[R] How to define a variable in a function that another function uses without using global variables

[R. Michael Weylandt]

Consider this example:

power <- function(n){
    function(x) x^n
} # Note that this function returns a function!

cube <- power(3)

cube(2) # gives 8

That make sense?

Michael

On Wed, Jan 18, 2012 at 1:30 PM, statguy <martinju at mail.com> wrote:
> I would like to know if it is possible to make a function that defines a
> variable in another function without setting that variable globally?
>
> I would i.e. be able to define a variables value inside a function ("one
> level above) which another function makes use of, without setting this
> variable globally.
>
> I have provided this very simple illustrating example.
>
> test1=function(x)
>        {
>        x+y
>        }
> test2=function(y1)
>        {
>        y=y1
>        test1(2,y1)
>        }
>
> Running the second function results in an error:
>> test2(1)
> Error in test1(2) : object 'y' not found
>
> I see 2 possible solutions to this, but neither of them is preferred in my
> more complex situation:
>
> 1. Setting y<<-y_1 globally in test2-function
> 2. making test1 a function of both x and y.
>
> Is there any other way to do this except from the 2 above? I hope someone
> can help me with this.
>
> --
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>
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