/*
DMLocalToLocalCreate_DA - Creates the local to local scatter
Collective on DMDA
Input Parameter:
. da - the distributed array
*/
PetscErrorCode DMLocalToLocalCreate_DA(DM da)
{
PetscErrorCode ierr;
PetscInt *idx,left,j,count,up,down,i,bottom,top,k,dim=da->dim;
DM_DA *dd = (DM_DA*)da->data;
PetscFunctionBegin;
PetscValidHeaderSpecific(da,DM_CLASSID,1);
if (dd->ltol) PetscFunctionReturn(0);
/*
We simply remap the values in the from part of
global to local to read from an array with the ghost values
rather then from the plain array.
*/
ierr = VecScatterCopy(dd->gtol,&dd->ltol);CHKERRQ(ierr);
ierr = PetscLogObjectParent((PetscObject)da,(PetscObject)dd->ltol);CHKERRQ(ierr);
if (dim == 1) {
left = dd->xs - dd->Xs;
ierr = PetscMalloc1(dd->xe-dd->xs,&idx);CHKERRQ(ierr);
for (j=0; j<dd->xe-dd->xs; j++) idx[j] = left + j;
} else if (dim == 2) {
left = dd->xs - dd->Xs; down = dd->ys - dd->Ys; up = down + dd->ye-dd->ys;
ierr = PetscMalloc1((dd->xe-dd->xs)*(up - down),&idx);CHKERRQ(ierr);
count = 0;
for (i=down; i<up; i++) {
for (j=0; j<dd->xe-dd->xs; j++) {
idx[count++] = left + i*(dd->Xe-dd->Xs) + j;
}
}
} else if (dim == 3) {
left = dd->xs - dd->Xs;
bottom = dd->ys - dd->Ys; top = bottom + dd->ye-dd->ys;
down = dd->zs - dd->Zs; up = down + dd->ze-dd->zs;
count = (dd->xe-dd->xs)*(top-bottom)*(up-down);
ierr = PetscMalloc1(count,&idx);CHKERRQ(ierr);
count = 0;
for (i=down; i<up; i++) {
for (j=bottom; j<top; j++) {
for (k=0; k<dd->xe-dd->xs; k++) {
idx[count++] = (left+j*(dd->Xe-dd->Xs))+i*(dd->Xe-dd->Xs)*(dd->Ye-dd->Ys) + k;
}
}
}
} else SETERRQ1(PetscObjectComm((PetscObject)da),PETSC_ERR_ARG_CORRUPT,"DMDA has invalid dimension %D",dim);
ierr = VecScatterRemap(dd->ltol,idx,NULL);CHKERRQ(ierr);
ierr = PetscFree(idx);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
uses block index sets\n\n";
#include <petscvec.h>
#undef __FUNCT__
#define __FUNCT__ "main"
int main(int argc,char **argv)
{
PetscErrorCode ierr;
PetscInt bs = 1,n = 5,ix0[3] = {5,7,9},ix1[3] = {2,3,4},i,iy0[3] = {1,2,4},iy1[3] = {0,1,3};
PetscMPIInt size,rank;
PetscScalar value;
Vec x,y;
IS isx,isy;
VecScatter ctx = 0,newctx;
ierr = PetscInitialize(&argc,&argv,(char*)0,help);CHKERRQ(ierr);
ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRQ(ierr);
ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr);
if (size != 2) SETERRQ(PETSC_COMM_SELF,1,"Must run with 2 processors");
ierr = PetscOptionsGetInt(PETSC_NULL,"-bs",&bs,PETSC_NULL);CHKERRQ(ierr);
n = bs*n;
/* create two vectors */
ierr = VecCreate(PETSC_COMM_WORLD,&x);CHKERRQ(ierr);
ierr = VecSetSizes(x,PETSC_DECIDE,size*n);CHKERRQ(ierr);
ierr = VecSetFromOptions(x);CHKERRQ(ierr);
ierr = VecCreateSeq(PETSC_COMM_SELF,n,&y);CHKERRQ(ierr);
/* create two index sets */
if (!rank) {
ierr = ISCreateBlock(PETSC_COMM_SELF,bs,3,ix0,PETSC_COPY_VALUES,&isx);CHKERRQ(ierr);
ierr = ISCreateBlock(PETSC_COMM_SELF,bs,3,iy0,PETSC_COPY_VALUES,&isy);CHKERRQ(ierr);
} else {
ierr = ISCreateBlock(PETSC_COMM_SELF,bs,3,ix1,PETSC_COPY_VALUES,&isx);CHKERRQ(ierr);
ierr = ISCreateBlock(PETSC_COMM_SELF,bs,3,iy1,PETSC_COPY_VALUES,&isy);CHKERRQ(ierr);
}
/* fill local part of parallel vector */
for (i=n*rank; i<n*(rank+1); i++) {
value = (PetscScalar) i;
ierr = VecSetValues(x,1,&i,&value,INSERT_VALUES);CHKERRQ(ierr);
}
ierr = VecAssemblyBegin(x);CHKERRQ(ierr);
ierr = VecAssemblyEnd(x);CHKERRQ(ierr);
ierr = VecView(x,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
/* fill local part of parallel vector */
for (i=0; i<n; i++) {
value = -(PetscScalar) (i + 100*rank);
ierr = VecSetValues(y,1,&i,&value,INSERT_VALUES);CHKERRQ(ierr);
}
ierr = VecAssemblyBegin(y);CHKERRQ(ierr);
ierr = VecAssemblyEnd(y);CHKERRQ(ierr);
ierr = VecScatterCreate(x,isx,y,isy,&ctx);CHKERRQ(ierr);
ierr = VecScatterCopy(ctx,&newctx);CHKERRQ(ierr);
ierr = VecScatterDestroy(&ctx);CHKERRQ(ierr);
ierr = VecScatterBegin(newctx,y,x,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
ierr = VecScatterEnd(newctx,y,x,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
ierr = VecScatterDestroy(&newctx);CHKERRQ(ierr);
ierr = VecView(x,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
ierr = ISDestroy(&isx);CHKERRQ(ierr);
ierr = ISDestroy(&isy);CHKERRQ(ierr);
ierr = VecDestroy(&x);CHKERRQ(ierr);
ierr = VecDestroy(&y);CHKERRQ(ierr);
ierr = PetscFinalize();
return 0;
}
void PETSC_STDCALL vecscattercopy_(VecScatter sctx,VecScatter *ctx, int *__ierr ){
*__ierr = VecScatterCopy(
(VecScatter)PetscToPointer((sctx) ),ctx);
}
