xref: /petsc/src/dm/tests/ex43.c (revision 5f80ce2ab25dff0f4601e710601cbbcecf323266)
1c4762a1bSJed Brown static char help[] = "Demonstrates the DMLocalToLocal bug in PETSc 3.6.\n\n";
2c4762a1bSJed Brown 
3c4762a1bSJed Brown /*
4c4762a1bSJed Brown Use the options
5c4762a1bSJed Brown      -da_grid_x <nx> - number of grid points in x direction, if M < 0
6c4762a1bSJed Brown      -da_grid_y <ny> - number of grid points in y direction, if N < 0
7c4762a1bSJed Brown      -da_processors_x <MX> number of processors in x directio
8c4762a1bSJed Brown      -da_processors_y <MY> number of processors in x direction
9c4762a1bSJed Brown 
10c4762a1bSJed Brown   Contributed by Constantine Khroulev
11c4762a1bSJed Brown */
12c4762a1bSJed Brown 
13c4762a1bSJed Brown #include <petscdm.h>
14c4762a1bSJed Brown #include <petscdmda.h>
15c4762a1bSJed Brown 
16c4762a1bSJed Brown PetscErrorCode PrintVecWithGhosts(DM da, Vec v)
17c4762a1bSJed Brown {
18c4762a1bSJed Brown   PetscScalar    **p;
19c4762a1bSJed Brown   PetscInt       i, j;
20c4762a1bSJed Brown   MPI_Comm       com;
21c4762a1bSJed Brown   PetscMPIInt    rank;
22c4762a1bSJed Brown   DMDALocalInfo  info;
23c4762a1bSJed Brown 
24c4762a1bSJed Brown   com = PetscObjectComm((PetscObject)da);
25*5f80ce2aSJacob Faibussowitsch   CHKERRMPI(MPI_Comm_rank(com, &rank));
26*5f80ce2aSJacob Faibussowitsch   CHKERRQ(DMDAGetLocalInfo(da, &info));
27*5f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscSynchronizedPrintf(com, "begin rank %d portion (with ghosts, %D x %D)\n",rank, info.gxm, info.gym));
28*5f80ce2aSJacob Faibussowitsch   CHKERRQ(DMDAVecGetArray(da, v, &p));
29c4762a1bSJed Brown   for (i = info.gxs; i < info.gxs + info.gxm; i++) {
30c4762a1bSJed Brown     for (j = info.gys; j < info.gys + info.gym; j++) {
31*5f80ce2aSJacob Faibussowitsch       CHKERRQ(PetscSynchronizedPrintf(com, "%g, ", (double) PetscRealPart(p[j][i])));
32c4762a1bSJed Brown     }
33*5f80ce2aSJacob Faibussowitsch     CHKERRQ(PetscSynchronizedPrintf(com, "\n"));
34c4762a1bSJed Brown   }
35*5f80ce2aSJacob Faibussowitsch   CHKERRQ(DMDAVecRestoreArray(da, v, &p));
36*5f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscSynchronizedPrintf(com, "end rank %d portion\n", rank));
37*5f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscSynchronizedFlush(com, PETSC_STDOUT));
38c4762a1bSJed Brown   return 0;
39c4762a1bSJed Brown }
40c4762a1bSJed Brown 
41c4762a1bSJed Brown /* Set a Vec v to value, but do not touch ghosts. */
42c4762a1bSJed Brown PetscErrorCode VecSetOwned(DM da, Vec v, PetscScalar value)
43c4762a1bSJed Brown {
44c4762a1bSJed Brown   PetscScalar    **p;
45c4762a1bSJed Brown   PetscInt         i, j, xs, xm, ys, ym;
46c4762a1bSJed Brown 
47*5f80ce2aSJacob Faibussowitsch   CHKERRQ(DMDAGetCorners(da, &xs, &ys, 0, &xm, &ym, 0));
48*5f80ce2aSJacob Faibussowitsch   CHKERRQ(DMDAVecGetArray(da, v, &p));
49c4762a1bSJed Brown   for (i = xs; i < xs + xm; i++) {
50c4762a1bSJed Brown     for (j = ys; j < ys + ym; j++) {
51c4762a1bSJed Brown       p[j][i] = value;
52c4762a1bSJed Brown     }
53c4762a1bSJed Brown   }
54*5f80ce2aSJacob Faibussowitsch   CHKERRQ(DMDAVecRestoreArray(da, v, &p));
55c4762a1bSJed Brown   return 0;
56c4762a1bSJed Brown }
57c4762a1bSJed Brown 
58c4762a1bSJed Brown int main(int argc, char **argv)
59c4762a1bSJed Brown {
60c4762a1bSJed Brown   PetscInt         M = 4, N = 3;
61c4762a1bSJed Brown   PetscErrorCode   ierr;
62c4762a1bSJed Brown   DM               da;
63c4762a1bSJed Brown   Vec              local;
64c4762a1bSJed Brown   PetscScalar      value = 0.0;
65c4762a1bSJed Brown   DMBoundaryType   bx    = DM_BOUNDARY_PERIODIC, by = DM_BOUNDARY_PERIODIC;
66c4762a1bSJed Brown   DMDAStencilType  stype = DMDA_STENCIL_BOX;
67c4762a1bSJed Brown 
68c4762a1bSJed Brown   ierr = PetscInitialize(&argc, &argv, (char*)0, help);if (ierr) return ierr;
69*5f80ce2aSJacob Faibussowitsch   CHKERRQ(DMDACreate2d(PETSC_COMM_WORLD,bx,by,stype,M,N,PETSC_DECIDE,PETSC_DECIDE,1,1,NULL,NULL,&da));
70*5f80ce2aSJacob Faibussowitsch   CHKERRQ(DMSetFromOptions(da));
71*5f80ce2aSJacob Faibussowitsch   CHKERRQ(DMSetUp(da));
72*5f80ce2aSJacob Faibussowitsch   CHKERRQ(DMCreateLocalVector(da, &local));
73c4762a1bSJed Brown 
74*5f80ce2aSJacob Faibussowitsch   CHKERRQ(VecSet(local, value));
75*5f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscPrintf(PETSC_COMM_WORLD, "\nAfter setting all values to %d:\n", (int)PetscRealPart(value)));
76*5f80ce2aSJacob Faibussowitsch   CHKERRQ(PrintVecWithGhosts(da, local));
77*5f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscPrintf(PETSC_COMM_WORLD, "done\n"));
78c4762a1bSJed Brown 
79c4762a1bSJed Brown   value += 1.0;
80c4762a1bSJed Brown   /* set values owned by a process, leaving ghosts alone */
81*5f80ce2aSJacob Faibussowitsch   CHKERRQ(VecSetOwned(da, local, value));
82c4762a1bSJed Brown 
83c4762a1bSJed Brown   /* print after re-setting interior values again */
84*5f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscPrintf(PETSC_COMM_WORLD, "\nAfter setting interior values to %d:\n", (int)PetscRealPart(value)));
85*5f80ce2aSJacob Faibussowitsch   CHKERRQ(PrintVecWithGhosts(da, local));
86*5f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscPrintf(PETSC_COMM_WORLD, "done\n"));
87c4762a1bSJed Brown 
88c4762a1bSJed Brown   /* communicate ghosts */
89*5f80ce2aSJacob Faibussowitsch   CHKERRQ(DMLocalToLocalBegin(da, local, INSERT_VALUES, local));
90*5f80ce2aSJacob Faibussowitsch   CHKERRQ(DMLocalToLocalEnd(da, local, INSERT_VALUES, local));
91c4762a1bSJed Brown 
92c4762a1bSJed Brown   /* print again */
93*5f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscPrintf(PETSC_COMM_WORLD, "\nAfter local-to-local communication:\n"));
94*5f80ce2aSJacob Faibussowitsch   CHKERRQ(PrintVecWithGhosts(da, local));
95*5f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscPrintf(PETSC_COMM_WORLD, "done\n"));
96c4762a1bSJed Brown 
97c4762a1bSJed Brown   /* Free memory */
98*5f80ce2aSJacob Faibussowitsch   CHKERRQ(VecDestroy(&local));
99*5f80ce2aSJacob Faibussowitsch   CHKERRQ(DMDestroy(&da));
100c4762a1bSJed Brown   ierr = PetscFinalize();
101c4762a1bSJed Brown   return ierr;
102c4762a1bSJed Brown }
103c4762a1bSJed Brown 
104c4762a1bSJed Brown /*TEST
105c4762a1bSJed Brown 
106c4762a1bSJed Brown    test:
107c4762a1bSJed Brown       nsize: 2
108c4762a1bSJed Brown 
109c4762a1bSJed Brown TEST*/
110