Gammainc


Name:
Gammainc - incomplete gamma function
Synopsis:
x a Gammainc -> result  

Examples:
2.2 1.5 Gammainc -> 0.778615  

Description:
Computes the incomplete Gamma function  
int(t^(a-1)*exp(-t), t=0..x) / Gamma(a)

Parameters: x (double): upper limit of integration
a (double): order of Gamma function

Remarks:
This is the incomplete Gamma function P(a,x) defined as no. 6.5.1  
in Abramowitz&Stegun. Requires the GSL.

References:
http://sources.redhat.com/gsl/ref 
Author:
H E Plesser  

FirstVersion:
2001-07-26  

Source:
/home/graber/work-nest/nest-git/nest-simulator/sli/specialfunctionsmodule.h