/// <summary>
/// Samples Beta distributed random variables by sampling two Gamma variables and normalizing.
/// </summary>
/// <param name="rnd">The random number generator to use.</param>
/// <param name="a">The A shape parameter.</param>
/// <param name="b">The B shape parameter.</param>
/// <returns>a random number from the Beta distribution.</returns>
internal static double SampleBeta(Random rnd, double a, double b)
{
var x = Gamma.SampleGamma(rnd, a, 1.0);
var y = Gamma.SampleGamma(rnd, b, 1.0);
return(x / (x + y));
}
