PBETA

pbeta

The beta distribution function

         F = pbeta(x,a,b)
	Input	x	matrix (elements between 0 and 1)
		a,b	positive reals, parameters of the beta distribution
		(x,a,b  can be scalar or matrix with common size)

	Output	F	for each element of x, F=Prob(X<x) where X is a random 
			variable with beta density :
			x--> x.^(a-1) .* (1-x).^(b-1) ./ beta(a,b)1_{0<x<1}