Hands-On Programming with R

Chapter 3. R Objects

In this chapter, you’ll use R to assemble a deck of 52 playing cards.

You’ll start by building simple R objects that represent playing cards and then work your way up to a full-blown table of data. In short, you’ll build the equivalent of an Excel spreadsheet from scratch. When you are finished, your deck of cards will look something like this:

 face   suit value
 king spades    13
queen spades    12
 jack spades    11
  ten spades    10
 nine spades     9
eight spades     8
...

Do you need to build a data set from scratch to use it in R? Not at all. You can load most data sets into R with one simple step, see “Loading Data”. But this exercise will teach you how R stores data, and how you can assemble—or disassemble—your own data sets. You will also learn about the various types of objects available for you to use in R (not all R objects are the same!). Consider this exercise a rite of passage; by doing it, you will become an expert on storing data in R.

We’ll start with the very basics. The most simple type of object in R is an atomic vector. Atomic vectors are not nuclear powered, but they are very simple and they do show up everywhere. If you look closely enough, you’ll see that most structures in R are built from atomic vectors.

Atomic Vectors

An atomic vector is just a simple vector of data. In fact, you’ve already made an atomic vector, your die object from Part I. You can make an atomic vector by grouping some values of data together with c:

die <- c(1, 2, 3, 4, 5, 6)
die