static PetscErrorCode VecSetUp_NestIS_Private(Vec V,PetscInt nb,IS is[])
{
Vec_Nest *ctx = (Vec_Nest*)V->data;
PetscInt i,offset,m,n,M,N;
PetscErrorCode ierr;
PetscFunctionBegin;
if (is) { /* Do some consistency checks and reference the is */
offset = V->map->rstart;
for (i=0; i<ctx->nb; i++) {
ierr = ISGetSize(is[i],&M);CHKERRQ(ierr);
ierr = VecGetSize(ctx->v[i],&N);CHKERRQ(ierr);
if (M != N) SETERRQ3(PetscObjectComm((PetscObject)V),PETSC_ERR_ARG_INCOMP,"In slot %D, IS of size %D is not compatible with Vec of size %D",i,M,N);
ierr = ISGetLocalSize(is[i],&m);CHKERRQ(ierr);
ierr = VecGetLocalSize(ctx->v[i],&n);CHKERRQ(ierr);
if (m != n) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"In slot %D, IS of local size %D is not compatible with Vec of local size %D",i,m,n);
#if defined(PETSC_USE_DEBUG)
{ /* This test can be expensive */
PetscInt start;
PetscBool contiguous;
ierr = ISContiguousLocal(is[i],offset,offset+n,&start,&contiguous);CHKERRQ(ierr);
if (!contiguous) SETERRQ1(PetscObjectComm((PetscObject)V),PETSC_ERR_SUP,"Index set %D is not contiguous with layout of matching vector",i);
if (start != 0) SETERRQ1(PetscObjectComm((PetscObject)V),PETSC_ERR_SUP,"Index set %D introduces overlap or a hole",i);
}
#endif
ierr = PetscObjectReference((PetscObject)is[i]);CHKERRQ(ierr);
ctx->is[i] = is[i];
offset += n;
}
} else { /* Create a contiguous ISStride for each entry */
offset = V->map->rstart;
for (i=0; i<ctx->nb; i++) {
PetscInt bs;
ierr = VecGetLocalSize(ctx->v[i],&n);CHKERRQ(ierr);
ierr = VecGetBlockSize(ctx->v[i],&bs);CHKERRQ(ierr);
ierr = ISCreateStride(((PetscObject)ctx->v[i])->comm,n,offset,1,&ctx->is[i]);CHKERRQ(ierr);
ierr = ISSetBlockSize(ctx->is[i],bs);CHKERRQ(ierr);
offset += n;
}
}
PetscFunctionReturn(0);
}
void PETSC_STDCALL iscontiguouslocal_(IS is,PetscInt *gstart,PetscInt *gend,PetscInt *start,PetscBool *contig, int *__ierr ){
*__ierr = ISContiguousLocal(
(IS)PetscToPointer((is) ),*gstart,*gend,start,contig);
}
