pandas.core.groupby.SeriesGroupBy.cumsum#
- SeriesGroupBy.cumsum(axis=<no_default>, *args, **kwargs)[source]#
Cumulative sum for each group.
- Returns:
- Series or DataFrame
See also
Series.groupby
Apply a function groupby to a Series.
DataFrame.groupby
Apply a function groupby to each row or column of a DataFrame.
Examples
For SeriesGroupBy:
>>> lst = ['a', 'a', 'b'] >>> ser = pd.Series([6, 2, 0], index=lst) >>> ser a 6 a 2 b 0 dtype: int64 >>> ser.groupby(level=0).cumsum() a 6 a 8 b 0 dtype: int64
For DataFrameGroupBy:
>>> data = [[1, 8, 2], [1, 2, 5], [2, 6, 9]] >>> df = pd.DataFrame(data, columns=["a", "b", "c"], ... index=["fox", "gorilla", "lion"]) >>> df a b c fox 1 8 2 gorilla 1 2 5 lion 2 6 9 >>> df.groupby("a").groups {1: ['fox', 'gorilla'], 2: ['lion']} >>> df.groupby("a").cumsum() b c fox 8 2 gorilla 10 7 lion 6 9