Dear Dennis and Peter, Thank you for the suggestions - they work very well with my example data.
I *think* I've got it up and running using my real data (with 2000 columns) too, with: sprintf("%s%04d", "X", c(1:2000)) then the stacking/unstacking operations. Thanks again for the help Best wishes, Matthew -----Original Message----- From: Peter Ehlers [mailto:ehl...@ucalgary.ca] Sent: 12 March 2011 11:09 AM To: Dennis Murphy Cc: Matthew Carroll; r-help@r-project.org Subject: Re: [R] Column order in stacking/unstacking On 2011-03-12 02:01, Dennis Murphy wrote: > Hi: > > It would help if you named your variables such that alphanumeric ordering > doesn't disturb your variable ordering. Having been burned by this a few > times, I've learned the basics of sprintf() :) Here's your example > revisited, along with an alternative stacking/unstacking display with > package reshape. > > library(reshape) > vnames<- paste('X', sprintf('%02d', c(1, 2, 10)), sep = '') >> vnames > [1] "X01" "X02" "X10" <snip> You can do this a bit more simply with sprintf: vnames <- sprintf("%s%02d", "X", c(1, 2, 10)) Peter Ehlers ______________________________________________ R-help@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.