Thanks Duncan. This is a package, SIAR.
> fo <- ordered(f) > fo [1] a b c d e Levels: a < b < c < d < e > max(fo) [1] e Levels: a < b < c < d < e The data set has 101 values, what can I use instead of letters? Best wishes, Alex. -- View this message in context: http://r.789695.n4.nabble.com/Error-in-Summary-factor-c-1L-1L-1L-1L-1L-1L-1L-1L-1L-1L-4L-max-not-meaningful-for-factors-tp4022502p4023231.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.