Actual source code: ex18.c
2: /* np = 1 */
4: static char help[] = "Compares BLAS dots on different machines. Input\n\
5: arguments are\n\
6: -n <length> : local vector length\n\n";
8: #include petscvec.h
12: int main(int argc,char **argv)
13: {
15: PetscInt n = 15,i;
16: PetscScalar v;
17: Vec x,y;
19: PetscInitialize(&argc,&argv,(char*)0,help);
20: PetscOptionsGetInt(PETSC_NULL,"-n",&n,PETSC_NULL);
21: if (n < 5) n = 5;
24: /* create two vectors */
25: VecCreateSeq(PETSC_COMM_SELF,n,&x);
26: VecCreateSeq(PETSC_COMM_SELF,n,&y);
28: for (i=0; i<n; i++) {
29: v = ((PetscReal)i) + 1.0/(((PetscReal)i) + .35);
30: VecSetValues(x,1,&i,&v,INSERT_VALUES);
31: v += 1.375547826473644376;
32: VecSetValues(y,1,&i,&v,INSERT_VALUES);
33: }
34: VecAssemblyBegin(y);
35: VecAssemblyEnd(y);
37: VecDot(x,y,&v);
38: PetscFPrintf(PETSC_COMM_WORLD,stdout,"Vector inner product %16.12e\n",v);
40: VecDestroy(x);
41: VecDestroy(y);
43: PetscFinalize();
44: return 0;
45: }
46: