Pandas concat cannot take an ImmutableDict

[berquist]

>>> pd.concat(scores_per_document)
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "/Users/berquist/.anaconda/envs/event-extraction-3.6/lib/python3.6/site-packages/pandas/core/reshape/concat.py", line 255, in concat
    sort=sort,
  File "/Users/berquist/.anaconda/envs/event-extraction-3.6/lib/python3.6/site-packages/pandas/core/reshape/concat.py", line 332, in __init__
    raise TypeError(msg)
TypeError: cannot concatenate object of type '<class 'str'>'; only Series and DataFrame objs are valid
>>> type(scores_per_document)
immutablecollections._immutabledict.RegularDictBackedImmutableDict
>>> type(dict(scores_per_document))
<class 'dict'>
>>> pd.concat(dict(scores_per_document))
                                                              tp   fp   fn  precision  recall     f1
AFP_ENG_20030323.0020              Personnel.Start-Position  0.0  0.0  0.0        0.0     0.0    0.0
                                   Personnel.End-Position    0.0  0.0  0.0        0.0     0.0    0.0
                                   Personnel.Nominate        0.0  0.0  0.0        0.0     0.0    0.0
                                   Personnel.Elect           0.0  0.0  0.0        0.0     0.0    0.0
                                   Movement.Transport        3.0  0.0  0.0      100.0   100.0  100.0
...                                                          ...  ...  ...        ...     ...    ...
AGGRESSIVEVOICEDAILY_20050124.1354 Justice.Execute           0.0  0.0  0.0        0.0     0.0    0.0
                                   Justice.Extradite         0.0  0.0  0.0        0.0     0.0    0.0
                                   Justice.Appeal            0.0  0.0  0.0        0.0     0.0    0.0
                                   Justice.Pardon            0.0  0.0  0.0        0.0     0.0    0.0
                                   __ALL_EVENTS_COMBINED__   2.0  0.0  0.0      100.0   100.0  100.0

[660 rows x 6 columns]

[gabbard]

@berquist : I don't think this is something we can do anything about. The problem is here: https://github.com/pandas-dev/pandas/blob/83812e1ba93b7857b8222e6651c823a88223472f/pandas/core/reshape/concat.py#L293 . You could file an issue+PR with pandas requesting it become isinstance(objs, Mapping).

[gabbard]

There is a Pandas issue corresponding to this: pandas-dev/pandas#6792