xref: /petsc/src/dm/tests/ex19.c (revision 9566063d113dddea24716c546802770db7481bc0)
1c4762a1bSJed Brown 
2c4762a1bSJed Brown static char help[] = "Tests DMDA with variable multiple degrees of freedom per node.\n\n";
3c4762a1bSJed Brown 
4c4762a1bSJed Brown /*
5c4762a1bSJed Brown    This code only compiles with gcc, since it is not ANSI C
6c4762a1bSJed Brown */
7c4762a1bSJed Brown 
8c4762a1bSJed Brown #include <petscdm.h>
9c4762a1bSJed Brown #include <petscdmda.h>
10c4762a1bSJed Brown 
11c4762a1bSJed Brown PetscErrorCode doit(DM da,Vec global)
12c4762a1bSJed Brown {
13c4762a1bSJed Brown   PetscErrorCode ierr;
14c4762a1bSJed Brown   PetscInt       i,j,k,M,N,dof;
15c4762a1bSJed Brown 
16*9566063dSJacob Faibussowitsch   PetscCall(DMDAGetInfo(da,0,&M,&N,0,0,0,0,&dof,0,0,0,0,0));
17c4762a1bSJed Brown   {
18c4762a1bSJed Brown     struct {PetscScalar inside[dof];} **mystruct;
19*9566063dSJacob Faibussowitsch     PetscCall(DMDAVecGetArrayRead(da,global,(void*) &mystruct));
20c4762a1bSJed Brown     for (i=0; i<N; i++) {
21c4762a1bSJed Brown       for (j=0; j<M; j++) {
22c4762a1bSJed Brown         for (k=0; k<dof; k++) {
23*9566063dSJacob Faibussowitsch           PetscCall(PetscPrintf(PETSC_COMM_WORLD,"%D %D %g\n",i,j,(double)mystruct[i][j].inside[0]));
24c4762a1bSJed Brown 
25c4762a1bSJed Brown           mystruct[i][j].inside[1] = 2.1;
26c4762a1bSJed Brown         }
27c4762a1bSJed Brown       }
28c4762a1bSJed Brown     }
29*9566063dSJacob Faibussowitsch     PetscCall(DMDAVecRestoreArrayRead(da,global,(void*) &mystruct));
30c4762a1bSJed Brown   }
31c4762a1bSJed Brown   PetscFunctionReturn(0);
32c4762a1bSJed Brown }
33c4762a1bSJed Brown 
34c4762a1bSJed Brown int main(int argc,char **argv)
35c4762a1bSJed Brown {
36c4762a1bSJed Brown   PetscInt       dof = 2,M = 3,N = 3,m = PETSC_DECIDE,n = PETSC_DECIDE;
37c4762a1bSJed Brown   PetscErrorCode ierr;
38c4762a1bSJed Brown   DM             da;
39c4762a1bSJed Brown   Vec            global,local;
40c4762a1bSJed Brown 
41*9566063dSJacob Faibussowitsch   PetscCall(PetscInitialize(&argc,&argv,(char*)0,help));
42*9566063dSJacob Faibussowitsch   PetscCall(PetscOptionsGetInt(NULL,0,"-dof",&dof,0));
43c4762a1bSJed Brown   /* Create distributed array and get vectors */
44*9566063dSJacob Faibussowitsch   PetscCall(DMDACreate2d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE,DMDA_STENCIL_BOX,M,N,m,n,dof,1,NULL,NULL,&da));
45*9566063dSJacob Faibussowitsch   PetscCall(DMSetFromOptions(da));
46*9566063dSJacob Faibussowitsch   PetscCall(DMSetUp(da));
47*9566063dSJacob Faibussowitsch   PetscCall(DMCreateGlobalVector(da,&global));
48*9566063dSJacob Faibussowitsch   PetscCall(DMCreateLocalVector(da,&local));
49c4762a1bSJed Brown 
50*9566063dSJacob Faibussowitsch   PetscCall(doit(da,global));
51c4762a1bSJed Brown 
52*9566063dSJacob Faibussowitsch   PetscCall(VecView(global,0));
53c4762a1bSJed Brown 
54c4762a1bSJed Brown   /* Free memory */
55*9566063dSJacob Faibussowitsch   PetscCall(VecDestroy(&local));
56*9566063dSJacob Faibussowitsch   PetscCall(VecDestroy(&global));
57*9566063dSJacob Faibussowitsch   PetscCall(DMDestroy(&da));
58*9566063dSJacob Faibussowitsch   PetscCall(PetscFinalize());
59b122ec5aSJacob Faibussowitsch   return 0;
60c4762a1bSJed Brown }
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