In this chapter, we leave data analysis and return to programming and software development, topics that are the focus of the remaining chapters of the book. Chapter 1 gave a tutorial introduction to R programming but left out a lot of details. This chapter covers many of those details while the next two chapters will cover more advanced aspects of R programming: functional programming and object oriented programming.
Expressions
We begin the chapter by going back to expressions. Everything we do in R involves evaluating expressions. Most expressions we evaluate to do a computation and get the result, ...
