Actual source code: nasm.c
1: #include <petsc/private/snesimpl.h>
2: #include <petscdm.h>
4: typedef struct {
5: PetscInt n; /* local subdomains */
6: SNES *subsnes; /* nonlinear solvers for each subdomain */
7: Vec *x; /* solution vectors */
8: Vec *xl; /* solution local vectors */
9: Vec *y; /* step vectors */
10: Vec *b; /* rhs vectors */
11: Vec weight; /* weighting for adding updates on overlaps, in global space */
12: VecScatter *oscatter; /* scatter from global space to the subdomain global space */
13: VecScatter *oscatter_copy; /* copy of the above */
14: VecScatter *iscatter; /* scatter from global space to the nonoverlapping subdomain space */
15: VecScatter *gscatter; /* scatter from global space to the subdomain local space */
16: PCASMType type; /* ASM type */
17: PetscBool usesdm; /* use the DM for setting up the subproblems */
18: PetscBool finaljacobian; /* compute the jacobian of the converged solution */
19: PetscReal damping; /* damping parameter for updates from the blocks */
20: PetscBool weight_set; /* use a weight in the overlap updates */
22: /* logging events */
23: PetscLogEvent eventrestrictinterp;
24: PetscLogEvent eventsubsolve;
26: PetscInt fjtype; /* type of computed jacobian */
27: Vec xinit; /* initial solution in case the final jacobian type is computed as first */
28: } SNES_NASM;
30: const char *const SNESNASMTypes[] = {"NONE", "RESTRICT", "INTERPOLATE", "BASIC", "PCASMType", "PC_ASM_", NULL};
31: const char *const SNESNASMFJTypes[] = {"FINALOUTER", "FINALINNER", "INITIAL"};
33: static PetscErrorCode SNESReset_NASM(SNES snes)
34: {
35: SNES_NASM *nasm = (SNES_NASM *)snes->data;
36: PetscInt i;
38: PetscFunctionBegin;
39: for (i = 0; i < nasm->n; i++) {
40: if (nasm->xl) PetscCall(VecDestroy(&nasm->xl[i]));
41: if (nasm->x) PetscCall(VecDestroy(&nasm->x[i]));
42: if (nasm->y) PetscCall(VecDestroy(&nasm->y[i]));
43: if (nasm->b) PetscCall(VecDestroy(&nasm->b[i]));
45: if (nasm->subsnes) PetscCall(SNESDestroy(&nasm->subsnes[i]));
46: if (nasm->oscatter) PetscCall(VecScatterDestroy(&nasm->oscatter[i]));
47: if (nasm->oscatter_copy) PetscCall(VecScatterDestroy(&nasm->oscatter_copy[i]));
48: if (nasm->iscatter) PetscCall(VecScatterDestroy(&nasm->iscatter[i]));
49: if (nasm->gscatter) PetscCall(VecScatterDestroy(&nasm->gscatter[i]));
50: }
52: PetscCall(PetscFree(nasm->x));
53: PetscCall(PetscFree(nasm->xl));
54: PetscCall(PetscFree(nasm->y));
55: PetscCall(PetscFree(nasm->b));
57: if (nasm->xinit) PetscCall(VecDestroy(&nasm->xinit));
59: PetscCall(PetscFree(nasm->subsnes));
60: PetscCall(PetscFree(nasm->oscatter));
61: PetscCall(PetscFree(nasm->oscatter_copy));
62: PetscCall(PetscFree(nasm->iscatter));
63: PetscCall(PetscFree(nasm->gscatter));
65: if (nasm->weight_set) PetscCall(VecDestroy(&nasm->weight));
67: nasm->eventrestrictinterp = 0;
68: nasm->eventsubsolve = 0;
69: PetscFunctionReturn(PETSC_SUCCESS);
70: }
72: static PetscErrorCode SNESDestroy_NASM(SNES snes)
73: {
74: PetscFunctionBegin;
75: PetscCall(SNESReset_NASM(snes));
76: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESNASMSetType_C", NULL));
77: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESNASMGetType_C", NULL));
78: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESNASMSetSubdomains_C", NULL));
79: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESNASMGetSubdomains_C", NULL));
80: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESNASMSetDamping_C", NULL));
81: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESNASMGetDamping_C", NULL));
82: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESNASMGetSubdomainVecs_C", NULL));
83: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESNASMSetComputeFinalJacobian_C", NULL));
84: PetscCall(PetscFree(snes->data));
85: PetscFunctionReturn(PETSC_SUCCESS);
86: }
88: static PetscErrorCode DMGlobalToLocalSubDomainDirichletHook_Private(DM dm, Vec g, InsertMode mode, Vec l, void *ctx)
89: {
90: Vec bcs = (Vec)ctx;
92: PetscFunctionBegin;
93: PetscCall(VecCopy(bcs, l));
94: PetscFunctionReturn(PETSC_SUCCESS);
95: }
97: static PetscErrorCode SNESSetUp_NASM(SNES snes)
98: {
99: SNES_NASM *nasm = (SNES_NASM *)snes->data;
100: DM dm, subdm;
101: DM *subdms;
102: PetscInt i;
103: const char *optionsprefix;
104: Vec F;
106: PetscFunctionBegin;
107: if (!nasm->subsnes) {
108: PetscCall(SNESGetDM(snes, &dm));
109: if (dm) {
110: nasm->usesdm = PETSC_TRUE;
111: PetscCall(DMCreateDomainDecomposition(dm, &nasm->n, NULL, NULL, NULL, &subdms));
112: PetscCheck(subdms, PetscObjectComm((PetscObject)dm), PETSC_ERR_ARG_WRONGSTATE, "DM has no default decomposition defined. Set subsolves manually with SNESNASMSetSubdomains().");
113: PetscCall(DMCreateDomainDecompositionScatters(dm, nasm->n, subdms, &nasm->iscatter, &nasm->oscatter, &nasm->gscatter));
114: PetscCall(PetscMalloc1(nasm->n, &nasm->oscatter_copy));
115: for (i = 0; i < nasm->n; i++) PetscCall(VecScatterCopy(nasm->oscatter[i], &nasm->oscatter_copy[i]));
117: PetscCall(SNESGetOptionsPrefix(snes, &optionsprefix));
118: PetscCall(PetscMalloc1(nasm->n, &nasm->subsnes));
119: for (i = 0; i < nasm->n; i++) {
120: PetscCall(SNESCreate(PetscObjectComm((PetscObject)subdms[i]), &nasm->subsnes[i]));
121: PetscCall(PetscObjectIncrementTabLevel((PetscObject)nasm->subsnes[i], (PetscObject)snes, 1));
122: PetscCall(SNESAppendOptionsPrefix(nasm->subsnes[i], optionsprefix));
123: PetscCall(SNESAppendOptionsPrefix(nasm->subsnes[i], "sub_"));
124: PetscCall(SNESSetDM(nasm->subsnes[i], subdms[i]));
125: if (snes->ops->usercompute) {
126: PetscCall(SNESSetComputeApplicationContext(nasm->subsnes[i], snes->ops->usercompute, snes->ops->userdestroy));
127: } else {
128: void *ctx;
130: PetscCall(SNESGetApplicationContext(snes, &ctx));
131: PetscCall(SNESSetApplicationContext(nasm->subsnes[i], ctx));
132: }
133: PetscCall(SNESSetFromOptions(nasm->subsnes[i]));
134: PetscCall(DMDestroy(&subdms[i]));
135: }
136: PetscCall(PetscFree(subdms));
137: } else SETERRQ(PetscObjectComm((PetscObject)snes), PETSC_ERR_ARG_WRONGSTATE, "Cannot construct local problems automatically without a DM!");
138: } else SETERRQ(PetscObjectComm((PetscObject)snes), PETSC_ERR_ARG_WRONGSTATE, "Must set subproblems manually if there is no DM!");
139: /* allocate the global vectors */
140: if (!nasm->x) PetscCall(PetscCalloc1(nasm->n, &nasm->x));
141: if (!nasm->xl) PetscCall(PetscCalloc1(nasm->n, &nasm->xl));
142: if (!nasm->y) PetscCall(PetscCalloc1(nasm->n, &nasm->y));
143: if (!nasm->b) PetscCall(PetscCalloc1(nasm->n, &nasm->b));
145: for (i = 0; i < nasm->n; i++) {
146: PetscCall(SNESGetFunction(nasm->subsnes[i], &F, NULL, NULL));
147: if (!nasm->x[i]) PetscCall(VecDuplicate(F, &nasm->x[i]));
148: if (!nasm->y[i]) PetscCall(VecDuplicate(F, &nasm->y[i]));
149: if (!nasm->b[i]) PetscCall(VecDuplicate(F, &nasm->b[i]));
150: if (!nasm->xl[i]) {
151: PetscCall(SNESGetDM(nasm->subsnes[i], &subdm));
152: PetscCall(DMCreateLocalVector(subdm, &nasm->xl[i]));
153: PetscCall(DMGlobalToLocalHookAdd(subdm, DMGlobalToLocalSubDomainDirichletHook_Private, NULL, nasm->xl[i]));
154: }
155: }
156: if (nasm->finaljacobian) {
157: PetscCall(SNESSetUpMatrices(snes));
158: if (nasm->fjtype == 2) PetscCall(VecDuplicate(snes->vec_sol, &nasm->xinit));
159: for (i = 0; i < nasm->n; i++) PetscCall(SNESSetUpMatrices(nasm->subsnes[i]));
160: }
161: PetscFunctionReturn(PETSC_SUCCESS);
162: }
164: static PetscErrorCode SNESSetFromOptions_NASM(SNES snes, PetscOptionItems *PetscOptionsObject)
165: {
166: PCASMType asmtype;
167: PetscBool flg, monflg;
168: SNES_NASM *nasm = (SNES_NASM *)snes->data;
170: PetscFunctionBegin;
171: PetscOptionsHeadBegin(PetscOptionsObject, "Nonlinear Additive Schwarz options");
172: PetscCall(PetscOptionsEnum("-snes_nasm_type", "Type of restriction/extension", "", SNESNASMTypes, (PetscEnum)nasm->type, (PetscEnum *)&asmtype, &flg));
173: if (flg) PetscCall(SNESNASMSetType(snes, asmtype));
174: flg = PETSC_FALSE;
175: monflg = PETSC_TRUE;
176: PetscCall(PetscOptionsReal("-snes_nasm_damping", "The new solution is obtained as old solution plus dmp times (sum of the solutions on the subdomains)", "SNESNASMSetDamping", nasm->damping, &nasm->damping, &flg));
177: if (flg) PetscCall(SNESNASMSetDamping(snes, nasm->damping));
178: PetscCall(PetscOptionsDeprecated("-snes_nasm_sub_view", NULL, "3.15", "Use -snes_view ::ascii_info_detail"));
179: PetscCall(PetscOptionsBool("-snes_nasm_finaljacobian", "Compute the global jacobian of the final iterate (for ASPIN)", "", nasm->finaljacobian, &nasm->finaljacobian, NULL));
180: PetscCall(PetscOptionsEList("-snes_nasm_finaljacobian_type", "The type of the final jacobian computed.", "", SNESNASMFJTypes, 3, SNESNASMFJTypes[0], &nasm->fjtype, NULL));
181: PetscCall(PetscOptionsBool("-snes_nasm_log", "Log times for subSNES solves and restriction", "", monflg, &monflg, &flg));
182: if (flg) {
183: PetscCall(PetscLogEventRegister("SNESNASMSubSolve", ((PetscObject)snes)->classid, &nasm->eventsubsolve));
184: PetscCall(PetscLogEventRegister("SNESNASMRestrict", ((PetscObject)snes)->classid, &nasm->eventrestrictinterp));
185: }
186: PetscOptionsHeadEnd();
187: PetscFunctionReturn(PETSC_SUCCESS);
188: }
190: static PetscErrorCode SNESView_NASM(SNES snes, PetscViewer viewer)
191: {
192: SNES_NASM *nasm = (SNES_NASM *)snes->data;
193: PetscMPIInt rank, size;
194: PetscInt i, N, bsz;
195: PetscBool iascii, isstring;
196: PetscViewer sviewer;
197: MPI_Comm comm;
198: PetscViewerFormat format;
199: const char *prefix;
201: PetscFunctionBegin;
202: PetscCall(PetscObjectGetComm((PetscObject)snes, &comm));
203: PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
204: PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERSTRING, &isstring));
205: PetscCallMPI(MPI_Comm_rank(comm, &rank));
206: PetscCallMPI(MPI_Comm_size(comm, &size));
207: PetscCallMPI(MPIU_Allreduce(&nasm->n, &N, 1, MPIU_INT, MPI_SUM, comm));
208: if (iascii) {
209: PetscCall(PetscViewerASCIIPrintf(viewer, " total subdomain blocks = %" PetscInt_FMT "\n", N));
210: PetscCall(PetscViewerGetFormat(viewer, &format));
211: if (format != PETSC_VIEWER_ASCII_INFO_DETAIL) {
212: if (nasm->subsnes) {
213: PetscCall(PetscViewerASCIIPrintf(viewer, " Local solver information for first block on rank 0:\n"));
214: PetscCall(SNESGetOptionsPrefix(snes, &prefix));
215: PetscCall(PetscViewerASCIIPrintf(viewer, " Use -%ssnes_view ::ascii_info_detail to display information for all blocks\n", prefix ? prefix : ""));
216: PetscCall(PetscViewerASCIIPushTab(viewer));
217: PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
218: if (rank == 0) {
219: PetscCall(PetscViewerASCIIPushTab(sviewer));
220: PetscCall(SNESView(nasm->subsnes[0], sviewer));
221: PetscCall(PetscViewerASCIIPopTab(sviewer));
222: }
223: PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
224: PetscCall(PetscViewerASCIIPopTab(viewer));
225: }
226: } else {
227: /* print the solver on each block */
228: PetscCall(PetscViewerASCIIPushSynchronized(viewer));
229: PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, " [%d] number of local blocks = %" PetscInt_FMT "\n", (int)rank, nasm->n));
230: PetscCall(PetscViewerFlush(viewer));
231: PetscCall(PetscViewerASCIIPopSynchronized(viewer));
232: PetscCall(PetscViewerASCIIPrintf(viewer, " Local solver information for each block is in the following SNES objects:\n"));
233: PetscCall(PetscViewerASCIIPushTab(viewer));
234: PetscCall(PetscViewerASCIIPrintf(viewer, "- - - - - - - - - - - - - - - - - -\n"));
235: PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
236: for (i = 0; i < nasm->n; i++) {
237: PetscCall(VecGetLocalSize(nasm->x[i], &bsz));
238: PetscCall(PetscViewerASCIIPrintf(sviewer, "[%d] local block number %" PetscInt_FMT ", size = %" PetscInt_FMT "\n", (int)rank, i, bsz));
239: PetscCall(SNESView(nasm->subsnes[i], sviewer));
240: PetscCall(PetscViewerASCIIPrintf(sviewer, "- - - - - - - - - - - - - - - - - -\n"));
241: }
242: PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
243: PetscCall(PetscViewerASCIIPopTab(viewer));
244: }
245: } else if (isstring) {
246: PetscCall(PetscViewerStringSPrintf(viewer, " blocks=%" PetscInt_FMT ",type=%s", N, SNESNASMTypes[nasm->type]));
247: PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
248: if (nasm->subsnes && rank == 0) PetscCall(SNESView(nasm->subsnes[0], sviewer));
249: PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
250: }
251: PetscFunctionReturn(PETSC_SUCCESS);
252: }
254: /*@
255: SNESNASMSetType - Set the type of subdomain update used for the nonlinear additive Schwarz solver `SNESNASM`
257: Logically Collective
259: Input Parameters:
260: + snes - the `SNES` context
261: - type - the type of update, `PC_ASM_BASIC` or `PC_ASM_RESTRICT`
263: Options Database Key:
264: . -snes_nasm_type <basic,restrict> - type of subdomain update used
266: Level: intermediate
268: .seealso: [](ch_snes), `SNES`, `SNESNASM`, `SNESNASMGetType()`, `PCASMSetType()`, `PC_ASM_BASIC`, `PC_ASM_RESTRICT`, `PCASMType`
269: @*/
270: PetscErrorCode SNESNASMSetType(SNES snes, PCASMType type)
271: {
272: PetscErrorCode (*f)(SNES, PCASMType);
274: PetscFunctionBegin;
275: PetscCall(PetscObjectQueryFunction((PetscObject)snes, "SNESNASMSetType_C", &f));
276: if (f) PetscCall((f)(snes, type));
277: PetscFunctionReturn(PETSC_SUCCESS);
278: }
280: static PetscErrorCode SNESNASMSetType_NASM(SNES snes, PCASMType type)
281: {
282: SNES_NASM *nasm = (SNES_NASM *)snes->data;
284: PetscFunctionBegin;
285: PetscCheck(type == PC_ASM_BASIC || type == PC_ASM_RESTRICT, PetscObjectComm((PetscObject)snes), PETSC_ERR_ARG_OUTOFRANGE, "SNESNASM only supports basic and restrict types");
286: nasm->type = type;
287: PetscFunctionReturn(PETSC_SUCCESS);
288: }
290: /*@
291: SNESNASMGetType - Get the type of subdomain update used for the nonlinear additive Schwarz solver `SNESNASM`
293: Logically Collective
295: Input Parameter:
296: . snes - the `SNES` context
298: Output Parameter:
299: . type - the type of update
301: Level: intermediate
303: .seealso: [](ch_snes), `SNES`, `SNESNASM`, `SNESNASMSetType()`, `PCASMGetType()`, `PC_ASM_BASIC`, `PC_ASM_RESTRICT`, `PCASMType`
304: @*/
305: PetscErrorCode SNESNASMGetType(SNES snes, PCASMType *type)
306: {
307: PetscFunctionBegin;
308: PetscUseMethod(snes, "SNESNASMGetType_C", (SNES, PCASMType *), (snes, type));
309: PetscFunctionReturn(PETSC_SUCCESS);
310: }
312: static PetscErrorCode SNESNASMGetType_NASM(SNES snes, PCASMType *type)
313: {
314: SNES_NASM *nasm = (SNES_NASM *)snes->data;
316: PetscFunctionBegin;
317: *type = nasm->type;
318: PetscFunctionReturn(PETSC_SUCCESS);
319: }
321: /*@
322: SNESNASMSetSubdomains - Manually Set the context required to restrict and solve subdomain problems in the nonlinear additive Schwarz solver
324: Logically Collective
326: Input Parameters:
327: + snes - the `SNES` context
328: . n - the number of local subdomains
329: . subsnes - solvers defined on the local subdomains
330: . iscatter - scatters into the nonoverlapping portions of the local subdomains
331: . oscatter - scatters into the overlapping portions of the local subdomains
332: - gscatter - scatters into the (ghosted) local vector of the local subdomain
334: Level: intermediate
336: .seealso: [](ch_snes), `SNES`, `SNESNASM`, `SNESNASMGetSubdomains()`
337: @*/
338: PetscErrorCode SNESNASMSetSubdomains(SNES snes, PetscInt n, SNES subsnes[], VecScatter iscatter[], VecScatter oscatter[], VecScatter gscatter[])
339: {
340: PetscErrorCode (*f)(SNES, PetscInt, SNES *, VecScatter *, VecScatter *, VecScatter *);
342: PetscFunctionBegin;
343: PetscCall(PetscObjectQueryFunction((PetscObject)snes, "SNESNASMSetSubdomains_C", &f));
344: if (f) PetscCall((f)(snes, n, subsnes, iscatter, oscatter, gscatter));
345: PetscFunctionReturn(PETSC_SUCCESS);
346: }
348: static PetscErrorCode SNESNASMSetSubdomains_NASM(SNES snes, PetscInt n, SNES subsnes[], VecScatter iscatter[], VecScatter oscatter[], VecScatter gscatter[])
349: {
350: PetscInt i;
351: SNES_NASM *nasm = (SNES_NASM *)snes->data;
353: PetscFunctionBegin;
354: PetscCheck(!snes->setupcalled, PetscObjectComm((PetscObject)snes), PETSC_ERR_ARG_WRONGSTATE, "SNESNASMSetSubdomains() should be called before calling SNESSetUp().");
356: /* tear down the previously set things */
357: PetscCall(SNESReset(snes));
359: nasm->n = n;
360: if (oscatter) {
361: for (i = 0; i < n; i++) PetscCall(PetscObjectReference((PetscObject)oscatter[i]));
362: }
363: if (iscatter) {
364: for (i = 0; i < n; i++) PetscCall(PetscObjectReference((PetscObject)iscatter[i]));
365: }
366: if (gscatter) {
367: for (i = 0; i < n; i++) PetscCall(PetscObjectReference((PetscObject)gscatter[i]));
368: }
369: if (oscatter) {
370: PetscCall(PetscMalloc1(n, &nasm->oscatter));
371: PetscCall(PetscMalloc1(n, &nasm->oscatter_copy));
372: for (i = 0; i < n; i++) {
373: nasm->oscatter[i] = oscatter[i];
374: PetscCall(VecScatterCopy(oscatter[i], &nasm->oscatter_copy[i]));
375: }
376: }
377: if (iscatter) {
378: PetscCall(PetscMalloc1(n, &nasm->iscatter));
379: for (i = 0; i < n; i++) nasm->iscatter[i] = iscatter[i];
380: }
381: if (gscatter) {
382: PetscCall(PetscMalloc1(n, &nasm->gscatter));
383: for (i = 0; i < n; i++) nasm->gscatter[i] = gscatter[i];
384: }
386: if (subsnes) {
387: PetscCall(PetscMalloc1(n, &nasm->subsnes));
388: for (i = 0; i < n; i++) nasm->subsnes[i] = subsnes[i];
389: }
390: PetscFunctionReturn(PETSC_SUCCESS);
391: }
393: /*@
394: SNESNASMGetSubdomains - Get the local subdomain contexts for the nonlinear additive Schwarz solver
396: Not Collective but some of the objects returned will be parallel
398: Input Parameter:
399: . snes - the `SNES` context
401: Output Parameters:
402: + n - the number of local subdomains
403: . subsnes - solvers defined on the local subdomains
404: . iscatter - scatters into the nonoverlapping portions of the local subdomains
405: . oscatter - scatters into the overlapping portions of the local subdomains
406: - gscatter - scatters into the (ghosted) local vector of the local subdomain
408: Level: intermediate
410: .seealso: [](ch_snes), `SNES`, `SNESNASM`, `SNESNASMSetSubdomains()`
411: @*/
412: PetscErrorCode SNESNASMGetSubdomains(SNES snes, PetscInt *n, SNES *subsnes[], VecScatter *iscatter[], VecScatter *oscatter[], VecScatter *gscatter[])
413: {
414: PetscErrorCode (*f)(SNES, PetscInt *, SNES **, VecScatter **, VecScatter **, VecScatter **);
416: PetscFunctionBegin;
417: PetscCall(PetscObjectQueryFunction((PetscObject)snes, "SNESNASMGetSubdomains_C", &f));
418: if (f) PetscCall((f)(snes, n, subsnes, iscatter, oscatter, gscatter));
419: PetscFunctionReturn(PETSC_SUCCESS);
420: }
422: static PetscErrorCode SNESNASMGetSubdomains_NASM(SNES snes, PetscInt *n, SNES *subsnes[], VecScatter *iscatter[], VecScatter *oscatter[], VecScatter *gscatter[])
423: {
424: SNES_NASM *nasm = (SNES_NASM *)snes->data;
426: PetscFunctionBegin;
427: if (n) *n = nasm->n;
428: if (oscatter) *oscatter = nasm->oscatter;
429: if (iscatter) *iscatter = nasm->iscatter;
430: if (gscatter) *gscatter = nasm->gscatter;
431: if (subsnes) *subsnes = nasm->subsnes;
432: PetscFunctionReturn(PETSC_SUCCESS);
433: }
435: /*@
436: SNESNASMGetSubdomainVecs - Get the processor-local subdomain vectors for the nonlinear additive Schwarz solver
438: Not Collective
440: Input Parameter:
441: . snes - the `SNES` context
443: Output Parameters:
444: + n - the number of local subdomains
445: . x - The subdomain solution vector
446: . y - The subdomain step vector
447: . b - The subdomain RHS vector
448: - xl - The subdomain local vectors (ghosted)
450: Level: developer
452: .seealso: [](ch_snes), `SNES`, `SNESNASM`, `SNESNASMGetSubdomains()`
453: @*/
454: PetscErrorCode SNESNASMGetSubdomainVecs(SNES snes, PetscInt *n, Vec **x, Vec **y, Vec **b, Vec **xl)
455: {
456: PetscErrorCode (*f)(SNES, PetscInt *, Vec **, Vec **, Vec **, Vec **);
458: PetscFunctionBegin;
459: PetscCall(PetscObjectQueryFunction((PetscObject)snes, "SNESNASMGetSubdomainVecs_C", &f));
460: if (f) PetscCall((f)(snes, n, x, y, b, xl));
461: PetscFunctionReturn(PETSC_SUCCESS);
462: }
464: static PetscErrorCode SNESNASMGetSubdomainVecs_NASM(SNES snes, PetscInt *n, Vec **x, Vec **y, Vec **b, Vec **xl)
465: {
466: SNES_NASM *nasm = (SNES_NASM *)snes->data;
468: PetscFunctionBegin;
469: if (n) *n = nasm->n;
470: if (x) *x = nasm->x;
471: if (y) *y = nasm->y;
472: if (b) *b = nasm->b;
473: if (xl) *xl = nasm->xl;
474: PetscFunctionReturn(PETSC_SUCCESS);
475: }
477: /*@
478: SNESNASMSetComputeFinalJacobian - Schedules the computation of the global and subdomain Jacobians upon convergence for the
479: nonlinear additive Schwarz solver
481: Collective
483: Input Parameters:
484: + snes - the SNES context
485: - flg - `PETSC_TRUE` to compute the Jacobians
487: Level: developer
489: Notes:
490: This is used almost exclusively in the implementation of `SNESASPIN`, where the converged subdomain and global Jacobian
491: is needed at each linear iteration.
493: .seealso: [](ch_snes), `SNES`, `SNESNASM`, `SNESNASMGetSubdomains()`
494: @*/
495: PetscErrorCode SNESNASMSetComputeFinalJacobian(SNES snes, PetscBool flg)
496: {
497: PetscErrorCode (*f)(SNES, PetscBool);
499: PetscFunctionBegin;
500: PetscCall(PetscObjectQueryFunction((PetscObject)snes, "SNESNASMSetComputeFinalJacobian_C", &f));
501: if (f) PetscCall((f)(snes, flg));
502: PetscFunctionReturn(PETSC_SUCCESS);
503: }
505: static PetscErrorCode SNESNASMSetComputeFinalJacobian_NASM(SNES snes, PetscBool flg)
506: {
507: SNES_NASM *nasm = (SNES_NASM *)snes->data;
509: PetscFunctionBegin;
510: nasm->finaljacobian = flg;
511: PetscFunctionReturn(PETSC_SUCCESS);
512: }
514: /*@
515: SNESNASMSetDamping - Sets the update damping for `SNESNASM` the nonlinear additive Schwarz solver
517: Logically Collective
519: Input Parameters:
520: + snes - the `SNES` context
521: - dmp - damping
523: Options Database Key:
524: . -snes_nasm_damping <dmp> - the new solution is obtained as old solution plus `dmp` times (sum of the solutions on the subdomains)
526: Level: intermediate
528: Note:
529: The new solution is obtained as old solution plus dmp times (sum of the solutions on the subdomains)
531: .seealso: [](ch_snes), `SNES`, `SNESNASM`, `SNESNASMGetDamping()`
532: @*/
533: PetscErrorCode SNESNASMSetDamping(SNES snes, PetscReal dmp)
534: {
535: PetscErrorCode (*f)(SNES, PetscReal);
537: PetscFunctionBegin;
538: PetscCall(PetscObjectQueryFunction((PetscObject)snes, "SNESNASMSetDamping_C", (void (**)(void))&f));
539: if (f) PetscCall((f)(snes, dmp));
540: PetscFunctionReturn(PETSC_SUCCESS);
541: }
543: static PetscErrorCode SNESNASMSetDamping_NASM(SNES snes, PetscReal dmp)
544: {
545: SNES_NASM *nasm = (SNES_NASM *)snes->data;
547: PetscFunctionBegin;
548: nasm->damping = dmp;
549: PetscFunctionReturn(PETSC_SUCCESS);
550: }
552: /*@
553: SNESNASMGetDamping - Gets the update damping for `SNESNASM` the nonlinear additive Schwarz solver
555: Not Collective
557: Input Parameter:
558: . snes - the `SNES` context
560: Output Parameter:
561: . dmp - damping
563: Level: intermediate
565: .seealso: [](ch_snes), `SNES`, `SNESNASM`, `SNESNASMSetDamping()`
566: @*/
567: PetscErrorCode SNESNASMGetDamping(SNES snes, PetscReal *dmp)
568: {
569: PetscFunctionBegin;
570: PetscUseMethod(snes, "SNESNASMGetDamping_C", (SNES, PetscReal *), (snes, dmp));
571: PetscFunctionReturn(PETSC_SUCCESS);
572: }
574: static PetscErrorCode SNESNASMGetDamping_NASM(SNES snes, PetscReal *dmp)
575: {
576: SNES_NASM *nasm = (SNES_NASM *)snes->data;
578: PetscFunctionBegin;
579: *dmp = nasm->damping;
580: PetscFunctionReturn(PETSC_SUCCESS);
581: }
583: /*
584: Input Parameters:
585: + snes - The solver
586: . B - The RHS vector
587: - X - The initial guess
589: Output Parameter:
590: . Y - The solution update
592: TODO: All scatters should be packed into one
593: */
594: static PetscErrorCode SNESNASMSolveLocal_Private(SNES snes, Vec B, Vec Y, Vec X)
595: {
596: SNES_NASM *nasm = (SNES_NASM *)snes->data;
597: SNES subsnes;
598: PetscInt i;
599: PetscReal dmp;
600: Vec Xl, Bl, Yl, Xlloc;
601: VecScatter iscat, oscat, gscat, oscat_copy;
602: DM dm, subdm;
603: PCASMType type;
605: PetscFunctionBegin;
606: PetscCall(SNESNASMGetType(snes, &type));
607: PetscCall(SNESGetDM(snes, &dm));
608: PetscCall(VecSet(Y, 0));
609: if (nasm->eventrestrictinterp) PetscCall(PetscLogEventBegin(nasm->eventrestrictinterp, snes, 0, 0, 0));
610: for (i = 0; i < nasm->n; i++) { /* scatter the global solution to the overlap solution and the local solution */
611: Xl = nasm->x[i];
612: Xlloc = nasm->xl[i];
613: oscat = nasm->oscatter[i];
614: oscat_copy = nasm->oscatter_copy[i];
615: gscat = nasm->gscatter[i];
616: PetscCall(VecScatterBegin(oscat, X, Xl, INSERT_VALUES, SCATTER_FORWARD));
617: PetscCall(VecScatterBegin(gscat, X, Xlloc, INSERT_VALUES, SCATTER_FORWARD));
619: if (B) {
620: /* scatter the RHS to the local RHS */
621: Bl = nasm->b[i];
622: PetscCall(VecScatterBegin(oscat_copy, B, Bl, INSERT_VALUES, SCATTER_FORWARD));
623: }
624: }
625: if (nasm->eventrestrictinterp) PetscCall(PetscLogEventEnd(nasm->eventrestrictinterp, snes, 0, 0, 0));
627: if (nasm->eventsubsolve) PetscCall(PetscLogEventBegin(nasm->eventsubsolve, snes, 0, 0, 0));
628: for (i = 0; i < nasm->n; i++) {
629: PetscErrorCode (*bl)(DM, Vec, void *);
630: void *bctx;
632: Xl = nasm->x[i];
633: Xlloc = nasm->xl[i];
634: Yl = nasm->y[i];
635: subsnes = nasm->subsnes[i];
636: PetscCall(SNESGetDM(subsnes, &subdm));
637: iscat = nasm->iscatter[i];
638: oscat = nasm->oscatter[i];
639: oscat_copy = nasm->oscatter_copy[i];
640: gscat = nasm->gscatter[i];
641: PetscCall(VecScatterEnd(oscat, X, Xl, INSERT_VALUES, SCATTER_FORWARD));
642: PetscCall(VecScatterEnd(gscat, X, Xlloc, INSERT_VALUES, SCATTER_FORWARD));
643: if (B) {
644: Bl = nasm->b[i];
645: PetscCall(VecScatterEnd(oscat_copy, B, Bl, INSERT_VALUES, SCATTER_FORWARD));
646: } else Bl = NULL;
648: PetscCall(SNESGetDM(subsnes, &subdm));
649: PetscCall(DMSNESGetBoundaryLocal(subdm, &bl, &bctx));
650: if (bl) PetscCall((*bl)(subdm, Xlloc, bctx));
652: PetscCall(DMSubDomainRestrict(dm, oscat, gscat, subdm));
653: PetscCall(VecCopy(Xl, Yl));
654: PetscCall(SNESSolve(subsnes, Bl, Xl));
655: PetscCall(VecAYPX(Yl, -1.0, Xl));
656: PetscCall(VecScale(Yl, nasm->damping));
657: if (type == PC_ASM_BASIC) {
658: PetscCall(VecScatterBegin(oscat, Yl, Y, ADD_VALUES, SCATTER_REVERSE));
659: PetscCall(VecScatterEnd(oscat, Yl, Y, ADD_VALUES, SCATTER_REVERSE));
660: } else if (type == PC_ASM_RESTRICT) {
661: PetscCall(VecScatterBegin(iscat, Yl, Y, ADD_VALUES, SCATTER_REVERSE));
662: PetscCall(VecScatterEnd(iscat, Yl, Y, ADD_VALUES, SCATTER_REVERSE));
663: } else SETERRQ(PetscObjectComm((PetscObject)snes), PETSC_ERR_ARG_WRONGSTATE, "Only basic and restrict types are supported for SNESNASM");
664: }
665: if (nasm->eventsubsolve) PetscCall(PetscLogEventEnd(nasm->eventsubsolve, snes, 0, 0, 0));
666: if (nasm->eventrestrictinterp) PetscCall(PetscLogEventBegin(nasm->eventrestrictinterp, snes, 0, 0, 0));
667: if (nasm->weight_set) PetscCall(VecPointwiseMult(Y, Y, nasm->weight));
668: if (nasm->eventrestrictinterp) PetscCall(PetscLogEventEnd(nasm->eventrestrictinterp, snes, 0, 0, 0));
669: PetscCall(SNESNASMGetDamping(snes, &dmp));
670: PetscCall(VecAXPY(X, dmp, Y));
671: PetscFunctionReturn(PETSC_SUCCESS);
672: }
674: static PetscErrorCode SNESNASMComputeFinalJacobian_Private(SNES snes, Vec Xfinal)
675: {
676: Vec X = Xfinal;
677: SNES_NASM *nasm = (SNES_NASM *)snes->data;
678: SNES subsnes;
679: PetscInt i, lag = 1;
680: Vec Xlloc, Xl, Fl, F;
681: VecScatter oscat, gscat;
682: DM dm, subdm;
684: PetscFunctionBegin;
685: if (nasm->fjtype == 2) X = nasm->xinit;
686: F = snes->vec_func;
687: if (snes->normschedule == SNES_NORM_NONE) PetscCall(SNESComputeFunction(snes, X, F));
688: PetscCall(SNESComputeJacobian(snes, X, snes->jacobian, snes->jacobian_pre));
689: PetscCall(SNESGetDM(snes, &dm));
690: if (nasm->eventrestrictinterp) PetscCall(PetscLogEventBegin(nasm->eventrestrictinterp, snes, 0, 0, 0));
691: if (nasm->fjtype != 1) {
692: for (i = 0; i < nasm->n; i++) {
693: Xlloc = nasm->xl[i];
694: gscat = nasm->gscatter[i];
695: PetscCall(VecScatterBegin(gscat, X, Xlloc, INSERT_VALUES, SCATTER_FORWARD));
696: }
697: }
698: if (nasm->eventrestrictinterp) PetscCall(PetscLogEventEnd(nasm->eventrestrictinterp, snes, 0, 0, 0));
699: for (i = 0; i < nasm->n; i++) {
700: Fl = nasm->subsnes[i]->vec_func;
701: Xl = nasm->x[i];
702: Xlloc = nasm->xl[i];
703: subsnes = nasm->subsnes[i];
704: oscat = nasm->oscatter[i];
705: gscat = nasm->gscatter[i];
706: if (nasm->fjtype != 1) PetscCall(VecScatterEnd(gscat, X, Xlloc, INSERT_VALUES, SCATTER_FORWARD));
707: PetscCall(SNESGetDM(subsnes, &subdm));
708: PetscCall(DMSubDomainRestrict(dm, oscat, gscat, subdm));
709: if (nasm->fjtype != 1) {
710: PetscCall(DMLocalToGlobalBegin(subdm, Xlloc, INSERT_VALUES, Xl));
711: PetscCall(DMLocalToGlobalEnd(subdm, Xlloc, INSERT_VALUES, Xl));
712: }
713: if (subsnes->lagjacobian == -1) subsnes->lagjacobian = -2;
714: else if (subsnes->lagjacobian > 1) lag = subsnes->lagjacobian;
715: PetscCall(SNESComputeFunction(subsnes, Xl, Fl));
716: PetscCall(SNESComputeJacobian(subsnes, Xl, subsnes->jacobian, subsnes->jacobian_pre));
717: if (lag > 1) subsnes->lagjacobian = lag;
718: }
719: PetscFunctionReturn(PETSC_SUCCESS);
720: }
722: static PetscErrorCode SNESSolve_NASM(SNES snes)
723: {
724: Vec F;
725: Vec X;
726: Vec B;
727: Vec Y;
728: PetscInt i;
729: PetscReal fnorm = 0.0;
730: SNESNormSchedule normschedule;
731: SNES_NASM *nasm = (SNES_NASM *)snes->data;
733: PetscFunctionBegin;
734: PetscCheck(!snes->xl & !snes->xu && !snes->ops->computevariablebounds, PetscObjectComm((PetscObject)snes), PETSC_ERR_ARG_WRONGSTATE, "SNES solver %s does not support bounds", ((PetscObject)snes)->type_name);
736: PetscCall(PetscCitationsRegister(SNESCitation, &SNEScite));
737: X = snes->vec_sol;
738: Y = snes->vec_sol_update;
739: F = snes->vec_func;
740: B = snes->vec_rhs;
742: PetscCall(PetscObjectSAWsTakeAccess((PetscObject)snes));
743: snes->iter = 0;
744: snes->norm = 0.;
745: PetscCall(PetscObjectSAWsGrantAccess((PetscObject)snes));
746: snes->reason = SNES_CONVERGED_ITERATING;
747: PetscCall(SNESGetNormSchedule(snes, &normschedule));
748: if (normschedule == SNES_NORM_ALWAYS || normschedule == SNES_NORM_INITIAL_ONLY || normschedule == SNES_NORM_INITIAL_FINAL_ONLY || !snes->max_its) {
749: /* compute the initial function and preconditioned update delX */
750: if (!snes->vec_func_init_set) {
751: PetscCall(SNESComputeFunction(snes, X, F));
752: } else snes->vec_func_init_set = PETSC_FALSE;
754: PetscCall(VecNorm(F, NORM_2, &fnorm)); /* fnorm <- ||F|| */
755: SNESCheckFunctionNorm(snes, fnorm);
756: PetscCall(PetscObjectSAWsTakeAccess((PetscObject)snes));
757: snes->iter = 0;
758: snes->norm = fnorm;
759: PetscCall(PetscObjectSAWsGrantAccess((PetscObject)snes));
760: PetscCall(SNESLogConvergenceHistory(snes, snes->norm, 0));
762: /* test convergence */
763: PetscCall(SNESConverged(snes, 0, 0.0, 0.0, fnorm));
764: PetscCall(SNESMonitor(snes, 0, snes->norm));
765: if (snes->reason) PetscFunctionReturn(PETSC_SUCCESS);
766: } else {
767: PetscCall(PetscObjectSAWsGrantAccess((PetscObject)snes));
768: PetscCall(SNESLogConvergenceHistory(snes, snes->norm, 0));
769: PetscCall(SNESMonitor(snes, snes->iter, snes->norm));
770: }
772: /* Call general purpose update function */
773: PetscTryTypeMethod(snes, update, snes->iter);
774: /* copy the initial solution over for later */
775: if (nasm->fjtype == 2) PetscCall(VecCopy(X, nasm->xinit));
777: for (i = 0; i < snes->max_its; i++) {
778: PetscCall(SNESNASMSolveLocal_Private(snes, B, Y, X));
779: if (normschedule == SNES_NORM_ALWAYS || ((i == snes->max_its - 1) && (normschedule == SNES_NORM_INITIAL_FINAL_ONLY || normschedule == SNES_NORM_FINAL_ONLY))) {
780: PetscCall(SNESComputeFunction(snes, X, F));
781: PetscCall(VecNorm(F, NORM_2, &fnorm)); /* fnorm <- ||F|| */
782: SNESCheckFunctionNorm(snes, fnorm);
783: }
784: /* Monitor convergence */
785: PetscCall(PetscObjectSAWsTakeAccess((PetscObject)snes));
786: snes->iter = i + 1;
787: snes->norm = fnorm;
788: PetscCall(PetscObjectSAWsGrantAccess((PetscObject)snes));
789: PetscCall(SNESLogConvergenceHistory(snes, snes->norm, 0));
790: /* Test for convergence */
791: PetscCall(SNESConverged(snes, snes->iter, 0.0, 0.0, fnorm));
792: PetscCall(SNESMonitor(snes, snes->iter, snes->norm));
793: if (snes->reason) break;
794: /* Call general purpose update function */
795: PetscTryTypeMethod(snes, update, snes->iter);
796: }
797: if (nasm->finaljacobian) {
798: PetscCall(SNESNASMComputeFinalJacobian_Private(snes, X));
799: SNESCheckJacobianDomainerror(snes);
800: }
801: PetscFunctionReturn(PETSC_SUCCESS);
802: }
804: /*MC
805: SNESNASM - Nonlinear Additive Schwarz solver {cite}`ck02`, {cite}`bruneknepleysmithtu15`
807: Options Database Keys:
808: + -snes_nasm_log - enable logging events for the communication and solve stages
809: . -snes_nasm_type <basic,restrict> - type of subdomain update used
810: . -snes_nasm_damping <dmp> - the new solution is obtained as old solution plus dmp times (sum of the solutions on the subdomains)
811: . -snes_nasm_finaljacobian - compute the local and global Jacobians of the final iterate
812: . -snes_nasm_finaljacobian_type <finalinner,finalouter,initial> - pick state the Jacobian is calculated at
813: . -sub_snes_ - options prefix of the subdomain nonlinear solves
814: . -sub_ksp_ - options prefix of the subdomain Krylov solver
815: - -sub_pc_ - options prefix of the subdomain preconditioner
817: Level: advanced
819: Note:
820: This is not often used directly as a solver, it converges too slowly. However it works well as a nonlinear preconditioner for
821: the `SNESASPIN` solver
823: Developer Note:
824: This is a non-Newton based nonlinear solver that does not directly require a Jacobian; hence the flag snes->usesksp is set to
825: false and `SNESView()` and -snes_view do not display a `KSP` object. However, if the flag nasm->finaljacobian is set (for example, if
826: `SNESNASM` is used as a nonlinear preconditioner for `SNESASPIN`) then `SNESSetUpMatrices()` is called to generate the
827: Jacobian (needed by `SNESASPIN`)
828: and this utilizes the inner `KSP` object for storing the matrices, but the `KSP` is never used for solving a linear system. When `SNESNASM` is
829: used by `SNESASPIN` they share the same Jacobian matrices because `SNESSetUp()` (called on the outer `SNESASPIN`) causes the inner `SNES`
830: object (in this case `SNESNASM`) to inherit the outer Jacobian matrices.
832: .seealso: [](ch_snes), `SNESCreate()`, `SNES`, `SNESSetType()`, `SNESType`, `SNESNASMSetType()`, `SNESNASMGetType()`, `SNESNASMSetSubdomains()`, `SNESNASMGetSubdomains()`,
833: `SNESNASMGetSubdomainVecs()`, `SNESNASMSetComputeFinalJacobian()`, `SNESNASMSetDamping()`, `SNESNASMGetDamping()`, `SNESNASMSetWeight()`,
834: `SNESNASMGetSNES()`, `SNESNASMGetNumber()`
835: M*/
837: PETSC_EXTERN PetscErrorCode SNESCreate_NASM(SNES snes)
838: {
839: SNES_NASM *nasm;
841: PetscFunctionBegin;
842: PetscCall(PetscNew(&nasm));
843: snes->data = (void *)nasm;
845: nasm->n = PETSC_DECIDE;
846: nasm->subsnes = NULL;
847: nasm->x = NULL;
848: nasm->xl = NULL;
849: nasm->y = NULL;
850: nasm->b = NULL;
851: nasm->oscatter = NULL;
852: nasm->oscatter_copy = NULL;
853: nasm->iscatter = NULL;
854: nasm->gscatter = NULL;
855: nasm->damping = 1.;
857: nasm->type = PC_ASM_BASIC;
858: nasm->finaljacobian = PETSC_FALSE;
859: nasm->weight_set = PETSC_FALSE;
861: snes->ops->destroy = SNESDestroy_NASM;
862: snes->ops->setup = SNESSetUp_NASM;
863: snes->ops->setfromoptions = SNESSetFromOptions_NASM;
864: snes->ops->view = SNESView_NASM;
865: snes->ops->solve = SNESSolve_NASM;
866: snes->ops->reset = SNESReset_NASM;
868: snes->usesksp = PETSC_FALSE;
869: snes->usesnpc = PETSC_FALSE;
871: snes->alwayscomputesfinalresidual = PETSC_FALSE;
873: nasm->fjtype = 0;
874: nasm->xinit = NULL;
875: nasm->eventrestrictinterp = 0;
876: nasm->eventsubsolve = 0;
878: PetscCall(SNESParametersInitialize(snes));
879: PetscObjectParameterSetDefault(snes, max_funcs, 10000);
880: PetscObjectParameterSetDefault(snes, max_its, 10000);
882: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESNASMSetType_C", SNESNASMSetType_NASM));
883: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESNASMGetType_C", SNESNASMGetType_NASM));
884: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESNASMSetSubdomains_C", SNESNASMSetSubdomains_NASM));
885: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESNASMGetSubdomains_C", SNESNASMGetSubdomains_NASM));
886: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESNASMSetDamping_C", SNESNASMSetDamping_NASM));
887: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESNASMGetDamping_C", SNESNASMGetDamping_NASM));
888: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESNASMGetSubdomainVecs_C", SNESNASMGetSubdomainVecs_NASM));
889: PetscCall(PetscObjectComposeFunction((PetscObject)snes, "SNESNASMSetComputeFinalJacobian_C", SNESNASMSetComputeFinalJacobian_NASM));
890: PetscFunctionReturn(PETSC_SUCCESS);
891: }
893: /*@
894: SNESNASMGetSNES - Gets a subsolver
896: Not Collective
898: Input Parameters:
899: + snes - the `SNES` context
900: - i - the number of the subsnes to get
902: Output Parameter:
903: . subsnes - the subsolver context
905: Level: intermediate
907: .seealso: [](ch_snes), `SNESNASM`, `SNESNASMGetNumber()`
908: @*/
909: PetscErrorCode SNESNASMGetSNES(SNES snes, PetscInt i, SNES *subsnes)
910: {
911: SNES_NASM *nasm = (SNES_NASM *)snes->data;
913: PetscFunctionBegin;
914: PetscCheck(i >= 0 && i < nasm->n, PetscObjectComm((PetscObject)snes), PETSC_ERR_ARG_OUTOFRANGE, "No such subsolver");
915: *subsnes = nasm->subsnes[i];
916: PetscFunctionReturn(PETSC_SUCCESS);
917: }
919: /*@
920: SNESNASMGetNumber - Gets number of subsolvers
922: Not Collective
924: Input Parameter:
925: . snes - the `SNES` context
927: Output Parameter:
928: . n - the number of subsolvers
930: Level: intermediate
932: .seealso: [](ch_snes), `SNESNASM`, `SNESNASMGetSNES()`
933: @*/
934: PetscErrorCode SNESNASMGetNumber(SNES snes, PetscInt *n)
935: {
936: SNES_NASM *nasm = (SNES_NASM *)snes->data;
938: PetscFunctionBegin;
939: *n = nasm->n;
940: PetscFunctionReturn(PETSC_SUCCESS);
941: }
943: /*@
944: SNESNASMSetWeight - Sets weight to use when adding overlapping updates
946: Collective
948: Input Parameters:
949: + snes - the `SNES` context
950: - weight - the weights to use (typically 1/N for each dof, where N is the number of patches it appears in)
952: Level: intermediate
954: .seealso: [](ch_snes), `SNESNASM`
955: @*/
956: PetscErrorCode SNESNASMSetWeight(SNES snes, Vec weight)
957: {
958: SNES_NASM *nasm = (SNES_NASM *)snes->data;
960: PetscFunctionBegin;
961: PetscCall(VecDestroy(&nasm->weight));
962: nasm->weight_set = PETSC_TRUE;
963: nasm->weight = weight;
964: PetscCall(PetscObjectReference((PetscObject)nasm->weight));
965: PetscFunctionReturn(PETSC_SUCCESS);
966: }