, na_action=None)[source]#

Map values using an input mapping or function.

mapperfunction, dict, or Series

Mapping correspondence.

na_action{None, ‘ignore’}

If ‘ignore’, propagate NA values, without passing them to the mapping correspondence.

Union[Index, MultiIndex]

The output of the mapping function applied to the index. If the function returns a tuple with more than one element a MultiIndex will be returned.


>>> idx = pd.Index([1, 2, 3])
>>>{1: 'a', 2: 'b', 3: 'c'})
Index(['a', 'b', 'c'], dtype='object')

Using map with a function:

>>> idx = pd.Index([1, 2, 3])
>>>'I am a {}'.format)
Index(['I am a 1', 'I am a 2', 'I am a 3'], dtype='object')
>>> idx = pd.Index(['a', 'b', 'c'])
>>> x: x.upper())
Index(['A', 'B', 'C'], dtype='object')