[yt-users] Problem using covering_grid as data_source for the photon_simulator

[Markus Haider]

Hi,

I wanted to use the photon simulator for mock x-ray observations on 
single cells and line of sights using single cells. For this I wanted to 
select the cells using covering_grid, but then I get the following error:

photon_simulator.py is doing
  delta_min, delta_max = data_source.quantities.extrema("d%s"%ax)
and the result is
YTDataSelectorNotImplemented: Data selector 'covering_grid' not implemented.

But maybe covering_grid is not the right thing for what I had in mind, 
how would you select the cells to pass as data_source to the photon 
simulator?

Cheers,
Markus