Actual source code: ex11.c
petsc-3.12.5 2020-03-29
2: static char help[] = "Tests MatMeshToDual()\n\n";
4: /*T
5: Concepts: Mat^mesh partitioning
6: Processors: n
7: T*/
9: /*
10: Include "petscmat.h" so that we can use matrices.
11: automatically includes:
12: petscsys.h - base PETSc routines petscvec.h - vectors
13: petscmat.h - matrices
14: petscis.h - index sets petscviewer.h - viewers
15: */
16: #include <petscmat.h>
18: int main(int argc,char **args)
19: {
20: Mat mesh,dual;
21: PetscErrorCode ierr;
22: PetscInt Nvertices = 6; /* total number of vertices */
23: PetscInt ncells = 2; /* number cells on this process */
24: PetscInt *ii,*jj;
25: PetscMPIInt size,rank;
26: MatPartitioning part;
27: IS is;
29: PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
30: MPI_Comm_size(MPI_COMM_WORLD,&size);
31: if (size != 2) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_SUP,"This example is for exactly two processes");
32: MPI_Comm_rank(MPI_COMM_WORLD,&rank);
34: PetscMalloc1(3,&ii);
35: PetscMalloc1(6,&jj);
36: ii[0] = 0; ii[1] = 3; ii[2] = 6;
37: if (!rank) {
38: jj[0] = 0; jj[1] = 1; jj[2] = 2; jj[3] = 1; jj[4] = 2; jj[5] = 3;
39: } else {
40: jj[0] = 1; jj[1] = 4; jj[2] = 5; jj[3] = 1; jj[4] = 3; jj[5] = 5;
41: }
42: MatCreateMPIAdj(MPI_COMM_WORLD,ncells,Nvertices,ii,jj,NULL,&mesh);
43: MatMeshToCellGraph(mesh,2,&dual);
44: MatView(dual,PETSC_VIEWER_STDOUT_WORLD);
46: MatPartitioningCreate(MPI_COMM_WORLD,&part);
47: MatPartitioningSetAdjacency(part,dual);
48: MatPartitioningSetFromOptions(part);
49: MatPartitioningApply(part,&is);
50: ISView(is,PETSC_VIEWER_STDOUT_WORLD);
51: ISDestroy(&is);
52: MatPartitioningDestroy(&part);
54: MatDestroy(&mesh);
55: MatDestroy(&dual);
56: PetscFinalize();
57: return ierr;
58: }
64: /*TEST
66: build:
67: requires: parmetis
69: test:
70: nsize: 2
71: requires: parmetis
73: TEST*/