pandas.NamedAgg

classpandas.NamedAgg(column, aggfunc)[source]

Helper for column specific aggregation with control over output column names.

Subclass of typing.NamedTuple.

Parameters:

column:Hashable

Column label in the DataFrame to apply aggfunc.

aggfunc:function or str

Function to apply to the provided column. If string, the name of a built-in pandas function.

Examples

>>> df = pd.DataFrame({"key": [1, 1, 2], "a": [-1, 0, 1], 1: [10, 11, 12]})
>>> agg_a = pd.NamedAgg(column="a", aggfunc="min")
>>> agg_1 = pd.NamedAgg(column=1, aggfunc=lambda x: np.mean(x))
>>> df.groupby("key").agg(result_a=agg_a, result_1=agg_1)
     result_a  result_1
key
1          -1      10.5
2           1      12.0

Attributes

aggfunc	Alias for field number 1
column	Alias for field number 0

Methods

count(value, /)	Return number of occurrences of value.
index(value[, start, stop])	Return first index of value.