1 2 static char help[] = "Demonstrates a scatter with a stride and general index set.\n\n"; 3 4 #include <petscvec.h> 5 6 int main(int argc,char **argv) 7 { 8 PetscInt n = 6,idx1[3] = {0,1,2},loc[6] = {0,1,2,3,4,5}; 9 PetscScalar two = 2.0,vals[6] = {10,11,12,13,14,15}; 10 Vec x,y; 11 IS is1,is2; 12 VecScatter ctx = 0; 13 14 PetscFunctionBeginUser; 15 PetscCall(PetscInitialize(&argc,&argv,(char*)0,help)); 16 17 /* create two vectors */ 18 PetscCall(VecCreateSeq(PETSC_COMM_SELF,n,&x)); 19 PetscCall(VecDuplicate(x,&y)); 20 21 /* create two index sets */ 22 PetscCall(ISCreateStride(PETSC_COMM_SELF,3,0,2,&is1)); 23 PetscCall(ISCreateGeneral(PETSC_COMM_SELF,3,idx1,PETSC_COPY_VALUES,&is2)); 24 25 PetscCall(VecSetValues(x,6,loc,vals,INSERT_VALUES)); 26 PetscCall(VecView(x,PETSC_VIEWER_STDOUT_SELF)); 27 PetscCall(PetscPrintf(PETSC_COMM_SELF,"----\n")); 28 PetscCall(VecSet(y,two)); 29 PetscCall(VecScatterCreate(x,is1,y,is2,&ctx)); 30 PetscCall(VecScatterBegin(ctx,x,y,INSERT_VALUES,SCATTER_FORWARD)); 31 PetscCall(VecScatterEnd(ctx,x,y,INSERT_VALUES,SCATTER_FORWARD)); 32 PetscCall(VecScatterDestroy(&ctx)); 33 34 PetscCall(VecView(y,PETSC_VIEWER_STDOUT_SELF)); 35 36 PetscCall(ISDestroy(&is1)); 37 PetscCall(ISDestroy(&is2)); 38 PetscCall(VecDestroy(&x)); 39 PetscCall(VecDestroy(&y)); 40 41 PetscCall(PetscFinalize()); 42 return 0; 43 } 44 45 /*TEST 46 47 test: 48 49 TEST*/ 50