[R] evaluation question

[Uwe Ligges]

On 22.11.2011 19:23, Erin Hodgess wrote:
> Dear R People:
>
> Hope you're having a nice day.
>
> Here is a character vector:
>
>> yz
> [1] "pexp(3.2,rate=1)"
>> str(yz)
>   chr "pexp(3.2,rate=1)"
>>
> And I would like to evaluate that vector.
>
> I tried:
>> eval(as.expression(yz))
> [1] "pexp(3.2,rate=1)"
>>
>
> But that doesn't work.
>
> Any suggestions would be most welcome.  I have a feeling that it's
> quite simple and that I'm having a forest vs. trees issue.


Erin,

you need to parse() the text before eval()uating it. In most cases, the 
original problem is why you got the text and not already something that 
is a language object.

Best,
Uwe


>
> Thanks,
> Erin
>
>