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: {
 11:   int         n,ierr,rank,size,*ispetsc,*isapp,start,N,i;
 12:   AO          ao;

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

 19:   /* create the orderings */
 20:   PetscMalloc(2*n*sizeof(int),&ispetsc);
 21:   isapp   = ispetsc + n;

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

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

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

 35:   AOView(ao,PETSC_VIEWER_STDOUT_WORLD);

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

 45:   PetscFree(ispetsc);

 47:   AODestroy(ao);
 48:   PetscFinalize();
 49:   return 0;
 50: }
 51: