would this work (shorter)? apply(a, 1, function(x) x[order(x)[2]])
On Tue, Apr 26, 2011 at 5:31 PM, Lars Bishop <lars...@gmail.com> wrote: > Hi, > > I need to extract the second largest element from each row of a > matrix. Below is my solution, but I think there should be a more efficient > way to accomplish the same, or not? > > > set.seed(1) > a <- matrix(rnorm(9), 3 ,3) > sec.large <- as.vector(apply(a, 1, order, decreasing=T)[2,]) > ans <- sapply(1:length(sec.large), function(i) a[i, sec.large[i]]) > ans > > Thanks in advance for your help, > Lars. > > [[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.
