[R] integrate a fuction

[David Winsemius]

On Mar 4, 2011, at 6:01 PM, santiagorf wrote:

> I'm having a function of the form
>
> 1> f<-function(x){
> 1+
> 1+    return(x^p)
> 1+
> 1+ }
>
> ,and I would like to integrate it with respect to x, where p should  
> be any
> constant.
>
> One way would be to set a value for p globally and then call integrate
> function:
> p=2
> integrate(f, lower = -1, upper = 1)
>
> However, I would like to use 'integrate' inside a function, so I   
> could call
> it passing p as a parameter. I tried something like this:
>
> 1> p=1
> 1> integral<-function(p){
> 1+    integrate(f, lower = -1, upper = 1)
> 1+
> 1+ }
> 1>
> 1> integral(2)
> 0 with absolute error < 1.1e-14
>
> ,but it doesn't work as the integral of f is evaluated with p=1 (the  
> value
> of the global variable p) and not with the value of p=2 when the  
> function
> integral is called.

Functions carry with them environments in whaich they are defined.

>
> Does anyone knows how can I solve this problem?


Build `f` to have two parameters.

-- 
David

> Thanks in advance
> santiagorf
>
>
>
> --
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>
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David Winsemius, MD
Heritage Laboratories
West Hartford, CT