[yt-dev] Issue #1187: ARTIO data cannot create Ray data objects (yt_analysis/yt)

[Cameron Hummels]

New issue 1187: ARTIO data cannot create Ray data objects
https://bitbucket.org/yt_analysis/yt/issues/1187/artio-data-cannot-create-ray-data-objects

Cameron Hummels:

There appears to be something wrong with generating a `ray` object in ARTIO datasets.  One can view its fields (e.g. 'density') no problem, but in order to view the ordered list of values along the ray (using the parametric variable `t`), it fails.  See [here](http://yt-project.org/docs/dev/faq/index.html#why-are-the-values-in-my-ray-object-out-of-order) for a full description of `t`'s use.  It appears to occur in the 2 ARTIO datasets I've tested, and I have no problems with other frontends in accessing the contents of the 't' field in the ray.  

I've generated a simple script (using the [publicly available artio dataset](http://yt-project.org/data/)) to demonstrate this:


```
#!python

import yt
ds = yt.load('sizmbhloz-clref04SNth-rs9_a0.9011/sizmbhloz-clref04SNth-rs9_a0.9011.art')
ray = ds.ray(ds.domain_left_edge, ds.domain_right_edge)
print "first density value in ray: %f" % ray['density'][0]
print "first t value in ray: %f" % ray['t'][0]
```
with output/traceback here:

http://paste.yt-project.org/show/6319/