Actual source code: ex38.c
2: static char help[] = "Tests DMGlobalToLocal() for 3d DA with stencil width of 2.\n\n";
4: #include <petscdm.h>
5: #include <petscdmda.h>
7: int main(int argc, char **argv)
8: {
9: PetscInt N = 3, M = 2, P = 4, dof = 1, rstart, rend, i;
10: PetscInt stencil_width = 2;
11: PetscMPIInt rank;
12: DMBoundaryType bx = DM_BOUNDARY_NONE, by = DM_BOUNDARY_NONE, bz = DM_BOUNDARY_NONE;
13: DMDAStencilType stencil_type = DMDA_STENCIL_STAR;
14: DM da;
15: Vec global, local;
17: PetscFunctionBeginUser;
18: PetscCall(PetscInitialize(&argc, &argv, (char *)0, help));
19: PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
20: PetscCall(PetscOptionsGetInt(NULL, NULL, "-M", &M, NULL));
21: PetscCall(PetscOptionsGetInt(NULL, NULL, "-N", &N, NULL));
22: PetscCall(PetscOptionsGetInt(NULL, NULL, "-P", &P, NULL));
23: PetscCall(PetscOptionsGetInt(NULL, NULL, "-dof", &dof, NULL));
24: PetscCall(PetscOptionsGetInt(NULL, NULL, "-stencil_width", &stencil_width, NULL));
25: PetscCall(PetscOptionsGetInt(NULL, NULL, "-stencil_type", (PetscInt *)&stencil_type, NULL));
27: PetscCall(DMDACreate3d(PETSC_COMM_WORLD, bx, by, bz, stencil_type, M, N, P, PETSC_DECIDE, PETSC_DECIDE, PETSC_DECIDE, dof, stencil_width, 0, 0, 0, &da));
28: PetscCall(DMSetFromOptions(da));
29: PetscCall(DMSetUp(da));
30: PetscCall(DMCreateGlobalVector(da, &global));
31: PetscCall(VecGetOwnershipRange(global, &rstart, &rend));
32: for (i = rstart; i < rend; i++) PetscCall(VecSetValue(global, i, (PetscReal)(i + 100 * rank), INSERT_VALUES));
33: PetscCall(VecAssemblyBegin(global));
34: PetscCall(VecAssemblyEnd(global));
35: PetscCall(DMCreateLocalVector(da, &local));
36: PetscCall(VecSet(local, -1));
37: PetscCall(DMGlobalToLocalBegin(da, global, INSERT_VALUES, local));
38: PetscCall(DMGlobalToLocalEnd(da, global, INSERT_VALUES, local));
39: if (rank == 0) PetscCall(VecView(local, 0));
40: PetscCall(DMDestroy(&da));
41: PetscCall(VecDestroy(&local));
42: PetscCall(VecDestroy(&global));
43: PetscCall(PetscFinalize());
44: return 0;
45: }