Actual source code: ex35.c
2: static char help[] = "MatLoad test for loading matrices that are created by DMCreateMatrix() and\n\
3: stored in binary via MatView_MPI_DA.MatView_MPI_DA stores the matrix\n\
4: in natural ordering. Hence MatLoad() has to read the matrix first in\n\
5: natural ordering and then permute it back to the application ordering.This\n\
6: example is used for testing the subroutine MatLoad_MPI_DA\n\n";
8: #include <petscdm.h>
9: #include <petscdmda.h>
11: int main(int argc, char **argv)
12: {
13: PetscInt X = 10, Y = 8, Z = 8;
14: DM da;
15: PetscViewer viewer;
16: Mat A;
18: PetscFunctionBeginUser;
19: PetscCall(PetscInitialize(&argc, &argv, (char *)0, help));
20: PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD, "temp.dat", FILE_MODE_WRITE, &viewer));
22: /* Read options */
23: PetscCall(PetscOptionsGetInt(NULL, NULL, "-X", &X, NULL));
24: PetscCall(PetscOptionsGetInt(NULL, NULL, "-Y", &Y, NULL));
25: PetscCall(PetscOptionsGetInt(NULL, NULL, "-Z", &Z, NULL));
27: /* Create distributed array and get vectors */
28: PetscCall(DMDACreate3d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, DMDA_STENCIL_STAR, X, Y, Z, PETSC_DECIDE, PETSC_DECIDE, PETSC_DECIDE, 1, 1, NULL, NULL, NULL, &da));
29: PetscCall(DMSetFromOptions(da));
30: PetscCall(DMSetUp(da));
31: PetscCall(DMSetMatType(da, MATMPIAIJ));
32: PetscCall(DMCreateMatrix(da, &A));
33: PetscCall(MatShift(A, X));
34: PetscCall(MatView(A, viewer));
35: PetscCall(MatDestroy(&A));
36: PetscCall(PetscViewerDestroy(&viewer));
38: PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD, "temp.dat", FILE_MODE_READ, &viewer));
39: PetscCall(DMCreateMatrix(da, &A));
40: PetscCall(MatLoad(A, viewer));
42: /* Free memory */
43: PetscCall(MatDestroy(&A));
44: PetscCall(PetscViewerDestroy(&viewer));
45: PetscCall(DMDestroy(&da));
46: PetscCall(PetscFinalize());
47: return 0;
48: }