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 DM da; 16 Vec local,global,natural; 17 PetscScalar value; 18 PetscViewer bviewer; 19 20 PetscFunctionBeginUser; 21 PetscCall(PetscInitialize(&argc,&argv,(char*)0,help)); 22 PetscCall(PetscOptionsGetInt(NULL,NULL,"-M",&M,NULL)); 23 PetscCall(PetscOptionsGetInt(NULL,NULL,"-N",&N,NULL)); 24 PetscCall(PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL)); 25 PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL)); 26 PetscCall(PetscOptionsGetInt(NULL,NULL,"-dof",&dof,NULL)); 27 28 /* Create distributed array and get vectors */ 29 PetscCall(DMDACreate2d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE,DMDA_STENCIL_BOX,M,N,m,n,dof,1,NULL,NULL,&da)); 30 PetscCall(DMSetFromOptions(da)); 31 PetscCall(DMSetUp(da)); 32 PetscCall(DMCreateGlobalVector(da,&global)); 33 PetscCall(DMCreateLocalVector(da,&local)); 34 35 value = -3.0; 36 PetscCall(VecSet(global,value)); 37 PetscCall(DMGlobalToLocalBegin(da,global,INSERT_VALUES,local)); 38 PetscCall(DMGlobalToLocalEnd(da,global,INSERT_VALUES,local)); 39 40 PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD,&rank)); 41 value = rank+1; 42 PetscCall(VecScale(local,value)); 43 PetscCall(DMLocalToGlobalBegin(da,local,ADD_VALUES,global)); 44 PetscCall(DMLocalToGlobalEnd(da,local,ADD_VALUES,global)); 45 46 PetscCall(DMDACreateNaturalVector(da,&natural)); 47 PetscCall(DMDAGlobalToNaturalBegin(da,global,INSERT_VALUES,natural)); 48 PetscCall(DMDAGlobalToNaturalEnd(da,global,INSERT_VALUES,natural)); 49 50 PetscCall(DMDASetFieldName(da,0,"First field")); 51 /* PetscCall(VecView(global,PETSC_VIEWER_DRAW_WORLD)); */ 52 53 PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD,"daoutput",FILE_MODE_WRITE,&bviewer)); 54 PetscCall(DMView(da,bviewer)); 55 PetscCall(VecView(global,bviewer)); 56 PetscCall(PetscViewerDestroy(&bviewer)); 57 58 /* Free memory */ 59 PetscCall(VecDestroy(&local)); 60 PetscCall(VecDestroy(&global)); 61 PetscCall(VecDestroy(&natural)); 62 PetscCall(DMDestroy(&da)); 63 PetscCall(PetscFinalize()); 64 return 0; 65 } 66