Getting datetimes into R
Just like dates without times, if you want R to recognize a string as a datetime you need to convert it, although now you use
as.POSIXct()
. as.POSIXct()
expects strings to be in the format YYYY-MM-DD HH:MM:SS
.
The only tricky thing is that times will be interpreted in local time based on your machine's set up. You can check your timezone with Sys.timezone()
. If you want the time to be interpreted in a different timezone, you just set the tz
argument of as.POSIXct()
. You'll learn more about time zones in Chapter 4.
In this exercise you'll input a couple of datetimes by hand and then see that read_csv()
also handles datetimes automatically in a lot of cases.
This exercise is part of the course
Working with Dates and Times in R
Exercise instructions
- Use
as.POSIXct()
and an appropriate string to input the datetime corresponding to Oct 1st 2010 at 12:12:00. - Enter the same datetime again, but now specify the timezone as
"America/Los_Angeles"
. - Use
read_csv()
to read inrversions.csv
again. - Examine the structure of the
datetime
column to verifyread_csv()
has correctly interpreted it as a datetime.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# Use as.POSIXct to enter the datetime
as.POSIXct(___)
# Use as.POSIXct again but set the timezone to `"America/Los_Angeles"`
as.POSIXct(___, tz = ___)
# Use read_csv to import rversions.csv
releases <- read_csv(___)
# Examine structure of datetime column
str(___)