops->precheck) {
525: PetscBool changed_y = PETSC_FALSE;
526: PetscUseTypeMethod(snes,precheck ,X,Y,snes->precheck,&changed_y);
527: }
529: if (PetscLogPrintInfo) PetscCall(SNESVICheckResidual_Private(snes,snes->jacobian,F,Y,G,W));
530: */
531: /* Compute a (scaled) negative update in the line search routine:
532: Y <- X - lambda*Y
533: and evaluate G = function(Y) (depends on the line search).
534: */
535: PetscCall(VecCopy(Y, snes->vec_sol_update));
536: ynorm = 1;
537: gnorm = fnorm;
538: PetscCall(SNESLineSearchApply(snes->linesearch, X, F, &gnorm, Y));
539: PetscCall(SNESLineSearchGetReason(snes->linesearch, &lssucceed));
540: PetscCall(SNESLineSearchGetNorms(snes->linesearch, &xnorm, &gnorm, &ynorm));
541: PetscCall(PetscInfo(snes, "fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n", (double)fnorm, (double)gnorm, (double)ynorm, (int)lssucceed));
542: if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break;
543: if (snes->domainerror) {
544: snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
545: PetscCall(DMDestroyVI(snes->dm));
546: PetscFunctionReturn(PETSC_SUCCESS);
547: }
548: if (lssucceed) {
549: if (++snes->numFailures >= snes->maxFailures) {
550: PetscBool ismin;
551: snes->reason = SNES_DIVERGED_LINE_SEARCH;
552: PetscCall(SNESVICheckLocalMin_Private(snes, snes->jacobian, F, X, gnorm, &ismin));
553: if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN;
554: break;
555: }
556: }
557: PetscCall(DMDestroyVI(snes->dm));
558: /* Update function and solution vectors */
559: fnorm = gnorm;
560: /* Monitor convergence */
561: PetscCall(PetscObjectSAWsTakeAccess((PetscObject)snes));
562: snes->iter = i + 1;
563: snes->norm = fnorm;
564: snes->xnorm = xnorm;
565: snes->ynorm = ynorm;
566: PetscCall(PetscObjectSAWsGrantAccess((PetscObject)snes));
567: PetscCall(SNESLogConvergenceHistory(snes, snes->norm, lits));
568: /* Test for convergence, xnorm = || X || */
569: if (snes->ops->converged != SNESConvergedSkip) PetscCall(VecNorm(X, NORM_2, &xnorm));
570: PetscCall(SNESConverged(snes, snes->iter, xnorm, ynorm, fnorm));
571: PetscCall(SNESMonitor(snes, snes->iter, snes->norm));
572: if (snes->reason) break;
573: }
574: /* 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 */
575: PetscCall(DMDestroyVI(snes->dm));
576: PetscFunctionReturn(PETSC_SUCCESS);
577: }
579: /*@C
580: SNESVISetRedundancyCheck - Provide a function to check for any redundancy in the VI active set
582: Logically Collective
584: Input Parameters:
585: + snes - the `SNESVINEWTONRSLS` context
586: . func - the function to check of redundancies
587: - ctx - optional context used by the function
589: Level: advanced
591: Note:
592: Sometimes the inactive set will result in a singular sub-Jacobian problem that needs to be solved, this allows the user,
593: when they know more about their specific problem to provide a function that removes the redundancy that results in the singular linear system
595: .seealso: [](ch_snes), `SNES`, `SNESVINEWTONRSLS`, `SNESVIGetInactiveSet()`, `DMSetVI()`
596: @*/
597: PetscErrorCode SNESVISetRedundancyCheck(SNES snes, PetscErrorCode (*func)(SNES, IS, IS *, void *), void *ctx)
598: {
599: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
601: PetscFunctionBegin;
603: vi->checkredundancy = func;
604: vi->ctxP = ctx;
605: PetscFunctionReturn(PETSC_SUCCESS);
606: }
608: #if defined(PETSC_HAVE_MATLAB)
609: #include <engine.h>
610: #include <mex.h>
611: typedef struct {
612: char *funcname;
613: mxArray *ctx;
614: } SNESMatlabContext;
616: PetscErrorCode SNESVIRedundancyCheck_Matlab(SNES snes, IS is_act, IS *is_redact, void *ctx)
617: {
618: SNESMatlabContext *sctx = (SNESMatlabContext *)ctx;
619: int nlhs = 1, nrhs = 5;
620: mxArray *plhs[1], *prhs[5];
621: long long int l1 = 0, l2 = 0, ls = 0;
622: PetscInt *indices = NULL;
624: PetscFunctionBegin;
627: PetscAssertPointer(is_redact, 3);
628: PetscCheckSameComm(snes, 1, is_act, 2);
630: /* Create IS for reduced active set of size 0, its size and indices will
631: bet set by the MATLAB function */
632: PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)snes), 0, indices, PETSC_OWN_POINTER, is_redact));
633: /* call MATLAB function in ctx */
634: PetscCall(PetscArraycpy(&ls, &snes, 1));
635: PetscCall(PetscArraycpy(&l1, &is_act, 1));
636: PetscCall(PetscArraycpy(&l2, is_redact, 1));
637: prhs[0] = mxCreateDoubleScalar((double)ls);
638: prhs[1] = mxCreateDoubleScalar((double)l1);
639: prhs[2] = mxCreateDoubleScalar((double)l2);
640: prhs[3] = mxCreateString(sctx->funcname);
641: prhs[4] = sctx->ctx;
642: PetscCall(mexCallMATLAB(nlhs, plhs, nrhs, prhs, "PetscSNESVIRedundancyCheckInternal"));
643: PetscCall(mxGetScalar(plhs[0]));
644: mxDestroyArray(prhs[0]);
645: mxDestroyArray(prhs[1]);
646: mxDestroyArray(prhs[2]);
647: mxDestroyArray(prhs[3]);
648: mxDestroyArray(plhs[0]);
649: PetscFunctionReturn(PETSC_SUCCESS);
650: }
652: PetscErrorCode SNESVISetRedundancyCheckMatlab(SNES snes, const char *func, mxArray *ctx)
653: {
654: SNESMatlabContext *sctx;
656: PetscFunctionBegin;
657: /* currently sctx is memory bleed */
658: PetscCall(PetscNew(&sctx));
659: PetscCall(PetscStrallocpy(func, &sctx->funcname));
660: sctx->ctx = mxDuplicateArray(ctx);
661: PetscCall(SNESVISetRedundancyCheck(snes, SNESVIRedundancyCheck_Matlab, sctx));
662: PetscFunctionReturn(PETSC_SUCCESS);
663: }
665: #endif
667: static PetscErrorCode SNESSetUp_VINEWTONRSLS(SNES snes)
668: {
669: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
670: PetscInt *indices;
671: PetscInt i, n, rstart, rend;
672: SNESLineSearch linesearch;
674: PetscFunctionBegin;
675: PetscCall(SNESSetUp_VI(snes));
677: /* Set up previous active index set for the first snes solve
678: vi->IS_inact_prev = 0,1,2,....N */
680: PetscCall(VecGetOwnershipRange(snes->vec_sol, &rstart, &rend));
681: PetscCall(VecGetLocalSize(snes->vec_sol, &n));
682: PetscCall(PetscMalloc1(n, &indices));
683: for (i = 0; i < n; i++) indices[i] = rstart + i;
684: PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)snes), n, indices, PETSC_OWN_POINTER, &vi->IS_inact_prev));
686: /* set the line search functions */
687: if (!snes->linesearch) {
688: PetscCall(SNESGetLineSearch(snes, &linesearch));
689: PetscCall(SNESLineSearchSetType(linesearch, SNESLINESEARCHBT));
690: }
691: PetscFunctionReturn(PETSC_SUCCESS);
692: }
694: static PetscErrorCode SNESReset_VINEWTONRSLS(SNES snes)
695: {
696: SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS *)snes->data;
698: PetscFunctionBegin;
699: PetscCall(SNESReset_VI(snes));
700: PetscCall(ISDestroy(&vi->IS_inact_prev));
701: PetscFunctionReturn(PETSC_SUCCESS);
702: }
704: /*MC
705: SNESVINEWTONRSLS - Reduced space active set solvers for variational inequalities based on Newton's method
707: Options Database Keys:
708: + -snes_type <vinewtonssls,vinewtonrsls> - a semi-smooth solver or a reduced space active set method
709: - -snes_vi_monitor - prints the number of active constraints at each iteration.
711: Level: beginner
713: Note:
714: At each set of this methods the algorithm produces an inactive set of variables that are constrained to their current values
715: (because changing these values would result in those variables no longer satisfying the inequality constraints)
716: and produces a step direction by solving the linear system arising from the Jacobian with the inactive variables removed. In other
717: words on a reduced space of the solution space. Based on the Newton update it then adjusts the inactive set for the next iteration.
719: See {cite}`benson2006flexible`
721: .seealso: [](ch_snes), `SNESVISetVariableBounds()`, `SNESVISetComputeVariableBounds()`, `SNESCreate()`, `SNES`, `SNESSetType()`, `SNESVINEWTONSSLS`, `SNESNEWTONTR`, `SNESLineSearchSetType()`, `SNESLineSearchSetPostCheck()`, `SNESLineSearchSetPreCheck()`, `SNESVIGetInactiveSet()`, `DMSetVI()`, `SNESVISetRedundancyCheck()`
722: M*/
723: PETSC_EXTERN PetscErrorCode SNESCreate_VINEWTONRSLS(SNES snes)
724: {
725: SNES_VINEWTONRSLS *vi;
726: SNESLineSearch linesearch;
728: PetscFunctionBegin;
729: snes->ops->reset = SNESReset_VINEWTONRSLS;
730: snes->ops->setup = SNESSetUp_VINEWTONRSLS;
731: snes->ops->solve = SNESSolve_VINEWTONRSLS;
732: snes->ops->destroy = SNESDestroy_VI;
733: snes->ops->setfromoptions = SNESSetFromOptions_VI;
734: snes->ops->view = NULL;
735: snes->ops->converged = SNESConvergedDefault_VI;
737: snes->usesksp = PETSC_TRUE;
738: snes->usesnpc = PETSC_FALSE;
740: PetscCall(SNESGetLineSearch(snes, &linesearch));
741: if (!((PetscObject)linesearch)->type_name) PetscCall(SNESLineSearchSetType(linesearch, SNESLINESEARCHBT));
742: PetscCall(SNESLineSearchBTSetAlpha(linesearch, 0.0));
744: snes->alwayscomputesfinalresidual = PETSC_TRUE;
746: PetscCall(SNESParametersInitialize(snes));
748: PetscCall(PetscNew(&vi));
749: snes->data = (void *)vi;
750: vi->checkredundancy = NULL;
752: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESVISetVariableBounds_C", SNESVISetVariableBounds_VI));
753: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESVISetComputeVariableBounds_C", SNESVISetComputeVariableBounds_VI));
754: PetscFunctionReturn(PETSC_SUCCESS);
755: }