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Calling R lovers to work together on “The R Programming wikibook”

74 points by TalGalili 15y ago

jergosh 15y ago
Even better, reimplement the interpreter with modern data structures...
- TalGalili 15y ago
  Go ahead... :)
- ahi 15y ago
  Didn't they try that once? And instead of fixing things they ended up with two sets of broken data structures? I could be mistaken.
- MaxMorlock 15y ago
  Would you please be so kind and explain in some more detail what you mean? Thank you!
  - jergosh 15y ago
    Well, as far as I remember lists (which are used like hash tables, as they associate variables with names, see http://cran.r-project.org/doc/manuals/R-lang.html#List-objects http://cran.r-project.org/doc/manuals/R-lang.html#List-objec...), implement indexing as an O(n) operation. Only after they reach a certain size are they converted to a hash table. 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.
- mjw 15y ago
  Glad I'm not the only one bugged by this. Next time I think I might try the http://rubyforge.org/projects/rsruby/ http://rubyforge.org/projects/rsruby/ bindings instead.
  - jergosh 15y ago
    I would recommend http://rpy.sourceforge.net/rpy2.html http://rpy.sourceforge.net/rpy2.html (I'm biased, though ;))
- klipt 15y ago
  Even better, write a statistical module for scipy that's competitive with R.
mjw 15y ago
I'd love to see an "R for rubyists/pythonists/...", basically an R tutorial aimed at reasonably experienced programmers which explains what you need to know about the quirks of R to properly grok it as a language, how it differs to ones you're familiar with, etc. 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.
- ahi 15y ago
  Not sure that's possible. "R in a Nutshell" is 640 pages for a reason.
- noahnoahnoah 15y ago
  I've always found this to be helpful for programmers coming from other languages: http://www.johndcook.com/R_language_for_programmers.html http://www.johndcook.com/R_language_for_programmers.html (not the author, just a fan)

74 points by TalGalili 15y ago

jergosh 15y ago

Even better, reimplement the interpreter with modern data structures...

TalGalili 15y ago
Go ahead... :)
ahi 15y ago
Didn't they try that once? And instead of fixing things they ended up with two sets of broken data structures? I could be mistaken.
MaxMorlock 15y ago
Would you please be so kind and explain in some more detail what you mean? Thank you!
- jergosh 15y ago
  Well, as far as I remember lists (which are used like hash tables, as they associate variables with names, see http://cran.r-project.org/doc/manuals/R-lang.html#List-objects http://cran.r-project.org/doc/manuals/R-lang.html#List-objec...), implement indexing as an O(n) operation. Only after they reach a certain size are they converted to a hash table. 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.
mjw 15y ago
Glad I'm not the only one bugged by this. Next time I think I might try the http://rubyforge.org/projects/rsruby/ http://rubyforge.org/projects/rsruby/ bindings instead.
- jergosh 15y ago
  I would recommend http://rpy.sourceforge.net/rpy2.html http://rpy.sourceforge.net/rpy2.html (I'm biased, though ;))
klipt 15y ago
Even better, write a statistical module for scipy that's competitive with R.

mjw 15y ago

I'd love to see an "R for rubyists/pythonists/...", basically an R tutorial aimed at reasonably experienced programmers which explains what you need to know about the quirks of R to properly grok it as a language, how it differs to ones you're familiar with, etc. 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.

ahi 15y ago
Not sure that's possible. "R in a Nutshell" is 640 pages for a reason.
noahnoahnoah 15y ago
I've always found this to be helpful for programmers coming from other languages: http://www.johndcook.com/R_language_for_programmers.html http://www.johndcook.com/R_language_for_programmers.html (not the author, just a fan)