|MATLAB Function Reference|
Logarithm of beta function
L = betaln(Z,W)
computes the natural logarithm of the beta function
log(beta(Z,W)), for corresponding elements of arrays
W, without computing
beta(Z,W). Since the beta function can range over very large or very small values, its logarithm is sometimes more useful.
W must be real and nonnegative. They must be the same size, or either can be scalar.
-708.8616 is slightly less than
beta(x,x) directly would underflow (or be denormal).