Actual source code: ex3.c
petsc-3.12.1 2019-10-22
2: static char help[] = "Tests parallel vector assembly. Input arguments are\n\
3: -n <length> : local vector length\n\n";
5: #include <petscvec.h>
7: int main(int argc,char **argv)
8: {
9: PetscMPIInt size,rank;
11: PetscInt n = 5,idx;
12: PetscScalar one = 1.0,two = 2.0,three = 3.0;
13: Vec x,y;
15: PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
16: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
17: if (n < 5) n = 5;
18: MPI_Comm_size(PETSC_COMM_WORLD,&size);
19: MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
21: if (size < 2) SETERRQ(PETSC_COMM_SELF,1,"Must be run with at least two processors");
23: /* create two vector */
24: VecCreateSeq(PETSC_COMM_SELF,n,&x);
25: VecCreate(PETSC_COMM_WORLD,&y);
26: VecSetSizes(y,n,PETSC_DECIDE);
27: VecSetFromOptions(y);
28: VecSet(x,one);
29: VecSet(y,two);
31: if (rank == 1) {
32: idx = 2; VecSetValues(y,1,&idx,&three,INSERT_VALUES);
33: idx = 0; VecSetValues(y,1,&idx,&two,INSERT_VALUES);
34: idx = 0; VecSetValues(y,1,&idx,&one,INSERT_VALUES);
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 ierr;
48: }
50: /*TEST
52: test:
53: nsize: 2
55: test:
56: suffix: 2
57: nsize: 2
58: args: -vec_view ascii::ascii_info
60: TEST*/