On Mon, Feb 15, 2010 at 11:24 AM, David Winsemius <dwinsem...@comcast.net> wrote: > > On Feb 15, 2010, at 11:01 AM, hadley wickham wrote: > >>> I, personally, utilize the ifelse(test,statement,statement) function when >>> possible over the methodology outlined. >> >> if + else and ifelse perform quite different tasks, and in general can >> not (and should not) be exchanged. In particular, note that for >> ifelse, "the class attribute of the result is taken from ‘test’ and >> may be inappropriate for the values selected from ‘yes’ and 'no’". > > I have always been puzzled by that bit of advice/knowledge on the help page. > "test" will of necessity be of class "logical", and yet I regularly succeed > in producing numeric and character vectors with ifelse. In fact ifelse would > be rather limited in utility if it only returned logical vectors. >
I think it had intended to refer to oldClass rather than class. > oldClass(TRUE) NULL > oldClass(ifelse(TRUE, 1, 2)) NULL ______________________________________________ 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.
