KFStrip1DUpdator Class Reference

#include <KFStrip1DUpdator.h>

Inheritance diagram for KFStrip1DUpdator:

List of all members.

Public Member Functions
virtual KFStrip1DUpdator *	clone () const
	KFStrip1DUpdator ()
virtual TSOS	update (const TSOS &aTsos, const TransientTrackingRecHit &aHit) const
	~KFStrip1DUpdator ()
Private Types
typedef LocalTrajectoryError	LTE
typedef LocalTrajectoryParameters	LTP
typedef TrajectoryStateOnSurface	TSOS

---

Detailed Description

A Kalman Updator that works in the measurement frame and uses only the X coordinate (the one perpendicular to the strip). Ported from ORCA.

Date:

2007/05/09 13:50:25

Revision:

1.3

Author:

todorov, cerati

Definition at line 15 of file KFStrip1DUpdator.h.

---

Member Typedef Documentation

typedef LocalTrajectoryError KFStrip1DUpdator::LTE [private]

Definition at line 21 of file KFStrip1DUpdator.h.

typedef LocalTrajectoryParameters KFStrip1DUpdator::LTP [private]

Definition at line 20 of file KFStrip1DUpdator.h.

typedef TrajectoryStateOnSurface KFStrip1DUpdator::TSOS [private]

Definition at line 19 of file KFStrip1DUpdator.h.

---

Constructor & Destructor Documentation

KFStrip1DUpdator::KFStrip1DUpdator

(

)

[inline]

Definition at line 25 of file KFStrip1DUpdator.h.

Referenced by clone().

{}

KFStrip1DUpdator::~KFStrip1DUpdator

(

)

[inline]

Definition at line 27 of file KFStrip1DUpdator.h.

{}

---

Member Function Documentation

virtual KFStrip1DUpdator* KFStrip1DUpdator::clone

(

void

)

const [inline, virtual]

Implements TrajectoryStateUpdator.

Definition at line 31 of file KFStrip1DUpdator.h.

References KFStrip1DUpdator().

  {
    return new KFStrip1DUpdator(*this);
  }

TrajectoryStateOnSurface KFStrip1DUpdator::update	(	const TSOS &	aTsos,
		const TransientTrackingRecHit &	aHit
	)		const [virtual]

Implements TrajectoryStateUpdator.

Definition at line 5 of file KFStrip1DUpdator.cc.

References funct::C, TrajectoryStateOnSurface::globalParameters(), Strip1DMeasurementTransformator::hitError(), Strip1DMeasurementTransformator::hitParameters(), Exhume::I, TrajectoryStateOnSurface::localParameters(), m, GlobalTrajectoryParameters::magneticField(), Strip1DMeasurementTransformator::projectedTrajectoryError(), Strip1DMeasurementTransformator::projectedTrajectoryParameters(), Strip1DMeasurementTransformator::projectionMatrix(), LocalTrajectoryParameters::pzSign(), dttmaxenums::R, TrajectoryStateOnSurface::surface(), TrajectoryStateOnSurface::surfaceSide(), Strip1DMeasurementTransformator::trajectoryError(), Strip1DMeasurementTransformator::trajectoryParameters(), and ExpressReco_HICollisions_FallBack::x.

Referenced by KFSwitching1DUpdator::update().

                                                                                     {

  double pzSign = aTsos.localParameters().pzSign();

  Strip1DMeasurementTransformator myTrafo(aTsos, aHit);

  double m = myTrafo.hitParameters();
  AlgebraicVector5 x(myTrafo.trajectoryParameters());
  double px = myTrafo.projectedTrajectoryParameters();
  
  AlgebraicMatrix15 H(myTrafo.projectionMatrix());
  double V = myTrafo.hitError();
  AlgebraicSymMatrix55 C(myTrafo.trajectoryError());
  double pC = myTrafo.projectedTrajectoryError();

  double R = 1./(V + pC);
  
  // Compute Kalman gain matrix
  AlgebraicMatrix51 K(R * (C * ROOT::Math::Transpose(H)));

  // Compute local filtered state vector
  AlgebraicVector5 fsv = x + K.Col(0) * (m - px);

  // Compute covariance matrix of local filtered state vector
  AlgebraicSymMatrix55 I = AlgebraicMatrixID();
  AlgebraicMatrix55 M = I - K * H;
  AlgebraicSymMatrix55 fse = ROOT::Math::Similarity(M, C) +  ROOT::Math::Similarity(K, AlgebraicSymMatrix11(V) );
//   AlgebraicMatrix M((I - K * H)*C);            // already commented when CLHEP was in use
//   AlgebraicSymMatrix fse(5,0); fse.assign(M);  // already commented when CLHEP was in use

  return TSOS( LTP(fsv, pzSign), LTE(fse), aTsos.surface(), &(aTsos.globalParameters().magneticField()), aTsos.surfaceSide() );  
}