Combining i, j, and by (I)

In this exercise, you will combine the i, j, and by arguments to find the first and last ride for each start station. Recall that data.table first filters the rows in i, and then groups the rows using by, and finally compute the expression in j.

This exercise is part of the course

Data Manipulation with data.table in R

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Exercise instructions

Arrange batrips using the start_date column in ascending order.
Group the rows by start_station.
Extract the first and last rows of start_date.

Hands-on interactive exercise

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

# Find the first and last ride for each start_station
first_last <- batrips[___, 
                      .(start_date = ___), 
                      by = ___]
first_last

Edit and Run Code