Actual source code: ex80.c
2: static char help[] = "Partition tiny grid.\n\n";
4: /*
5: Include "petscmat.h" so that we can use matrices. Note that this file
6: automatically includes:
7: petscsys.h - base PETSc routines petscvec.h - vectors
8: petscmat.h - matrices
9: petscis.h - index sets
10: petscviewer.h - viewers
11: */
12: #include <petscmat.h>
14: int main(int argc,char **args)
15: {
16: Mat A;
17: PetscMPIInt rank,size;
18: PetscInt *ia,*ja;
19: MatPartitioning part;
20: IS is,isn;
22: PetscInitialize(&argc,&args,(char*)0,help);
23: MPI_Comm_size(PETSC_COMM_WORLD,&size);
25: MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
27: PetscMalloc1(5,&ia);
28: PetscMalloc1(16,&ja);
29: if (rank == 0) {
30: ja[0] = 1; ja[1] = 4; ja[2] = 0; ja[3] = 2; ja[4] = 5; ja[5] = 1; ja[6] = 3; ja[7] = 6;
31: ja[8] = 2; ja[9] = 7;
32: ia[0] = 0; ia[1] = 2; ia[2] = 5; ia[3] = 8; ia[4] = 10;
33: } else if (rank == 1) {
34: ja[0] = 0; ja[1] = 5; ja[2] = 8; ja[3] = 1; ja[4] = 4; ja[5] = 6; ja[6] = 9; ja[7] = 2;
35: ja[8] = 5; ja[9] = 7; ja[10] = 10; ja[11] = 3; ja[12] = 6; ja[13] = 11;
36: ia[0] = 0; ia[1] = 3; ia[2] = 7; ia[3] = 11; ia[4] = 14;
37: } else if (rank == 2) {
38: ja[0] = 4; ja[1] = 9; ja[2] = 12; ja[3] = 5; ja[4] = 8; ja[5] = 10; ja[6] = 13; ja[7] = 6;
39: ja[8] = 9; ja[9] = 11; ja[10] = 14; ja[11] = 7; ja[12] = 10; ja[13] = 15;
40: ia[0] = 0; ia[1] = 3; ia[2] = 7; ia[3] = 11; ia[4] = 14;
41: } else {
42: ja[0] = 8; ja[1] = 13; ja[2] = 9; ja[3] = 12; ja[4] = 14; ja[5] = 10; ja[6] = 13; ja[7] = 15;
43: ja[8] = 11; ja[9] = 14;
44: ia[0] = 0; ia[1] = 2; ia[2] = 5; ia[3] = 8; ia[4] = 10;
45: }
47: MatCreateMPIAdj(PETSC_COMM_WORLD,4,16,ia,ja,NULL,&A);
48: MatView(A,PETSC_VIEWER_STDOUT_WORLD);
50: /*
51: Partition the graph of the matrix
52: */
53: MatPartitioningCreate(PETSC_COMM_WORLD,&part);
54: MatPartitioningSetAdjacency(part,A);
55: MatPartitioningSetFromOptions(part);
56: /* get new processor owner number of each vertex */
57: MatPartitioningApply(part,&is);
58: /* get new global number of each old global number */
59: ISPartitioningToNumbering(is,&isn);
60: ISView(isn,PETSC_VIEWER_STDOUT_WORLD);
61: ISDestroy(&is);
63: ISDestroy(&isn);
64: MatPartitioningDestroy(&part);
66: /*
67: Free work space. All PETSc objects should be destroyed when they
68: are no longer needed.
69: */
70: MatDestroy(&A);
72: PetscFinalize();
73: return 0;
74: }