New issue 835: Field detection issue for Tipsy datasets https://bitbucket.org/yt_analysis/yt/issue/835/field-detection-issue-for-tip... Nathan Goldbaum: The following script: ``` #!python from yt.mods import * ds = load('TipsyGalaxy/galaxy.00300', n_ref=8) ds.derived_field_list dd = ds.all_data() xcoord = dd['Gas','Coordinates'][:,0].v ycoord = dd['Gas','Coordinates'][:,1].v slc = SlicePlot(ds, 'z', ('gas','density'), width=(40, 'kpc'), center='m') slc.save() ``` Produces the following traceback: ``` #!python traceback Traceback (most recent call last): File "test.py", line 7, in <module> slc = SlicePlot(ds, 'z', ('gas','density'), width=(40, 'kpc'), center='m') File "/Users/goldbaum/Documents/yt-hg/yt/visualization/plot_window.py", line 1749, in SlicePlot return AxisAlignedSlicePlot(pf, normal, fields, *args, **kwargs) File "/Users/goldbaum/Documents/yt-hg/yt/visualization/plot_window.py", line 972, in __init__ (bounds, center) = get_window_parameters(axis, center, width, pf) File "/Users/goldbaum/Documents/yt-hg/yt/visualization/plot_window.py", line 166, in get_window_parameters center = get_sanitized_center(center, pf) File "/Users/goldbaum/Documents/yt-hg/yt/visualization/plot_window.py", line 146, in get_sanitized_center v, center = pf.h.find_max("density") File "/Users/goldbaum/Documents/yt-hg/yt/data_objects/static_output.py", line 533, in find_max source.quantities["MaxLocation"](field) File "/Users/goldbaum/Documents/yt-hg/yt/data_objects/derived_quantities.py", line 527, in __call__ rv = super(MaxLocation, self).__call__(field) File "/Users/goldbaum/Documents/yt-hg/yt/data_objects/derived_quantities.py", line 59, in __call__ sto.result = self.process_chunk(ds, *args, **kwargs) File "/Users/goldbaum/Documents/yt-hg/yt/data_objects/derived_quantities.py", line 538, in process_chunk if data[field].size > 0: File "/Users/goldbaum/Documents/yt-hg/yt/data_objects/data_containers.py", line 205, in __getitem__ f = self._determine_fields([key])[0] File "/Users/goldbaum/Documents/yt-hg/yt/data_objects/data_containers.py", line 453, in _determine_fields finfo = self.pf._get_field_info(ftype, fname) File "/Users/goldbaum/Documents/yt-hg/yt/data_objects/static_output.py", line 493, in _get_field_info raise YTFieldNotFound((ftype, fname), self) yt.utilities.exceptions.YTFieldNotFound: Could not find field '('all', 'density')' in galaxy.00300. ``` When I remove the call to `ds.derived_field_list` I get a different failure: ``` #!python traceback Traceback (most recent call last): File "test.py", line 4, in <module> xcoord = dd['Gas','Coordinates'][:,0].v File "/Users/goldbaum/Documents/yt-hg/yt/data_objects/data_containers.py", line 212, in __getitem__ self.get_data(f) File "/Users/goldbaum/Documents/yt-hg/yt/data_objects/data_containers.py", line 556, in get_data self.index._identify_base_chunk(self) File "/Users/goldbaum/Documents/yt-hg/yt/geometry/particle_geometry_handler.py", line 140, in _identify_base_chunk self.regions.identify_data_files(dobj.selector)] File "/Users/goldbaum/Documents/yt-hg/yt/data_objects/data_containers.py", line 512, in selector self._selector = sclass(self) File "selection_routines.pyx", line 626, in yt.geometry.selection_routines.RegionSelector.__init__ (yt/geometry/selection_routines.c:9845) File "/Users/goldbaum/Documents/yt-hg/yt/units/yt_array.py", line 753, in __getitem__ ret = super(YTArray, self).__getitem__(item) IndexError: 0-d arrays can't be indexed ``` Finally, when I remove the lines that create and access data inside the `all_data` object, the script runs successfully and the plot is saved to disk. This uses the TipsyGalaxy dataset which will be uploaded to yt-project.org/data shortly.