Hi everyone,

I get an error when executing the simple script below:

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from yt.mods import *
output = 'DD0010/data0010'
pf = load(output)
region = pf.h.region([0.5,0.5,0.5],[0.0,0.0,0.0],[1.0,1.0,1.0])
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I have pasted the output there: http://paste.yt-project.org/show/awqlzVK7mAhtiIVihFfC/
I think the problem is that my simulation has only 2 particles (no gas) and both particles are in subgrids so the root grid is empty:

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[19:46:54] Obiwan:$ h5ls DD0010/data0010.cpu0000
Grid00000001             Group
Grid00000002             Group
Metadata                 Group
[19:47:09] Obiwan:$ h5ls DD0010/data0010.cpu0000/Grid00000001
[19:47:15] Obiwan:$ h5ls DD0010/data0010.cpu0000/Grid00000002
particle_index           Dataset {2}
particle_mass            Dataset {2}
particle_position_x      Dataset {2}
particle_position_y      Dataset {2}
particle_position_z      Dataset {2}
particle_type            Dataset {2}
particle_velocity_x      Dataset {2}
particle_velocity_y      Dataset {2}
particle_velocity_z      Dataset {2}
------------------------------------------------------------------------------

I would really appreciate if someone could help me to fix this.
Thanks a lot,

JC