Accessor object for categorical properties of the Series values.
Examples
>>> s = pd.Series(list("abbccc")).astype("category")
>>> s
0 a
1 b
2 b
3 c
4 c
5 c
dtype: category
Categories (3, object): ['a', 'b', 'c']
>>> s.cat.categories
Index(['a', 'b', 'c'], dtype='object')
>>> s.cat.rename_categories(list("cba"))
0 c
1 b
2 b
3 a
4 a
5 a
dtype: category
Categories (3, object): ['c', 'b', 'a']
>>> s.cat.reorder_categories(list("cba"))
0 a
1 b
2 b
3 c
4 c
5 c
dtype: category
Categories (3, object): ['c', 'b', 'a']
>>> s.cat.add_categories(["d", "e"])
0 a
1 b
2 b
3 c
4 c
5 c
dtype: category
Categories (5, object): ['a', 'b', 'c', 'd', 'e']
>>> s.cat.remove_categories(["a", "c"])
0 NaN
1 b
2 b
3 NaN
4 NaN
5 NaN
dtype: category
Categories (1, object): ['b']
>>> s1 = s.cat.add_categories(["d", "e"])
>>> s1.cat.remove_unused_categories()
0 a
1 b
2 b
3 c
4 c
5 c
dtype: category
Categories (3, object): ['a', 'b', 'c']
>>> s.cat.set_categories(list("abcde"))
0 a
1 b
2 b
3 c
4 c
5 c
dtype: category
Categories (5, object): ['a', 'b', 'c', 'd', 'e']
>>> s.cat.as_ordered()
0 a
1 b
2 b
3 c
4 c
5 c
dtype: category
Categories (3, object): ['a' < 'b' < 'c']
>>> s.cat.as_unordered()
0 a
1 b
2 b
3 c
4 c
5 c
dtype: category
Categories (3, object): ['a', 'b', 'c']
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© 2011–2025, Open source contributors
Licensed under the 3-clause BSD License.
https://pandas.pydata.org/pandas-docs/version/2.3.0/reference/api/pandas.Series.cat.html