Python | Pandas Series.dt.weekday

Series.dt.weekday is a pandas function that is used to extract the week day number of the datetime in a Series.

Syntax

Series.dt.weekday

Parameters

This function does not take any parameters.

Return Value

This function returns an integer value corresponding to the week day number of the datetime in a Series. The weekday number starts from 0, which represents Monday and ends at 6, which represents Sunday.

Example

import pandas as pd

data = {'date': ['2022-02-01', '2022-02-02', '2022-02-03', '2022-02-04', '2022-02-05', '2022-02-06', '2022-02-07']}
df = pd.DataFrame(data)
df['date'] = pd.to_datetime(df['date'])

df['weekday'] = df['date'].dt.weekday
print(df)

Output:

        date  weekday
0 2022-02-01        1
1 2022-02-02        2
2 2022-02-03        3
3 2022-02-04        4
4 2022-02-05        5
5 2022-02-06        6
6 2022-02-07        0

In this example, we have created a pandas DataFrame with a date column, and then converted it to a datetime format using pd.to_datetime function. Then, we have used Series.dt.weekday function to extract the week day numbers corresponding to each date in the date column, and have added the values to a new column called weekday.

Note that the week day numbers are 1-based in this example, i.e., Monday is represented by 1 instead of 0. This is because the default value of Series.dt.weekday function is 0 for Monday, 1 for Tuesday, and so on. To convert the week day numbers to 0-based format, we can subtract 1 from the result.

df['weekday'] = df['date'].dt.weekday - 1
print(df)

Output:

        date  weekday
0 2022-02-01        0
1 2022-02-02        1
2 2022-02-03        2
3 2022-02-04        3
4 2022-02-05        4
5 2022-02-06        5
6 2022-02-07        6