Thanks a lot. I finally used M2 <- M M2[M < thresh] <- 0 M2[M >= thresh] <- 1
as I noticed that this one line M2 <- as.numeric( M[] < thresh ) vectorizes my matrix. One more question I have two matrices that only differ slightly. What will be the easiest way to compare and find the cells that are not the same? Best Regards Alex --- On Fri, 4/29/11, David Winsemius <dwinsem...@comcast.net> wrote: > From: David Winsemius <dwinsem...@comcast.net> > Subject: Re: [R] threshold matrix > To: "Alaios" <ala...@yahoo.com> > Cc: R-help@r-project.org > Date: Friday, April 29, 2011, 2:57 PM > > On Apr 29, 2011, at 9:37 AM, Alaios wrote: > > > Dear all, > > I have a quite big matrix which I would like to > threshold. > > If the value is below threshold the cell should be > zero > > and > > if the value is over threshold the cell should be one > > M2 <- M > M2[M < thresh] <- 0 > M2[M >= thresh] <- 1 > > or perhaps simply: > > M2 <- as.numeric( M[] < thresh ) > > > > One really simple way to do that is two have a nested > loop and check cell by cell. > > > > The problem is that this seems to be really time > consuming and ineficient. > > > > What do you suggest me to try out? > > -- > David Winsemius, MD > West Hartford, CT > > ______________________________________________ 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.
