[Rd] data frame subset patch, take 2

Vladimir Dergachev vdergachev at rcgardis.com
Wed Dec 13 20:11:00 CET 2006


On Wednesday 13 December 2006 1:23 pm, Marcus G. Daniels wrote:
> Vladimir Dergachev wrote:
> >     2. It would be nice to have true hashed arrays in R (i.e. O(1) access
> > times). So far I have used named lists for this, but they are O(n):
>
> new.env(hash=TRUE) with get/assign/exists works ok.  But I suspect its
> just too easy to use named lists because it is easy, and that has bad
> performance ramifications for user code (perhaps the R developers are
> more vigilant about this for the R code itself).

Cool, thank you ! 

I wonder whether environments could be extended to allow names() to work 
(altough I see that ls() does the same function) and to allow for(i in E) 
loops.

                       thank you

                               Vladimir Dergachev



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