Adrian Croucher <[email protected]> writes: > On 12/3/21 12:09 PM, Jed Brown wrote: >> Many find MPI_Comm_split() to be a more convenient interface. > Yes, I don't think that will work for my case though, as my groups may > overlap, and some processes may not be in any group.
You'd need more calls in case of overlap (so MPI_Comm_create_group is more natural), but non-participating ranks is easy. | A process may supply the color value MPI_UNDEFINED, in which case newcomm returns MPI_COMM_NULL.
