xref: /petsc/src/dm/tests/ex14.c (revision 40badf4fbc550ac1f60bd080eaff6de6d55b946d)
1 
2 static char help[] = "Tests saving DMDA vectors to files.\n\n";
3 
4 /*
5     ex13.c reads in the DMDA and vector written by this program.
6 */
7 
8 #include <petscdm.h>
9 #include <petscdmda.h>
10 
11 int main(int argc,char **argv)
12 {
13   PetscMPIInt    rank;
14   PetscInt       M = 10,N = 8,m = PETSC_DECIDE,n = PETSC_DECIDE, dof = 1;
15   PetscErrorCode ierr;
16   DM             da;
17   Vec            local,global,natural;
18   PetscScalar    value;
19   PetscViewer    bviewer;
20 
21   ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
22   CHKERRQ(PetscOptionsGetInt(NULL,NULL,"-M",&M,NULL));
23   CHKERRQ(PetscOptionsGetInt(NULL,NULL,"-N",&N,NULL));
24   CHKERRQ(PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL));
25   CHKERRQ(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL));
26   CHKERRQ(PetscOptionsGetInt(NULL,NULL,"-dof",&dof,NULL));
27 
28   /* Create distributed array and get vectors */
29   CHKERRQ(DMDACreate2d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE,DMDA_STENCIL_BOX,M,N,m,n,dof,1,NULL,NULL,&da));
30   CHKERRQ(DMSetFromOptions(da));
31   CHKERRQ(DMSetUp(da));
32   CHKERRQ(DMCreateGlobalVector(da,&global));
33   CHKERRQ(DMCreateLocalVector(da,&local));
34 
35   value = -3.0;
36   CHKERRQ(VecSet(global,value));
37   CHKERRQ(DMGlobalToLocalBegin(da,global,INSERT_VALUES,local));
38   CHKERRQ(DMGlobalToLocalEnd(da,global,INSERT_VALUES,local));
39 
40   CHKERRMPI(MPI_Comm_rank(PETSC_COMM_WORLD,&rank));
41   value = rank+1;
42   CHKERRQ(VecScale(local,value));
43   CHKERRQ(DMLocalToGlobalBegin(da,local,ADD_VALUES,global));
44   CHKERRQ(DMLocalToGlobalEnd(da,local,ADD_VALUES,global));
45 
46   CHKERRQ(DMDACreateNaturalVector(da,&natural));
47   CHKERRQ(DMDAGlobalToNaturalBegin(da,global,INSERT_VALUES,natural));
48   CHKERRQ(DMDAGlobalToNaturalEnd(da,global,INSERT_VALUES,natural));
49 
50   CHKERRQ(DMDASetFieldName(da,0,"First field"));
51   /*  CHKERRQ(VecView(global,PETSC_VIEWER_DRAW_WORLD)); */
52 
53   CHKERRQ(PetscViewerBinaryOpen(PETSC_COMM_WORLD,"daoutput",FILE_MODE_WRITE,&bviewer));
54   CHKERRQ(DMView(da,bviewer));
55   CHKERRQ(VecView(global,bviewer));
56   CHKERRQ(PetscViewerDestroy(&bviewer));
57 
58   /* Free memory */
59   CHKERRQ(VecDestroy(&local));
60   CHKERRQ(VecDestroy(&global));
61   CHKERRQ(VecDestroy(&natural));
62   CHKERRQ(DMDestroy(&da));
63   ierr = PetscFinalize();
64   return ierr;
65 }
66