Actual source code: ex43.c
1: static char help[] = "Demonstrates the DMLocalToLocal bug in PETSc 3.6.\n\n";
3: /*
4: Use the options
5: -da_grid_x <nx> - number of grid points in x direction, if M < 0
6: -da_grid_y <ny> - number of grid points in y direction, if N < 0
7: -da_processors_x <MX> number of processors in x directio
8: -da_processors_y <MY> number of processors in x direction
10: Contributed by Constantine Khroulev
11: */
13: #include <petscdm.h>
14: #include <petscdmda.h>
16: PetscErrorCode PrintVecWithGhosts(DM da, Vec v)
17: {
18: PetscScalar **p;
19: PetscInt i, j;
20: MPI_Comm com;
21: PetscMPIInt rank;
22: DMDALocalInfo info;
24: com = PetscObjectComm((PetscObject)da);
25: PetscCallMPI(MPI_Comm_rank(com, &rank));
26: PetscCall(DMDAGetLocalInfo(da, &info));
27: PetscCall(PetscSynchronizedPrintf(com, "begin rank %d portion (with ghosts, %" PetscInt_FMT " x %" PetscInt_FMT ")\n", rank, info.gxm, info.gym));
28: PetscCall(DMDAVecGetArray(da, v, &p));
29: for (i = info.gxs; i < info.gxs + info.gxm; i++) {
30: for (j = info.gys; j < info.gys + info.gym; j++) PetscCall(PetscSynchronizedPrintf(com, "%g, ", (double)PetscRealPart(p[j][i])));
31: PetscCall(PetscSynchronizedPrintf(com, "\n"));
32: }
33: PetscCall(DMDAVecRestoreArray(da, v, &p));
34: PetscCall(PetscSynchronizedPrintf(com, "end rank %d portion\n", rank));
35: PetscCall(PetscSynchronizedFlush(com, PETSC_STDOUT));
36: return PETSC_SUCCESS;
37: }
39: /* Set a Vec v to value, but do not touch ghosts. */
40: PetscErrorCode VecSetOwned(DM da, Vec v, PetscScalar value)
41: {
42: PetscScalar **p;
43: PetscInt i, j, xs, xm, ys, ym;
45: PetscCall(DMDAGetCorners(da, &xs, &ys, 0, &xm, &ym, 0));
46: PetscCall(DMDAVecGetArray(da, v, &p));
47: for (i = xs; i < xs + xm; i++) {
48: for (j = ys; j < ys + ym; j++) p[j][i] = value;
49: }
50: PetscCall(DMDAVecRestoreArray(da, v, &p));
51: return PETSC_SUCCESS;
52: }
54: int main(int argc, char **argv)
55: {
56: PetscInt M = 4, N = 3;
57: DM da;
58: Vec local;
59: PetscScalar value = 0.0;
60: DMBoundaryType bx = DM_BOUNDARY_PERIODIC, by = DM_BOUNDARY_PERIODIC;
61: DMDAStencilType stype = DMDA_STENCIL_BOX;
63: PetscFunctionBeginUser;
64: PetscCall(PetscInitialize(&argc, &argv, NULL, help));
65: PetscCall(DMDACreate2d(PETSC_COMM_WORLD, bx, by, stype, M, N, PETSC_DECIDE, PETSC_DECIDE, 1, 1, NULL, NULL, &da));
66: PetscCall(DMSetFromOptions(da));
67: PetscCall(DMSetUp(da));
68: PetscCall(DMCreateLocalVector(da, &local));
70: PetscCall(VecSet(local, value));
71: PetscCall(PetscPrintf(PETSC_COMM_WORLD, "\nAfter setting all values to %d:\n", (int)PetscRealPart(value)));
72: PetscCall(PrintVecWithGhosts(da, local));
73: PetscCall(PetscPrintf(PETSC_COMM_WORLD, "done\n"));
75: value += 1.0;
76: /* set values owned by a process, leaving ghosts alone */
77: PetscCall(VecSetOwned(da, local, value));
79: /* print after re-setting interior values again */
80: PetscCall(PetscPrintf(PETSC_COMM_WORLD, "\nAfter setting interior values to %d:\n", (int)PetscRealPart(value)));
81: PetscCall(PrintVecWithGhosts(da, local));
82: PetscCall(PetscPrintf(PETSC_COMM_WORLD, "done\n"));
84: /* communicate ghosts */
85: PetscCall(DMLocalToLocalBegin(da, local, INSERT_VALUES, local));
86: PetscCall(DMLocalToLocalEnd(da, local, INSERT_VALUES, local));
88: /* print again */
89: PetscCall(PetscPrintf(PETSC_COMM_WORLD, "\nAfter local-to-local communication:\n"));
90: PetscCall(PrintVecWithGhosts(da, local));
91: PetscCall(PetscPrintf(PETSC_COMM_WORLD, "done\n"));
93: /* Free memory */
94: PetscCall(VecDestroy(&local));
95: PetscCall(DMDestroy(&da));
96: PetscCall(PetscFinalize());
97: return 0;
98: }
100: /*TEST
102: test:
103: nsize: 2
105: TEST*/