pandas.Series.idxmax

Return the row label of the maximum value.

If multiple values equal the maximum, the first row label with that value is returned.

param skipna

bool, default True

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

param axis

int, default 0

For compatibility with DataFrame.idxmax. Redundant for application on Series. *args, **kwargs Additional keywords have no effect but might be accepted for compatibility with NumPy.

return

Index Label of the maximum value.

raises

ValueError

If the Series is empty.

Limitations

Parameter axis is supported only with default value None. Parameter skipna cannot be False with data of string type.

Examples

Getting the row label of the maximum value.

import numpy as np
import pandas as pd
from numba import njit


@njit
def series_idxmax():
    s = pd.Series([4, np.nan, 2, 1], index=['A', 'B', 'C', 'D'])

    return s.idxmax()  # Expect index of maximum value A


print(series_idxmax())

$ python ./series/series_idxmax.py
A

See also

Series.idxmin

Return index label of the first occurrence of minimum of values.

numpy.absolute

Return indices of the maximum values along the given axis.

DataFrame.idxmax

Return index of first occurrence of maximum over requested axis.