Actual source code: ex2.c


  2: static char help[] = "Tests application ordering.\n\n";

  4: #include <petscsys.h>
  5: #include <petscao.h>
  6: #include <petscviewer.h>

  8: int main(int argc, char **argv)
  9: {
 10:   PetscMPIInt rank, size;
 11:   PetscInt    n, *ispetsc, *isapp, start, N, i;
 12:   AO          ao;

 14:   PetscFunctionBeginUser;
 15:   PetscCall(PetscInitialize(&argc, &argv, (char *)0, help));
 16:   PetscCall(PetscOptionsGetInt(NULL, NULL, "-n", &n, NULL));
 17:   PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
 18:   n = rank + 2;
 19:   PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));

 21:   /* create the orderings */
 22:   PetscCall(PetscMalloc2(n, &ispetsc, n, &isapp));

 24:   PetscCallMPI(MPI_Scan(&n, &start, 1, MPIU_INT, MPI_SUM, PETSC_COMM_WORLD));
 25:   PetscCall(MPIU_Allreduce(&n, &N, 1, MPIU_INT, MPI_SUM, PETSC_COMM_WORLD));
 26:   start -= n;

 28:   for (i = 0; i < n; i++) {
 29:     ispetsc[i] = start + i;
 30:     isapp[i]   = N - start - i - 1;
 31:   }

 33:   /* create the application ordering */
 34:   PetscCall(AOCreateBasic(PETSC_COMM_WORLD, n, isapp, ispetsc, &ao));
 35:   PetscCall(AOView(ao, PETSC_VIEWER_STDOUT_WORLD));

 37:   /* check the mapping */
 38:   PetscCall(AOPetscToApplication(ao, n, ispetsc));
 39:   for (i = 0; i < n; i++) {
 40:     if (ispetsc[i] != isapp[i]) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "[%d] Problem with mapping %" PetscInt_FMT " to %" PetscInt_FMT "\n", rank, i, ispetsc[i]));
 41:   }
 42:   PetscCall(PetscFree2(ispetsc, isapp));

 44:   PetscCall(AODestroy(&ao));
 45:   PetscCall(PetscFinalize());
 46:   return 0;
 47: }

 49: /*TEST

 51:    test:

 53:    test:
 54:       suffix: 2
 55:       nsize: 2

 57:    test:
 58:       suffix: 3
 59:       nsize: 3

 61: TEST*/