pandas.core.categorical.Categorical.remove_unused_categories

Categorical.remove_unused_categories(inplace=False)

Removes categories which are not used.

Parameters :

inplace : boolean (default: False)

Whether or not to drop unused categories inplace or return a copy of this categorical with unused categories dropped.

Returns :

cat : Categorical with unused categories dropped or None if inplace.

See also

rename_categories, reorder_categories, add_categories, remove_categories, set_categories