narwhals.Series.cat
get_categories
get_categories() -> SeriesT
Get unique categories from column.
Warning
This is deprecated and it will be removed in a future version, as Polars
removed its own cat.get_categories.
To get the distinct values present in a Categorical column, use
Series.unique.
For the fixed category list of an Enum, use its dtype.categories.
Until it is removed, it is implemented as
unique(maintain_order=True).drop_nulls().cast(String), so it returns only
the values which are actually present, in order of appearance.
Note
In narwhals.stable.v1 and narwhals.stable.v2 this stays available, and
keeps dispatching to each backend's native implementation.
Examples:
>>> import pandas as pd
>>> import narwhals.stable.v2 as nw
>>> s_native = pd.Series(["apple", "mango", "mango"], dtype="category")
>>> s = nw.from_native(s_native, series_only=True)
>>> s.cat.get_categories().to_native()
0 apple
1 mango
dtype: str