KalmanTrackToTrackCovCalculator< N > Class Template Reference

#include <KalmanTrackToTrackCovCalculator.h>

Inheritance diagram for KalmanTrackToTrackCovCalculator< N >:

Public Types
typedef CachingVertex< N > ::RefCountedVertexTrack	RefCountedVertexTrack

Public Member Functions
KalmanTrackToTrackCovCalculator *	clone () const override
	KalmanTrackToTrackCovCalculator ()
CachingVertex< N >::TrackToTrackMap	operator() (const CachingVertex< N > &vertex) const override
Public Member Functions inherited from TrackToTrackCovCalculator< N >
	TrackToTrackCovCalculator ()
virtual	~TrackToTrackCovCalculator ()

Detailed Description

template<unsigned int N>
class KalmanTrackToTrackCovCalculator< N >

Calculates all the track-to-track covariance matrices using the Kalman filter algorithms after the vertex has been fit and the tracks refit.

Definition at line 13 of file KalmanTrackToTrackCovCalculator.h.

Member Typedef Documentation

template<unsigned int N>

typedef CachingVertex<N>::RefCountedVertexTrack KalmanTrackToTrackCovCalculator< N >::RefCountedVertexTrack

Definition at line 15 of file KalmanTrackToTrackCovCalculator.h.

Constructor & Destructor Documentation

template<unsigned int N>

KalmanTrackToTrackCovCalculator< N >::KalmanTrackToTrackCovCalculator ( )

inline

Definition at line 17 of file KalmanTrackToTrackCovCalculator.h.

Referenced by KalmanTrackToTrackCovCalculator< N >::clone().

{}

Member Function Documentation

template<unsigned int N>

KalmanTrackToTrackCovCalculator* KalmanTrackToTrackCovCalculator< N >::clone ( void  ) const

inlineoverridevirtual

Implements TrackToTrackCovCalculator< N >.

Definition at line 28 of file KalmanTrackToTrackCovCalculator.h.

References KalmanTrackToTrackCovCalculator< N >::KalmanTrackToTrackCovCalculator().

{ return new KalmanTrackToTrackCovCalculator(*this); }

template<unsigned int N>

CachingVertex< N >::TrackToTrackMap KalmanTrackToTrackCovCalculator< N >::operator() ( const CachingVertex< N > &  vertex ) const

overridevirtual

Calculates all the track-to-track covariance matrices

Parameters

vertex

The vertex whose track-to-track covariance matrices have to be calculated.

Returns

The map containing the covariance matrices.

Implements TrackToTrackCovCalculator< N >.

Definition at line 5 of file KalmanTrackToTrackCovCalculator.cc.

References CachingVertex< N >::error(), mps_fire::i, dqmiolumiharvest::j, GlobalErrorBase< T, ErrorWeightType >::matrix(), N, CachingVertex< N >::tracks(), and tracks.

                                          {
  typedef ROOT::Math::SMatrix<double, N, 3, ROOT::Math::MatRepStd<double, N, 3> > AlgebraicMatrixN3;
  typedef ROOT::Math::SMatrix<double, N, N - 2, ROOT::Math::MatRepStd<double, N, N - 2> > AlgebraicMatrixNM;
  typedef ROOT::Math::SMatrix<double, N - 2, 3, ROOT::Math::MatRepStd<double, N - 2, 3> > AlgebraicMatrixM3;
  typedef ROOT::Math::SMatrix<double, 3, N - 2, ROOT::Math::MatRepStd<double, 3, N - 2> > AlgebraicMatrix3M;
  typedef ROOT::Math::SMatrix<double, N, N, ROOT::Math::MatRepSym<double, N> > AlgebraicSymMatrixNN;
  typedef ROOT::Math::SMatrix<double, N - 2, N - 2, ROOT::Math::MatRepSym<double, N - 2> > AlgebraicSymMatrixMM;
  typedef ROOT::Math::SMatrix<double, N - 2, N - 2, ROOT::Math::MatRepStd<double, N - 2, N - 2> > AlgebraicMatrixMM;

  typename CachingVertex<N>::TrackToTrackMap returnMap;
  int ifail = 0;
  std::vector<RefCountedVertexTrack> tracks = vertex.tracks();

  //vertex initial data needed
  AlgebraicSymMatrix33 vertexC = vertex.error().matrix();

  for (typename std::vector<RefCountedVertexTrack>::iterator i = tracks.begin(); i != tracks.end(); i++) {
    const AlgebraicMatrixN3& leftA = (*i)->linearizedTrack()->positionJacobian();
    const AlgebraicMatrixNM& leftB = (*i)->linearizedTrack()->momentumJacobian();
    AlgebraicSymMatrixNN leftG = (*i)->linearizedTrack()->predictedStateWeight(ifail);
    AlgebraicSymMatrixMM leftW = ROOT::Math::SimilarityT(leftB, leftG);

    ifail = !leftW.Invert();
    if (ifail != 0)
      throw VertexException("KalmanTrackToTrackCovarianceCalculator::leftW matrix inversion failed");
    AlgebraicMatrixM3 leftPart = leftW * (ROOT::Math::Transpose(leftB)) * leftG * leftA;
    typename CachingVertex<N>::TrackMap internalMap;
    for (typename std::vector<RefCountedVertexTrack>::iterator j = tracks.begin(); j != tracks.end(); j++) {
      if (*i < *j) {
        const AlgebraicMatrixN3& rightA = (*j)->linearizedTrack()->positionJacobian();
        const AlgebraicMatrixNM& rightB = (*j)->linearizedTrack()->momentumJacobian();
        AlgebraicSymMatrixNN rightG = (*j)->linearizedTrack()->predictedStateWeight(ifail);
        AlgebraicSymMatrixMM rightW = ROOT::Math::SimilarityT(rightB, rightG);

        ifail = !rightW.Invert();

        if (ifail != 0)
          throw VertexException("KalmanTrackToTrackCovarianceCalculator::rightW matrix inversion failed");
        AlgebraicMatrix3M rightPart = (ROOT::Math::Transpose(rightA)) * rightG * rightB * rightW;
        internalMap[(*j)] = leftPart * vertexC * rightPart;
      }
    }
    returnMap[*i] = internalMap;
  }
  return returnMap;
}