Actual source code: ex3.c
1: /*$Id: ex3.c,v 1.52 2001/03/23 23:21:30 balay Exp $*/
3: static char help[] = "Tests parallel vector assembly. Input arguments aren
4: -n <length> : local vector lengthnn";
6: #include "petscvec.h"
7: #include "petscsys.h"
9: int main(int argc,char **argv)
10: {
11: int n = 5,ierr,size,rank;
12: Scalar one = 1.0,two = 2.0,three = 3.0;
13: Vec x,y;
14: int idx;
16: PetscInitialize(&argc,&argv,(char*)0,help);
17: PetscOptionsGetInt(PETSC_NULL,"-n",&n,PETSC_NULL);
18: if (n < 5) n = 5;
19: MPI_Comm_size(PETSC_COMM_WORLD,&size);
20: MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
22: if (size < 2) SETERRQ(1,"Must be run with at least two processors");
24: /* create two vector */
25: VecCreateSeq(PETSC_COMM_SELF,n,&x);
26: VecCreateMPI(PETSC_COMM_WORLD,n,PETSC_DECIDE,&y);
27: VecSet(&one,x);
28: VecSet(&two,y);
30: if (rank == 1) {
31: idx = 2; VecSetValues(y,1,&idx,&three,INSERT_VALUES);
32: idx = 0; VecSetValues(y,1,&idx,&two,INSERT_VALUES);
33: idx = 0; VecSetValues(y,1,&idx,&one,INSERT_VALUES);
34: }
35: else {
36: idx = 7; VecSetValues(y,1,&idx,&three,INSERT_VALUES);
37: }
38: VecAssemblyBegin(y);
39: VecAssemblyEnd(y);
41: VecView(y,PETSC_VIEWER_STDOUT_WORLD);
43: VecDestroy(x);
44: VecDestroy(y);
46: PetscFinalize();
47: return 0;
48: }
49: