Hello, I tried for about three hours now to solve this problem but I can't figure it out. I am sure someone knows how do it. At least I hope so.
I have a data frame somewhat like this: myframe <- data.frame (ID=c("Ernie", "Ernie", "Bert", "Bert"), Timestamp=c("24.09.2012 09:00", "24.09.2012 09:00", "24.09.2012 10:00", "25.09.2012 10:00"), Hunger=c("1","5","2","2"), Temp=c("25","30","27","28") ) myframe As you can see for Ernie I do have different data for 24.09.2012 9:00. Now I would like to average the Hunger and Temp value for this timestamp to get a data frame without duplicated Times and the respective average Temp and Hunger. I tried something like Meanframe<- by(myframe[, 3:4], duplicated(myframe$ID, Zusatzdaten3$Timestamp) == TRUE, mean) but it doesn't work and I guess that it is also totally crap ;-) Tagmarie -- View this message in context: http://r.789695.n4.nabble.com/average-environmental-data-if-AnimalID-and-Time-is-duplicated-tp4644218.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.