public double GetCdf(double x)
{
return(GammaHelper.RegularizedGammaP(R * 0.5, x * 0.5));
}
public double GetInvCdf(double p)
{
return(2 * GammaHelper.InverseRegularizedGammaP(R * 0.5, p));
}
public double GetPdf(double x)
{
return(Math.Pow(x, (R * 0.5) - 1d) * Math.Exp(-x * 0.5)
/ (GammaHelper.Gamma(0.5 * R) * Math.Pow(2, R * 0.5)));
}