[yt-dev] Issue #755: YTArray is not pickleable (yt_analysis/yt)

[Nathan Goldbaum]

New issue 755: YTArray is not pickleable
https://bitbucket.org/yt_analysis/yt/issue/755/ytarray-is-not-pickleable

Nathan Goldbaum:

After applying the following diff:


```
#!diff

diff -r d20587c1602e yt/data_objects/yt_array.py
--- a/yt/data_objects/yt_array.py       Tue Dec 17 14:35:41 2013 -0500
+++ b/yt/data_objects/yt_array.py       Wed Dec 18 14:18:00 2013 -0800
@@ -261,7 +261,7 @@
         """

         """
-        if obj is None:
+        if obj is None and hasattr(self, 'units'):
             return
         self.units = getattr(obj, 'units', None)
```

You can try the following test script which illustrates the problem:

```
#!python

○ cat test_pickle.py
from yt.data_objects.yt_array import YTArray as array
import cPickle as pickle

arr = array([1,2,3], 'g')

with open('save.p', 'wb') as f:
    pickle.dump(arr, f)

with open('save.p', 'rb') as f:
    data_read = pickle.load(f)

print arr
print data_read
```

On my machine, this prints:


```
[1 2 3] g
[1 2 3] None
```

This is related to #754 and #743.