olddata$first <- as.numeric(! duplicated(olddata$ID))
:-) > On Nov 30, 2024, at 22:27, Sorkin, John <jsor...@som.umaryland.edu> wrote: > > ID <- c(rep(1,10),rep(2,6),rep(3,2)) > date <- c(rep(1,2),rep(2,2),rep(3,2),rep(4,2),rep(5,2), > rep(5,3),rep(6,3),rep(10,2)) > olddata <- data.frame(ID=ID,date=date) > class(olddata) ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide https://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
