Trk::Chi2TrackCompatibilityEstimator Class Reference

This object reweights the tracks according to a chi2 value constructed according to the distance to the vertex (the error of the vertex is not considered in constructing the chi squared, because this is an apriori probability which enters the fit) More...

#include <Chi2TrackCompatibilityEstimator.h>

Inheritance diagram for Trk::Chi2TrackCompatibilityEstimator:

Collaboration diagram for Trk::Chi2TrackCompatibilityEstimator:

Public Member Functions
virtual StatusCode	initialize () override
virtual StatusCode	finalize () override
virtual void	estimate (VxTrackAtVertex &, const Amg::Vector3D &vertex) const override
	Estimate method changing the state of VxTrackAtVertex.
virtual float	compatibility (VxTrackAtVertex &vtxTrack, const Amg::Vector3D &vertex) const override
	Compatibility method returning the compatibility value.

Private Member Functions
template<class T>
float	_compatibility (T &plane, const Amg::Vector3D &vertex) const
	Compatibility method returning the compatibility value.

Detailed Description

This object reweights the tracks according to a chi2 value constructed according to the distance to the vertex (the error of the vertex is not considered in constructing the chi squared, because this is an apriori probability which enters the fit)

Author

N. Giacinto Piacquadio (for the Freiburg Group)

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Changes:

David Shope david.nosp@m..ric.nosp@m.hard..nosp@m.shop.nosp@m.e@cer.nosp@m.n.ch (2016-03-18) EDM Migration to xAOD - move Trk::Vertex to Amg::Vector3D

Definition at line 33 of file Chi2TrackCompatibilityEstimator.h.

Member Function Documentation

_compatibility()

template<class T>

float Trk::Chi2TrackCompatibilityEstimator::_compatibility ( T & plane, const Amg::Vector3D & vertex ) const

private

Compatibility method returning the compatibility value.

Definition at line 42 of file Chi2TrackCompatibilityEstimator.cxx.

                                                                                                                          {
 
    ATH_MSG_VERBOSE ("Given plane: " << myAtaPlane->associatedSurface() );
 
    //now, once you have the AtaPlane, project the actual vertex on the plane.
    Amg::RotationMatrix3D myPlaneRotation=myAtaPlane->associatedSurface().transform().rotation();
    Amg::Vector3D myTranslation=myAtaPlane->associatedSurface().transform().translation();
 
    //get the x and y direction of the plane
    Amg::Vector3D myXdirPlane=myPlaneRotation.col(0);
    Amg::Vector3D myYdirPlane=myPlaneRotation.col(1);
    //CLHEP::Hep3Vector myZdirPlane=myRotation.colZ();
 
    #ifdef Chi2TrackCompatibilityEstimator_DEBUG
    std::cout << std::setprecision(10) << "Chi2TrackCompatibilityEstimator: " << "Position is: " << vertex << std::endl;
    std::cout << std::setprecision(10) << "Chi2TrackCompatibilityEstimator: " << "Rotation is: " << myPlaneRotation << std::endl;
    std::cout << std::setprecision(10) << "Chi2TrackCompatibilityEstimator: " << "Norm of colX() is: " << myXdirPlane.mag() << " of colY() is: " << myYdirPlane.mag() << std::endl;
    std::cout << std::setprecision(10) << "Chi2TrackCompatibilityEstimator: " << "Translation is: " << myTranslation << std::endl;
    #endif
 
    Amg::Vector3D vertexMinusCenter=vertex-myTranslation;
 
    #ifdef Chi2TrackCompatibilityEstimator_DEBUG
    std::cout << std::setprecision(10) << "Chi2TrackCompatibilityEstimator: " << "VertexMinusCenter: " << vertexMinusCenter << std::endl;
    #endif
 
    Amg::Vector2D myVertexlocXlocY;
    myVertexlocXlocY[0]=vertexMinusCenter.dot(myXdirPlane);
    myVertexlocXlocY[1]=vertexMinusCenter.dot(myYdirPlane);
 
    #ifdef Chi2TrackCompatibilityEstimator_DEBUG
    std::cout << std::setprecision(10) << "Chi2TrackCompatibilityEstimator: " << "Vertex local coordinates: " << myVertexlocXlocY << std::endl;
    #endif
 
    /* ******Maybe this can be still helpfull
    //create a default xy plane
    Plane3D trackPlane();
    
    //rotate and traslate it according to the plane associated to MeasuredAtaPlane
    trackPlane.transform(myAtaPlane->associatedSurface()->transform());
    
    //now project the vertex onto the plane
    Point3D theVertexOnPlane=trackPlane.point(Point3D(vertex.x(),vertex.y(),vertex.z()));
    
    //now express the point found in local coordinates
    */
 
    const AmgSymMatrix(5) * covar = (myAtaPlane->covariance());
    AmgSymMatrix(2) myWeightXY = (*covar).block<2,2>(0,0);
    myWeightXY = myWeightXY.inverse().eval();
 
    Amg::Vector2D myXY;
    myXY[0]=myAtaPlane->parameters()[Trk::locX]-myVertexlocXlocY[0];
    myXY[1]=myAtaPlane->parameters()[Trk::locY]-myVertexlocXlocY[1];
 
    #ifdef Chi2TrackCompatibilityEstimator_DEBUG
    std::cout << std::setprecision(10) << "Chi2TrackCompatibilityEstimator: " << "Parameters local coordinates: " << " x: " <<myAtaPlane->parameters()[Trk::locX] <<
      " y: " << myAtaPlane->parameters()[Trk::locY] << std::endl;
    std::cout << std::setprecision(10) << "Chi2TrackCompatibilityEstimator: " << "VertexToTrack coordinates: " << myXY << std::endl;
    #endif
 
    ATH_MSG_DEBUG ("The weight assigned to the track is " << myXY.dot(myWeightXY*myXY) );
    ATH_MSG_VERBOSE ("coming from X: " << myXY[0] << " and error: "
        << std::sqrt((*(myAtaPlane->covariance()))(Trk::locX,Trk::locX)));
    ATH_MSG_VERBOSE ("and from z0: " << myXY[1] << " and error: "
        << std::sqrt((*(myAtaPlane->covariance()))(Trk::locY,Trk::locY)));
 
    return myXY.dot(myWeightXY*myXY);
  }

compatibility()

float Trk::Chi2TrackCompatibilityEstimator::compatibility ( VxTrackAtVertex & vtxTrack, const Amg::Vector3D & vertex ) const

overridevirtual

Compatibility method returning the compatibility value.

Definition at line 113 of file Chi2TrackCompatibilityEstimator.cxx.

  {
    //Looking for a AtaPlane object (track)
    const Trk::AtaPlane * myAtaPlane=vtxTrack.ImpactPoint3dAtaPlane();
    if (myAtaPlane!=nullptr && myAtaPlane->covariance()!=nullptr) {
      return _compatibility(myAtaPlane, vertex);
    }
 
    //looking for a NeutralAtaPlane object (neutral)
    const Trk::NeutralAtaPlane * myNeutralAtaPlane=vtxTrack.ImpactPoint3dNeutralAtaPlane();
    if (myNeutralAtaPlane!=nullptr && myNeutralAtaPlane->covariance()!=nullptr){
      return _compatibility(myNeutralAtaPlane, vertex);
    }
    
    ATH_MSG_WARNING( " No compatibility plane attached to the VxTrackAtVertex. Compatibility couldn't be found... 0 compatibility returned."  );
    return 100;
  }

estimate()

void Trk::Chi2TrackCompatibilityEstimator::estimate ( VxTrackAtVertex & vtxTrack, const Amg::Vector3D & vertex ) const

overridevirtual

Estimate method changing the state of VxTrackAtVertex.

Definition at line 36 of file Chi2TrackCompatibilityEstimator.cxx.

  {
    vtxTrack.setVtxCompatibility(compatibility(vtxTrack,vertex));
  }

finalize()

StatusCode Trk::Chi2TrackCompatibilityEstimator::finalize ( )

overridevirtual

Definition at line 29 of file Chi2TrackCompatibilityEstimator.cxx.

  {
    ATH_MSG_DEBUG( "Finalize successful"  );
    return StatusCode::SUCCESS;
  }

initialize()

StatusCode Trk::Chi2TrackCompatibilityEstimator::initialize ( )

overridevirtual

Definition at line 23 of file Chi2TrackCompatibilityEstimator.cxx.

  { 
    ATH_MSG_DEBUG( "Initialize successful"  );
    return StatusCode::SUCCESS;
  }

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

• Chi2TrackCompatibilityEstimator.h
• Chi2TrackCompatibilityEstimator.cxx