Jim, > Does this do what you want? It creates a new dataframe with those > 'mg' that have at least a certain number of observation.
Looks good. I also have an alternative solution which appears to work, so I'll see which is quicker on the big data set in question. My solution: mgsize <- as.data.frame(table(in$mg)) in2 <- merge(in,mgsize,by.x="mg",by.y="Var1") out <- subset(in2, Freq > 1, select= -Freq) Thanks for your help. Ron. ______________________________________________ R-help@stat.math.ethz.ch 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.
