betaLn function

double betaLn (double z, double w)

Computes the logarithm of the Euler Beta function.

Implementation

double betaLn(double z, double w) {
  if (z <= 0.0) {
    throw ArgumentError.value(z, 'z', messages.argumentPositive);
  }

  if (w <= 0.0) {
    throw ArgumentError.value(w, 'w', messages.argumentPositive);
  }

  return gammaLn(z) + gammaLn(w) - gammaLn(z + w);
}