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 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, (char *)0, 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