On Fri, 2009-06-12 at 09:55 +0100, Christine Griffiths wrote: > Hello > > I have a dataset in which I would like to replace 0s with NAs. There is a > lot of information on how to replace NAs with 0, but I have struggled to > find anything with regards to doing the reverse. Any recommendations would > be great.
Here is one way: ## some dummy data set.seed(123) dat <- matrix(rnorm(100), ncol = 10) ## add some 0's dat[sample(100, 20)] <- 0 ## convert to df dat <- data.frame(dat) dat ## now replace 0 with NA ## replacement function foo <- function(x) { x[x == 0] <- NA x } ## lapply it, and force back to df dat2 <- data.frame(lapply(dat, foo)) dat2 HTH G > > Cheers > Christine > > ______________________________________________ > 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. -- %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% Dr. Gavin Simpson [t] +44 (0)20 7679 0522 ECRC, UCL Geography, [f] +44 (0)20 7679 0565 Pearson Building, [e] gavin.simpsonATNOSPAMucl.ac.uk Gower Street, London [w] http://www.ucl.ac.uk/~ucfagls/ UK. WC1E 6BT. [w] http://www.freshwaters.org.uk %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% ______________________________________________ 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.