1 2 static char help[] = "Scatters between parallel vectors. \n\ 3 uses block index sets\n\n"; 4 5 #include <petscvec.h> 6 7 int main(int argc, char **argv) 8 { 9 PetscInt bs = 1, n = 5, N, i, low; 10 PetscInt ix0[3] = {5, 7, 9}, iy0[3] = {1, 2, 4}, ix1[3] = {2, 3, 1}, iy1[3] = {0, 3, 9}; 11 PetscMPIInt size, rank; 12 PetscScalar *array; 13 Vec x, x1, y; 14 IS isx, isy; 15 VecScatter ctx; 16 VecScatterType type; 17 PetscBool flg; 18 19 PetscFunctionBeginUser; 20 PetscCall(PetscInitialize(&argc, &argv, (char *)0, help)); 21 PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size)); 22 PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank)); 23 24 PetscCheck(size >= 2, PETSC_COMM_WORLD, PETSC_ERR_WRONG_MPI_SIZE, "Must run more than one processor"); 25 26 PetscCall(PetscOptionsGetInt(NULL, NULL, "-bs", &bs, NULL)); 27 n = bs * n; 28 29 /* Create vector x over shared memory */ 30 PetscCall(VecCreate(PETSC_COMM_WORLD, &x)); 31 PetscCall(VecSetSizes(x, n, PETSC_DECIDE)); 32 PetscCall(VecSetFromOptions(x)); 33 34 PetscCall(VecGetOwnershipRange(x, &low, NULL)); 35 PetscCall(VecGetArray(x, &array)); 36 for (i = 0; i < n; i++) array[i] = (PetscScalar)(i + low); 37 PetscCall(VecRestoreArray(x, &array)); 38 /* PetscCall(VecView(x,PETSC_VIEWER_STDOUT_WORLD)); */ 39 40 /* Test some vector functions */ 41 PetscCall(VecAssemblyBegin(x)); 42 PetscCall(VecAssemblyEnd(x)); 43 44 PetscCall(VecGetSize(x, &N)); 45 PetscCall(VecGetLocalSize(x, &n)); 46 47 PetscCall(VecDuplicate(x, &x1)); 48 PetscCall(VecCopy(x, x1)); 49 PetscCall(VecEqual(x, x1, &flg)); 50 PetscCheck(flg, PetscObjectComm((PetscObject)x), PETSC_ERR_ARG_WRONG, "x1 != x"); 51 52 PetscCall(VecScale(x1, 2.0)); 53 PetscCall(VecSet(x1, 10.0)); 54 /* PetscCall(VecView(x1,PETSC_VIEWER_STDOUT_WORLD)); */ 55 56 /* Create vector y over shared memory */ 57 PetscCall(VecCreate(PETSC_COMM_WORLD, &y)); 58 PetscCall(VecSetSizes(y, n, PETSC_DECIDE)); 59 PetscCall(VecSetFromOptions(y)); 60 PetscCall(VecGetArray(y, &array)); 61 for (i = 0; i < n; i++) array[i] = -(PetscScalar)(i + 100 * rank); 62 PetscCall(VecRestoreArray(y, &array)); 63 PetscCall(VecAssemblyBegin(y)); 64 PetscCall(VecAssemblyEnd(y)); 65 /* PetscCall(VecView(y,PETSC_VIEWER_STDOUT_WORLD)); */ 66 67 /* Create two index sets */ 68 if (rank == 0) { 69 PetscCall(ISCreateBlock(PETSC_COMM_SELF, bs, 3, ix0, PETSC_COPY_VALUES, &isx)); 70 PetscCall(ISCreateBlock(PETSC_COMM_SELF, bs, 3, iy0, PETSC_COPY_VALUES, &isy)); 71 } else { 72 PetscCall(ISCreateBlock(PETSC_COMM_SELF, bs, 3, ix1, PETSC_COPY_VALUES, &isx)); 73 PetscCall(ISCreateBlock(PETSC_COMM_SELF, bs, 3, iy1, PETSC_COPY_VALUES, &isy)); 74 } 75 76 if (rank == 10) { 77 PetscCall(PetscPrintf(PETSC_COMM_SELF, "\n[%d] isx:\n", rank)); 78 PetscCall(ISView(isx, PETSC_VIEWER_STDOUT_SELF)); 79 PetscCall(PetscPrintf(PETSC_COMM_SELF, "\n[%d] isy:\n", rank)); 80 PetscCall(ISView(isy, PETSC_VIEWER_STDOUT_SELF)); 81 } 82 83 /* Create Vector scatter */ 84 PetscCall(VecScatterCreate(x, isx, y, isy, &ctx)); 85 PetscCall(VecScatterSetFromOptions(ctx)); 86 PetscCall(VecScatterGetType(ctx, &type)); 87 PetscCall(PetscPrintf(PETSC_COMM_WORLD, "scatter type %s\n", type)); 88 89 /* Test forward vecscatter */ 90 PetscCall(VecSet(y, 0.0)); 91 PetscCall(VecScatterBegin(ctx, x, y, ADD_VALUES, SCATTER_FORWARD)); 92 PetscCall(VecScatterEnd(ctx, x, y, ADD_VALUES, SCATTER_FORWARD)); 93 PetscCall(PetscPrintf(PETSC_COMM_WORLD, "\nSCATTER_FORWARD y:\n")); 94 PetscCall(VecView(y, PETSC_VIEWER_STDOUT_WORLD)); 95 96 /* Test reverse vecscatter */ 97 PetscCall(VecSet(x, 0.0)); 98 PetscCall(VecSet(y, 0.0)); 99 PetscCall(VecGetOwnershipRange(y, &low, NULL)); 100 PetscCall(VecGetArray(y, &array)); 101 for (i = 0; i < n; i++) array[i] = (PetscScalar)(i + low); 102 PetscCall(VecRestoreArray(y, &array)); 103 PetscCall(VecScatterBegin(ctx, y, x, ADD_VALUES, SCATTER_REVERSE)); 104 PetscCall(VecScatterEnd(ctx, y, x, ADD_VALUES, SCATTER_REVERSE)); 105 PetscCall(PetscPrintf(PETSC_COMM_WORLD, "\nSCATTER_REVERSE x:\n")); 106 PetscCall(VecView(x, PETSC_VIEWER_STDOUT_WORLD)); 107 108 /* Free objects */ 109 PetscCall(VecScatterDestroy(&ctx)); 110 PetscCall(ISDestroy(&isx)); 111 PetscCall(ISDestroy(&isy)); 112 PetscCall(VecDestroy(&x)); 113 PetscCall(VecDestroy(&x1)); 114 PetscCall(VecDestroy(&y)); 115 PetscCall(PetscFinalize()); 116 return 0; 117 } 118 119 /*TEST 120 121 test: 122 nsize: 2 123 124 TEST*/ 125