DOC: Clarify what Categorical takes.
REF: Deprecate Factor for Categorical.
ENH/DOC: Allow levels=None for Categorical
TST: Test Categorical constructor with levels=None
DOC: Coherent english in docstring
TST: Test describe method of Categorical
ENH: Add a describe method to Categorical.
REF: Remove Factor alias left by mistake.
ENH: Add levels=None in deprecated class too.
DOC: Factor -> Categorical.
REF: Factor -> Categorical.
ENH add date to DatetimeIndex
TST: Test Series.sort with ascending
ENH: Allow sorting of Series in ascending order
BUG: (GH3626) issue with alignment of a DataFrame setitem with a piece of another DataFrame
BUG: validate ndarray size correctly with assigning pieces to a DataFrame
Merge pull request #3614 from hayd/add_date_to_datetimeindex

ENH add date to DatetimeIndex
Merge pull request #3632 from jreback/assign_df

BUG: (GH3626) issue with alignment of a DataFrame setitem with a piece of another DataFrame
ENH: add regex functionality to DataFrame.replace

add default of None to to_replace

add ability to pass regex as to_replace regex

Remove cruft

more tests and add ability to pass regex and value

Make exceptions more clear; push examples to missing_data.rst

remove interpolation call

make inplace work across axes in interpolate method

ability to use nested dicts for regexs and others

mostly doc updates

formatting

infer_types correction

rls notes
DOC: minor edits in missing_data.rst and io/stata edits