New issue 1267: Profile datasets don't save profile.field_info dict data https://bitbucket.org/yt_analysis/yt/issues/1267/profile-datasets-dont-save

Nathan Goldbaum:

This is illustrated by the following script:

``` import yt ds = yt.load('IsolatedGalaxy/galaxy0030/galaxy0030') ad = ds.all_data() prof = yt.create_profile(ad, [('gas', 'H_number_density'), ('gas', 'temperature')\ ], fields='cell_mass') print (prof.field_info) prof.save_as_dataset() prof_ds = yt.load('galaxy0030_Profile2D.h5') print (prof_ds.profile.field_info) plot = yt.PhasePlot(prof_ds.data, "H_number_density", "temperature", "cell_mass",\ weight_field=None) ```

On my machine this prints:

``` {('gas', 'temperature'): Alias Field for "('enzo', 'Temperature')" (gas, temperature): (units: K), ('gas', 'H_number_density'): Derived Field (gas, H_number_density): (units: cm**(-3)), ('gas', 'cell_mass'): Derived Field (gas, cell_mass): (units: g)} {} ```

And then crashes with the following traceback:

``` Traceback (most recent call last): File "test.py", line 11, in <module> weight_field=None) File "/Users/goldbaum/Documents/yt-hg/yt/visualization/profile_plotter.py", line 745, in __init__ if isinstance(data_source.ds, YTProfileDataset): File "/Users/goldbaum/Documents/yt-hg/yt/visualization/profile_plotter.py", line 775, in _initialize_instance obj._setup_plots() File "/Users/goldbaum/Documents/yt-hg/yt/visualization/profile_plotter.py", line 856, in _setup_plots x_scale, y_scale, z_scale = self._get_field_log(f, self.profile) File "/Users/goldbaum/Documents/yt-hg/yt/visualization/profile_plotter.py", line 815, in _get_field_log zfi = profile.field_info[field_z] KeyError: ('data', 'cell_mass') ```

@brittonsmith any chance you can take a look at this?