Digamma function, the derivative of lgamma. Equivalent to R's digamma(). Takes a single number.
lgamma
digamma()
Argument.
psi(x) (NaN at zero and the negative integers).
NaN
digamma(1); // -0.5772156649015329 (minus Euler's constant) Copy
digamma(1); // -0.5772156649015329 (minus Euler's constant)
Digamma function, the derivative of
lgamma. Equivalent to R'sdigamma(). Takes a single number.