Folks, I have a 3000 x 4 matrix (y), which I need to regress row-by-row against a 4-vector (x) to create a matrix lm.y of intercepts and slopes. To illustrate:
y <- matrix(rnorm(12000), ncol = 4) x <- c(1/12, 3/12, 6/12, 1) system.time(lm.y <- t(apply(y, 1, function(z) lm(z ~ x)$coefficient))) [1] 44.72 18.00 69.52 NA NA Takes more than a minute to do (and I need to do many similar regressions a day). Is there a more efficient way of handling this? I'm running R 2.4.1 on Windows XP Service Pack 2 on a Intel Xeon dual-core 2.66GHz with 3GB RAM. Thanks very much, Murali --------------------------------------------------------------------------- This message (including any attachments) is confidential and...{{dropped}} ______________________________________________ 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.