by Hadley Wickham
http://adv-r.had.co.nz/
Hadley brings an in-depth analysis of the R statistical language in this book and opens up more questions as it enlightens the reader to possibilities with R.
This book is only for the nerds of the nerds as it explores the R programming language, a language used mainly by non-programmers for statistical analysis. As such, the readership for this book is presumably small. Nonetheless, it fills a need as it supplies R users with a textbook for advanced programming.
R is a functional programming language, which means that functions can be passed as arguments in calls to other functions. Hadley shows us, as only a true scientist can, how to take full advantage of this property. He also explores R’s underpinnings (R written to implement R functions); R’s foundation in another programming language, C; and R’s extensions into C++, a third programming language. All this in the name of making R more usable and have better performance.