static PetscErrorCode DMCreateInterpolation_Redundant(DM dmc,DM dmf,Mat *P,Vec *scale)
{
PetscErrorCode ierr;
DM_Redundant *redc = (DM_Redundant*)dmc->data;
DM_Redundant *redf = (DM_Redundant*)dmf->data;
PetscMPIInt flag;
PetscInt i,rstart,rend;
PetscFunctionBegin;
ierr = MPI_Comm_compare(PetscObjectComm((PetscObject)dmc),PetscObjectComm((PetscObject)dmf),&flag);CHKERRQ(ierr);
if (flag != MPI_CONGRUENT && flag != MPI_IDENT) SETERRQ(PetscObjectComm((PetscObject)dmf),PETSC_ERR_SUP,"cannot change communicators");
if (redc->rank != redf->rank) SETERRQ(PetscObjectComm((PetscObject)dmf),PETSC_ERR_ARG_INCOMP,"Owning rank does not match");
if (redc->N != redf->N) SETERRQ(PetscObjectComm((PetscObject)dmf),PETSC_ERR_ARG_INCOMP,"Global size does not match");
ierr = MatCreate(PetscObjectComm((PetscObject)dmc),P);CHKERRQ(ierr);
ierr = MatSetSizes(*P,redc->n,redc->n,redc->N,redc->N);CHKERRQ(ierr);
ierr = MatSetType(*P,MATAIJ);CHKERRQ(ierr);
ierr = MatSeqAIJSetPreallocation(*P,1,0);CHKERRQ(ierr);
ierr = MatMPIAIJSetPreallocation(*P,1,0,0,0);CHKERRQ(ierr);
ierr = MatGetOwnershipRange(*P,&rstart,&rend);CHKERRQ(ierr);
for (i=rstart; i<rend; i++) {ierr = MatSetValue(*P,i,i,1.0,INSERT_VALUES);CHKERRQ(ierr);}
ierr = MatAssemblyBegin(*P,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatAssemblyEnd(*P,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
if (scale) {ierr = DMCreateInterpolationScale(dmc,dmf,*P,scale);CHKERRQ(ierr);}
PetscFunctionReturn(0);
}
PETSC_EXTERN void PETSC_STDCALL dmcreateinterpolationscale_(DM dac,DM daf,Mat mat,Vec *scale, int *__ierr ){
*__ierr = DMCreateInterpolationScale(
(DM)PetscToPointer((dac) ),
(DM)PetscToPointer((daf) ),
(Mat)PetscToPointer((mat) ),scale);
}
