pandas.DataFrame.first_valid_index — pandas 3.0.0.dev0+2102.g839747c3f6 documentation (original) (raw)

DataFrame.first_valid_index()[source]#

Return index for first non-missing value or None, if no value is found.

See the User Guide for more information on which values are considered missing.

Returns:

type of index

Index of first non-missing value.

Examples

For Series:

s = pd.Series([None, 3, 4]) s.first_valid_index() 1 s.last_valid_index() 2

s = pd.Series([None, None]) print(s.first_valid_index()) None print(s.last_valid_index()) None

If all elements in Series are NA/null, returns None.

s = pd.Series() print(s.first_valid_index()) None print(s.last_valid_index()) None

If Series is empty, returns None.

For DataFrame:

df = pd.DataFrame({"A": [None, None, 2], "B": [None, 3, 4]}) df A B 0 NaN NaN 1 NaN 3.0 2 2.0 4.0 df.first_valid_index() 1 df.last_valid_index() 2

df = pd.DataFrame({"A": [None, None, None], "B": [None, None, None]}) df A B 0 None None 1 None None 2 None None print(df.first_valid_index()) None print(df.last_valid_index()) None

If all elements in DataFrame are NA/null, returns None.

df = pd.DataFrame() df Empty DataFrame Columns: [] Index: [] print(df.first_valid_index()) None print(df.last_valid_index()) None

If DataFrame is empty, returns None.