R-alpha: two-sided to one-sided formula

Douglas Bates bates@stat.wisc.edu
02 Dec 1997 12:34:49 -0600


Peter Dalgaard BSA <p.dalgaard@biostat.ku.dk> writes:

> Douglas Bates <bates@stat.wisc.edu> writes:
> 
> > In general it would not be a good idea to propagate the formula class
> > to subsets but it does make sense in this case.  We can get around it
> > by replacing ttt[-2] by do.call("~", ttt[-(1:2)]) I suppose.  Any
> > opinions on whether ttt[-2] should still be a formula?
> 
> Hum. tt[-i] is a well-defined formula iff (i != 1). Somehow, I dislike
> the idea of properties depending on the value of a parameter, so I'm
> inclined to say no. BTW,
> 
> eval(as.call(ttt[-2]))
> 
> also works.

I agree with Peter.  We will change our code.
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !)  To: r-devel-request@stat.math.ethz.ch
_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._