pandas.core.resample.Resampler.size — pandas 2.2.3 documentation (original) (raw)

final Resampler.size()[source]#

Compute group sizes.

Returns:

DataFrame or Series

Number of rows in each group as a Series if as_index is True or a DataFrame if as_index is False.

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([1, 2, 3], index=lst) ser a 1 a 2 b 3 dtype: int64 ser.groupby(level=0).size() a 2 b 1 dtype: int64

data = [[1, 2, 3], [1, 5, 6], [7, 8, 9]] df = pd.DataFrame(data, columns=["a", "b", "c"], ... index=["owl", "toucan", "eagle"]) df a b c owl 1 2 3 toucan 1 5 6 eagle 7 8 9 df.groupby("a").size() a 1 2 7 1 dtype: int64

For Resampler:

ser = pd.Series([1, 2, 3], index=pd.DatetimeIndex( ... ['2023-01-01', '2023-01-15', '2023-02-01'])) ser 2023-01-01 1 2023-01-15 2 2023-02-01 3 dtype: int64 ser.resample('MS').size() 2023-01-01 2 2023-02-01 1 Freq: MS, dtype: int64