[yt-users] subregion halo find

[Stephen Skory]

Hi Geoffrey,

> Hi Stephen, I'm trying to do halo finding in a subregion of the box, but do
> the various halo finders know that the boundary conditions are no longer
> periodic?  If periodic BC is on by default, is there a flag to switch off
> periodicity during the subregion halo find?

I think that this question is ill-posed in the sense that I'm not sure
that anything good will happen if you try halo-finding in a region
that touches one of the periodic box edges. The subregion halo finding
is a kludge that is primarily meant for looking at stuff only where
you're interested, say in the center of your nested-grid simulation,
far away from the boundaries.

To answer your specific question as best I can: No, there is nothing
to turn off the periodic boundaries with subregion finding. But I
think you shouldn't be doing subregion finding where the boundaries
are a concern. I think Bad Things (tm) will happen.

Let me know if that doesn't help!

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