1 2 static char help[] = "Tests DMDAGlobalToNaturalAllCreate() using contour plotting for 2d DMDAs.\n\n"; 3 4 #include <petscdm.h> 5 #include <petscdmda.h> 6 #include <petscdraw.h> 7 8 int main(int argc,char **argv) 9 { 10 PetscInt i,j,M = 10,N = 8,m = PETSC_DECIDE,n = PETSC_DECIDE; 11 PetscMPIInt rank; 12 PetscBool flg = PETSC_FALSE; 13 DM da; 14 PetscViewer viewer; 15 Vec localall,global; 16 PetscScalar value,*vlocal; 17 DMBoundaryType bx = DM_BOUNDARY_NONE,by = DM_BOUNDARY_NONE; 18 DMDAStencilType stype = DMDA_STENCIL_BOX; 19 VecScatter tolocalall,fromlocalall; 20 PetscInt start,end; 21 22 PetscCall(PetscInitialize(&argc,&argv,(char*)0,help)); 23 PetscCall(PetscViewerDrawOpen(PETSC_COMM_WORLD,0,"",300,0,300,300,&viewer)); 24 25 /* Read options */ 26 PetscCall(PetscOptionsGetInt(NULL,NULL,"-M",&M,NULL)); 27 PetscCall(PetscOptionsGetInt(NULL,NULL,"-N",&N,NULL)); 28 PetscCall(PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL)); 29 PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL)); 30 PetscCall(PetscOptionsGetBool(NULL,NULL,"-star_stencil",&flg,NULL)); 31 if (flg) stype = DMDA_STENCIL_STAR; 32 33 /* Create distributed array and get vectors */ 34 PetscCall(DMDACreate2d(PETSC_COMM_WORLD,bx,by,stype,M,N,m,n,1,1,NULL,NULL,&da)); 35 PetscCall(DMSetFromOptions(da)); 36 PetscCall(DMSetUp(da)); 37 38 PetscCall(DMCreateGlobalVector(da,&global)); 39 PetscCall(VecCreateSeq(PETSC_COMM_SELF,M*N,&localall)); 40 41 PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD,&rank)); 42 PetscCall(VecGetOwnershipRange(global,&start,&end)); 43 for (i=start; i<end; i++) { 44 value = 5.0*rank; 45 PetscCall(VecSetValues(global,1,&i,&value,INSERT_VALUES)); 46 } 47 PetscCall(VecView(global,viewer)); 48 49 /* 50 Create Scatter from global DMDA parallel vector to local vector that 51 contains all entries 52 */ 53 PetscCall(DMDAGlobalToNaturalAllCreate(da,&tolocalall)); 54 PetscCall(DMDANaturalAllToGlobalCreate(da,&fromlocalall)); 55 56 PetscCall(VecScatterBegin(tolocalall,global,localall,INSERT_VALUES,SCATTER_FORWARD)); 57 PetscCall(VecScatterEnd(tolocalall,global,localall,INSERT_VALUES,SCATTER_FORWARD)); 58 59 PetscCall(VecGetArray(localall,&vlocal)); 60 for (j=0; j<N; j++) { 61 for (i=0; i<M; i++) { 62 *vlocal++ += i + j*M; 63 } 64 } 65 PetscCall(VecRestoreArray(localall,&vlocal)); 66 67 /* scatter back to global vector */ 68 PetscCall(VecScatterBegin(fromlocalall,localall,global,INSERT_VALUES,SCATTER_FORWARD)); 69 PetscCall(VecScatterEnd(fromlocalall,localall,global,INSERT_VALUES,SCATTER_FORWARD)); 70 71 PetscCall(VecView(global,viewer)); 72 73 /* Free memory */ 74 PetscCall(VecScatterDestroy(&tolocalall)); 75 PetscCall(VecScatterDestroy(&fromlocalall)); 76 PetscCall(PetscViewerDestroy(&viewer)); 77 PetscCall(VecDestroy(&localall)); 78 PetscCall(VecDestroy(&global)); 79 PetscCall(DMDestroy(&da)); 80 PetscCall(PetscFinalize()); 81 return 0; 82 } 83 84 /*TEST 85 86 build: 87 requires: !complex 88 89 test: 90 nsize: 3 91 92 TEST*/ 93