Dear R users, I have 32 observations in data x. After sorting this, I want to compute means and variances of 3 groups divided by "nr".
Actually, the number of groups is flexible. Any suggestion will be greatly appreciated. Kathryn Lord --------------------------------------------------------------------------- x=rnorm(32) y=sort(x) nr=matrix(c(12,11,10,10,10,11),2,3) > nr [,1] [,2] [,3] [1,] 12 10 10 -> sum=32 [2,] 11 10 11 -> sum=32 For the 1st row in "nr", index of y = (1,..,12, 13,...,23, 24,...32) I want to compute means and variances for 3 groups (1st group is 1 through 12; 2nd group is 13-23; 3rd group is 24-32) For the 2nd row in "nr", index of y = (1,..,11, 12,...,22, 23,...32) also, I want to compute means and variances for 3 groups (1st group is 1 through 11; 2nd group is 12-22; 3rd group is 23-32) -- View this message in context: http://www.nabble.com/means-and-variances-of-several-groups-in-the-matrix-tp16803939p16803939.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.