pandas.NamedAgg — pandas 2.2.3 documentation (original) (raw)

class pandas.NamedAgg(column, aggfunc)[source]#

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

Subclass of typing.NamedTuple.

Parameters:

columnHashable

Column label in the DataFrame to apply aggfunc.

aggfuncfunction 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.