[yt-dev] .quantities issue

[Stephen Skory]

Hi all,

when I was trying to work on Mike's latest halo finder problem, I
tried swapping out the total_mass sum for a .quantities on this line:

https://bitbucket.org/yt_analysis/yt/src/73fa0ace10e3/yt/analysis_modules/halo_finding/halo_objects.py#cl-2047

but doing that seriously changed the answers. Digging a bit deeper I
see that for some reason, the same value is being fed in twice (I'm
using two cores) to mpi_allreduce, which gives the wrong total_mass
out. I see different values going into mpi_allreduce, and the correct
total_mass, when I use the original summing method. This has led me to
conclude that the .quantities is not being done correctly here -
there's something wrong with the multi-level parallelism here I
think... or something. Does anyone have any ideas of what could be
going on? Thanks!

-- 
Stephen Skory
s at skory.us
http://stephenskory.com/
510.621.3687 (google voice)