In This Package:

LineTraj.cpp

Go to the documentation of this file.

// $Id: LineTraj.cpp,v 1.14 2007/10/16 11:50:59 wouter Exp $
// Include files

// local
#include "Kernel/LineTraj.h"
#include "GaudiKernel/SystemOfUnits.h"
using namespace LHCb;
using namespace ROOT::Math;

std::auto_ptr<Trajectory> LineTraj::clone() const
{
  return std::auto_ptr<Trajectory>(new LineTraj(*this));
}


LineTraj::LineTraj( const Point& begPoint,
                    const Point& endPoint )
  : Trajectory(-(XYZVector(endPoint-begPoint)).r()/2.,(XYZVector(endPoint-begPoint)).r()/2.),
    m_dir(endPoint-begPoint),
    m_pos(begPoint+0.5*m_dir)
{
  m_dir = m_dir.Unit();
};

Trajectory::Point LineTraj::position( double arclength ) const
{
  return m_pos + arclength * m_dir;
};

Trajectory::Vector LineTraj::direction( double /* arclength*/ ) const
{
  return m_dir;
};

Trajectory::Vector LineTraj::curvature( double /* arclength */ ) const 
{
  return Vector(0,0,0);
};

void LineTraj::expansion( double arclength,
                          Point& p,
                          Vector& dp,
                          Vector& ddp ) const
{
  ddp = Vector(0,0,0);
  dp  = m_dir;
  p   = m_pos + arclength * m_dir;
};

double LineTraj::muEstimate( const Point& point ) const
{
  return m_dir.Dot(point-m_pos);
};

// 1st order approx OK everywhere
double LineTraj::distTo1stError( double , double , int ) const 
{
  return 10*Gaudi::Units::km;
};

// 2nd order approx OK everywhere
double LineTraj::distTo2ndError( double , double , int ) const
{
  return 10*Gaudi::Units::km;
};

---