From: Jim Lemon <jim_at_bitwrit.com.au>

Date: Wed, 09 Jul 2008 20:33:39 +1000

R-help_at_r-project.org mailing list

https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. Received on Wed 09 Jul 2008 - 10:57:56 GMT

Date: Wed, 09 Jul 2008 20:33:39 +1000

On Wed, 2008-07-09 at 11:40 +0200, Anne-Marie Ternes wrote:

*> Hi,
**>
*

> if given the value of, say, 15000, I would like to be able to divide

*> that value recursively by, say, 5, and to get a vector of a determined
**> length, say 9, the last value being (set to) zero- i.e. like this:
**>
**> 15000 3000 600 120 24 4.8 0.96 0.192 0
**>
**> These are in fact concentration values from an experiment. For my
**> script, I get only the starting value (here 15000), and the factor by
**> which concentration is divided for each well, the last one having, by
**> definition, no antagonist at all.
**>
**> I have tried to use "seq", but it can "only" do positive or negative
**> increment. I didn't either find a way with "rep", "sweep" etc. These
**> function normally start from an existing vector, which is not the case
**> here, I have only got a single value to start with.
**>
**> I suppose I could do something "loopy", but I'm sure there is a better
**> way to do it.
**>
*

Well, if you really want to do it recursively (and maybe loopy as well)

recursivdiv<-function(x,denom,lendiv,firstpass=TRUE) {
if(firstpass) lendiv<-lendiv-1

if(lendiv > 1) {

divvec<-c(x/denom,recursivdiv(x/denom,denom,lendiv-1,FALSE))
cat(divvec,ndiv,"\n")

}

else divvec<-0

if(firstpass) divvec<-c(x,divvec)

return(divvec)

}

Jim

R-help_at_r-project.org mailing list

https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. Received on Wed 09 Jul 2008 - 10:57:56 GMT

Archive maintained by Robert King, hosted by
the discipline of
statistics at the
University of Newcastle,
Australia.

Archive generated by hypermail 2.2.0, at Wed 09 Jul 2008 - 12:31:08 GMT.

*
Mailing list information is available at https://stat.ethz.ch/mailman/listinfo/r-help.
Please read the posting
guide before posting to the list.
*