\section{Endcap\-Helix\-Fitter Class Reference}
\label{classEndcapHelixFitter}\index{Endcap\-Helix\-Fitter@{Endcap\-Helix\-Fitter}}


A class to make it quick to fit a track or hits and get back the chi2 and Ndf values and also bundle the code used for that, so it doesn't have to be copied all over the places.  




{\ttfamily \#include $<$Endcap\-Helix\-Fitter.\-h$>$}

\subsection*{Public Member Functions}
\begin{DoxyCompactItemize}
\item 
{\bfseries Endcap\-Helix\-Fitter} (Track $\ast$track)  throw ( Endcap\-Helix\-Fitter\-Exception )\label{classEndcapHelixFitter_a7318652472ca069308ffcebaa9babb37}

\item 
{\bfseries Endcap\-Helix\-Fitter} (std\-::vector$<$ Tracker\-Hit $\ast$ $>$ tracker\-Hits)  throw ( Endcap\-Helix\-Fitter\-Exception )\label{classEndcapHelixFitter_ae81575e7121295b6043089fc44c3c92a}

\item 
double {\bfseries get\-Chi2} ()\label{classEndcapHelixFitter_ae22ccda3a35213d2eac54694f6f3b317}

\item 
int {\bfseries get\-Ndf} ()\label{classEndcapHelixFitter_adc51058522a16cc08174d051ef610b43}

\item 
float {\bfseries get\-Omega} ()\label{classEndcapHelixFitter_a5e175959d7cb683e11cf22981dfbc4c2}

\item 
float {\bfseries get\-Tan\-Lambda} ()\label{classEndcapHelixFitter_a0cd3b67b535b1ba86fabf69a7dc1e365}

\item 
float {\bfseries get\-Phi0} ()\label{classEndcapHelixFitter_a0dc55a9b4819394762e20d0f65f967c7}

\item 
float {\bfseries get\-D0} ()\label{classEndcapHelixFitter_a8da631adcfaf9c48042cc7f0366adef1}

\item 
float {\bfseries get\-Z0} ()\label{classEndcapHelixFitter_abe94c640690dd3a73c1aba7a614ac8f4}

\end{DoxyCompactItemize}


\subsection{Detailed Description}
A class to make it quick to fit a track or hits and get back the chi2 and Ndf values and also bundle the code used for that, so it doesn't have to be copied all over the places. 

Uses a helix fit from the Marlin\-Trk class Helix\-Fit.\-cc It is named V\-X\-D\-Helix\-Fitter, because it makes some assumptions about the hits, that come from them being on the V\-X\-D. Specifically the errors passed to the helix fit are calculated on the assumption, that du and dv are errors in the xy plane. If this class is intended to be used for hits on different detectors, a careful redesign is necessary! 

The documentation for this class was generated from the following files\-:\begin{DoxyCompactItemize}
\item 
Endcap\-Helix\-Fitter.\-h\item 
Endcap\-Helix\-Fitter.\-cc\end{DoxyCompactItemize}
