Hi all Sometime ago I asked for a solution about how to aggregate data and the help was wonderful. Now, I´d like to know how to extract for each individual case below the first and the last observation to obtain this:
ind y 1 8 1 9 2 7 2 11 3 9 3 10 4 8 4 5 # Below the example: ind <- c(1,1,1,2,2,3,3,3,4,4,4,4) y <- c(8,10,9,7,11,9,9,10,8,7,6,5) dat <- as.data.frame(cbind(ind,y)) dat attach(dat) mean.ind <- aggregate(dat$y, by=list(dat$ind), mean) mean.ind Thanks Mauricio ______________________________________________ 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.
