TwoTrackMinimumDistance Class Reference

#include <TwoTrackMinimumDistance.h>

Inheritance diagram for TwoTrackMinimumDistance:

Public Types
enum	Mode { FastMode = 0, SlowMode = 1 }

Public Member Functions
bool	calculate (const FreeTrajectoryState &sta, const FreeTrajectoryState &stb) override
virtual bool	calculate (const GlobalTrajectoryParameters &sta, const GlobalTrajectoryParameters &stb)
bool	calculate (const TrajectoryStateOnSurface &sta, const TrajectoryStateOnSurface &stb) override
TwoTrackMinimumDistance *	clone () const override
GlobalPoint	crossingPoint () const override
float	distance () const override
double	firstAngle () const
std::pair< double, double >	pathLength () const
std::pair< GlobalPoint, GlobalPoint >	points () const override
double	secondAngle () const
bool	status () const override
	TwoTrackMinimumDistance (const Mode m=FastMode)
	~TwoTrackMinimumDistance () override
Public Member Functions inherited from ClosestApproachOnHelices
	ClosestApproachOnHelices ()
virtual	~ClosestApproachOnHelices ()

Private Types
enum	Charge { hh, hl, ll }

Private Member Functions
bool	pointsHelixHelix (const GlobalTrajectoryParameters &sta, const GlobalTrajectoryParameters &stb)
bool	pointsHelixLine (const GlobalTrajectoryParameters &sta, const GlobalTrajectoryParameters &stb)
bool	pointsLineLine (const GlobalTrajectoryParameters &sta, const GlobalTrajectoryParameters &stb)

Private Attributes
std::pair< GlobalPoint, GlobalPoint >	points_
bool	status_
Charge	theCharge
ClosestApproachInRPhi	theIniAlgo
Mode	theModus
TwoTrackMinimumDistanceHelixHelix	theTTMDhh
TwoTrackMinimumDistanceHelixLine	theTTMDhl
TwoTrackMinimumDistanceLineLine	theTTMDll

Detailed Description

General interface to calculate the PCA of two tracks. According to the charge of the tracks, the correct algorithm is used:

• charged-charged: TwoTrackMinimumDistanceHelixHelix
• charged-neutral: TwoTrackMinimumDistanceHelixLine
• neutral-neutral: TwoTrackMinimumDistanceLineLine

Definition at line 20 of file TwoTrackMinimumDistance.h.

Member Enumeration Documentation

Charge

enum TwoTrackMinimumDistance::Charge

private

Enumerator
hh
hl
ll

Definition at line 60 of file TwoTrackMinimumDistance.h.

{ hh, hl, ll };

Mode

enum TwoTrackMinimumDistance::Mode

Enumerator
FastMode
SlowMode

Definition at line 22 of file TwoTrackMinimumDistance.h.

{ FastMode = 0, SlowMode = 1 };

Constructor & Destructor Documentation

TwoTrackMinimumDistance()

TwoTrackMinimumDistance::TwoTrackMinimumDistance ( const Mode  m = FastMode )

inline

Definition at line 24 of file TwoTrackMinimumDistance.h.

                                                   {
    theModus = m;
    status_ = false;
  };

References visualization-live-secondInstance_cfg::m, status_, and theModus.

Referenced by clone().

~TwoTrackMinimumDistance()

TwoTrackMinimumDistance::~TwoTrackMinimumDistance ( )

inlineoverride

Definition at line 28 of file TwoTrackMinimumDistance.h.

{}

Member Function Documentation

calculate() [1/3]

bool TwoTrackMinimumDistance::calculate ( const FreeTrajectoryState &  sta, const FreeTrajectoryState &  stb  )

overridevirtual

Implements ClosestApproachOnHelices.

Definition at line 87 of file TwoTrackMinimumDistance.cc.

                                                                                                      {
  //  pair<GlobalPoint, GlobalPoint> ret  = theIniAlgo.points ( sta, stb );
  return calculate(sta.parameters(), stb.parameters());
}

References FreeTrajectoryState::parameters().

calculate() [2/3]

bool TwoTrackMinimumDistance::calculate ( const GlobalTrajectoryParameters &  sta, const GlobalTrajectoryParameters &  stb  )

virtual

Definition at line 92 of file TwoTrackMinimumDistance.cc.

                                                                                                                    {
  bool isHelixA = (sta.magneticField().inTesla(sta.position()).z() != 0.) && sta.charge() != 0.;
  bool isHelixB = (stb.magneticField().inTesla(stb.position()).z() != 0.) && stb.charge() != 0.;
  if (!isHelixA && !isHelixB) {
    status_ = pointsLineLine(sta, stb);
  } else if (isHelixA && isHelixB) {
    status_ = pointsHelixHelix(sta, stb);
  } else {
    status_ = pointsHelixLine(sta, stb);
  }
  return status_;
}

References GlobalTrajectoryParameters::charge(), MagneticField::inTesla(), GlobalTrajectoryParameters::magneticField(), and GlobalTrajectoryParameters::position().

calculate() [3/3]

bool TwoTrackMinimumDistance::calculate ( const TrajectoryStateOnSurface &  sta, const TrajectoryStateOnSurface &  stb  )

overridevirtual

Implements ClosestApproachOnHelices.

Definition at line 83 of file TwoTrackMinimumDistance.cc.

                                                                                                                {
  return calculate(sta.globalParameters(), stb.globalParameters());
}

References TrajectoryStateOnSurface::globalParameters().

Referenced by btagbtvdeep::TrackPairInfoBuilder::buildTrackPairInfo(), BPHWriteSpecificDecay::fill(), CrossingPtBasedLinearizationPointFinder::getLinearizationPoint(), PFDisplacedVertexCandidateFinder::link(), TracksClusteringFromDisplacedSeed::nearTracks(), TSCBLBuilderNoMaterial::operator()(), Onia2MuMuPAT::produce(), and CrossingPtBasedLinearizationPointFinder::useAllTracks().

clone()

TwoTrackMinimumDistance* TwoTrackMinimumDistance::clone ( void  ) const

inlineoverridevirtual

Clone method

Implements ClosestApproachOnHelices.

Definition at line 53 of file TwoTrackMinimumDistance.h.

{ return new TwoTrackMinimumDistance(*this); }

References TwoTrackMinimumDistance().

crossingPoint()

GlobalPoint TwoTrackMinimumDistance::crossingPoint ( ) const

overridevirtual

arithmetic mean of the two points of closest approach

Implements ClosestApproachOnHelices.

Definition at line 187 of file TwoTrackMinimumDistance.cc.

{ return mean(points_); }

References SiStripPI::mean.

Referenced by btagbtvdeep::TrackPairInfoBuilder::buildTrackPairInfo(), PFDisplacedVertexCandidateFinder::link(), and TracksClusteringFromDisplacedSeed::nearTracks().

distance()

float TwoTrackMinimumDistance::distance ( ) const

overridevirtual

distance between the two points of closest approach in 3D

Implements ClosestApproachOnHelices.

Definition at line 189 of file TwoTrackMinimumDistance.cc.

{ return dist(points_); }

Referenced by btagbtvdeep::TrackPairInfoBuilder::buildTrackPairInfo(), PFDisplacedVertexCandidateFinder::link(), and TracksClusteringFromDisplacedSeed::nearTracks().

firstAngle()

double TwoTrackMinimumDistance::firstAngle

(

)

const

Definition at line 18 of file TwoTrackMinimumDistance.cc.

                                                 {
  if (!status_)
    throw cms::Exception(
        "TrackingTools/PatternTools",
        "TwoTrackMinimumDistance::could not compute track crossing. Check status before calling this method!");
  switch (theCharge) {
    case (hh):
      return theTTMDhh.firstAngle();
      break;
    case (hl):
      return theTTMDhl.firstAngle();
      break;
    case (ll):
      return theTTMDll.firstAngle();
      break;
  }
  return 0;
}

References Exception, and AlignmentTrackSelector_cfi::theCharge.

Referenced by TSCBLBuilderNoMaterial::operator()().

pathLength()

pair< double, double > TwoTrackMinimumDistance::pathLength

(

)

const

Definition at line 56 of file TwoTrackMinimumDistance.cc.

                                                               {
  if (!status_)
    throw cms::Exception(
        "TrackingTools/PatternTools",
        "TwoTrackMinimumDistance::could not compute track crossing. Check status before calling this method!");
  switch (theCharge) {
    case (hh):
      return theTTMDhh.pathLength();
      break;
    case (hl):
      return theTTMDhl.pathLength();
      break;
    case (ll):
      return theTTMDll.pathLength();
      break;
  }
  return std::pair<double, double>(0, 0);
}

References Exception, and AlignmentTrackSelector_cfi::theCharge.

Referenced by TSCBLBuilderNoMaterial::operator()().

points()

pair< GlobalPoint, GlobalPoint > TwoTrackMinimumDistance::points ( ) const

overridevirtual

Returns the two PCA on the trajectories.

Implements ClosestApproachOnHelices.

Definition at line 75 of file TwoTrackMinimumDistance.cc.

                                                                     {
  if (!status_)
    throw cms::Exception(
        "TrackingTools/PatternTools",
        "TwoTrackMinimumDistance::could not compute track crossing. Check status before calling this method!");
  return points_;
}

References Exception.

Referenced by btagbtvdeep::TrackPairInfoBuilder::buildTrackPairInfo(), BPHWriteSpecificDecay::fill(), CrossingPtBasedLinearizationPointFinder::getLinearizationPoint(), TracksClusteringFromDisplacedSeed::nearTracks(), TSCBLBuilderNoMaterial::operator()(), Onia2MuMuPAT::produce(), and CrossingPtBasedLinearizationPointFinder::useAllTracks().

pointsHelixHelix()

bool TwoTrackMinimumDistance::pointsHelixHelix ( const GlobalTrajectoryParameters &  sta, const GlobalTrajectoryParameters &  stb  )

private

Definition at line 123 of file TwoTrackMinimumDistance.cc.

                                                                                      {
  if ((sta.position() - stb.position()).mag2() < 1e-7f && (sta.momentum() - stb.momentum()).mag2() < 1e-7f &&
      sta.charge() == stb.charge()) {
    edm::LogWarning("TwoTrackMinimumDistance") << "comparing track with itself!";
  };
 
  theCharge = hh;
  if (theModus == FastMode) {
    // first we try directly - in FastMode only ...
    if (!(theTTMDhh.calculate(sta, stb, .0001))) {
      points_ = theTTMDhh.points();
      return true;
    };
  };
 
  // okay. did not work. so we use CAIR, and then TTMD again.
  bool cairStat = theIniAlgo.calculate(sta, stb);
 
  if (!cairStat) {  // yes. CAIR may fail.
    edm::LogWarning("TwoTrackMinimumDistance") << "Computation HelixHelix::CAIR failed.";
    if (theModus == SlowMode) {  // we can still try ttmd here.
      if (!(theTTMDhh.calculate(sta, stb, .0001))) {
        points_ = theTTMDhh.points();
        return true;
      }
    };
    // we can try with more sloppy settings
    if (!(theTTMDhh.calculate(sta, stb, .1))) {
      points_ = theTTMDhh.points();
      return true;
    }
    return false;
    edm::LogWarning("TwoTrackMinimumDistance") << "TwoTrackMinimumDistanceHelixHelix failed";
  };
 
  pair<GlobalTrajectoryParameters, GlobalTrajectoryParameters> ini = theIniAlgo.trajectoryParameters();
 
  pair<GlobalPoint, GlobalPoint> inip(ini.first.position(), ini.second.position());
  bool isFirstALine = ini.first.charge() == 0. || ini.first.magneticField().inTesla(ini.first.position()).z() == 0.;
  bool isSecondALine = ini.second.charge() == 0. || ini.second.magneticField().inTesla(ini.second.position()).z() == 0.;
  bool gotDist = false;
  if (!isFirstALine && !isSecondALine)
    gotDist = theTTMDhh.calculate(ini.first, ini.second, .0001);
  else if (isFirstALine && isSecondALine)
    gotDist = theTTMDll.calculate(ini.first, ini.second);
  else
    gotDist = theTTMDhl.calculate(ini.first, ini.second, .0001);
  if (gotDist) {
    points_ = inip;
  } else {
    if (!isFirstALine && !isSecondALine)
      points_ = theTTMDhh.points();
    else if (isFirstALine && isSecondALine)
      points_ = theTTMDll.points();
    else
      points_ = theTTMDhl.points();
    // if we are still worse than CAIR, we use CAIR results.
    if (dist(points_) > dist(inip))
      points_ = inip;
  };
  return true;
}

References GlobalTrajectoryParameters::charge(), MillePedeFileConverter_cfg::e, f, mag2(), GlobalTrajectoryParameters::momentum(), GlobalTrajectoryParameters::position(), and AlignmentTrackSelector_cfi::theCharge.

pointsHelixLine()

bool TwoTrackMinimumDistance::pointsHelixLine ( const GlobalTrajectoryParameters &  sta, const GlobalTrajectoryParameters &  stb  )

private

Definition at line 114 of file TwoTrackMinimumDistance.cc.

                                                                                     {
  theCharge = hl;
  if (theTTMDhl.calculate(sta, stb, 0.000001))
    return false;
  points_ = theTTMDhl.points();
  return true;
}

References AlignmentTrackSelector_cfi::theCharge.

pointsLineLine()

bool TwoTrackMinimumDistance::pointsLineLine ( const GlobalTrajectoryParameters &  sta, const GlobalTrajectoryParameters &  stb  )

private

Definition at line 105 of file TwoTrackMinimumDistance.cc.

                                                                                    {
  theCharge = ll;
  if (theTTMDll.calculate(sta, stb))
    return false;
  points_ = theTTMDll.points();
  return true;
}

References AlignmentTrackSelector_cfi::theCharge.

secondAngle()

double TwoTrackMinimumDistance::secondAngle

(

)

const

Definition at line 37 of file TwoTrackMinimumDistance.cc.

                                                  {
  if (!status_)
    throw cms::Exception(
        "TrackingTools/PatternTools",
        "TwoTrackMinimumDistance::could not compute track crossing. Check status before calling this method!");
  switch (theCharge) {
    case (hh):
      return theTTMDhh.secondAngle();
      break;
    case (hl):
      return theTTMDhl.secondAngle();
      break;
    case (ll):
      return theTTMDll.secondAngle();
      break;
  }
  return 0;
}

References Exception, and AlignmentTrackSelector_cfi::theCharge.

status()

bool TwoTrackMinimumDistance::status ( void  ) const

inlineoverridevirtual

Implements ClosestApproachOnHelices.

Definition at line 36 of file TwoTrackMinimumDistance.h.

{ return status_; }

References status_.

Member Data Documentation

points_

std::pair<GlobalPoint, GlobalPoint> TwoTrackMinimumDistance::points_

private

Definition at line 68 of file TwoTrackMinimumDistance.h.

status_

bool TwoTrackMinimumDistance::status_

private

Definition at line 67 of file TwoTrackMinimumDistance.h.

Referenced by status(), and TwoTrackMinimumDistance().

theCharge

Charge TwoTrackMinimumDistance::theCharge

private

Definition at line 62 of file TwoTrackMinimumDistance.h.

theIniAlgo

ClosestApproachInRPhi TwoTrackMinimumDistance::theIniAlgo

private

Definition at line 63 of file TwoTrackMinimumDistance.h.

theModus

Mode TwoTrackMinimumDistance::theModus

private

Definition at line 61 of file TwoTrackMinimumDistance.h.

Referenced by TwoTrackMinimumDistance().

theTTMDhh

TwoTrackMinimumDistanceHelixHelix TwoTrackMinimumDistance::theTTMDhh

private

Definition at line 64 of file TwoTrackMinimumDistance.h.

theTTMDhl

TwoTrackMinimumDistanceHelixLine TwoTrackMinimumDistance::theTTMDhl

private

Definition at line 66 of file TwoTrackMinimumDistance.h.

theTTMDll

TwoTrackMinimumDistanceLineLine TwoTrackMinimumDistance::theTTMDll

private

Definition at line 65 of file TwoTrackMinimumDistance.h.