pub fn ln_beta(a: f64, b: f64) -> f64
Computes the natural logarithm of the beta function where a is the first beta parameter and b is the second beta parameter and a > 0, b > 0.
a
b
a > 0
b > 0
if a <= 0.0 or b <= 0.0
a <= 0.0
b <= 0.0