Thanks for the answers. They were very helpful. I did it like below. data$z <- ifelse(data$x == "A" & data$y == "A", "NA", "B").
That is enough for today. I guess I learned a enough today. Thanks to everbody who tried to help. -- View this message in context: http://r.789695.n4.nabble.com/if-else-statements-in-data-frame-tp3454646p3454710.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.
