pandas.CategoricalIndex.remove_unused_categories#
- CategoricalIndex.remove_unused_categories(*args, **kwargs)[source]#
Remove categories which are not used.
- Parameters
- inplacebool, default False
Whether or not to drop unused categories inplace or return a copy of this categorical with unused categories dropped.
Deprecated since version 1.2.0.
- Returns
- catCategorical or None
Categorical with unused categories dropped or None if
inplace=True
.
See also
rename_categories
Rename categories.
reorder_categories
Reorder categories.
add_categories
Add new categories.
remove_categories
Remove the specified categories.
set_categories
Set the categories to the specified ones.
Examples
>>> c = pd.Categorical(['a', 'c', 'b', 'c', 'd']) >>> c ['a', 'c', 'b', 'c', 'd'] Categories (4, object): ['a', 'b', 'c', 'd']
>>> c[2] = 'a' >>> c[4] = 'c' >>> c ['a', 'c', 'a', 'c', 'c'] Categories (4, object): ['a', 'b', 'c', 'd']
>>> c.remove_unused_categories() ['a', 'c', 'a', 'c', 'c'] Categories (2, object): ['a', 'c']