Hello there, I'm still struggling with the *apply commands. I have 5 people with id's from 10 to 14. I have varying amounts (nrep) of repeated outcome (value) measured on them.
nrep <- 1:5 id <- rep(c("p1", "p2", "p3", "p4", "p5"), nrep) value <- rnorm(length(id)) I want to create a new vector that contains the sum of the values per person. subject.value[1] <- value[1] # 1 measurement subject.value[2] <- sum(value[2:3]) # the next 2 measurements ... subject.value[5] <- sum(value[11:15]) # the next 5 measurements I'd imagine it'll be some sort of *apply(value, nrep, sum) but I can't seem to land on the right format. Can someone give me a heads up as to what the correct syntax and function is? Danke, Robin Jeffries MS, DrPH Candidate Department of Biostatistics UCLA 530-624-0428 [[alternative HTML version deleted]] ______________________________________________ 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.