library(zoo) library(chron) t1 <- chron("1/1/2006", "00:00:00") t2 <- chron("1/31/2006", "23:45:00") deltat <- times("00:15:00") tt <- seq(t1, t2, by = times("00:15:00")) d <- sample(33:700, 2976, replace=TRUE) sin.zoo <- zoo(d,tt)
#there are ninety six reading in a day d.max <- rollapply(sin.zoo, width=96, FUN=max) d.min <- rollapply(sin.zoo, width=96, FUN=max) this is about what I would like to do. I want to be able to get the max for one day and then also get the index that coincides with this max time period. Also, the same thing with the min. With the real data I am trying to find out at what time the maximum dissolved oxygen value is for each day. Thanks -- Stephen Sefick Research Scientist Southeastern Natural Sciences Academy Let's not spend our time and resources thinking about things that are so little or so large that all they really do for us is puff us up and make us feel like gods. We are mammals, and have not exhausted the annoying little problems of being mammals. -K. Mullis ______________________________________________ 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.