Back to the future

A new update to the data pipeline feeding into the ride_sharing DataFrame has been updated to register each ride's date. This information is stored in the ride_date column of the type object, which represents strings in pandas.

A bug was discovered which was relaying rides taken today as taken next year. To fix this, you will find all instances of the ride_date column that occur anytime in the future, and set the maximum possible value of this column to today's date. Before doing so, you would need to convert ride_date to a datetime object.

The datetime package has been imported as dt, alongside all the packages you've been using till now.

This exercise is part of the course

Cleaning Data in Python

Exercise instructions

Convert ride_date to a datetime object using to_datetime(), then convert the datetime object into a date and store it in ride_dt column.
Create the variable today, which stores today's date by using the dt.date.today() function.
For all instances of ride_dt in the future, set them to today's date.
Print the maximum date in the ride_dt column.

Hands-on interactive exercise

Have a go at this exercise by completing this sample code.

# Convert ride_date to date
ride_sharing['ride_dt'] = pd.____(____['____']).dt.date

# Save today's date
today = ____

# Set all in the future to today's date
ride_sharing.____[____['____'] > ____, '____'] = ____

# Print maximum of ride_dt column
print(ride_sharing['ride_dt'].____())

Edit and Run Code

This exercise is part of the course

Cleaning Data in Python

IntermediateSkill Level

4.8+

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In this chapter, you'll learn how to overcome some of the most common dirty data problems. You'll convert data types, apply range constraints to remove future data points, and remove duplicated data points to avoid double-counting.

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