[Yt-dev] Parallel Hop

[Matthew Turk]

> It depends on your cosmological size - not the gridding. Smaller volumes need bigger padding, but I've discovered that 'a little goes a long way.' The logic is that you want any object to at least exist fully in at least one of the padded subvolumes. So if your biggest object is a 200 Kpc halo in a 20 Mpc volume, you need at least 0.01 padding (in simulation units). So for this example, I'd set padding to 0.02 or 0.03 to be conservative. Is there a simple way to estimate the largest object one can expect in a certain cosmological volume?

I personally feel we should allow the user to specify the minimum
percentage of the matter enclosed in their box, and provide a
relatively low value for this.  From this, a length scale drops out,
based on the total number of particles and the domain size.  We cannot
assume that the domain runs from 0 to 1 or that the three axes are
identical.

> I haven't found any either. In my opinion it's good to go.

Once we've addressed point 1, I agree.

-Matt