CDCTrajectorySZ Class Reference

Linear trajectory in sz space. More...

#include <CDCTrajectorySZ.h>

Collaboration diagram for CDCTrajectorySZ:

Public Member Functions
	CDCTrajectorySZ ()
	Default constructor for ROOT compatibility.
	CDCTrajectorySZ (const UncertainSZLine &szLine)
	Constructs the trajectory from the given two dimensional sz line.
	CDCTrajectorySZ (const double tanLambda, const double z0)
	Constructs the trajectory with the given slope and start z.
double	mapSToZ (const double s=0) const
	Translates the travel distance to the z coordinate.
double	mapPtToPz (const double pt) const
	Translates the absolute value of the transvers momentum to the momentum in z direction. More...
double	getZDist (const double s, const double z) const
	Calculates the distance along between the given point an the sz trajectory.
double	getSZDist (const double s, const double z) const
	Gets the signed distance of the sz point to the line in the sz plane This gives the signed distance of a given point in the sy plane Errors in s and z are equaly weighted in this distance ( which might be an incorrect choice to fit to ). More...
void	passiveMoveS (const double deltaS)
	Passively Shift the s coordinate by the amount given. More...
bool	isFitted () const
	Indicates if the line has been fitted.
void	clear ()
	Clears all information from this trajectory line.
double	getTanLambda () const
	Getter for the slope over the travel distance coordinate.
double	getZ0 () const
	Getter for the z coordinate at zero travel distance.
double	getPValue () const
	Getter for p-value.
double	getChi2 () const
	Getter for the chi square value of the line fit.
void	setChi2 (const double chi2)
	Setter for the chi square value of the line fit.
size_t	getNDF () const
	Getter for the number of degrees of freedom of the line fit.
void	setNDF (std::size_t ndf)
	Setter for the number of degrees of freedom of the line fit.
const UncertainSZLine &	getSZLine () const
	Getter for the line in sz space.
void	setSZLine (const UncertainSZLine &szLine)
	Setter for the line in sz space.

Static Public Member Functions
static SZCovariance	getBasicSZCovariance ()
	Getter for a default assumption about the parameter covariances.
static CDCTrajectorySZ	basicAssumption ()
	Constucts a basic assumption, what the z0 start position and the sz slope are, including some broad values for the covariance matrix.

Private Attributes
UncertainSZLine	m_szLine
	Memory for the line representation.

Detailed Description

Linear trajectory in sz space.

Particle trajectories have a linear dependence between the travel distance s and
the z coordinate as the magnetic fields along z does not disturb the free z movement.
This class presents this trajectory projection by a line representation in sz space. The s coordinate is interpreted as the transvers travel distance, hence
the part of the travel distance see in the xy projection.

Definition at line 31 of file CDCTrajectorySZ.h.

Member Function Documentation

getSZDist()

double getSZDist ( const double  s, const double  z  ) const

inline

Gets the signed distance of the sz point to the line in the sz plane This gives the signed distance of a given point in the sy plane
Errors in s and z are equaly weighted in this distance
( which might be an incorrect choice to fit to ).

The plus sign mean the point is below the line. For minus it is above. The later is naturally choosen as the direction of positiv advance is
coaligned with the s axes

Definition at line 80 of file CDCTrajectorySZ.h.

      { return getSZLine()->distance(Vector2D(s, z)) ; }

mapPtToPz()

double mapPtToPz ( const double  pt ) const

inline

Translates the absolute value of the transvers momentum to the momentum in z direction.

Scales the absolute value of the transvers momentum to the z component of the momentum vector. The z component comes with the correct sign as reflected by increasing or decreasing z component. Note : This assumes s to be the transvers travel distance.

Definition at line 64 of file CDCTrajectorySZ.h.

passiveMoveS()

void passiveMoveS ( const double  deltaS )

inline

Passively Shift the s coordinate by the amount given.

Adjust all transvers travel distance measurements by deltaS.
The old values of s before the shift corresponds the new scale
like old_s - deltaS = new_s. This corresponds to an passive transformation
of s by deltaS. This can be used in conjunction with the return value of
CDCTrajectory2D::setStartPos2D() in order to move the transvers travel distance
by the same amount in both trajectories.

Definition at line 92 of file CDCTrajectorySZ.h.

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

• tracking/trackFindingCDC/eventdata/trajectories/include/CDCTrajectorySZ.h
• tracking/trackFindingCDC/eventdata/trajectories/src/CDCTrajectorySZ.cc