pandas.CategoricalIndex.add_categories

CategoricalIndex.add_categories(*args, **kwargs)

Add new categories.

new_categories will be included at the last/highest place in the categories and will be unused directly after this call.

Parameters:

new_categories : category or list-like of category

The new categories to be included.

inplace : boolean (default: False)

Whether or not to add the categories inplace or return a copy of this categorical with added categories.

Returns:

cat : Categorical with new categories added or None if inplace.

Raises:

ValueError

If the new categories include old categories or do not validate as categories