Hi All,

I'm having some issues with really basic halo finding on gadget snapshots in the bleeding edge version.  What I want to do is ID halos in a volume, save a list of the halos, and plot a projection plot with circles over the halos (all of which I think should be possible).

The principle script is:  http://paste.yt-project.org/show/4824/

The error I get when trying to save the halos is:

http://paste.yt-project.org/show/4822/

and in trying to annotate the halos on the projection plot is:

http://paste.yt-project.org/show/4823/

Am I either doing something wrong in my commands?  (hopefully as simple as that...) or are these not supported yet in the bleeding edge yt?

thanks
desika

ps. On another (related) note, is it possible to manually draw circles on a projection plot?  Or arrows, or tick marks, or anything that I could use to visually show off individual halos?