[yt-users] Re: Ramses star- dark matter particle filter

I've been trying to use a filter with "particle_mass" < mass resolution cut in between stars and dark matter: def old(pfilter, data):

old_only = data[data, "particle_mass"].in_units('Msun')

filter = old_only < 4e6

return filter

However, I am uncertain if this is going to consider individual mass particles or combined mass particles in a cell.