[R] Problem with scoping a variable value

[Tolga Uzuner]

You are a star... that was it. Many thanks,
Tolga

-----Original Message-----
From: Gabor Grothendieck [mailto:ggrothendieck at gmail.com] 
Sent: 16 February 2006 20:24
To: Tolga Uzuner
Cc: r-help at stat.math.ethz.ch
Subject: Re: [R] Problem with scoping a variable value

Without a reproducible example one can only guess but
perhaps the problem is not show but that you have a variable
F.  Try writing out F as FALSE.


On 2/16/06, Tolga Uzuner <tolga at coubros.com> wrote:
> Hi there,
>
> I have a function which has a variable called show as an input:
>
> richardson.grad <- function(func, x, d=0.01, eps=1e-4, r=6, show=F){
> # do some things
>   if(show) {
>
>        cat("\n","first order approximations", "\n")
>        print(a.mtr, 12)
>
>
>    }
> #do more things and return
> }
>
> The show variable is being used as a flag to show intermediate results.
>
> Interestingly enough, I have downloaded a package recently which defines
> the show variable as a function:
>
>  > show
> standardGeneric for "show" defined from package "methods"
>
> function (object)
> standardGeneric("show")
> <environment: 01676F7C>
> Methods may be defined for arguments: object
>
>  >
>
> Now, all of a sudden, the function I had defined earlier is scoping up
> to this new value, and is thus not working:
>
>  > richardson.grad(function(x) x^2,2)
> Error in if (show) { : argument is not interpretable as logical
>  >
>
> I could always redefine show in richardson.grad to be something else but
> something seems wrong: why is richardson.grad not looking up show's
> value in the  function ? How would I fix this ?
>
> Thanks in advance,
> Tolga
>
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide!
http://www.R-project.org/posting-guide.html
>