Re: [yt-dev] Make DomainSubsets a subclass of YTSelectionContainer?

On Wed, Apr 17, 2013 at 4:35 PM, Douglas Harvey Rudd wrote:

Hi Matt,

I'm +1 on specifying the DomainSubset interface though subclasses, and it makes sense to integrate it with selection.

Awesome.

One question I have relating to deposition in particular is whether the spatial fields are expected to impose any sort of order on the octs they return. If we select a region including both particles and octs, but the two are completely unordered, matching one set to the other may be very expensive.

That's a *really* good point ,and one that I had hoped we could address through chunking. I *definitely* want to avoid an NxM search of particles to octs, so I was thinking two prongs to this: 1) This will happen inside a chunked iteration if at all possible, which reduces the search space for particles considerably 2) We will utilize the existing octree infrastructure (i.e., OctContainer and its subclasses) to identify the octs to which particles belong I think this should make it fast enough, as we'll be searching within a chunk, which should already be relatively small. But we can certainly adjust this later.

Do the deposition routines already use some organization scheme (oct tree, say) to match particles to grids?

Doug

On Apr 17, 2013, at 3:24 PM, Matthew Turk wrote:

...

Hi all,

Today in IRC, Chris and I went back and forth on the particle deposition stuff in advance of the meeting next week. My task right now is to come up with spatial field chunking for Octs in a consistent way; of course I'll write this up into the extant YTEP, which will allow for feedback particularly from ARTIO, ART and RAMSES folks, but as a quick first pass I was wondering what everyone thought of:

1) Unifying DomainSubsets into a single object with subclasses 2) Making that new base class a subclass, itself, of YTSelectionContainer

This would mean that this new base class would be very similar to the GridPatch object -- which it already is -- and would implement, most crucially, the __getitem__ accessor pattern. This would return a 2x2x2xNoct field.

[+-][01]? Specifically, Doug, Chris, and SamL?

Sidenote: I discovered that we will not have to rewrite spatial fields that currently work for grids; my understanding of the numpy broadcasting system was not complete, and I didn't realize that this script does *exactly what I want it to.

http://paste.yt-project.org/show/3391/

This means that our Oct spatial fields will be (2+NGZ*2, 2+NGZ*2, 2+NGZ*2, NOCT) shaped. _______________________________________________ yt-dev mailing list yt-dev@lists.spacepope.org http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org

_______________________________________________ yt-dev mailing list yt-dev@lists.spacepope.org http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org