Actual source code: matcoloring.c

  1: #include <petsc/private/matimpl.h>

  3: PetscFunctionList MatColoringList              = NULL;
  4: PetscBool         MatColoringRegisterAllCalled = PETSC_FALSE;
  5: const char *const MatColoringWeightTypes[]     = {"RANDOM", "LEXICAL", "LF", "SL", "MatColoringWeightType", "MAT_COLORING_WEIGHT_", NULL};

  7: /*@C
  8:   MatColoringRegister - Adds a new sparse matrix coloring to the  matrix package.

 10:   Not Collective, No Fortran Support

 12:   Input Parameters:
 13: + sname    - name of Coloring (for example `MATCOLORINGSL`)
 14: - function - function pointer that creates the coloring

 16:   Level: developer

 18:   Example Usage:
 19: .vb
 20:    MatColoringRegister("my_color", MyColor);
 21: .ve

 23:   Then, your partitioner can be chosen with the procedural interface via `MatColoringSetType(part, "my_color")`  or at runtime via the option
 24:   `-mat_coloring_type my_color`

 26: .seealso: `MatColoringType`, `MatColoringRegisterDestroy()`, `MatColoringRegisterAll()`
 27: @*/
 28: PetscErrorCode MatColoringRegister(const char sname[], PetscErrorCode (*function)(MatColoring))
 29: {
 30:   PetscFunctionBegin;
 31:   PetscCall(MatInitializePackage());
 32:   PetscCall(PetscFunctionListAdd(&MatColoringList, sname, function));
 33:   PetscFunctionReturn(PETSC_SUCCESS);
 34: }

 36: /*@
 37:   MatColoringCreate - Creates a matrix coloring context.

 39:   Collective

 41:   Input Parameter:
 42: . m - MPI communicator

 44:   Output Parameter:
 45: . mcptr - the new `MatColoring` context

 47:   Options Database Keys:
 48: + -mat_coloring_type      - the type of coloring algorithm used. See `MatColoringType`.
 49: . -mat_coloring_maxcolors - the maximum number of relevant colors, all nodes not in a color are in maxcolors+1
 50: . -mat_coloring_distance  - compute a distance 1,2,... coloring.
 51: . -mat_coloring_view      - print information about the coloring and the produced index sets
 52: . -mat_coloring_test      - debugging option that prints all coloring incompatibilities
 53: - -mat_is_coloring_test   - debugging option that throws an error if MatColoringApply() generates an incorrect iscoloring

 55:   Level: beginner

 57:   Notes:
 58:   A distance one coloring is useful, for example, multi-color SOR.

 60:   A distance two coloring is for the finite difference computation of Jacobians (see `MatFDColoringCreate()`).

 62:   Coloring of matrices can be computed directly from the sparse matrix nonzero structure via the `MatColoring` object or from the mesh from which the
 63:   matrix comes from with `DMCreateColoring()`. In general using the mesh produces a more optimal coloring (fewer colors).

 65:   Some coloring types only support distance two colorings

 67: .seealso: `MatColoringSetFromOptions()`, `MatColoring`, `MatColoringApply()`, `MatFDColoringCreate()`, `DMCreateColoring()`, `MatColoringType`
 68: @*/
 69: PetscErrorCode MatColoringCreate(Mat m, MatColoring *mcptr)
 70: {
 71:   MatColoring mc;

 73:   PetscFunctionBegin;
 75:   PetscAssertPointer(mcptr, 2);
 76:   *mcptr = NULL;

 78:   PetscCall(MatInitializePackage());
 79:   PetscCall(PetscHeaderCreate(mc, MAT_COLORING_CLASSID, "MatColoring", "Matrix coloring", "MatColoring", PetscObjectComm((PetscObject)m), MatColoringDestroy, MatColoringView));
 80:   PetscCall(PetscObjectReference((PetscObject)m));
 81:   mc->mat          = m;
 82:   mc->dist         = 2; /* default to Jacobian computation case */
 83:   mc->maxcolors    = IS_COLORING_MAX;
 84:   *mcptr           = mc;
 85:   mc->valid        = PETSC_FALSE;
 86:   mc->weight_type  = MAT_COLORING_WEIGHT_RANDOM;
 87:   mc->user_weights = NULL;
 88:   mc->user_lperm   = NULL;
 89:   PetscFunctionReturn(PETSC_SUCCESS);
 90: }

 92: /*@
 93:   MatColoringDestroy - Destroys the matrix coloring context

 95:   Collective

 97:   Input Parameter:
 98: . mc - the `MatColoring` context

100:   Level: beginner

102: .seealso: `MatColoring`, `MatColoringCreate()`, `MatColoringApply()`
103: @*/
104: PetscErrorCode MatColoringDestroy(MatColoring *mc)
105: {
106:   PetscFunctionBegin;
107:   if (--((PetscObject)*mc)->refct > 0) {
108:     *mc = NULL;
109:     PetscFunctionReturn(PETSC_SUCCESS);
110:   }
111:   PetscCall(MatDestroy(&(*mc)->mat));
112:   PetscTryTypeMethod(*mc, destroy);
113:   PetscCall(PetscFree((*mc)->user_weights));
114:   PetscCall(PetscFree((*mc)->user_lperm));
115:   PetscCall(PetscHeaderDestroy(mc));
116:   PetscFunctionReturn(PETSC_SUCCESS);
117: }

119: /*@
120:   MatColoringSetType - Sets the type of coloring algorithm used

122:   Collective

124:   Input Parameters:
125: + mc   - the `MatColoring` context
126: - type - the type of coloring

128:   Options Database Key:
129: . -mat_coloring_type type - the name of the type

131:   Level: beginner

133:   Note:
134:   Possible types include the sequential types `MATCOLORINGLF`,
135:   `MATCOLORINGSL`, and `MATCOLORINGID` from the MINPACK package as well
136:   as a parallel `MATCOLORINGGREEDY` algorithm.

138: .seealso: `MatColoring`, `MatColoringSetFromOptions()`, `MatColoringType`, `MatColoringCreate()`, `MatColoringApply()`
139: @*/
140: PetscErrorCode MatColoringSetType(MatColoring mc, MatColoringType type)
141: {
142:   PetscBool match;
143:   PetscErrorCode (*r)(MatColoring);

145:   PetscFunctionBegin;
147:   PetscAssertPointer(type, 2);
148:   PetscCall(PetscObjectTypeCompare((PetscObject)mc, type, &match));
149:   if (match) PetscFunctionReturn(PETSC_SUCCESS);
150:   PetscCall(PetscFunctionListFind(MatColoringList, type, &r));
151:   PetscCheck(r, PetscObjectComm((PetscObject)mc), PETSC_ERR_ARG_UNKNOWN_TYPE, "Unable to find requested MatColoring type %s", type);

153:   PetscTryTypeMethod(mc, destroy);
154:   mc->ops->destroy        = NULL;
155:   mc->ops->apply          = NULL;
156:   mc->ops->view           = NULL;
157:   mc->ops->setfromoptions = NULL;
158:   mc->ops->destroy        = NULL;

160:   PetscCall(PetscObjectChangeTypeName((PetscObject)mc, type));
161:   PetscCall((*r)(mc));
162:   PetscFunctionReturn(PETSC_SUCCESS);
163: }

165: /*@
166:   MatColoringSetFromOptions - Sets `MatColoring` options from options database

168:   Collective

170:   Input Parameter:
171: . mc - `MatColoring` context

173:   Options Database Keys:
174: + -mat_coloring_type      - the type of coloring algorithm used. See `MatColoringType`.
175: . -mat_coloring_maxcolors - the maximum number of relevant colors, all nodes not in a color are in maxcolors+1
176: . -mat_coloring_distance  - compute a distance 1,2,... coloring.
177: . -mat_coloring_view      - print information about the coloring and the produced index sets
178: . -snes_fd_color          - instruct SNES to using coloring and then `MatFDColoring` to compute the Jacobians
179: - -snes_fd_color_use_mat  - instruct `SNES` to color the matrix directly instead of the `DM` from which the matrix comes (the default)

181:   Level: beginner

183: .seealso: `MatColoring`, `MatColoringApply()`, `MatColoringSetDistance()`, `MatColoringSetType()`, `SNESComputeJacobianDefaultColor()`, `MatColoringType`
184: @*/
185: PetscErrorCode MatColoringSetFromOptions(MatColoring mc)
186: {
187:   PetscBool       flg;
188:   MatColoringType deft = MATCOLORINGSL;
189:   char            type[256];
190:   PetscInt        dist, maxcolors;

192:   PetscFunctionBegin;
194:   PetscCall(MatColoringGetDistance(mc, &dist));
195:   if (dist == 2) deft = MATCOLORINGSL;
196:   else deft = MATCOLORINGGREEDY;
197:   PetscCall(MatColoringGetMaxColors(mc, &maxcolors));
198:   PetscCall(MatColoringRegisterAll());
199:   PetscObjectOptionsBegin((PetscObject)mc);
200:   if (((PetscObject)mc)->type_name) deft = ((PetscObject)mc)->type_name;
201:   PetscCall(PetscOptionsFList("-mat_coloring_type", "The coloring method used", "MatColoringSetType", MatColoringList, deft, type, 256, &flg));
202:   if (flg) {
203:     PetscCall(MatColoringSetType(mc, type));
204:   } else if (!((PetscObject)mc)->type_name) {
205:     PetscCall(MatColoringSetType(mc, deft));
206:   }
207:   PetscCall(PetscOptionsInt("-mat_coloring_distance", "Distance of the coloring", "MatColoringSetDistance", dist, &dist, &flg));
208:   if (flg) PetscCall(MatColoringSetDistance(mc, dist));
209:   PetscCall(PetscOptionsInt("-mat_coloring_maxcolors", "Maximum colors returned at the end. 1 returns an independent set", "MatColoringSetMaxColors", maxcolors, &maxcolors, &flg));
210:   if (flg) PetscCall(MatColoringSetMaxColors(mc, maxcolors));
211:   PetscTryTypeMethod(mc, setfromoptions, PetscOptionsObject);
212:   PetscCall(PetscOptionsBool("-mat_coloring_test", "Check that a valid coloring has been produced", "", mc->valid, &mc->valid, NULL));
213:   PetscCall(PetscOptionsBool("-mat_is_coloring_test", "Check that a valid iscoloring has been produced", "", mc->valid_iscoloring, &mc->valid_iscoloring, NULL));
214:   PetscCall(PetscOptionsEnum("-mat_coloring_weight_type", "Sets the type of vertex weighting used", "MatColoringSetWeightType", MatColoringWeightTypes, (PetscEnum)mc->weight_type, (PetscEnum *)&mc->weight_type, NULL));
215:   PetscCall(PetscObjectProcessOptionsHandlers((PetscObject)mc, PetscOptionsObject));
216:   PetscOptionsEnd();
217:   PetscFunctionReturn(PETSC_SUCCESS);
218: }

220: /*@
221:   MatColoringSetDistance - Sets the distance of the coloring

223:   Logically Collective

225:   Input Parameters:
226: + mc   - the `MatColoring` context
227: - dist - the distance the coloring should compute

229:   Options Database Key:
230: . -mat_coloring_type - the type of coloring algorithm used. See `MatColoringType`.

232:   Level: beginner

234:   Note:
235:   The distance of the coloring denotes the minimum number
236:   of edges in the graph induced by the matrix any two vertices
237:   of the same color are.  Distance-1 colorings are the classical
238:   coloring, where no two vertices of the same color are adjacent.
239:   distance-2 colorings are useful for the computation of Jacobians.

241: .seealso: `MatColoring`, `MatColoringSetFromOptions()`, `MatColoringGetDistance()`, `MatColoringApply()`
242: @*/
243: PetscErrorCode MatColoringSetDistance(MatColoring mc, PetscInt dist)
244: {
245:   PetscFunctionBegin;
247:   mc->dist = dist;
248:   PetscFunctionReturn(PETSC_SUCCESS);
249: }

251: /*@
252:   MatColoringGetDistance - Gets the distance of the coloring

254:   Logically Collective

256:   Input Parameter:
257: . mc - the `MatColoring` context

259:   Output Parameter:
260: . dist - the current distance being used for the coloring.

262:   Level: beginner

264:   Note:
265:   The distance of the coloring denotes the minimum number
266:   of edges in the graph induced by the matrix any two vertices
267:   of the same color are.  Distance-1 colorings are the classical
268:   coloring, where no two vertices of the same color are adjacent.
269:   distance-2 colorings are useful for the computation of Jacobians.

271: .seealso: `MatColoring`, `MatColoringSetDistance()`, `MatColoringApply()`
272: @*/
273: PetscErrorCode MatColoringGetDistance(MatColoring mc, PetscInt *dist)
274: {
275:   PetscFunctionBegin;
277:   if (dist) *dist = mc->dist;
278:   PetscFunctionReturn(PETSC_SUCCESS);
279: }

281: /*@
282:   MatColoringSetMaxColors - Sets the maximum number of colors to produce

284:   Logically Collective

286:   Input Parameters:
287: + mc        - the `MatColoring` context
288: - maxcolors - the maximum number of colors to produce

290:   Level: beginner

292:   Notes:
293:   Vertices not in an available color are set to have color maxcolors+1, which is not
294:   a valid color as they may be adjacent.

296:   This works only for  `MATCOLORINGGREEDY` and `MATCOLORINGJP`

298:   This may be used to compute a certain number of
299:   independent sets from the graph.  For instance, while using
300:   `MATCOLORINGGREEDY` and maxcolors = 1, one gets out an MIS.

302: .seealso: `MatColoring`, `MatColoringGetMaxColors()`, `MatColoringApply()`
303: @*/
304: PetscErrorCode MatColoringSetMaxColors(MatColoring mc, PetscInt maxcolors)
305: {
306:   PetscFunctionBegin;
308:   mc->maxcolors = maxcolors;
309:   PetscFunctionReturn(PETSC_SUCCESS);
310: }

312: /*@
313:   MatColoringGetMaxColors - Gets the maximum number of colors

315:   Logically Collective

317:   Input Parameter:
318: . mc - the `MatColoring` context

320:   Output Parameter:
321: . maxcolors - the current maximum number of colors to produce

323:   Level: beginner

325: .seealso: `MatColoring`, `MatColoringSetMaxColors()`, `MatColoringApply()`
326: @*/
327: PetscErrorCode MatColoringGetMaxColors(MatColoring mc, PetscInt *maxcolors)
328: {
329:   PetscFunctionBegin;
331:   if (maxcolors) *maxcolors = mc->maxcolors;
332:   PetscFunctionReturn(PETSC_SUCCESS);
333: }

335: /*@
336:   MatColoringApply - Apply the coloring to the matrix, producing index
337:   sets corresponding to a number of independent sets in the induced
338:   graph.

340:   Collective

342:   Input Parameter:
343: . mc - the `MatColoring` context

345:   Output Parameter:
346: . coloring - the `ISColoring` instance containing the coloring

348:   Level: beginner

350: .seealso: `ISColoring`, `MatColoring`, `MatColoringCreate()`
351: @*/
352: PetscErrorCode MatColoringApply(MatColoring mc, ISColoring *coloring)
353: {
354:   PetscBool         flg;
355:   PetscViewerFormat format;
356:   PetscViewer       viewer;
357:   PetscInt          nc, ncolors;

359:   PetscFunctionBegin;
361:   PetscAssertPointer(coloring, 2);
362:   PetscCall(PetscLogEventBegin(MATCOLORING_Apply, mc, 0, 0, 0));
363:   PetscUseTypeMethod(mc, apply, coloring);
364:   PetscCall(PetscLogEventEnd(MATCOLORING_Apply, mc, 0, 0, 0));

366:   /* valid */
367:   if (mc->valid) PetscCall(MatColoringTest(mc, *coloring));
368:   if (mc->valid_iscoloring) PetscCall(MatISColoringTest(mc->mat, *coloring));

370:   /* view */
371:   PetscCall(PetscOptionsGetViewer(PetscObjectComm((PetscObject)mc), ((PetscObject)mc)->options, ((PetscObject)mc)->prefix, "-mat_coloring_view", &viewer, &format, &flg));
372:   if (flg && !PetscPreLoadingOn) {
373:     PetscCall(PetscViewerPushFormat(viewer, format));
374:     PetscCall(MatColoringView(mc, viewer));
375:     PetscCall(MatGetSize(mc->mat, NULL, &nc));
376:     PetscCall(ISColoringGetIS(*coloring, PETSC_USE_POINTER, &ncolors, NULL));
377:     PetscCall(PetscViewerASCIIPrintf(viewer, "  Number of colors %" PetscInt_FMT "\n", ncolors));
378:     PetscCall(PetscViewerASCIIPrintf(viewer, "  Number of total columns %" PetscInt_FMT "\n", nc));
379:     if (nc <= 1000) PetscCall(ISColoringView(*coloring, viewer));
380:     PetscCall(PetscViewerPopFormat(viewer));
381:     PetscCall(PetscOptionsRestoreViewer(&viewer));
382:   }
383:   PetscFunctionReturn(PETSC_SUCCESS);
384: }

386: /*@
387:   MatColoringView - Output details about the `MatColoring`.

389:   Collective

391:   Input Parameters:
392: + mc     - the `MatColoring` context
393: - viewer - the Viewer context

395:   Level: beginner

397: .seealso: `PetscViewer`, `MatColoring`, `MatColoringApply()`
398: @*/
399: PetscErrorCode MatColoringView(MatColoring mc, PetscViewer viewer)
400: {
401:   PetscBool iascii;

403:   PetscFunctionBegin;
405:   if (!viewer) PetscCall(PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)mc), &viewer));
407:   PetscCheckSameComm(mc, 1, viewer, 2);

409:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
410:   if (iascii) {
411:     PetscCall(PetscObjectPrintClassNamePrefixType((PetscObject)mc, viewer));
412:     PetscCall(PetscViewerASCIIPrintf(viewer, "  Weight type: %s\n", MatColoringWeightTypes[mc->weight_type]));
413:     if (mc->maxcolors > 0) {
414:       PetscCall(PetscViewerASCIIPrintf(viewer, "  Distance %" PetscInt_FMT ", Max. Colors %" PetscInt_FMT "\n", mc->dist, mc->maxcolors));
415:     } else {
416:       PetscCall(PetscViewerASCIIPrintf(viewer, "  Distance %" PetscInt_FMT "\n", mc->dist));
417:     }
418:   }
419:   PetscFunctionReturn(PETSC_SUCCESS);
420: }

422: /*@
423:   MatColoringSetWeightType - Set the type of weight computation used while computing the coloring

425:   Logically Collective

427:   Input Parameters:
428: + mc - the `MatColoring` context
429: - wt - the weight type

431:   Level: beginner

433: .seealso: `MatColoring`, `MatColoringWeightType`, `MatColoringApply()`
434: @*/
435: PetscErrorCode MatColoringSetWeightType(MatColoring mc, MatColoringWeightType wt)
436: {
437:   PetscFunctionBegin;
438:   mc->weight_type = wt;
439:   PetscFunctionReturn(PETSC_SUCCESS);
440: }