Message-ID: <47E7EF55.8030608@biostat.ku.dk>
Date: 2008-03-24T18:13:41Z
From: Peter Dalgaard
Subject: as.numeric with tclvalue redux
In-Reply-To: <7acc7a990803241039h1f11c323id1d069a1309d8913@mail.gmail.com>
Erin Hodgess wrote:
> Hi again R People:
>
> This works fine:
>
>> library(tcltk)
>> a <- tclVar("4.5")
>> as.numeric(tclvalue(a))
>>
> [1] 4.5
>
>> #But if you have:
>> b <- tclVar("pi")
>> as.numeric(tclvalue(b))
>>
> [1] NA
> Warning message:
> NAs introduced by coercion
>
>
> Is anyone aware of a way around this, please?
>
>
Brian already told you: Parse and eval.
> eval(parse(text=as.character(tclvalue(tclVar("pi")))))
[1] 3.141593
(Beware: Depending on the environment in which you eval(), strange
things can happen if you use the name of an internal variable in your
function)
What happened with the Inf issue? I can't reproduce that:
> as.numeric(as.tclObj("Inf"))
[1] Inf
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