Hi Muhammad, Load the data from all of the files into an array (probably using a for loop), then call apply on the resulting array: ie
## replace the first line with code to load your data > rr <- array(c(rep(1:3,3), rep(4:6,3), rep(7:9,3)), c(3,3,3)) > apply(rr, c(1,2), sd) [,1] [,2] [,3] [1,] 3 3 3 [2,] 3 3 3 [3,] 3 3 3 --Gray On Fri, Dec 4, 2009 at 11:56 AM, Muhammad Rahiz <muhammad.ra...@ouce.ox.ac.uk> wrote: > Hello R-users, > > I would like to know how to find the standard deviation for each element in > a set of matrices. > > Given the following files, > > File1 File2 File3 > 1 1 1 4 4 4 7 7 7 > 2 2 2 5 5 5 8 8 8 > 3 3 3 6 6 6 9 9 9 > > I want to calculate the standard deviation for every cell in the file (I'm > using gridded data). The desired output is > > Output > 3 3 3 > 3 3 3 > 3 3 3 > > > Thanks. > > Muhammad > > -- > Muhammad Rahiz | Doctoral Student in Regional Climate Modeling > > Climate Research Laboratory, School of Geography & the Environment > Oxford University Centre for the Environment > South Parks Road, Oxford, OX1 3QY, United Kingdom Tel: +44 (0)1865-285194 > Mobile: +44 (0)7854-625974 > Email: muhammad.ra...@ouce.ox.ac.uk > > ______________________________________________ > 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. > -- Gray Calhoun Assistant Professor of Economics Iowa State University ______________________________________________ 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.