Subject: Re: performance of apply From: Peter Dalgaard BSA <p.dalgaard@biostat.ku.dk> Date: 29 May 1998 18:04:30 +0200 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Oh, dear. Looking at apply, we have right in the middle of it: for (i in 1:d2) ans[[i]] <- FUN(array(newX[, i], d.call, dn.call), ...) Assignment to the tail of a very long list... I think I'm beginning to understand why Ross keeps talking about generic vectors. Either that or we need to add some low-level list primitives to the language. Got it in one. To reach ans[[i]] you have to cdr down the whole list. The subsetting code would be vastly simplified without the special list code. Ugliest of all is subscript manipulation for lists with dim attributes. [ I estimate 2 months for a fix - not that it will take that long, but there are some other things higher up the todo list ]. Ross -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-devel-request@stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._
performance of apply
1 message · Ross Ihaka