Calling R lovers to work together on “The R Programming wikibook”
r-statistics.com
r-statistics.com
As opposed to a tutorial aimed at the "I really just want a recipe to achieve statistical task xyz" crowd.
In particular: every time I delve back into R, I forget how its funky data structures work.
(not the author, just a fan)
Next time I think I might try the http://rubyforge.org/projects/rsruby/ bindings instead.
Everything is pass by value with some cases being marked as 'safe', i. e. if you know beforehand the variable won't be changed it's not copied to save time.
The reason for this is that the project was designed by people who were primarily statisticians, and the most glaring performance problems were later fixed by hacks and 'special cases'.
Disclaimer: Most of this I know second hand from a coworker who's an author of many R packages. I worked with R's interface to C and it wasn't a pleasant experience.