Re: [Audacity-nyquist] Pascal's triangle done

[Roger D. <rb...@cs...>]

paul beach wrote:
> Xlisp has a function and, also a  graph for Binomial Distribution. Since
> the graph is not symetrical; I assume, a continuous formula is being
> used, or Sterling estimate. 
>   
Are you refering to the probability distribution? Here's the code from 
lib/distributions.lsp:

(defun bernoulli-dist (px1 &optional (x1 1) (x2 0))
  (let ((u (rrandom)))
    (if (< u px1) x1 x2)))

(defun binomial-dist (n p)
  (let ((suc 0))
    (dotimes (count n suc)
      (setf suc (+ suc (bernoulli-dist p))))))

-Roger
> Since 70! = 70x69x68... is about 100 digits, you can see that using the
> binomial coeffiecient might be rather awkward. 
>
> The binomial distribution should be discreet integers. This could be
> implemented, "honestly" with the use of Pascal's triangle, which Edgar
> has posted.
>
> http://mathworld.wolfram.com/BinomialDistribution.html
>