FES 720 Introduction to R

LAB: Dates and Times

This is the lab associated with the lesson on Dates and Times in R.

Please upload your final completed lab on the Assignments page in Canvas, as per the instructions below.

You are welcome and expected to ask for help from the instructors if you get stuck: Please also come to the R Bootcamp on Friday—there is coffee and snacks!

We will use the Harry Potter movie data again.

First, read in the Harry Potter data from the course website, using the following code. This will download and make the data available to you in your current R session.

# Read in the Harry Potter Movies Table 1
dat.hp <- read.table("http://www.simonqueenborough.info/R/data/harry-potter-movies.txt", sep = '\t', header = TRUE)

Table 1. Box office history for all Harry Potter movies.

Release Date Movie Production Budget Domestic Opening Weekend Domestic Box Office Worldwide Box Office
Nov 16, 2001 Harry Potter and the Sorcerer’s Stone $125,000,000 $90,294,621 $317,575,550 $974,755,371
Nov 15, 2002 Harry Potter and the Chamber of Secrets $100,000,000 $88,357,488 $261,987,880 $878,979,634
Jun 4, 2004 Harry Potter and the Prisoner of Azkaban $130,000,000 $93,687,367 $249,538,952 $796,688,549
Nov 18, 2005 Harry Potter and the Goblet of Fire $150,000,000 $102,685,961 $290,013,036 $896,911,078
Jul 11, 2007 Harry Potter and the Order of the Phoenix $150,000,000 $77,108,414 $292,004,738 $942,943,935
Jul 15, 2009 Harry Potter and the Half-Blood Prince $250,000,000 $77,835,727 $301,959,197 $935,083,686
Nov 19, 2010 Harry Potter and the Deathly Hallows: Part I $125,000,000 $125,017,372 $295,983,305 $960,283,305
Jul 15, 2011 Harry Potter and the Deathly Hallows: Part II $125,000,000 $169,189,427 $381,011,219 $1,341,511,219
Nov 18, 2016 Fantastic Beasts and Where to Find Them $180,000,000 $74,403,387 $234,037,575 $803,798,342


  1. What class is the Release Date column?

  2. Convert this column to a date.

  3. Extract the months from this new vector.

  4. On which weekday was each movie released?

  5. Which quarter (i.e., first quarter = Jan–Mar) was each movie released in?

How to write up your answers

Please check the help page for a reminder, if you need to.