Hi, Try: df2 <- df df2[] <- lapply(df2,function(x) as.character(as.numeric(factor(x,levels=unique(df$G1)))))
A.K. On Sunday, April 13, 2014 3:36 PM, Sergio.pv <serpalm...@gmail.com> wrote: I have a data.frame of two vectors. df <- data.frame(G1=c("b","a","e","d","c"), G2=c("c","d","e","b","a")) You can see that both vectors have the same characters, but in diferent order. I want to convert them into numbers and then compare them. To compare G2 to G1, G1 must be the reference, so the output will be this: df2 <- data.frame(G1=c("1","2","3","4","5"), G2=c("5","4","3","1","2")) Is there a way to do this?, thanks -- View this message in context: http://r.789695.n4.nabble.com/Transform-characters-to-numbers-and-compare-tp4688708.html Sent from the datatable-help mailing list archive at Nabble.com. _______________________________________________ datatable-help mailing list datatable-h...@lists.r-forge.r-project.org https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/datatable-help ______________________________________________ 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.