HI, Try this: set.seed(485) dat1<- as.data.frame(matrix(sample(0:10,26*10,replace=TRUE),ncol=26)) mean(dat1$V21[dat1$V2==1|dat1$V2==0]) #[1] 3.8 #or with(dat1,mean(V21[V2==1|V2==0])) #[1] 3.8
A.K. I have data in 26 columns, I'm trying to get a mean for column 21 only for the participants that are either 0 or 1 in column 2. One of the commands I tried looked something like this mean(data1$V21, if(V2 = 1)) So basically I need to have the program run a mean (and later other forms of analysis) on participants based on their condition. either 0 or 1. Help is greatly appreciated. Thanks ______________________________________________ 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.
