trkf::SurfLine Class Reference

#include <SurfLine.h>

Inheritance diagram for trkf::SurfLine:

Public Member Functions
	SurfLine ()
	Default constructor. More...
virtual	~SurfLine ()
	Destructor. More...
double	PointingError (const TrackVector &vec, const TrackError &err) const
	Get pointing error of track. More...
void	getStartingError (TrackError &err) const
	Get starting error matrix for Kalman filter. More...
Public Member Functions inherited from trkf::Surface
	Surface ()
	Default constructor. More...
virtual	~Surface ()
	Destructor. More...
virtual Surface *	clone () const =0
	Clone method. More...
virtual bool	isTrackValid (const TrackVector &vec) const =0
	Surface-specific tests of validity of track parameters. More...
virtual void	toLocal (const double xyz[3], double uvw[3]) const =0
	Transform global to local coordinates. More...
virtual void	toGlobal (const double uvw[3], double xyz[3]) const =0
	Transform local to global coordinates. More...
virtual TrackVector	getDiff (const TrackVector &vec1, const TrackVector &vec2) const
	Calculate difference of two track parameter vectors. More...
virtual void	getPosition (const TrackVector &vec, double xyz[3]) const =0
	Get position of track. More...
virtual TrackDirection	getDirection (const TrackVector &, TrackDirection dir=UNKNOWN) const
	Get direction of track (default UNKNOWN). More...
virtual void	getMomentum (const TrackVector &vec, double mom[3], TrackDirection dir=UNKNOWN) const =0
	Get momentum vector of track. More...
virtual bool	isParallel (const Surface &surf) const =0
	Test whether two surfaces are parallel, within tolerance. More...
virtual double	distanceTo (const Surface &surf) const =0
	Find perpendicular forward distance to a parallel surface. More...
virtual bool	isEqual (const Surface &surf) const =0
	Test two surfaces for equality, within tolerance. More...
virtual std::ostream &	Print (std::ostream &out) const =0
	Printout. More...

Additional Inherited Members
Public Types inherited from trkf::Surface
enum	TrackDirection { FORWARD, BACKWARD, UNKNOWN }
	Track direction enum. More...

Detailed Description

Definition at line 58 of file SurfLine.h.

Constructor & Destructor Documentation

trkf::SurfLine::SurfLine

(

)

Default constructor.

Definition at line 17 of file SurfLine.cxx.

  {}

trkf::SurfLine::~SurfLine ( )

virtual

Destructor.

Definition at line 21 of file SurfLine.cxx.

  {}

Member Function Documentation

void trkf::SurfLine::getStartingError ( TrackError &  err ) const

virtual

Get starting error matrix for Kalman filter.

Get starting error matrix for Kalman filter.

Arguments:

err - Error matrix.

Implements trkf::Surface.

Definition at line 92 of file SurfLine.cxx.

                                                       {
    err.resize(5, false);
    err.clear();
    err(0, 0) = 1000.;
    err(1, 1) = 1000.;
    err(2, 2) = 10.;
    err(3, 3) = 10.;
    err(4, 4) = 10.;
  }

double trkf::SurfLine::PointingError ( const TrackVector &  vec, const TrackError &  err  ) const

virtual

Get pointing error of track.

Get pointing error of track.

Arguments:

vec - Track parameters. err - Track error matrix.

Returns: Pointing error.

This method calculates the track pointing error based on the slope track paramers and errors (parameters 2 and 3).

Implements trkf::Surface.

Definition at line 36 of file SurfLine.cxx.

  {
    // Get slope parameters and error matrix.

    double phi = vec(2);
    double eta = vec(3);
    double epp = err(2, 2);  // sigma^2(phi,phi)
    double ehh = err(3, 3);  // sigma^2(eta,eta)
    double ehp = err(3, 2);  // sigma^2(eta,phi)

    // Calculate error matrix of pointing unit vector in some coordinate system.

    double sh = 1./std::cosh(eta);  // sech(eta)
    double sh2 = sh*sh;
    double sh3 = sh*sh2;
    double sh4 = sh*sh3;

    double th = std::tanh(eta);
    double th2 = th*th;

    double cphi = std::cos(phi);
    double cphi2 = cphi*cphi;

    double sphi = std::sin(phi);
    double sphi2 = sphi*sphi;

    double vxx = sh2*th2*cphi2 * ehh + sh2*sphi2 * epp + 2.*sh2*th*sphi*cphi * ehp;
    double vyy = sh2*th2*sphi2 * ehh + sh2*cphi2 * epp - 2.*sh2*th*sphi*cphi * ehp;
    double vzz = sh4 * epp;

    double vxy = sh2*th2*sphi*cphi * ehh - sh2*sphi*cphi * epp - sh2*th*(cphi2-sphi2) * ehp;
    double vyz = -sh3*th*sphi * ehh + sh3*cphi * ehp;
    double vxz = -sh3*th*cphi * ehh - sh3*sphi * ehp;

    // For debugging.  The determinant of the error matrix should be zero.

    // double det = vxx*vyy*vzz + 2.*vxy*vyz*vxz - vxx*vyz*vyz - vyy*vxz*vxz - vzz*vxy*vxy;

    // Calculate square root of the largest eigenvalue of error matrix.

    double ddd2 = vxx*vxx + vyy*vyy + vzz*vzz
                  - 2.*vxx*vyy - 2.*vxx*vzz - 2.*vyy*vzz
                  + 4.*vxy*vxy + 4.*vyz*vyz + 4.*vxz*vxz;
    double ddd = sqrt(ddd2 > 0. ? ddd2 : 0.);
    double lambda2 = 0.5 * ( vxx + vyy + vzz + ddd);
    double lambda = sqrt(lambda2 > 0. ? lambda2 : 0.);

    return lambda;
  }

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The documentation for this class was generated from the following files:

• lardata/lardata/RecoObjects/SurfLine.h
• lardata/lardata/RecoObjects/SurfLine.cxx