How to check whether the day is a weekday or not using Pandas in Python?

Python pandas library provides several functions to check whether a day is a weekday or weekend, including weekday(), day_name(), and isoweekday(). These functions work with pandas datetime objects to identify the day of the week.

Using the weekday() Function

The weekday() function returns the day of the week as an integer, where 0 represents Monday, 1 represents Tuesday, and so on up to 6 for Sunday ?

import pandas as pd

date = pd.to_datetime('2023-03-25')
day_number = date.weekday()
print(f"Day number: {day_number}")

if day_number < 5:
    print(f"{date.date()} is a Weekday")
else:
    print(f"{date.date()} is a Weekend")

Day number: 5
2023-03-25 is a Weekend

Example with Function

Here's a reusable function to check any date ?

import pandas as pd

def check_weekday(date_string):
    date = pd.to_datetime(date_string)
    day_number = date.weekday()
    
    if day_number < 5:
        return f"{date.date()} is a Weekday (Day {day_number})"
    else:
        return f"{date.date()} is a Weekend (Day {day_number})"

# Test with different dates
print(check_weekday('2023-03-23'))  # Thursday
print(check_weekday('2023-03-25'))  # Saturday

2023-03-23 is a Weekday (Day 3)
2023-03-25 is a Weekend (Day 5)

Using the day_name() Function

The day_name() function returns the actual name of the day as a string, making it more readable ?

import pandas as pd

date = pd.to_datetime('2023-03-25')
day_name = date.day_name()
print(f"Day name: {day_name}")

weekdays = ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday']
if day_name in weekdays:
    print(f"{date.date()} is a Weekday")
else:
    print(f"{date.date()} is a Weekend")

Day name: Saturday
2023-03-25 is a Weekend

Example with Multiple Dates

Checking multiple dates using a DataFrame ?

import pandas as pd

dates = ['2023-03-20', '2023-03-21', '2023-03-22', '2023-03-23', '2023-03-24']
df = pd.DataFrame({'date': pd.to_datetime(dates)})

df['day_name'] = df['date'].dt.day_name()
df['is_weekday'] = df['day_name'].isin(['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday'])

print(df)

        date   day_name  is_weekday
0 2023-03-20     Monday        True
1 2023-03-21    Tuesday        True
2 2023-03-22  Wednesday        True
3 2023-03-23   Thursday        True
4 2023-03-24     Friday        True

Using isoweekday() Function

The isoweekday() function follows the ISO standard where Monday is 1, Tuesday is 2, and Sunday is 7 ?

import pandas as pd

date = pd.to_datetime('2023-03-25')
iso_day = date.isoweekday()
print(f"ISO day number: {iso_day}")

if iso_day < 6:  # Monday(1) to Friday(5)
    print(f"{date.date()} is a Weekday")
else:  # Saturday(6) or Sunday(7)
    print(f"{date.date()} is a Weekend")

ISO day number: 6
2023-03-25 is a Weekend

Example with Monday Date

import pandas as pd

date = pd.to_datetime('2022-11-21')  # Monday
iso_day = date.isoweekday()
print(f"ISO day number: {iso_day}")

if iso_day < 6:
    print(f"{date.date()} is a Weekday")
else:
    print(f"{date.date()} is a Weekend")

ISO day number: 1
2022-11-21 is a Weekday

Comparison of Methods

Conclusion

Use weekday() for simple integer-based checks, day_name() for readable string comparisons, and isoweekday() when following ISO standards. All three methods effectively identify weekdays vs weekends in pandas datetime objects.