combineAdd NotImplementedError for SparseDataFrame

[craustin]

[also, should probably be combine_add]

from pandas import DataFrame
df = DataFrame()
sdf = df.to_sparse()
sdf.combineAdd(DataFrame())

pandas\core\frame.pyc in combineAdd(self, other)
3861 DataFrame
3862 """
-> 3863 return self.add(other, fill_value=0.)
3864
3865 def combineMult(self, other):

pandas\core\frame.pyc in f(self, other, axis, level, fill_value)
173 def f(self, other, axis=default_axis, level=None, fill_value=None):
174 if isinstance(other, DataFrame): # Another DataFrame
--> 175 return self._combine_frame(other, func, fill_value, level)
176 elif isinstance(other, Series):
177 return self._combine_series(other, func, fill_value, axis, level)

pandas\sparse\frame.pyc in _combine_frame(self, other, func, fill_value, level)
414
415 if fill_value is not None or level is not None:
--> 416 raise NotImplementedError
417
418 if not self and not other:

NotImplementedError: