Back to the future

Something has gone wrong and it looks like you have data with dates from the future, which is way outside of the date range you expected to be working with. To fix this, you'll need to remove any rides from the dataset that have a date in the future. Before you can do this, the date column needs to be converted from a character to a Date. Having these as Date objects will make it much easier to figure out which rides are from the future, since R makes it easy to check if one Date object is before (<) or after (>) another.

dplyr and assertive are loaded and bike_share_rides is available.

This exercise is part of the course

Cleaning Data in R

Exercise instructions

Convert the date column of bike_share_rides from character to the Date data type.
Assert that all values in the date column happened sometime in the past and not in the future.
Filter bike_share_rides to get only the rides from the past or today, and save this as bike_share_rides_past.
Assert that the dates in bike_share_rides_past occurred only in the past.

Hands-on interactive exercise

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

library(lubridate)
# Convert date to Date type
bike_share_rides <- bike_share_rides %>%
  mutate(date = ___)

# Make sure all dates are in the past
___

# Filter for rides that occurred before or on today's date
bike_share_rides_past <- bike_share_rides %>%
  filter(___)

# Make sure all dates from bike_share_rides_past are in the past
___

Edit and Run Code

This exercise is part of the course

Cleaning Data in R

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.

Exercise 1: Data type constraints Exercise 2: Common data types Exercise 3: Converting data types Exercise 4: Trimming strings Exercise 5: Range constraints Exercise 6: Ride duration constraints Exercise 7: Back to the future

Current Exercise

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