Part 5. Expanding your skills

In this final section, we consider advanced topics that will enhance your skills as an R programmer. Chapter 19 completes our discussion of graphics with a presentation of one of R’s most powerful approaches to visualizing data. Based on a comprehensive grammar of graphics, the ggplot2 package provides a set of tools that allow you visualize complex data sets in new and creative ways. You’ll be able to easily create attractive and informative graphs that would be difficult or impossible to create using R’s base graphics system.

Chapter 20 provides a review of the R language at a deeper level. This includes a discussion of R’s object-oriented programming features, working with environments, and advanced function writing. Tips for writing efficient code and debugging programs are also described. Although chapter 20 is more technical than the other chapters in this book, it provides extensive practical advice for developing more useful programs.

Throughout this book, you’ve used packages to get work done. In chapter 21, you’ll learn to write your own packages. This can help you organize and document your work, create more complex and comprehensive software solutions, and share your creations with others. Sharing a useful package of functions with others can also be a wonderful way to give back to the R community (while spreading your fame far and wide).