1 2 static char help[] = "Scatters from a parallel vector to a sequential vector.\n\ 3 Tests where the local part of the scatter is a copy.\n\n"; 4 5 #include <petscvec.h> 6 7 int main(int argc,char **argv) 8 { 9 PetscErrorCode ierr; 10 PetscMPIInt size,rank; 11 PetscInt n = 5,i,*blks,bs = 1,m = 2; 12 PetscScalar value; 13 Vec x,y; 14 IS is1,is2; 15 VecScatter ctx = 0; 16 PetscViewer sviewer; 17 18 ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr; 19 20 ierr = PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);CHKERRQ(ierr); 21 ierr = PetscOptionsGetInt(NULL,NULL,"-bs",&bs,NULL);CHKERRQ(ierr); 22 23 ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRMPI(ierr); 24 ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRMPI(ierr); 25 26 /* create two vectors */ 27 ierr = VecCreate(PETSC_COMM_WORLD,&x);CHKERRQ(ierr); 28 ierr = VecSetSizes(x,PETSC_DECIDE,size*bs*n);CHKERRQ(ierr); 29 ierr = VecSetFromOptions(x);CHKERRQ(ierr); 30 31 /* create two index sets */ 32 if (rank < size-1) m = n + 2; 33 else m = n; 34 35 ierr = PetscMalloc1(m,&blks);CHKERRQ(ierr); 36 blks[0] = n*rank; 37 for (i=1; i<m; i++) blks[i] = blks[i-1] + 1; 38 ierr = ISCreateBlock(PETSC_COMM_SELF,bs,m,blks,PETSC_COPY_VALUES,&is1);CHKERRQ(ierr); 39 ierr = PetscFree(blks);CHKERRQ(ierr); 40 41 ierr = VecCreateSeq(PETSC_COMM_SELF,bs*m,&y);CHKERRQ(ierr); 42 ierr = ISCreateStride(PETSC_COMM_SELF,bs*m,0,1,&is2);CHKERRQ(ierr); 43 44 /* each processor inserts the entire vector */ 45 /* this is redundant but tests assembly */ 46 for (i=0; i<bs*n*size; i++) { 47 value = (PetscScalar) i; 48 ierr = VecSetValues(x,1,&i,&value,INSERT_VALUES);CHKERRQ(ierr); 49 } 50 ierr = VecAssemblyBegin(x);CHKERRQ(ierr); 51 ierr = VecAssemblyEnd(x);CHKERRQ(ierr); 52 ierr = VecView(x,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 53 54 ierr = VecScatterCreate(x,is1,y,is2,&ctx);CHKERRQ(ierr); 55 ierr = VecScatterBegin(ctx,x,y,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 56 ierr = VecScatterEnd(ctx,x,y,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 57 58 ierr = PetscViewerASCIIPushSynchronized(PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 59 ierr = PetscViewerASCIISynchronizedPrintf(PETSC_VIEWER_STDOUT_WORLD,"----\n");CHKERRQ(ierr); 60 ierr = PetscViewerGetSubViewer(PETSC_VIEWER_STDOUT_WORLD,PETSC_COMM_SELF,&sviewer);CHKERRQ(ierr); 61 ierr = VecView(y,sviewer);CHKERRQ(ierr); fflush(stdout); 62 ierr = PetscViewerRestoreSubViewer(PETSC_VIEWER_STDOUT_WORLD,PETSC_COMM_SELF,&sviewer);CHKERRQ(ierr); 63 ierr = PetscViewerFlush(PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 64 ierr = PetscViewerASCIIPopSynchronized(PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 65 66 ierr = VecScatterDestroy(&ctx);CHKERRQ(ierr); 67 68 ierr = VecDestroy(&x);CHKERRQ(ierr); 69 ierr = VecDestroy(&y);CHKERRQ(ierr); 70 ierr = ISDestroy(&is1);CHKERRQ(ierr); 71 ierr = ISDestroy(&is2);CHKERRQ(ierr); 72 73 ierr = PetscFinalize(); 74 return ierr; 75 } 76 77 78 79 /*TEST 80 81 testset: 82 nsize: 3 83 output_file: output/ex24_1.out 84 filter: grep -v " type:" 85 test: 86 suffix: standard 87 args: -vec_type standard 88 test: 89 requires: cuda 90 suffix: cuda 91 args: -vec_type cuda 92 test: 93 requires: viennacl 94 suffix: viennacl 95 args: -vec_type viennacl 96 97 TEST*/ 98