1 2 static char help[] = "Tests DMDAGlobalToNaturalAllCreate() using contour plotting for 2d DMDAs.\n\n"; 3 4 5 #include <petscdm.h> 6 #include <petscdmda.h> 7 #include <petscdraw.h> 8 9 int main(int argc,char **argv) 10 { 11 PetscInt i,j,M = 10,N = 8,m = PETSC_DECIDE,n = PETSC_DECIDE; 12 PetscMPIInt rank; 13 PetscErrorCode ierr; 14 PetscBool flg = PETSC_FALSE; 15 DM da; 16 PetscViewer viewer; 17 Vec localall,global; 18 PetscScalar value,*vlocal; 19 DMBoundaryType bx = DM_BOUNDARY_NONE,by = DM_BOUNDARY_NONE; 20 DMDAStencilType stype = DMDA_STENCIL_BOX; 21 VecScatter tolocalall,fromlocalall; 22 PetscInt start,end; 23 24 ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr; 25 ierr = PetscViewerDrawOpen(PETSC_COMM_WORLD,0,"",300,0,300,300,&viewer);CHKERRQ(ierr); 26 27 /* Read options */ 28 ierr = PetscOptionsGetInt(NULL,NULL,"-M",&M,NULL);CHKERRQ(ierr); 29 ierr = PetscOptionsGetInt(NULL,NULL,"-N",&N,NULL);CHKERRQ(ierr); 30 ierr = PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL);CHKERRQ(ierr); 31 ierr = PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);CHKERRQ(ierr); 32 ierr = PetscOptionsGetBool(NULL,NULL,"-star_stencil",&flg,NULL);CHKERRQ(ierr); 33 if (flg) stype = DMDA_STENCIL_STAR; 34 35 /* Create distributed array and get vectors */ 36 ierr = DMDACreate2d(PETSC_COMM_WORLD,bx,by,stype,M,N,m,n,1,1,NULL,NULL,&da);CHKERRQ(ierr); 37 ierr = DMSetFromOptions(da);CHKERRQ(ierr); 38 ierr = DMSetUp(da);CHKERRQ(ierr); 39 40 ierr = DMCreateGlobalVector(da,&global);CHKERRQ(ierr); 41 ierr = VecCreateSeq(PETSC_COMM_SELF,M*N,&localall);CHKERRQ(ierr); 42 43 ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr); 44 ierr = VecGetOwnershipRange(global,&start,&end);CHKERRQ(ierr); 45 for (i=start; i<end; i++) { 46 value = 5.0*rank; 47 ierr = VecSetValues(global,1,&i,&value,INSERT_VALUES);CHKERRQ(ierr); 48 } 49 ierr = VecView(global,viewer);CHKERRQ(ierr); 50 51 /* 52 Create Scatter from global DMDA parallel vector to local vector that 53 contains all entries 54 */ 55 ierr = DMDAGlobalToNaturalAllCreate(da,&tolocalall);CHKERRQ(ierr); 56 ierr = DMDANaturalAllToGlobalCreate(da,&fromlocalall);CHKERRQ(ierr); 57 58 ierr = VecScatterBegin(tolocalall,global,localall,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 59 ierr = VecScatterEnd(tolocalall,global,localall,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 60 61 ierr = VecGetArray(localall,&vlocal);CHKERRQ(ierr); 62 for (j=0; j<N; j++) { 63 for (i=0; i<M; i++) { 64 *vlocal++ += i + j*M; 65 } 66 } 67 ierr = VecRestoreArray(localall,&vlocal);CHKERRQ(ierr); 68 69 /* scatter back to global vector */ 70 ierr = VecScatterBegin(fromlocalall,localall,global,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 71 ierr = VecScatterEnd(fromlocalall,localall,global,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 72 73 ierr = VecView(global,viewer);CHKERRQ(ierr); 74 75 /* Free memory */ 76 ierr = VecScatterDestroy(&tolocalall);CHKERRQ(ierr); 77 ierr = VecScatterDestroy(&fromlocalall);CHKERRQ(ierr); 78 ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr); 79 ierr = VecDestroy(&localall);CHKERRQ(ierr); 80 ierr = VecDestroy(&global);CHKERRQ(ierr); 81 ierr = DMDestroy(&da);CHKERRQ(ierr); 82 ierr = PetscFinalize(); 83 return ierr; 84 } 85 86 87 88 /*TEST 89 90 build: 91 requires: !complex 92 93 test: 94 nsize: 3 95 96 TEST*/ 97