R Programming By Example

Tracking state with symbols and variables

Like most programming languages, R lets you assign values to variables and refer to these objects by name. The names you use to refer to variables are called symbols in R. This allows you to keep some information available in case it's needed at a later point in time. These variables may contain any type of object available in R, even combinations of them when using lists, as we will see in a later section in this chapter. Furthermore, these objects are immutable, but that's a topic for Chapter 9, Implementing an Efficient Simple Moving Average.

In R, the assignment operator is <-, which is a less-than symbol (<) followed by a dash (-). If you have worked with algorithm pseudo code before, you may ...