Dear R ExpeRts, I'm having memory difficulties using mahalanobis distance to trying to cluster in R. I was wondering if anyone has done it with a matrix of 6525x17 (or something similar to that size). I have a matrix of 6525 genes and 17 samples. I have my R memory increased to the max and am still getting "cannot allocate vector of size" errors. My matrix "x" is actually a transpose of the original matrix (as I want to cluster by samples and not genes). "y" is a vector of the mean gene expression levels and "z" is the covariance matrix of "x" (I think this is where the problem lies as the covariance matrix is enormous.
I can't really provide a reproducible example as I would have to attach my data files, which I don't think anyone would appreciate. rm(list=ls()) #removes everything from memory# gc() #collects garbage# memory.limit(size = 4095) #increases memory limit# x <- as.matrix(read.table("x.txt", header=TRUE, row.names=1)) y <- as.matrix(read.table("y.txt", header=TRUE, row.names=1)) z <- as.matrix(read.table("z.txt", header=TRUE, row.names=1)) mal <- mahalanobis(x, y, z) The ultimate goal is to run "hclust" with the mahalanobis distance matrix. If anyone knows where I could find a more "memory friendly" function or any advise as to what I might try to optimize my code, I would appreciate it. sessionInfo() is below. Many Thanks, _____________________________________________ Patrick Richardson Biostatistician - Program of Translational Medicine Van Andel Research Institute - Webb Lab 333 Bostwick Avenue NE Grand Rapids, MI 49503 R version 2.8.0 (2008-10-20) i386-pc-mingw32 locale: LC_COLLATE=English_United States.1252;LC_CTYPE=English_United States.1252;LC_MONETARY=English_United States.1252;LC_NUMERIC=C;LC_TIME=English_United States.1252 attached base packages: [1] stats graphics grDevices datasets tcltk utils methods base other attached packages: [1] svSocket_0.9-5 svIO_0.9-5 R2HTML_1.59 svMisc_0.9-5 svIDE_0.9-5 loaded via a namespace (and not attached): [1] tools_2.8.0 This email message, including any attachments, is for th...{{dropped:9}} ______________________________________________ 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.