Hi Ragia, If you have read in your data frame with read.table or similar and not specified stringsAsFactors=FALSE, the two columns will already be factors. However, unless they both contain the same number of unique values, the numbers associated with those levels won't be the same. Probably the easiest way to get the same IDs for both is to read in the data with stringsAsFactors=FALSE and then convert the two columns:
url_levels<-unique(unlist(otf_data)) otf_data[,1]<-factor(otf_data[,1],levels=url_levels) otf_data[,2]<-factor(otf_data[,2],levels=url_levels) Jim On Wed, Mar 9, 2016 at 7:10 PM, Ragia . <ragi...@hotmail.com> wrote: > Dear group > kindly if i had data frame of 2 columns that has repeated URLS ..and want to > replace those urls with ID's for each one so the url will have > unique ID, how can I do this > thanks in advance > e.g otf data > > pcworld.com open.itworld.com > pcworld.com storage.itworld.com > salon.com images.salon.com > go.theregister.com theregister.co.uk > techchuck.com pcworld.com > ecoustics.com pcworld.com > > Ragia > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.