Combine the two matrices into one data.frame and order them Example done using data.frames rather than matrices but just use use data.frame(x,y) to convert to a data.frame
bmat <- data.frame(matrix(1:25,5)) smat <- data.frame(aa= LETTERS[1:25], bb = rep(c("a","b","c", "d", "e"),5)) df1 <- data.frame(smat, bmat) orddata <- df1[order(df1[,2],decreasing=TRUE),] I hope this helps. --- On Sun, 6/26/11, Aparna Sampath <aparna.sampat...@gmail.com> wrote: > From: Aparna Sampath <aparna.sampat...@gmail.com> > Subject: [R] Ordering a matrix based on cluster no > To: r-help@r-project.org > Received: Sunday, June 26, 2011, 9:42 AM > Hi All > > I have a symmetric matrix of genes ( 100x100 matrix). I > also have a matrix > (100x2) of two columns where column 1 has the gene names > and column 2 has > the cluster it belongs to (they are sorted and grouped > based on the cluster > no). > > I would like to order the rows and columns of the 100x 100 > matrix such that > the first n genes correspond to cluster 1 and next n genes > correspond to > cluster 2 and so on. The order of genes is taken from the > sorted > matrix(100x2). > > Can someone tell me how to do this in R. > > I tried the grep() but I get a message saying that the > length of pattern >1 > so only first element will be compared. But i want to check > for each gene in > the 100x100 matrix for its cluster number and then group > it. > > I also tried the order() but it did not help either. > > Thanks for the help! :) > > Aparna > > -- > Aparna Sampath > Master of Science (Bioinformatics) > Nanyang Technological University > Mob no : +65 91601854 > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. > ______________________________________________ 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.