Computing in j (II)
In the last exercise, you performed computations in j
which returned only a single value, a vector of length one. However, you often perform computations which return more than one value. The good news is that the syntax for these calculations is still the same!
You will use the difftime()
function in this exercise to calculate the difference in minutes between the trips. difftime()
needs two required arguments, time1
and time2
to calculate the difference (time1 - time2
). To calculate the difference in minutes, set the units
argument to "min"
:
date1 <- "2018-12-20 11:30:00 EST"
date2 <- "2018-12-20 11:20:00 EST"
difftime(date1, date2, units = "min")
Time difference of 10 mins
This exercise is part of the course
Data Manipulation with data.table in R
Exercise instructions
Calculate the difference in minutes between end_date
and start_date
.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# Compute duration of all trips
trip_duration <- batrips[, difftime(___)]
head(trip_duration)