Hi see ?is.na
x <-sample(c(1:3, NA), 20, replace=T) x [1] 2 NA 2 3 3 3 3 2 3 NA 3 2 1 2 NA 3 3 3 2 2 y<-rnorm(20) y[is.na(x)] [1] 0.1600417 1.3264063 -0.6175832 Regards Petr > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-bounces@r- > project.org] On Behalf Of ramoss > Sent: Friday, November 30, 2012 4:27 PM > To: r-help@r-project.org > Subject: [R] subset data frame by variable with missing value > > Hello, > > I have a variable in a data frame that contains NA values. I just want > to subset so that I get the obs where that variable is missing. > In SAS I would do: > > data missing; > set test; > if myvalue=' '; > run; > > How can I perform this simple task in R? > > Thanks in advance for your help. > > > > -- > View this message in context: http://r.789695.n4.nabble.com/subset- > data-frame-by-variable-with-missing-value-tp4651439.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > 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.