TwoHitVariables Class Reference

Class that allows the calculation of simple variables to check whether a combination of two hits should be used or discarded in tracking. More...

#include <TwoHitVariables.h>

Public Member Functions
	TwoHitVariables (const B2Vector3D &oHit, const B2Vector3D &iHit)
	Constructor.
void	setHits (const B2Vector3D &oHit, const B2Vector3D &iHit)
	Set hits if not given in constructor of if they need to be changed.
double	getCosXY ()
	calculate the cosine of the angle between two vectors in x-y
double	get1DZDistance ()
	get the difference in z between two vectors
double	get1DZDistanceSquared ()
	get the squared difference in z between two vectors
double	get2DXYDistanceSquared ()
	get the squared distance between two vectors in x-y
double	get3DDistanceSquared ()
	get the square of the difference of two vectors
double	getRZSlope ()
	get an estimate for the slope in R-z, similar to theta
double	getDistanceInTimeU (const SpacePoint &outerSpacePoint, const SpacePoint &innerSpacePoint)
	get the time difference of two space points for the u-side measurement
double	getDistanceInTimeV (const SpacePoint &outerSpacePoint, const SpacePoint &innerSpacePoint)
	get the time difference of two space points for the v-side measurement
void	setBFieldZ (const double bfieldZ=1.5)
	Set the B-Field value used for pT calculations.

Private Attributes
double	m_BFieldZ = 1.5
	BField along z to estimate pT.
B2Vector3D	m_oHit
	outermost hit position
B2Vector3D	m_iHit
	innermost hit position

Detailed Description

Class that allows the calculation of simple variables to check whether a combination of two hits should be used or discarded in tracking.

Definition at line 23 of file TwoHitVariables.h.

Constructor & Destructor Documentation

TwoHitVariables()

TwoHitVariables ( const B2Vector3D &  oHit, const B2Vector3D &  iHit  )

inline

Constructor.

Parameters

oHit	B2Vector3D of the outer hit used for calculating the single variables
iHit	B2Vector3D of the inner hit used for calculating the single variables

Definition at line 28 of file TwoHitVariables.h.

                                                                      : m_oHit(oHit), m_iHit(iHit)
      {};

Member Function Documentation

get1DZDistance()

double get1DZDistance ( )

inline

get the difference in z between two vectors

Definition at line 47 of file TwoHitVariables.h.

      {
        return m_oHit.Z() - m_iHit.Z();
      }

get1DZDistanceSquared()

double get1DZDistanceSquared ( )

inline

get the squared difference in z between two vectors

Definition at line 53 of file TwoHitVariables.h.

      {
        return (m_oHit.Z() - m_iHit.Z()) * (m_oHit.Z() - m_iHit.Z());
      }

get2DXYDistanceSquared()

double get2DXYDistanceSquared ( )

inline

get the squared distance between two vectors in x-y

Definition at line 59 of file TwoHitVariables.h.

      {
        return (m_oHit - m_iHit).Perp2();
      }

get3DDistanceSquared()

double get3DDistanceSquared ( )

inline

get the square of the difference of two vectors

Definition at line 65 of file TwoHitVariables.h.

      {
        return (m_oHit - m_iHit).Mag2();
      }

getCosXY()

double getCosXY ( )

inline

calculate the cosine of the angle between two vectors in x-y

Definition at line 41 of file TwoHitVariables.h.

      {
        return (m_oHit.X() * m_iHit.X() + m_oHit.Y() * m_iHit.Y()) / (m_oHit.Perp() * m_iHit.Perp());
      }

getDistanceInTimeU()

double getDistanceInTimeU ( const SpacePoint &  outerSpacePoint, const SpacePoint &  innerSpacePoint  )

inline

get the time difference of two space points for the u-side measurement

Parameters

outerSpacePoint	outer space point used for calculating the time difference in u
innerSpacePoint	inner space point used for calculating the time difference in u

Definition at line 87 of file TwoHitVariables.h.

      {
        return outerSpacePoint.TimeU() - innerSpacePoint.TimeU();
      }

getDistanceInTimeV()

double getDistanceInTimeV ( const SpacePoint &  outerSpacePoint, const SpacePoint &  innerSpacePoint  )

inline

get the time difference of two space points for the v-side measurement

Parameters

outerSpacePoint	outer space point used for calculating the time difference in v
innerSpacePoint	inner space point used for calculating the time difference in v

Definition at line 95 of file TwoHitVariables.h.

      {
        return outerSpacePoint.TimeV() - innerSpacePoint.TimeV();
      }

getRZSlope()

double getRZSlope ( )

inline

get an estimate for the slope in R-z, similar to theta

Definition at line 71 of file TwoHitVariables.h.

      {
        double result = atan(
                          sqrt(std::pow(double(m_oHit.X() - m_iHit.X()), 2)
                               + std::pow(double(m_oHit.Y() - m_iHit.Y()), 2)) /
                          double(m_oHit.Z() - m_iHit.Z()));
        // atan also returns negative angles, so map back to [0,Pi] otherwise one get two peaks at +/-Pi/2 for 90 degree angles
        if (result < 0.0) result += M_PI;
 
        // TODO: check if 0 is a good default return value in the case z_i==z_o!
        return (std::isnan(result) || std::isinf(result)) ? double(0) : result;
      }

setBFieldZ()

void setBFieldZ ( const double  bfieldZ = 1.5 )

inline

Set the B-Field value used for pT calculations.

Parameters

bfieldZ

B-Field value to be used

Definition at line 102 of file TwoHitVariables.h.

{ m_BFieldZ = bfieldZ; }

setHits()

void setHits ( const B2Vector3D &  oHit, const B2Vector3D &  iHit  )

inline

Set hits if not given in constructor of if they need to be changed.

Parameters

oHit	B2Vector3D of the outer hit used for calculating the single variables
iHit	B2Vector3D of the inner hit used for calculating the single variables

Definition at line 34 of file TwoHitVariables.h.

      {
        m_oHit = oHit;
        m_iHit = iHit;
      }

Member Data Documentation

m_BFieldZ

double m_BFieldZ = 1.5

private

BField along z to estimate pT.

Definition at line 106 of file TwoHitVariables.h.

m_iHit

B2Vector3D m_iHit

private

innermost hit position

Definition at line 110 of file TwoHitVariables.h.

m_oHit

B2Vector3D m_oHit

private

outermost hit position

Definition at line 108 of file TwoHitVariables.h.

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

• tracking/vxdHoughTracking/filters/pathFilters/include/TwoHitVariables.h