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ecd (version 0.6.4)

ecld.gamma: Incomplete gamma function and asymptotic expansion

Description

ecld.gamma is the wrapper for incomplete gamma function $\Gamma(s,x)$. It is mainly to wrap around pgamma. And ecld.gamma_hgeo is the asymptotic expansion of $\Gamma(s,x)$ using hypergeometric series, $e^{-x} x^{s-1} {}_2 F_0 (1,1-s;;-1/x)$. It is mainly used in for star OGF $L^{*}(k;\lambda)$. ecld.gamma_2F0 is simply ${}_2 F_0 (1,1-s;;-1/x)$, which is used in the star OGF expansion.

Usage

ecld.gamma(s, x = 0)
ecld.gamma_hgeo(s, x, order)
ecld.gamma_2F0(s, x, order)

Arguments

s
numeric
x
numeric
order
numeric, the order of the power series

Value

numeric