Easy using rowSums : > x <- data.frame(X1=c(0,0,1),X2=c(1,1,1),X3=c(0,1,0))
> x$Nulls <- rowSums(x==0) > x X1 X2 X3 Nulls 1 0 1 0 2 2 0 1 1 1 3 1 1 0 1 Cheers On Tue, Mar 30, 2010 at 6:31 PM, Thomas Jensen < thomas.jen...@eup.gess.ethz.ch> wrote: > Dear R-list, > > Sorry for spamming the list lately, I am just learning the more advanced > aspects of R! > > I have some data that looks like this: > > Out Country1 Country 2 Country 3 ... CountryN > 1 1 1 1 1 > 0 1 1 0 1 > 1 1 0 1 0 > > I want to create a new variable that counts the number of zeros in every > row whenever Out is equal to 1, and else it is a zero, so it would look > like this: > > new_var > 0 > 0 > 2 > > I have tried the following: > > for (i in length(Out)){ > if (Out == 1) {new_var <- sum(dat[i,] != 1)} > else {new_var <- 0} > } > > but this gives me an error message. > > Best, Thomas > > ______________________________________________ > 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. > -- Joris Meys Statistical Consultant Ghent University Faculty of Bioscience Engineering Department of Applied mathematics, biometrics and process control Coupure Links 653 B-9000 Gent tel : +32 9 264 59 87 joris.m...@ugent.be ------------------------------- Disclaimer : http://helpdesk.ugent.be/e-maildisclaimer.php [[alternative HTML version deleted]] ______________________________________________ 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.