[R] formula form of coxph

[Yihui Xie]

> idx = c(1,3,5)
> as.formula(paste("Surv(time, status)~", paste("x", idx, sep = "", collapse = "+")))
Surv(time, status) ~ x1 + x3 + x5

Regards,
Yihui
--
Yihui Xie <xieyihui at gmail.com>
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On Fri, Oct 3, 2008 at 1:32 PM, Xing Yuan <joe.yuan0309 at gmail.com> wrote:
> Dear R user,
>
> I got a question when using the coxph function. I have 5 covariates x1, x2,
> x3, x4, x5 and I want to write a function so that when given an indicator,
> e.g., c(1,3,5), I can fit the model as
> model=coxph(Surv(time, status)~x1+x3+x5). Any idea to play around the form
> of formula?
>
> Thank you very much!
>
> Xing Yuan
> University of Pittsburgh
>