Karin Lagesen wrote: > I am sorry if this is a faq or tutorial somewhere, but I am unable to > solve this one. > > What I am looking for is a count of how many different > categories(numbers in this case) that appears for a given factor. > > Example: > > >> l <- c("Yes", "No", "Perhaps") >> x <- factor( sample(l, 10, replace=T), levels=l ) >> m <- c(1:5) >> y <- factor( sample(m, 10, replace=T), levels=m ) >> z = c(1:10) >> my_df = data.frame("Z" = z, "Y"= y, "X" = x) >> my_df >> > Z Y X > 1 1 4 Yes > 2 2 1 No > 3 3 2 Perhaps > 4 4 3 Yes > 5 5 4 No > 6 6 5 No > 7 7 1 Yes > 8 8 4 Perhaps > 9 9 4 Yes > 10 10 2 Perhaps > > > I am now looking for a table that will give me this: > > Yes 3 # Yes has these ys: 4,3,1,4, two are the same, ergo 3 > No 3 # No has these ys: 1,4,5 > Perhaps 2 # Perhaps has these ys: 2,4,2 > Maybe: apply(table(my_df$X,my_df$Y),1,function(x) sum(x!=0))
domenico > My dataframe has lots of other colums too, but I only want this > information out. > > > Thankyou for your help! > > Karin > ______________________________________________ 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.