[yt-dev] Issue #781: Deposited particle fields in Enzo not working (yt_analysis/yt)

[John Wise]

New issue 781: Deposited particle fields in Enzo not working
https://bitbucket.org/yt_analysis/yt/issue/781/deposited-particle-fields-in-enzo-not

John Wise:

yt-3.0 cannot generate deposited fields in Enzo datasets.  For example, when I'm trying to access either 'dm_density', ['deposit', 'all_density'], or ['cic_particle_velocity_x'] in a single grid with the following lines


```
#!python

pf = load(sys.argv[-1])
g = pf.h.grids[0]
dm = g['dm_density']
```


It crashes with the following error,


```
#!python

yt.utilities.exceptions.YTCouldNotGenerateField: Could field '('all', 'particle_position_x')' in output_0000 could not be generated.
```


even though it's in the dataset, and executing g['all', 'particle_position_x'] gives no errors.  It looks like _generate_particle_field() is returning None.