xref: /petsc/src/vec/is/is/tests/ex5.c (revision 1e1ea65d8de51fde77ce8a787efbef25e407badc)
1 
2 static char help[] = "Tests ISLocalToGlobalMappingGetInfo.()\n\n";
3 
4 #include <petscis.h>
5 
6 int main(int argc,char **argv)
7 {
8   PetscErrorCode         ierr;
9   PetscMPIInt            size,rank;
10   PetscInt               nlocal,local[5],nneigh,*neigh,**ineigh,*numneigh;
11   ISLocalToGlobalMapping mapping;
12 
13   ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
14   ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRMPI(ierr);
15   if (size != 3) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_WRONG_MPI_SIZE,"Must run with three processors");
16   ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRMPI(ierr);
17   if (!rank) {
18     nlocal = 4; local[0] = 0; local[1] = 3; local[2] = 2; local[3] = 1;
19   } else if (rank == 1) {
20     nlocal = 4; local[0] = 3; local[1] = 5; local[2] = 4; local[3] = 2;
21   } else {
22     nlocal = 4; local[0] = 7; local[1] = 6; local[2] = 5; local[3] = 3;
23   }
24   ierr = ISLocalToGlobalMappingCreate(PETSC_COMM_WORLD,1,nlocal,local,PETSC_COPY_VALUES,&mapping);CHKERRQ(ierr);
25   ierr = ISLocalToGlobalMappingGetInfo(mapping,&nneigh,&neigh,&numneigh,&ineigh);CHKERRQ(ierr);
26   ierr = ISLocalToGlobalMappingRestoreInfo(mapping,&nneigh,&neigh,&numneigh,&ineigh);CHKERRQ(ierr);
27   ierr = ISLocalToGlobalMappingDestroy(&mapping);CHKERRQ(ierr);
28   ierr = PetscFinalize();
29   return ierr;
30 }
31 
32 /*TEST
33 
34    test:
35       nsize: 3
36       output_file: output/ex1_1.out
37 
38 TEST*/
39