Actual source code: ex7.c
  1: static char help[] = "Demonstrates constructing an application ordering.\n\n";
  3: #include <petscao.h>
  4: #include <petscviewer.h>
  6: int main(int argc, char **argv)
  7: {
  8:   PetscInt    n = 5;
  9:   PetscMPIInt rank, size;
 10:   IS          ispetsc, isapp;
 11:   AO          ao;
 13:   PetscFunctionBeginUser;
 14:   PetscCall(PetscInitialize(&argc, &argv, NULL, help));
 15:   PetscCall(PetscOptionsGetInt(NULL, NULL, "-n", &n, NULL));
 16:   PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
 17:   PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
 19:   /* create the index sets */
 20:   PetscCall(ISCreateStride(PETSC_COMM_WORLD, n, rank, size, &ispetsc));
 21:   PetscCall(ISCreateStride(PETSC_COMM_WORLD, n, n * rank, 1, &isapp));
 23:   /* create the application ordering */
 24:   PetscCall(AOCreateBasicIS(isapp, ispetsc, &ao));
 26:   PetscCall(AOView(ao, PETSC_VIEWER_STDOUT_WORLD));
 28:   PetscCall(ISView(ispetsc, PETSC_VIEWER_STDOUT_WORLD));
 29:   PetscCall(ISView(isapp, PETSC_VIEWER_STDOUT_WORLD));
 30:   PetscCall(AOPetscToApplicationIS(ao, ispetsc));
 31:   PetscCall(ISView(isapp, PETSC_VIEWER_STDOUT_WORLD));
 32:   PetscCall(ISView(ispetsc, PETSC_VIEWER_STDOUT_WORLD));
 34:   PetscCall(ISDestroy(&ispetsc));
 35:   PetscCall(ISDestroy(&isapp));
 37:   PetscCall(AODestroy(&ao));
 38:   PetscCall(PetscFinalize());
 39:   return 0;
 40: }
 42: /*TEST
 44:    test:
 45:       nsize: 2
 47: TEST*/