Thanks, Barry, Satish, But, is it possible to uniform the use of MPI_SUM and MPIU_SUM? For example, we could let a Petsc function just switch to a regular MPI_Reduce or other function when using PetscInt. In other words, we need a wrapper. I always use MPIU_INT in a MPI function when using PetscInt. It is very straightforward to use MPIU_SUM, MPIU_MAX so on, when thinking about we are using MPIU_INT.
Thanks, Fande Kong, On Mon, Aug 17, 2015 at 6:18 PM, Barry Smith <[email protected]> wrote: > > It is crucial. MPI also doesn't provide sums for __float128 precision. > But MPI does always provide sums for 32 and 64 bit integers so no need for > MPIU_SUM for PETSC_INT > > > > On Aug 17, 2015, at 5:49 PM, Satish Balay <[email protected]> wrote: > > > > I think some MPI impls didn't provide some of the ops on MPI_COMPLEX > > datatype. > > > > So petsc provides these ops for PetscReal i.e MPIU_SUM, MPIU_MAX, > MPIU_MIN > > > > Satish > > > > On Mon, 17 Aug 2015, Fande Kong wrote: > > > >> Hi all, > >> > >> I was wondering why, in Petsc, MPI_Reduce with PetscInt needs MPI_SUM > >> meanwhile MPI_Reduce with PetscReal needs MPIU_SUM? Do we have any > special > >> reasons to distinguish them? > >> > >> Thanks, > >> > >> Fande Kong, > >> > > > >
