MATLAB: Numeircal integral with external function and external parameter

Question

I would like to calculate an integral whereas the integrand is a separate external function. Consider as an example that I have in my main script:

N=5; 
I = integral(fn,0,Inf,'RelTol',1e-8,'AbsTol',1e-13)

Where N is a parameter of the integrand that appears in the separate function named: fn.m that has the following form:

function FUN= fn(x)
	FUN=@(x) (x.^N).*exp(-x).*sin(x)
 end

But when I do this I see the following error:

Undefined function or variable 'N'.

How can I help Matlab take this external parameter into the integrand function?

Answer 1

EDITED

Parameterize function

N = 5; 
F = fn(x,N); % function call
I = integral(F,0,Inf,'RelTol',1e-8,'AbsTol',1e-13) 
function FUN = fn(x,N) % function definition
	FUN = @(x) (x.^N).*exp(-x).*sin(x);
end

Gives:

I =
  -15.0000