Actual source code: ex2.c

  1: /*$Id: ex2.c,v 1.21 2001/04/10 19:37:18 bsmith Exp $*/

  3: static char help[] = "Tests application ordering.nn";

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

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

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

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

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

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

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

 34:   AOView(ao,PETSC_VIEWER_STDOUT_WORLD);

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

 44:   PetscFree(ispetsc);

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