lgamma_stirling()

template<typename T >

return_type_t< T > stan::math::lgamma_stirling ( const T  x )

inline

Return the Stirling approximation to the lgamma function.

\[ \mbox{lgamma_stirling}(x) = \frac{1}{2} \log(2\pi) + (x-\frac{1}{2})*\log(x) - x \]

Template Parameters

T	type of value

Parameters

x

value

Returns

Stirling's approximation to lgamma(x).

Definition at line 26 of file lgamma_stirling.hpp.