This is a bug, which I've fixed in the development version (hopefully to be released next week). In the plyr 1.2:
OK, thank you both for your answers. I'll wait for the next version. Regards, Jan ______________________________________________ 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.