pandas.api.typing.Resampler.first — pandas 3.0.0rc0+33.g1fd184de2a documentation (original) (raw)

final Resampler.first(numeric_only=False, min_count=0, skipna=True)[source]#

Compute the first non-null entry of each column.

Parameters:

numeric_onlybool, default False

Include only float, int, boolean columns.

min_countint, default 0

The required number of valid values to perform the operation. If fewer than min_count non-NA values are present the result will be NA.

skipnabool, default True

Exclude NA/null values. If an entire group is NA, the result will be NA.

Returns:

Series or DataFrame

First values within each group.

See also

core.resample.Resampler.last

Compute the last non-null value in each group.

core.resample.Resampler.mean

Compute mean of groups, excluding missing values.

Examples

s = pd.Series( ... [1, 2, 3, 4], ... index=pd.DatetimeIndex( ... ["2023-01-01", "2023-01-15", "2023-02-01", "2023-02-15"] ... ), ... ) s 2023-01-01 1 2023-01-15 2 2023-02-01 3 2023-02-15 4 dtype: int64 s.resample("MS").first() 2023-01-01 1 2023-02-01 3 Freq: MS, dtype: int64