Hi Stephen, On Fri, Feb 24, 2012 at 7:25 PM, Stephen Skory <s@skory.us> wrote:
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/ha...
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!
I'm not sure I understand -- is something wrong with *quantities-in-general*, or with the way it's being called in halo_objects? Can you investigate with a small dataset if the answer changes based on manually calculating versus using quantities in serial & parallel? -Matt
-- Stephen Skory s@skory.us http://stephenskory.com/ 510.621.3687 (google voice) _______________________________________________ yt-dev mailing list yt-dev@lists.spacepope.org http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org