Message-ID: <mn.3a807d833043a6af.83239@exitcheck.net>
Date: 2008-03-07T18:40:42Z
From: Max
Subject: Numerical Integration in 1D
Dear UseRs,
I'm curious about the derivative of n!.
We know that Gamma(n+1)=n! So when on takes the derivative of
Gamma(n+1) we get Int(ln(x)*exp(-x)*x^n,x=0..Inf).
I've tried code like
> integrand<-function(x) {log(x)*exp(x)*x^n}
> integrate(integrand,lower=0,upper=Inf)
It seems that R doesn't like to integrate for any n, and I was
wondering if anyone knew a way around this?
-Max