as.numeric with tclvalue redux

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?

thanks,
Erin

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?

  

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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