x = rbeta(n,a,b) Input n positive integer or a vector [lig,col] of 2 positive integers a,b positive reals Output x n-vector or a n-matrix of random numbers chosen from a beta distribution with parameters a and b (density : x--> x.^(a-1) .* (1-x).^(b-1) ./ beta(a,b)1_{0<x<1}