Hello, I have little doubt, and I do not think that the way I solve the problem is the best way to do it. The following is a small dataset
x<-data.frame(city="Barcelona",sales=253639) x<-rbind(x,data.frame(city="Madrid",sales=223455)) x<-rbind(x,data.frame(city="Lisbon",sales=273633)) x<-rbind(x,data.frame(city="Madrid",sales=266535)) x<-rbind(x,data.frame(city="Barcelona",sales=258369)) x<-rbind(x,data.frame(city="Lisbon",sales=273633)) x<-rbind(x,data.frame(city="Barcelona",sales=22579)) x<-rbind(x,data.frame(city="Lisbon",sales=26333)) x<-rbind(x,data.frame(city="Barcelona",sales=253639)) x$num<-as.numeric(as.numeric(factor(x$city))) View(x) my problem and my doubts start here, I'm trying to create a list of cities and the code that was assigned in. x$num<-as.numeric(as.numeric(factor(x$city))) here seems to work fine, but the largest dataset repeats some values and hiding others, this is the correct way to present unique values in a column, and view the contents with other columns rescity<-x[unique(x$city),c(3,1)] rescity Thanks -- View this message in context: http://r.789695.n4.nabble.com/Unique-in-DataFrame-tp4488943p4488943.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.