I have quite a complicated problem that's hard to describe. Suppose I have a dataframe d. I want to access the vector d$var, where var is one of the variables in d. Just take for granted that there's a good reason I want to do this as follows.
var<-"DeOxyA" xx<-paste("d$",var, sep="") mean(xx) [1] NA Warning message: In mean.default(xx) : argument is not numeric or logical: returning NA > mean(d$DeOxyA) [1] 21.98904 How can I convert xx so I can do mean(xx), for example? Currently xx is a character, not a variable. as.numeric doesn't do it. I want R to see mean(DeOxyA), not mean("DeOxyA") I'm stumped. Thanks very much for any help. Bill ______________________________________________ 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.