Hi,

I need some help getting the hypergeom distr. I've started with this code, but it doesn't seem work:

```
def logchoose(n, k):
lgn = special.gammaln(n+1)
lgk = special.gammaln(k+1)
lgnk = special.gammaln(n-k+1)
return lgn - (lgnk + lgk)
def hypgeo(x, r, b, n):
return exp(logchoose(r, x) + logchoose(b, n-x) - logchoose(r+b, n))
b = 2450
r = 346
N = r + b
n = 5000
x = 1000
p = hypgeo(x,r,b,n)
print p
```