on 09/16/2008 09:20 AM [EMAIL PROTECTED] wrote: >>> Does anyone know an easy way to convert all the zero values in a >> imported csv table into NA's >> >> Depends on the data structure you gave your imported table. In a >> single numeric vector (named, say, vec), the syntax is >> >> is.na(vec[vec==0]) <- TRUE > > That throws errors for me. An alternative is > vec[vec==0] <- NA > > This also works for data frames, e.g. > df <- data.frame(a=c(1,2,3,0,3,4,0,5,2), b=c(1,0,0,1,1,0,1,1,0)) > df[df==0] <- NA >
The correct syntax using is.na() would be: > df a b 1 1 1 2 2 0 3 3 0 4 0 1 5 3 1 6 4 0 7 0 1 8 5 1 9 2 0 is.na(df) <- df == 0 > df a b 1 1 1 2 2 NA 3 3 NA 4 NA 1 5 3 1 6 4 NA 7 NA 1 8 5 1 9 2 NA Review ?is.na for correct use. HTH, Marc Schwartz ______________________________________________ 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.
