Dear R users, I have a matrix a and a classification vector b such that
> str(a) num [1:50, 1:800000] and > str(b) Factor w/ 3 levels "cond1","cond2","cond3" I'd like to do an anova on all 800000 columns and record the F statistic for each test; I currently do this using f.stat.vec <- numeric(length(a[1,]) for (i in 1:length(a[1,]) { f.test.frame <- data.frame(nums = a[,i], cond = b) aov.vox <- aov(nums ~ cond, data = f.test.frame) f.stat <- summary(aov.vox)[[1]][1,4] f.stat.vec[i] <- f.stat } The problem is that this code takes about 70 minutes to run. Is there a faster way to do an anova & record the F stat for each column? Any help would be appreciated. Thanks Heath [[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.