W3cubDocs

/pandas 0.25

pandas.CategoricalIndex.rename_categories

CategoricalIndex.rename_categories(self, *args, **kwargs) [source]

Rename categories.

Parameters:
new_categories : list-like, dict-like or callable
  • list-like: all items must be unique and the number of items in the new categories must match the existing number of categories.
  • dict-like: specifies a mapping from old categories to new. Categories not contained in the mapping are passed through and extra categories in the mapping are ignored.

    New in version 0.21.0.

  • callable : a callable that is called on all items in the old categories and whose return values comprise the new categories.

    New in version 0.23.0.

inplace : bool, default False

Whether or not to rename the categories inplace or return a copy of this categorical with renamed categories.

Returns:
cat : Categorical or None

With inplace=False, the new categorical is returned. With inplace=True, there is no return value.

Raises:
ValueError

If new categories are list-like and do not have the same number of items than the current categories or do not validate as categories

Examples

>>> c = pd.Categorical(['a', 'a', 'b'])
>>> c.rename_categories([0, 1])
[0, 0, 1]
Categories (2, int64): [0, 1]

For dict-like new_categories, extra keys are ignored and categories not in the dictionary are passed through

>>> c.rename_categories({'a': 'A', 'c': 'C'})
[A, A, b]
Categories (2, object): [A, b]

You may also provide a callable to create the new categories

>>> c.rename_categories(lambda x: x.upper())
[A, A, B]
Categories (2, object): [A, B]

© 2008–2012, AQR Capital Management, LLC, Lambda Foundry, Inc. and PyData Development Team
Licensed under the 3-clause BSD License.
https://pandas.pydata.org/pandas-docs/version/0.25.0/reference/api/pandas.CategoricalIndex.rename_categories.html