R in a Nutshell, 2nd Edition

Objects

All R code manipulates objects. The simplest way to think about an object is as a “thing” that is represented by the computer. Examples of objects in R include numeric vectors, character vectors, lists, and functions. Here are some examples of objects:

> # a numerical vector (with five elements)
> c(1,2,3,4,5)
[1] 1 2 3 4 5

> # a character vector (with one element)
> "This is an object too"
[1] "This is an object too"

> # a list
> list(c(1,2,3,4,5),"This is an object too", " this whole thing is a list")
[[1]]
[1] 1 2 3 4 5

[[2]]
[1] "This is an object too"

[[3]]
[1] " this whole thing is a list"

> # a function
> function(x,y) {x + y}
function(x,y) {x + y}