DateParseError after upgrading matplotlib and others dependancies
Hi all,
using pandas 0.12, after upgrading matplotlib from 1.2.0 to 1.3.1, which in turn have upgraded numpy python-dateutil tornado pyparsing nose six, I can't now slice a datetime based dataframe:
In [16]: pm
Out[16]: 
<class 'pandas.core.frame.DataFrame'>
DatetimeIndex: 1584 entries, 2013-09-01 00:00:00 to 2013-11-05 23:00:00
Freq: H
Data columns (total 4 columns):
PM10_JUN      94  non-null values
PM10_MAG      155  non-null values
PS_CHALUS     97  non-null values
PS_ST_MATH    69  non-null values
dtypes: float64(4)

In [17]: pm.PM10_MAG["2013-09-17"]
Out[17]: 11.0
## In [18]: pm.PM10_MAG["2013-09-17":"2013-09-18"]

DateParseError                            Traceback (most recent call last)
<ipython-input-18-15808ec96c6d> in <module>()
----> 1 pm.PM10_MAG["2013-09-17":"2013-09-18"]

/usr/local/lib/python2.7/dist-packages/pandas/core/series.pyc in **getitem**(self, key)
    639             key = _check_bool_indexer(self.index, key)
    640 
--> 641         return self._get_with(key)
    642 
    643     def _get_with(self, key):

/usr/local/lib/python2.7/dist-packages/pandas/core/series.pyc in _get_with(self, key)
    652                 indexer = key
    653             else:
--> 654                 indexer = self.ix._convert_to_indexer(key, axis=0)
    655             return self._get_values(indexer)
    656         else:

/usr/local/lib/python2.7/dist-packages/pandas/core/indexing.pyc in _convert_to_indexer(self, obj, axis)
    558             else:
    559                 try:
--> 560                     indexer = labels.slice_indexer(start, stop, obj.step)
    561                 except Exception:
    562                     if _is_index_slice(obj):

/usr/local/lib/python2.7/dist-packages/pandas/tseries/index.pyc in slice_indexer(self, start, end, step)
   1225             raise TypeError('Cannot index datetime64 with float keys')
   1226 
-> 1227         return Index.slice_indexer(self, start, end, step)
   1228 
   1229     def slice_locs(self, start=None, end=None):

/usr/local/lib/python2.7/dist-packages/pandas/core/index.pyc in slice_indexer(self, start, end, step)
   1180         This function assumes that the data is sorted, so use at your own peril
   1181         """
-> 1182         start_slice, end_slice = self.slice_locs(start, end)
   1183 
   1184         # return a slice

/usr/local/lib/python2.7/dist-packages/pandas/tseries/index.pyc in slice_locs(self, start, end)
   1236                 try:
   1237                     if start:
-> 1238                         start_loc = self._get_string_slice(start).start
   1239                     else:
   1240                         start_loc = 0

/usr/local/lib/python2.7/dist-packages/pandas/tseries/index.pyc in _get_string_slice(self, key, use_lhs, use_rhs)
   1206         freq = getattr(self, 'freqstr',
   1207                        getattr(self, 'inferred_freq', None))
-> 1208         _, parsed, reso = parse_time_string(key, freq)
   1209         loc = self._partial_date_slice(reso, parsed, use_lhs=use_lhs, use_rhs=use_rhs)
   1210         return loc

/usr/local/lib/python2.7/dist-packages/pandas/tseries/tools.pyc in parse_time_string(arg, freq, dayfirst, yearfirst)
    238                                       yearfirst=yearfirst)
    239     except Exception, e:
--> 240         raise DateParseError(e)
    241 
    242     if parsed is None:

DateParseError: 'tuple' object has no attribute 'year'
