Psi

Psi(*args)

Psi function, alias for digamma function.

\Psi(x) = \frac{1}{\Gamma(x)}\frac{\mathrm{d} \Gamma(x)}{\mathrm{d}x}

with \Gamma the Gamma function.

Parameters:
xfloat \in \Rset^*_+ or complex \in \Cset \setminus \Rset_-
Returns:
resultfloat or complex