R Programming Fundamentals

Lists

A list is different from a vector because it can hold many different types of R objects inside it, including other lists. If you have experience programming in another language, you may be familiar with lists, but if not, don't worry! You can create a list in R using the list() function, as shown in the following example:

L1 <- list(1, "2", "Hello", "cat", 12, list(1, 2, 3))

Let's walk through the elements of this list. First, we have the number 1. Then, a character string, "2", followed by the character string "Hello", the character string "cat", the number 12, and then a nested list, which contains the numbers 1, 2, and 3.

Accessing these different parts of the list that we just created is slightly different—now, you are using list ...