If you didn't specify an external BLAS when you ran R configure script, you are not using ATLAS. If you're not sure and you still have the output of the configure script, at the end it'll say whether it uses an external BLAS.
Alternatively, you may also want to generate two random 5000x5000 matrices and do their multiplication a = matrix(rnorm(5000*5000), 5000, 5000) b = matrix(rnorm(5000*5000), 5000, 5000) c = a%*%b While the calculation is running, in a separate terminal, run top and watch how much CPU R takes. AFAIK standard installation of R is single threaded and will only use one CPU (up to 100%). ATLAS is multithreaded and (unless you configured it otherwise) it will use all available processors, so if you have a 4-core machine, you will see CPU usage of nearly 400%. Note though that this will not discriminate ATLAS from other multi-threaded BLASes. HTH, Peter On Wed, May 26, 2010 at 2:16 PM, Jonathan Greenberg <greenb...@ucdavis.edu> wrote: > Rhelpers: > > I recently installed the 64-bit version of R on my Debian system, and > afterwards was asked if it was compiled using ATLAS. Is there a way > to test to see if R is using ATLAS? > > --j > > ______________________________________________ > 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.
