Date range creation with date_range in Pandas - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of daily date range creation

What is the output of the following code snippet that creates a daily date range?

Pandas

import pandas as pd

dates = pd.date_range(start='2024-01-01', end='2024-01-05')
print(dates)

A DatetimeIndex(['2024-01-01', '2024-01-03', '2024-01-05'], dtype='datetime64[ns]', freq='2D')

B DatetimeIndex(['2024-01-01', '2024-01-02', '2024-01-03', '2024-01-05'], dtype='datetime64[ns]', freq='D')

C DatetimeIndex(['2024-01-01', '2024-01-02', '2024-01-04', '2024-01-05'], dtype='datetime64[ns]', freq='D')

D DatetimeIndex(['2024-01-01', '2024-01-02', '2024-01-03', '2024-01-04', '2024-01-05'], dtype='datetime64[ns]', freq='D')

💡 Hint

Check how pandas.date_range includes both start and end dates by default with daily frequency.

The pd.date_range function with start and end dates and default daily frequency includes every day from start to end inclusive.

❓ data_output

intermediate

Number of periods in a weekly date range

How many dates are generated by this weekly date range starting on 2024-01-01 for 4 periods?

Pandas

import pandas as pd

dates = pd.date_range(start='2024-01-01', periods=4, freq='W')
print(len(dates))

A 1

B 4

C 5

D 3

💡 Hint

The periods parameter controls how many dates are generated.

The periods=4 means exactly 4 dates are generated at weekly intervals starting from the start date.

🔧 Debug

advanced

Identify the error in this date_range code

What error does this code produce and why? import pandas as pd dates = pd.date_range(start='2024-01-01', end='2024-01-10', freq='2X') print(dates)

Pandas

import pandas as pd

dates = pd.date_range(start='2024-01-01', end='2024-01-10', freq='2X')
print(dates)

A ValueError: Invalid frequency: 2X

B TypeError: freq must be a string

C SyntaxError: invalid syntax

D No error, prints dates every 2 days

💡 Hint

Check if '2X' is a valid frequency alias in pandas.

The frequency alias '2X' is invalid in pandas, causing a ValueError about invalid frequency.

🚀 Application

advanced

Create a date range for business days excluding weekends

Which code snippet correctly creates a date range of 5 business days starting from 2024-01-01?

A pd.date_range(start='2024-01-01', periods=5, freq='B')

B pd.date_range(start='2024-01-01', end='2024-01-05', freq='B')

C pd.date_range(start='2024-01-01', periods=5, freq='D')

D pd.date_range(start='2024-01-01', end='2024-01-10', freq='W')

💡 Hint

Business day frequency is represented by 'B' in pandas.

Using freq='B' generates dates only on business days (Monday to Friday). Using periods=5 gives exactly 5 business days.

🧠 Conceptual

expert

Understanding the effect of 'closed' parameter in date_range

Given the code below, which dates are included in the resulting date range? import pandas as pd dates = pd.date_range(start='2024-01-01', end='2024-01-05', closed='left') print(dates)

Pandas

import pandas as pd

dates = pd.date_range(start='2024-01-01', end='2024-01-05', closed='left')
print(dates)

A DatetimeIndex(['2024-01-01', '2024-01-05'], dtype='datetime64[ns]', freq='D')

B DatetimeIndex(['2024-01-02', '2024-01-03', '2024-01-04', '2024-01-05'], dtype='datetime64[ns]', freq='D')

C DatetimeIndex(['2024-01-01', '2024-01-02', '2024-01-03', '2024-01-04'], dtype='datetime64[ns]', freq='D')

D DatetimeIndex(['2024-01-02', '2024-01-03', '2024-01-04'], dtype='datetime64[ns]', freq='D')

💡 Hint

The 'closed' parameter controls which endpoint is excluded from the range.

With closed='left', the start date is excluded but the end date is included, so dates from 2024-01-02 to 2024-01-05 are included.