Map distribution over MPI processes

[paganol]

It would be nice to have a function that reads maps (or generates maps with MBS) and spreads it over all the MPI processes.

[mreineck]

Are you thinking about an approach like this (pseudocode!)?

def generate_and_broadcast(generator, comm):
    result = generator() if comm.rank == 0 else None
    return comm.bcast(result)

generator can be a lambda or a function that either loads maps from disk or computes them on the fly.

[paganol]

Hi @mreineck, as first implementation, yes I was thinking to something like that. Than, probably, we should write something more refined for broadcasting properly maps, alms or other quantities based on the detector distribution across the mpi tasks.

[paganol]

I think this is addressed by #334, right?

[ziotom78]

I think this is addressed by #334, right?

#334 addresses the distribution of detectors, so if MBS generates maps according to which detectors are available on an MPI node, then yes, that PR addresses this issue.