\hypertarget{namespacevertex__lcfi_1_1util}{\subsection{vertex\-\_\-lcfi\-:\-:util Namespace Reference}
\label{namespacevertex__lcfi_1_1util}\index{vertex\-\_\-lcfi\-::util@{vertex\-\_\-lcfi\-::util}}
}


Utility classes for the vertex package.  


\subsubsection*{Classes}
\begin{DoxyCompactItemize}
\item 
class \hyperlink{classvertex__lcfi_1_1util_1_1HelixRep}{Helix\-Rep}
\begin{DoxyCompactList}\small\item\em Multi-\/\-Perpose 3 Vector. \end{DoxyCompactList}\item 
class \hyperlink{classvertex__lcfi_1_1util_1_1Vector3}{Vector3}
\begin{DoxyCompactList}\small\item\em Multi-\/\-Perpose 3 Vector. \end{DoxyCompactList}\end{DoxyCompactItemize}
\subsubsection*{Enumerations}
\begin{DoxyCompactItemize}
\item 
enum \hyperlink{namespacevertex__lcfi_1_1util_ae6c57de90ec755851eeecba3d0088cc6}{Projection} 
\begin{DoxyCompactList}\small\item\em Projection Type. \end{DoxyCompactList}\end{DoxyCompactItemize}
\subsubsection*{Functions}
\begin{DoxyCompactItemize}
\item 
\hypertarget{namespacevertex__lcfi_1_1util_a593e12f889f4668bebe750b6e0040780}{double \hyperlink{namespacevertex__lcfi_1_1util_a593e12f889f4668bebe750b6e0040780}{gam\-Ser} (double a, double x)}\label{namespacevertex__lcfi_1_1util_a593e12f889f4668bebe750b6e0040780}

\begin{DoxyCompactList}\small\item\em Incomplete gamma function P(a,x) via its series representation. \end{DoxyCompactList}\item 
\hypertarget{namespacevertex__lcfi_1_1util_a93596fb5e9bd40f632b14f5eeea6242e}{double \hyperlink{namespacevertex__lcfi_1_1util_a93596fb5e9bd40f632b14f5eeea6242e}{gam\-Cf} (double a, double x)}\label{namespacevertex__lcfi_1_1util_a93596fb5e9bd40f632b14f5eeea6242e}

\begin{DoxyCompactList}\small\item\em Computation of the incomplete gamma function P(a,x) via its continued fraction representation. \end{DoxyCompactList}\item 
\hypertarget{namespacevertex__lcfi_1_1util_a1f5c24955c13540c1689691be795a0a8}{double \hyperlink{namespacevertex__lcfi_1_1util_a1f5c24955c13540c1689691be795a0a8}{gamma} (double a, double x)}\label{namespacevertex__lcfi_1_1util_a1f5c24955c13540c1689691be795a0a8}

\begin{DoxyCompactList}\small\item\em Computation of the upper incomplete gamma function P(a,x) \end{DoxyCompactList}\item 
double \hyperlink{namespacevertex__lcfi_1_1util_aed71d6be58fc344e163ccecc192f81c5}{ln\-Gamma} (double z)
\begin{DoxyCompactList}\small\item\em Computation of ln\mbox{[}gamma(z)\mbox{]} for all z$>$0. \end{DoxyCompactList}\item 
\hypertarget{namespacevertex__lcfi_1_1util_a39066d5c9723ede74496da9b425497ad}{double \hyperlink{namespacevertex__lcfi_1_1util_a39066d5c9723ede74496da9b425497ad}{prob} (double Chi\-Squared, double Degrees\-Of\-Freedom)}\label{namespacevertex__lcfi_1_1util_a39066d5c9723ede74496da9b425497ad}

\begin{DoxyCompactList}\small\item\em Calculate probability from Chi Squared and Degrees of freedom. \end{DoxyCompactList}\end{DoxyCompactItemize}


\subsubsection{Detailed Description}
Utility classes for the vertex package. 

\subsubsection{Function Documentation}
\hypertarget{namespacevertex__lcfi_1_1util_aed71d6be58fc344e163ccecc192f81c5}{\index{vertex\-\_\-lcfi\-::util@{vertex\-\_\-lcfi\-::util}!ln\-Gamma@{ln\-Gamma}}
\index{ln\-Gamma@{ln\-Gamma}!vertex_lcfi::util@{vertex\-\_\-lcfi\-::util}}
\paragraph[{ln\-Gamma}]{\setlength{\rightskip}{0pt plus 5cm}double vertex\-\_\-lcfi\-::util\-::ln\-Gamma (
\begin{DoxyParamCaption}
\item[{double}]{z}
\end{DoxyParamCaption}
)}}\label{namespacevertex__lcfi_1_1util_aed71d6be58fc344e163ccecc192f81c5}


Computation of ln\mbox{[}gamma(z)\mbox{]} for all z$>$0. 

The algorithm is based on the article by C.\-Lanczos \mbox{[}1\mbox{]} as denoted in Numerical Recipes 2nd ed. on p. 207 (W.\-H.\-Press et al.). \mbox{[}1\mbox{]} C.\-Lanczos, S\-I\-A\-M Journal of Numerical Analysis B1 (1964), 86. The accuracy of the result is better than 2e-\/10. 