hi guys, many many thanks for all the solutions! :-D they are working great! i have another "little" question: i would like to save these groups in a new column with serial number like the solution from David, but wit integer values: 1,2,3... i do this allready but with my 1. solution and there is to much temp-data, that i dont realy nead ... if you have any idea, that'll be really great!
thanks a lot ! -- View this message in context: http://r.789695.n4.nabble.com/group-by-in-data-frame-tp3324240p3325199.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.
