def sort_values(self, by, axis=0, ascending=True,
                    kind='quicksort', na_position='last'):
        """Sort by the values along either axis

        Wrapper around the :meth:`pandas.DataFrame.sort_values` method.
        """
        return self._frame.sort_values(by, axis=axis, ascending=ascending,
                                       inplace=False, kind=kind,
                                       na_position=na_position)