> * R. Michael Weylandt <zvpunry.jrlyn...@tznvy.pbz> [2012-10-16 16:19:27 > +0100]: > > Have you looked at using table() directly? If I understand what you > want correctly something like: > > table(do.call(paste, x))
I wished to avoid paste (I will have to re-split later, so it will be a performance nightmare). > Also, if you take a look at the development version of R, changes are > being put in place to allow much larger data sets. >> >> xtabs(), although dog slow, would have footed the bill nicely: >> --8<---------------cut here---------------start------------->8--- >>> x <- data.frame(a=1:32,b=1:32,c=1:32,d=1:32,e=1:32) >>> system.time(subset(as.data.frame(xtabs( ~. , x )), Freq != 0 )) >> user system elapsed >> 12.788 4.288 17.224 >> --8<---------------cut here---------------end--------------->8--- you should not need "much larger data sets" for this. x is sorted. -- Sam Steingold (http://sds.podval.org/) on Ubuntu 12.04 (precise) X 11.0.11103000 http://www.childpsy.net/ http://openvotingconsortium.org http://iris.org.il http://www.memritv.org http://memri.org http://think-israel.org Just because you're paranoid doesn't mean they AREN'T after you. ______________________________________________ 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.
