Function trv::maths::eval_lanczos_approx_series#
Defined in File maths.cpp
Function Documentation#
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std::complex<double> trv::maths::eval_lanczos_approx_series(std::complex<double> z)#
Evaluate the Lanczos approximation series \( A_g(z) \) for the gamma function.
The series approximate the gamma function by
\[ \Gamma(z + 1) = \sqrt{2\pi} (z + g + 1/2)^{z + 1/2} \mathrm{e}^{- z - g - 1/2} A_g(z) \]where \( g \) is the Lanczos constant.- Parameters
z – Complex argument.
- Returns
Value of \( A_g(z) \).