On Wednesday 09 July 2008, Ben Bolker wrote: > ACroske <Audy3272 <at> yahoo.com> writes: > > I have a large matrix full of probabilities; I would like to convert each > > probability to a 1 or a 0 using rbinom. > > How can I do this on the entire matrix? The matrix was converted from a > > raster ArcMap dataset, so the matrix is essentially a map. Because of > > this, I have no column headings. > > Thanks! > > How about > > matrix(rbinom(length(m),prob=m,size=1),nrow=nrow(m)) > > or (perhaps marginally more efficiently?) > > y <- (runif(m)<m) > storage.mode(y) <- "double" > > Ben Bolker >
Wait a second. Are you trying to convert each probability into the most likely '1' or '0' through rounding? The code example above will give you a different answer every time you run it. Is that what you are looking for? Just curious, Dylan -- Dylan Beaudette Soil Resource Laboratory http://casoilresource.lawr.ucdavis.edu/ University of California at Davis 530.754.7341 ______________________________________________ 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.
