Actual source code: ex38.c
petsc-3.13.6 2020-09-29
2: static char help[] = "Tests DMGlobalToLocal() for 3d DA with stencil width of 2.\n\n";
4: #include <petscdm.h>
5: #include <petscdmda.h>
7: int main(int argc,char **argv)
8: {
9: PetscInt N = 3,M=2,P=4,dof=1,rstart,rend,i;
10: PetscInt stencil_width = 2;
11: PetscErrorCode ierr;
12: PetscMPIInt rank;
13: DMBoundaryType bx = DM_BOUNDARY_NONE,by = DM_BOUNDARY_NONE,bz = DM_BOUNDARY_NONE;
14: DMDAStencilType stencil_type = DMDA_STENCIL_STAR;
15: DM da;
16: Vec global,local;
19: PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
20: MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
21: PetscOptionsGetInt(NULL,NULL,"-M",&M,NULL);
22: PetscOptionsGetInt(NULL,NULL,"-N",&N,NULL);
23: PetscOptionsGetInt(NULL,NULL,"-P",&P,NULL);
24: PetscOptionsGetInt(NULL,NULL,"-dof",&dof,NULL);
25: PetscOptionsGetInt(NULL,NULL,"-stencil_width",&stencil_width,NULL);
26: PetscOptionsGetInt(NULL,NULL,"-stencil_type",(PetscInt*)&stencil_type,NULL);
28: DMDACreate3d(PETSC_COMM_WORLD,bx,by,bz,stencil_type,M,N,P,PETSC_DECIDE,PETSC_DECIDE,PETSC_DECIDE,dof,stencil_width,0,0,0,&da);
29: DMSetFromOptions(da);
30: DMSetUp(da);
31: DMCreateGlobalVector(da,&global);
32: VecGetOwnershipRange(global,&rstart,&rend);
33: for (i=rstart; i<rend; i++) {VecSetValue(global,i,(PetscReal)(i + 100*rank),INSERT_VALUES);}
34: VecAssemblyBegin(global);
35: VecAssemblyEnd(global);
36: DMCreateLocalVector(da,&local);
37: VecSet(local,-1);
38: DMGlobalToLocalBegin(da,global,INSERT_VALUES,local);
39: DMGlobalToLocalEnd(da,global,INSERT_VALUES,local);
40: if (!rank) {VecView(local,0);}
41: DMDestroy(&da);
42: VecDestroy(&local);
43: VecDestroy(&global);
44: PetscFinalize();
45: return ierr;
46: }