I'm trying to get started with basic Rockstar halo finding in yt (I typically use HOP, though current analysis requires Rockstar).    I'm having trouble with the following line:

>from yt.analysis_modules.halo_finding.rockstar.api import RockstarHaloFinder

which gives the error:  http://paste.yt-project.org/show/5224/

I'm running yt 3.0 (updated this morning).  I just installed Rockstar (I think) by switching on the INST_ROCKSTAR flag in the install script to 1, and re-running the script.  To be sure, I am running in an 'activated' yt, with the following ld_library_path:

>(yt-x86_64)thundersnow:~ desika$ echo $LD_LIBRARY_PATH
/Users/desika/yt-x86_64/lib:/opt/gsl/lib:

Though I note manually adding the directory: 

/Users/desika/yt-x86_64/src/yt-hg/yt/analysis_modules/halo_finding/rockstar/  

to my ld_library_path doesn't fix the problem.  Is this symptomatic of an erroneous installation on my part?   

thanks
-desika