1 static char help[] = "Tests DMDAGetElements() and VecView() contour plotting for 2d DMDAs.\n\n";
2
3 #include <petscdm.h>
4 #include <petscdmda.h>
5 #include <petscdraw.h>
6
main(int argc,char ** argv)7 int main(int argc, char **argv)
8 {
9 PetscInt M = 10, N = 8, ne, nc, i;
10 const PetscInt *e;
11 PetscBool flg = PETSC_FALSE;
12 DM da;
13 PetscViewer viewer;
14 Vec local, global;
15 PetscScalar value;
16 DMBoundaryType bx = DM_BOUNDARY_NONE, by = DM_BOUNDARY_NONE;
17 DMDAStencilType stype = DMDA_STENCIL_BOX;
18 PetscScalar *lv;
19
20 PetscFunctionBeginUser;
21 PetscCall(PetscInitialize(&argc, &argv, NULL, help));
22 PetscCall(PetscViewerDrawOpen(PETSC_COMM_WORLD, 0, "", 300, 0, 300, 300, &viewer));
23
24 /* Read options */
25 PetscCall(PetscOptionsGetInt(NULL, NULL, "-M", &M, NULL));
26 PetscCall(PetscOptionsGetInt(NULL, NULL, "-N", &N, NULL));
27 PetscCall(PetscOptionsGetBool(NULL, NULL, "-star_stencil", &flg, NULL));
28 if (flg) stype = DMDA_STENCIL_STAR;
29
30 /* Create distributed array and get vectors */
31 PetscCall(DMDACreate2d(PETSC_COMM_WORLD, bx, by, stype, M, N, PETSC_DECIDE, PETSC_DECIDE, 1, 1, NULL, NULL, &da));
32 PetscCall(DMSetFromOptions(da));
33 PetscCall(DMSetUp(da));
34 PetscCall(DMCreateGlobalVector(da, &global));
35 PetscCall(DMCreateLocalVector(da, &local));
36
37 value = -3.0;
38 PetscCall(VecSet(global, value));
39 PetscCall(DMGlobalToLocalBegin(da, global, INSERT_VALUES, local));
40 PetscCall(DMGlobalToLocalEnd(da, global, INSERT_VALUES, local));
41
42 PetscCall(DMDASetElementType(da, DMDA_ELEMENT_P1));
43 PetscCall(DMDAGetElements(da, &ne, &nc, &e));
44 PetscCall(VecGetArray(local, &lv));
45 for (i = 0; i < ne; i++) {
46 PetscCall(PetscSynchronizedPrintf(PETSC_COMM_WORLD, "i %" PetscInt_FMT " e[3*i] %" PetscInt_FMT " %" PetscInt_FMT " %" PetscInt_FMT "\n", i, e[3 * i], e[3 * i + 1], e[3 * i + 2]));
47 lv[e[3 * i]] = i;
48 }
49 PetscCall(PetscSynchronizedFlush(PETSC_COMM_WORLD, stdout));
50 PetscCall(VecRestoreArray(local, &lv));
51 PetscCall(DMDARestoreElements(da, &ne, &nc, &e));
52
53 PetscCall(DMLocalToGlobalBegin(da, local, ADD_VALUES, global));
54 PetscCall(DMLocalToGlobalEnd(da, local, ADD_VALUES, global));
55
56 PetscCall(DMView(da, viewer));
57 PetscCall(VecView(global, viewer));
58
59 /* Free memory */
60 PetscCall(PetscViewerDestroy(&viewer));
61 PetscCall(VecDestroy(&local));
62 PetscCall(VecDestroy(&global));
63 PetscCall(DMDestroy(&da));
64 PetscCall(PetscFinalize());
65 return 0;
66 }
67
68 /*TEST
69
70 test:
71 requires: x
72
73 test:
74 suffix: 2
75 nsize: 2
76 requires: x
77
78 TEST*/
79