xorbits.pandas.Series.map#

Series.map(arg, na_action=None, dtype=None, memory_scale=None, skip_infer=False)#

Map values of Series according to an input mapping or function.

Used for substituting each value in a Series with another value, that may be derived from a function, a dict or a Series.

Parameters

  • arg (function, collections.abc.Mapping subclass or Series) – Mapping correspondence.

  • na_action ({None, 'ignore'}, default None) – If ‘ignore’, propagate NaN values, without passing them to the mapping correspondence.

Returns

Same index as caller.

Return type

Series

See also

Series.apply

For applying more complex functions on a Series.

Series.replace

Replace values given in to_replace with value.

DataFrame.apply

Apply a function row-/column-wise.

DataFrame.map

Apply a function elementwise on a whole DataFrame.

Notes

When arg is a dictionary, values in Series that are not in the dictionary (as keys) are converted to NaN. However, if the dictionary is a dict subclass that defines __missing__ (i.e. provides a method for default values), then this default is used rather than NaN.

Examples

>>> s = pd.Series(['cat', 'dog', np.nan, 'rabbit'])  
>>> s  
0      cat
1      dog
2      NaN
3   rabbit
dtype: object

map accepts a dict or a Series. Values that are not found in the dict are converted to NaN, unless the dict has a default value (e.g. defaultdict):

>>> s.map({'cat': 'kitten', 'dog': 'puppy'})  
0   kitten
1    puppy
2      NaN
3      NaN
dtype: object

It also accepts a function:

>>> s.map('I am a {}'.format)  
0       I am a cat
1       I am a dog
2       I am a nan
3    I am a rabbit
dtype: object

To avoid applying the function to missing values (and keep them as NaN) na_action='ignore' can be used:

>>> s.map('I am a {}'.format, na_action='ignore')  
0     I am a cat
1     I am a dog
2            NaN
3  I am a rabbit
dtype: object
dtypenp.dtype, default None

Specify return type of the function. Must be specified when we cannot decide the return type of the function.

memory_scalefloat

Specify the scale of memory uses in the function versus input size.

skip_infer: bool, default False

Whether infer dtypes when dtypes or output_type is not specified

This docstring was copied from pandas.core.series.Series.