Actual source code: power.c
1: #include <petsc/private/matimpl.h>
3: static PetscErrorCode MatColoringApply_Power(MatColoring mc, ISColoring *iscoloring)
4: {
5: Mat m = mc->mat, mp, ms;
6: MatColoring imc;
7: PetscInt i;
8: const char *optionsprefix;
10: /* square the matrix repeatedly if necessary */
11: if (mc->dist == 1) {
12: mp = m;
13: } else {
14: MatMatMult(m, m, MAT_INITIAL_MATRIX, 2.0, &mp);
15: for (i = 2; i < mc->dist; i++) {
16: ms = mp;
17: MatMatMult(m, ms, MAT_INITIAL_MATRIX, 2.0, &mp);
18: MatDestroy(&ms);
19: }
20: }
21: MatColoringCreate(mp, &imc);
22: PetscObjectGetOptionsPrefix((PetscObject)mc, &optionsprefix);
23: PetscObjectSetOptionsPrefix((PetscObject)imc, optionsprefix);
24: PetscObjectAppendOptionsPrefix((PetscObject)imc, "power_");
25: MatColoringSetType(imc, MATCOLORINGGREEDY);
26: MatColoringSetDistance(imc, 1);
27: MatColoringSetWeightType(imc, mc->weight_type);
28: MatColoringSetFromOptions(imc);
29: MatColoringApply(imc, iscoloring);
30: MatColoringDestroy(&imc);
31: if (mp != m) MatDestroy(&mp);
32: return 0;
33: }
35: /*MC
36: MATCOLORINGPOWER - Take the matrix's nth power, then do one-coloring on it.
38: Level: beginner
40: Notes:
41: This is merely a trivial test algorithm.
43: Supports any distance coloring.
45: .seealso: `MatColoring`, `MatColoringType`, `MatColoringCreate()`, `MatColoring`, `MatColoringSetType()`
46: M*/
47: PETSC_EXTERN PetscErrorCode MatColoringCreate_Power(MatColoring mc)
48: {
49: mc->ops->apply = MatColoringApply_Power;
50: mc->ops->view = NULL;
51: mc->ops->destroy = NULL;
52: mc->ops->setfromoptions = NULL;
53: return 0;
54: }