Actual source code: power.c
petsc-3.11.4 2019-09-28
1: #include <petsc/private/matimpl.h>
3: static PetscErrorCode MatColoringApply_Power(MatColoring mc,ISColoring *iscoloring)
4: {
5: PetscErrorCode ierr;
6: Mat m = mc->mat,mp,ms;
7: MatColoring imc;
8: PetscInt i;
9: const char *optionsprefix;
12: /* square the matrix repeatedly if necessary */
13: if (mc->dist == 1) {
14: mp = m;
15: } else {
16: MatMatMult(m,m,MAT_INITIAL_MATRIX,2.0,&mp);
17: for (i=2;i<mc->dist;i++) {
18: ms = mp;
19: MatMatMult(m,ms,MAT_INITIAL_MATRIX,2.0,&mp);
20: MatDestroy(&ms);
21: }
22: }
23: MatColoringCreate(mp,&imc);
24: PetscObjectGetOptionsPrefix((PetscObject)mc,&optionsprefix);
25: PetscObjectSetOptionsPrefix((PetscObject)imc,optionsprefix);
26: PetscObjectAppendOptionsPrefix((PetscObject)imc,"power_");
27: MatColoringSetType(imc,MATCOLORINGGREEDY);
28: MatColoringSetDistance(imc,1);
29: MatColoringSetWeightType(imc,mc->weight_type);
30: MatColoringSetFromOptions(imc);
31: MatColoringApply(imc,iscoloring);
32: MatColoringDestroy(&imc);
33: if (mp != m) {MatDestroy(&mp);}
34: return(0);
35: }
37: /*MC
38: MATCOLORINGPOWER - Take the matrix's nth power, then do one-coloring on it.
40: Level: beginner
42: Notes:
43: This is merely a trivial test algorithm.
45: Supports any distance coloring.
47: .seealso: MatColoringCreate(), MatColoring, MatColoringSetType()
48: M*/
49: PETSC_EXTERN PetscErrorCode MatColoringCreate_Power(MatColoring mc)
50: {
52: mc->ops->apply = MatColoringApply_Power;
53: mc->ops->view = NULL;
54: mc->ops->destroy = NULL;
55: mc->ops->setfromoptions = NULL;
56: return(0);
57: }