Merged requested to merge correct_MPI_reduce into master
I was looking at the implementation of a reduce operation over MPI for the multipoles and I stumbled upon this.
If my reading of section 5.9.5 of the MPI standard is correct then I think we need a loop over both the vectors passed into this function and not just the
in one. Since we are doing a reduce of
len 1 here, it likely makes no difference I'd better be safe here and use the recommended signature. What do you think?