The R-language is mostly defined in terms of how GNU-R works. While there is the R language definition, it is informal and incomplete. The distinction between R-language and GNU-R is a bit murky because the R-language is not formally defined. I’ll call that implementation GNU-R to distinguish it from R-language, and from the other implementations I’ll discuss later in the chapter. The most popular implementation is the one from. The implementation is concrete: it reads R code and computes a result. The R-language is abstract: it defines what R code means and how it should work. To understand R’s performance, it helps to think about R as both a language and as an implementation of that language. Let’s get started by learning more about why R is slow. In R’s C interface, you’ll learn a little about R’s C internals. To really understand the performance of built-in base functions, you’ll need to learn a little bit about R’s C API. Rcpp will teach you the absolute minimum you need to know about C++ so you can write fast code using the Rcpp package. In Memory, you’ll learn about how R uses memory, and how garbage collection and copy-on-modify affect performance and memory usage.įor really high-performance code, you can move outside of R and use another programming language. First you figure what’s slow, and then you apply some general techniques to make the slow parts faster. In Profiling, you’ll learn how to systematically make your code faster. The following four chapters will give you the skills to improve the speed of your code when you need to: In this chapter, you’ll learn about some of the trade-offs that R has made, valuing flexibility over performance. The goal of this part of the book is to give you a deeper understanding of R’s performance characteristics. While R is slow compared to other programming languages, for most purposes, it’s fast enough. It was not designed to make life easier for your computer. R was purposely designed to make data analysis and statistics easier for you to do. You’re reading the first edition of Advanced R for the latest version see the second edition.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |