JBLHelix Class Reference

A helix, parametrized by (kappa, phi0, theta, dca, z0). More...

#include <JBLHelix.h>

List of all members.

Public Member Functions

JBLHelix (double kappa, double phi0, double theta, double dca, double z0)

Constructor from (kappa, phi0, theta, dca, z0).

JBLHelix (double par_[])

Constructor from an array of values.

~JBLHelix ()

Destructor.

double getPar (int i)

Get value of parameter i.

JBLHelix & setPar (int i, double par_)

Set value of parameter i.

int getClosestApproach (const JBLHelix &h1, double &s0, double &s1, double &s02nd, double &s12nd) const

Get arc lengths for point where another helix comes closest.

double getClosestS (const TwoVector &p) const

Return s of point on helix where helix comes closest in (x,y) to given point.

double getClosestS (const ThreeVector &p) const

Return s of point on helix where helix comes closest in (x,y) to given point.

void getTrajectoryPointEx (double s, ThreeVector &p) const

Get point along trajectory into existing 3-vector.

ThreeVector getTrajectoryPoint (double s) const

Get point along trajectory.

double getTrajectoryZ (double s) const

Get z value along trajectory.

void getCenterPointEx (TwoVector &p) const

Get center point of trajectory into existing 2-vector.

TwoVector getCenterPoint () const

Get center point of trajectory.

double getNormalS (double s) const

Get smallest s that corresponds to same (x, y).

Private Types

enum { NPAR = 5 }

Private Attributes

double par [NPAR]

Parameters (kappa, phi0, theta, dca, z0).

Detailed Description

A helix, parametrized by (kappa, phi0, theta, dca, z0).

The main purpose of an JBLHelix is that it can be "intersected" with another JBLHelix object, giving estimates for arc length values s1 and s2 of the two helices where the two helices intersect each other in r/phi and come closest in z

Parameters:

0: kappa (signed)
1: phi0
2: theta
3: dca
4: z0

Definition at line 33 of file JBLHelix.h.

Member Enumeration Documentation

anonymous enum [private]

Enumeration values:

NPAR

Definition at line 102 of file JBLHelix.h.

Constructor & Destructor Documentation

JBLHelix::JBLHelix ( double kappa,

double phi0,

double theta,

double dca,

double z0

)

Constructor from (kappa, phi0, theta, dca, z0).

Parameters:

kappa kappa

phi0 phi0

theta theta

dca dca

z0 z0

Definition at line 16 of file JBLHelix.C.
References setPar().

JBLHelix::JBLHelix ( double par_[] )

Constructor from an array of values.

Parameters:

par_ Parameters (kappa, phi0, theta, dca, z0)

Definition at line 29 of file JBLHelix.C.
References NPAR, and setPar().

JBLHelix::~JBLHelix ( )

Destructor.

Definition at line 33 of file JBLHelix.C.

Member Function Documentation

TwoVector JBLHelix::getCenterPoint ( ) const

Get center point of trajectory.

Definition at line 171 of file JBLHelix.C.
References getCenterPointEx().
Referenced by getClosestApproach().

void JBLHelix::getCenterPointEx ( TwoVector & p ) const

Get center point of trajectory into existing 2-vector.

Definition at line 166 of file JBLHelix.C.
References par, and TwoVector::setValues().
Referenced by getCenterPoint().

int JBLHelix::getClosestApproach ( const JBLHelix & h1,

double & s0,

double & s1,

double & s02nd,

double & s12nd

) const

Get arc lengths for point where another helix comes closest.
This routine intersects the helices in the (x, y) plane, and then returns the arclengths corresponding to the best intersection point, where the helices come closest in z. If the helices don't intersect in (x, y), the point where they come closest in (x,y) is returned.
The return value indicates: 1: circles touch, just one intersection point 2: circles intersect, 2 intersection points 0: circles dont intersect, point is best approximation
Parameters:

h1 The second helix

s0 This helix's arc length of the best point

s1 The 2nd helix's arc length of the best point

s02nd This helix's arc length of the 2nd best point

s12nd The 2nd helix's arc length of the2nd best point

Definition at line 48 of file JBLHelix.C.
References getCenterPoint(), getClosestS(), getNormalS(), getTrajectoryZ(), and par.
Referenced by VertexFitObject::estimatePosition(), and main().

double JBLHelix::getClosestS ( const ThreeVector & p ) const

Return s of point on helix where helix comes closest in (x,y) to given point.

Parameters:

p The point

Definition at line 133 of file JBLHelix.C.
References getClosestS(), ThreeVector::getX(), and ThreeVector::getY().

double JBLHelix::getClosestS ( const TwoVector & p ) const

Return s of point on helix where helix comes closest in (x,y) to given point.

Parameters:

p The point

Definition at line 107 of file JBLHelix.C.
References getNormalS(), TwoVector::getX(), TwoVector::getY(), and par.
Referenced by getClosestApproach(), getClosestS(), and main().

double JBLHelix::getNormalS ( double s ) const

Get smallest s that corresponds to same (x, y).

Definition at line 177 of file JBLHelix.C.
References par.
Referenced by getClosestApproach(), and getClosestS().

double JBLHelix::getPar ( int i )

Get value of parameter i.

Parameters:

i Parameter number i (i=0...4)

Definition at line 37 of file JBLHelix.C.
References NPAR, and par.

ThreeVector JBLHelix::getTrajectoryPoint ( double s ) const

Get point along trajectory.

Definition at line 160 of file JBLHelix.C.
References getTrajectoryPointEx().
Referenced by VertexFitObject::estimatePosition(), and main().

void JBLHelix::getTrajectoryPointEx ( double s,

ThreeVector & p

) const

Get point along trajectory into existing 3-vector.

Definition at line 137 of file JBLHelix.C.
References par, and ThreeVector::setValues().
Referenced by getTrajectoryPoint().

double JBLHelix::getTrajectoryZ ( double s ) const

Get z value along trajectory.

Definition at line 156 of file JBLHelix.C.
References par.
Referenced by getClosestApproach().

JBLHelix & JBLHelix::setPar ( int i,

double par_

)

Set value of parameter i.

Parameters:

i Parameter number i (i=0...4)

par_ New parameter value

Definition at line 42 of file JBLHelix.C.
References NPAR, and par.
Referenced by JBLHelix().

Member Data Documentation

double JBLHelix::par[NPAR] [private]

Parameters (kappa, phi0, theta, dca, z0).

Definition at line 103 of file JBLHelix.h.
Referenced by getCenterPointEx(), getClosestApproach(), getClosestS(), getNormalS(), getPar(), getTrajectoryPointEx(), getTrajectoryZ(), and setPar().

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

Generated on Fri Sep 14 17:38:36 2007 for Kinfit by

1.3.2


Public Member Functions
	JBLHelix (double kappa, double phi0, double theta, double dca, double z0)
	Constructor from (kappa, phi0, theta, dca, z0).
	JBLHelix (double par_[])
	Constructor from an array of values.
	~JBLHelix ()
	Destructor.
double	getPar (int i)
	Get value of parameter i.
JBLHelix &	setPar (int i, double par_)
	Set value of parameter i.
int	getClosestApproach (const JBLHelix &h1, double &s0, double &s1, double &s02nd, double &s12nd) const
	Get arc lengths for point where another helix comes closest.
double	getClosestS (const TwoVector &p) const
	Return s of point on helix where helix comes closest in (x,y) to given point.
double	getClosestS (const ThreeVector &p) const
	Return s of point on helix where helix comes closest in (x,y) to given point.
void	getTrajectoryPointEx (double s, ThreeVector &p) const
	Get point along trajectory into existing 3-vector.
ThreeVector	getTrajectoryPoint (double s) const
	Get point along trajectory.
double	getTrajectoryZ (double s) const
	Get z value along trajectory.
void	getCenterPointEx (TwoVector &p) const
	Get center point of trajectory into existing 2-vector.
TwoVector	getCenterPoint () const
	Get center point of trajectory.
double	getNormalS (double s) const
	Get smallest s that corresponds to same (x, y).
Private Types
enum	{ NPAR = 5 }
Private Attributes
double	par [NPAR]
	Parameters (kappa, phi0, theta, dca, z0).