Rename categories.
New categories which will replace old categories.
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.
callable : a callable that is called on all items in the old categories and whose return values comprise the new categories.
Categorical with renamed categories.
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
See also
reorder_categoriesReorder categories.
add_categoriesAdd new categories.
remove_categoriesRemove the specified categories.
remove_unused_categoriesRemove categories which are not used.
set_categoriesSet the categories to the specified ones.
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']
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https://pandas.pydata.org/pandas-docs/version/2.3.0/reference/api/pandas.Series.cat.rename_categories.html