Actual source code: ex2.c

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

 4:  #include petsc.h
 5:  #include petscao.h

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

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

 21:   /* create the orderings */
 22:   PetscMalloc(2*n*sizeof(PetscInt),&ispetsc);
 23:   isapp   = ispetsc + n;

 25:   MPI_Scan(&n,&start,1,MPI_INT,MPI_SUM,PETSC_COMM_WORLD);
 26:   MPI_Allreduce(&n,&N,1,MPI_INT,MPI_SUM,PETSC_COMM_WORLD);
 27:   start -= n;

 29:   for (i=0; i<n; i++) {
 30:     ispetsc[i] = start + i;
 31:     isapp[i]   = N - start - i - 1;
 32:   }

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

 37:   AOView(ao,PETSC_VIEWER_STDOUT_WORLD);

 39:   /* check the mapping */
 40:   AOPetscToApplication(ao,n,ispetsc);
 41:   for (i=0; i<n; i++) {
 42:     if (ispetsc[i] != isapp[i]) {
 43:       fprintf(stdout,"[%d] Problem with mapping %d to %d\n",rank,(int)i,(int)ispetsc[i]);
 44:     }
 45:   }

 47:   PetscFree(ispetsc);

 49:   AODestroy(ao);
 50:   PetscFinalize();
 51:   return 0;
 52: }
 53: