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:   PetscCall(MatInitializePackage());

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

 91: /*@
 92:   MatColoringDestroy - Destroys the matrix coloring context

 94:   Collective

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

 99:   Level: beginner

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

118: /*@
119:   MatColoringSetType - Sets the type of coloring algorithm used

121:   Collective

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

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

130:   Level: beginner

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

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

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

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

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

164: /*@
165:   MatColoringSetFromOptions - Sets `MatColoring` options from options database

167:   Collective

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

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

180:   Level: beginner

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

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

218: /*@
219:   MatColoringSetDistance - Sets the distance of the coloring

221:   Logically Collective

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

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

230:   Level: beginner

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

239: .seealso: `MatColoring`, `MatColoringSetFromOptions()`, `MatColoringGetDistance()`, `MatColoringApply()`
240: @*/
241: PetscErrorCode MatColoringSetDistance(MatColoring mc, PetscInt dist)
242: {
243:   PetscFunctionBegin;
245:   mc->dist = dist;
246:   PetscFunctionReturn(PETSC_SUCCESS);
247: }

249: /*@
250:   MatColoringGetDistance - Gets the distance of the coloring

252:   Logically Collective

254:   Input Parameter:
255: . mc - the `MatColoring` context

257:   Output Parameter:
258: . dist - the current distance being used for the coloring.

260:   Level: beginner

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

269: .seealso: `MatColoring`, `MatColoringSetDistance()`, `MatColoringApply()`
270: @*/
271: PetscErrorCode MatColoringGetDistance(MatColoring mc, PetscInt *dist)
272: {
273:   PetscFunctionBegin;
275:   if (dist) *dist = mc->dist;
276:   PetscFunctionReturn(PETSC_SUCCESS);
277: }

279: /*@
280:   MatColoringSetMaxColors - Sets the maximum number of colors to produce

282:   Logically Collective

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

288:   Level: beginner

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

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

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

300: .seealso: `MatColoring`, `MatColoringGetMaxColors()`, `MatColoringApply()`
301: @*/
302: PetscErrorCode MatColoringSetMaxColors(MatColoring mc, PetscInt maxcolors)
303: {
304:   PetscFunctionBegin;
306:   mc->maxcolors = maxcolors;
307:   PetscFunctionReturn(PETSC_SUCCESS);
308: }

310: /*@
311:   MatColoringGetMaxColors - Gets the maximum number of colors

313:   Logically Collective

315:   Input Parameter:
316: . mc - the `MatColoring` context

318:   Output Parameter:
319: . maxcolors - the current maximum number of colors to produce

321:   Level: beginner

323: .seealso: `MatColoring`, `MatColoringSetMaxColors()`, `MatColoringApply()`
324: @*/
325: PetscErrorCode MatColoringGetMaxColors(MatColoring mc, PetscInt *maxcolors)
326: {
327:   PetscFunctionBegin;
329:   if (maxcolors) *maxcolors = mc->maxcolors;
330:   PetscFunctionReturn(PETSC_SUCCESS);
331: }

333: /*@
334:   MatColoringApply - Apply the coloring to the matrix, producing index
335:   sets corresponding to a number of independent sets in the induced
336:   graph.

338:   Collective

340:   Input Parameter:
341: . mc - the `MatColoring` context

343:   Output Parameter:
344: . coloring - the `ISColoring` instance containing the coloring

346:   Level: beginner

348: .seealso: `ISColoring`, `MatColoring`, `MatColoringCreate()`
349: @*/
350: PetscErrorCode MatColoringApply(MatColoring mc, ISColoring *coloring)
351: {
352:   PetscBool         flg;
353:   PetscViewerFormat format;
354:   PetscViewer       viewer;
355:   PetscInt          nc, ncolors;

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

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

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

384: /*@
385:   MatColoringView - Output details about the `MatColoring`.

387:   Collective

389:   Input Parameters:
390: + mc     - the `MatColoring` context
391: - viewer - the Viewer context

393:   Level: beginner

395: .seealso: `PetscViewer`, `MatColoring`, `MatColoringApply()`
396: @*/
397: PetscErrorCode MatColoringView(MatColoring mc, PetscViewer viewer)
398: {
399:   PetscBool iascii;

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

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

420: /*@
421:   MatColoringSetWeightType - Set the type of weight computation used while computing the coloring

423:   Logically Collective

425:   Input Parameters:
426: + mc - the `MatColoring` context
427: - wt - the weight type

429:   Level: beginner

431: .seealso: `MatColoring`, `MatColoringWeightType`, `MatColoringApply()`
432: @*/
433: PetscErrorCode MatColoringSetWeightType(MatColoring mc, MatColoringWeightType wt)
434: {
435:   PetscFunctionBegin;
436:   mc->weight_type = wt;
437:   PetscFunctionReturn(PETSC_SUCCESS);
438: }