PointingKinematicConstraint Class Reference

#include <PointingKinematicConstraint.h>

Inheritance diagram for PointingKinematicConstraint:

Public Member Functions
PointingKinematicConstraint *	clone () const override
std::pair< AlgebraicMatrix, AlgebraicVector >	derivative (const AlgebraicVector &exPoint) const override
std::pair< AlgebraicMatrix, AlgebraicVector >	derivative (const std::vector< RefCountedKinematicParticle > &par) const override
AlgebraicVector	deviations (int nStates) const override
int	numberOfEquations () const override
	PointingKinematicConstraint (const GlobalPoint &ref)
std::pair< AlgebraicVector, AlgebraicVector >	value (const AlgebraicVector &exPoint) const override
std::pair< AlgebraicVector, AlgebraicVector >	value (const std::vector< RefCountedKinematicParticle > &par) const override
Public Member Functions inherited from KinematicConstraint
	KinematicConstraint ()
virtual	~KinematicConstraint ()

Private Member Functions
std::pair< AlgebraicMatrix, AlgebraicVector >	makeDerivative (const AlgebraicVector &exPoint) const
std::pair< AlgebraicVector, AlgebraicVector >	makeValue (const AlgebraicVector &exPoint) const

Private Attributes
GlobalPoint	refPoint

Detailed Description

Topological constraint making a momentum vector to point to the given location in space. Example: if b-meson momentum is reconstructed at b-meson decay position (secondary vertex), making reconstructed momentum pointing the the primary vertex

Multiple track refit is not supported in current version

Kirill Prokofiev, March 2004 MultiState version: July 2004

Definition at line 19 of file PointingKinematicConstraint.h.

Constructor & Destructor Documentation

PointingKinematicConstraint()

PointingKinematicConstraint::PointingKinematicConstraint ( const GlobalPoint &  ref )

inline

Definition at line 21 of file PointingKinematicConstraint.h.

Referenced by clone().

: refPoint(ref) {}

Member Function Documentation

clone()

PointingKinematicConstraint* PointingKinematicConstraint::clone ( ) const

inlineoverridevirtual

Clone method

Implements KinematicConstraint.

Definition at line 49 of file PointingKinematicConstraint.h.

References PointingKinematicConstraint().

{ return new PointingKinematicConstraint(*this); }

derivative() [1/2]

std::pair< AlgebraicMatrix, AlgebraicVector > PointingKinematicConstraint::derivative ( const AlgebraicVector &  exPoint ) const

overridevirtual

Implements KinematicConstraint.

Definition at line 26 of file PointingKinematicConstraint.cc.

References l1ctLayer1_cff::dr, and makeDerivative().

                                          {
  if (exPoint.num_row() == 0)
    throw VertexException("PointingKinematicConstraint::value requested for zero Linearization point");

  //security check for extended cartesian parametrization
  int inSize = exPoint.num_row();
  if ((inSize % 7) != 0)
    throw VertexException("PointingKinematicConstraint::linearization point has a wrong dimension");
  int nStates = inSize / 7;
  if (nStates != 1)
    throw VertexException("PointingKinematicConstraint::Current version does not support the multistate refit");
  AlgebraicVector lPar = exPoint;

  //2x7 derivative matrix for given particle
  AlgebraicMatrix lDeriv = makeDerivative(lPar).first;
  AlgebraicMatrix dr(2, 7, 0);
  dr.sub(1, 1, lDeriv);
  return std::pair<AlgebraicMatrix, AlgebraicVector>(dr, lPar);
}

derivative() [2/2]

std::pair< AlgebraicMatrix, AlgebraicVector > PointingKinematicConstraint::derivative ( const std::vector< RefCountedKinematicParticle > &  par ) const

overridevirtual

Vector of values and matrix of derivatives calculated using current state parameters as expansion point

Implements KinematicConstraint.

Definition at line 47 of file PointingKinematicConstraint.cc.

References l1ctLayer1_cff::dr, and makeDerivative().

                                                             {
  int nStates = par.size();
  if (nStates == 0)
    throw VertexException("PointingKinematicConstraint::Empty vector of particles passed");
  if (nStates != 1)
    throw VertexException("PointingKinematicConstraint::Current version does not support the multistate refit");

  AlgebraicMatrix dr(2, 7, 0);
  AlgebraicVector lPoint = asHepVector<7>(par.front()->currentState().kinematicParameters().vector());

  //2x7 derivative matrix for given state
  AlgebraicMatrix lDeriv = makeDerivative(lPoint).first;
  dr.sub(1, 1, lDeriv);
  return std::pair<AlgebraicMatrix, AlgebraicVector>(dr, lPoint);
}

deviations()

AlgebraicVector PointingKinematicConstraint::deviations ( int  nStates ) const

overridevirtual

Returns vector of sigma squared associated to the KinematicParameters of refitted particles Initial deviations are given by user for the constraining parameters (mass, momentum components etc). In case of multiple states exactly the same values are added to every particle parameters

Implements KinematicConstraint.

Definition at line 182 of file PointingKinematicConstraint.cc.

{ return AlgebraicVector(7 * nStates, 0); }

makeDerivative()

std::pair< AlgebraicMatrix, AlgebraicVector > PointingKinematicConstraint::makeDerivative ( const AlgebraicVector &  exPoint ) const

private

Definition at line 113 of file PointingKinematicConstraint.cc.

References l1ctLayer1_cff::dr, PVValHelper::dx, PVValHelper::dy, PVValHelper::dz, point, multPhiCorr_741_25nsDY_cfi::px, multPhiCorr_741_25nsDY_cfi::py, refPoint, mathSSE::sqrt(), PV3DBase< T, PVType, FrameType >::x(), PV3DBase< T, PVType, FrameType >::y(), and PV3DBase< T, PVType, FrameType >::z().

Referenced by derivative().

                                          {
  AlgebraicMatrix dr(2, 7, 0);
  AlgebraicVector point = exPoint;
  double dx = point(1) - refPoint.x();
  double dy = point(2) - refPoint.y();
  double dz = point(3) - refPoint.z();
  double px = point(4);
  double py = point(5);
  double pz = point(6);

  // double tr = px*px + py*py;
  // double trd = dx*dx + dy*dy;
  // double pr =1.5;
  // double p_factor = pow(tr,pr);
  // double x_factor = pow(trd,pr);

  //tangent solution
  /*
 dr(1,1) = -dy/(dx*dx);
 dr(1,2) = 1/dx;
 dr(1,3) = 0;
 dr(1,4) = py/(px*px);
 dr(1,5) = -1/px;
 dr(1,6) = 0;
 dr(1,7) = 0;
 
 dr(2,1) = -(dx*dz)/x_factor;
 dr(2,2) = -(dy*dz)/x_factor;
 dr(2,3) = 1/sqrt(dx*dx + dy*dy);
 dr(2,4) = (px*pz)/p_factor;
 dr(2,5) = (py*pz)/p_factor;
 dr(2,6) = -1/sqrt(px*px + py*py);
 dr(2,7) = 0.;
*/
  //half angle solution corrected
  /*
 dr(1,1) = - dy/(dx*dx+dy*dy+dx*sqrt(dx*dx+dy*dy));
 dr(1,2) =   dx/(dx*dx+dy*dy+dx*sqrt(dx*dx+dy*dy));
 dr(1,3) = 0; 
 dr(1,4) = py/(px*px+py*py+px*sqrt(px*px+py*py));
 dr(1,5) = -px/(px*px+py*py+px*sqrt(px*px+py*py));
 dr(1,6) = 0;
 dr(1,7) = 0; 
*/

  //half angle solution
  dr(1, 1) = dx / (dy * sqrt(dx * dx + dy * dy)) - 1 / dy;
  dr(1, 2) = 1 / sqrt(dx * dx + dy * dy) - sqrt(dx * dx + dy * dy) / (dy * dy) + dx / (dy * dy);
  dr(1, 3) = 0;
  dr(1, 4) = -(px / (py * sqrt(px * px + py * py)) - 1 / py);
  dr(1, 5) = -(1 / sqrt(px * px + py * py) - sqrt(px * px + py * py) / (py * py) + px / (py * py));
  dr(1, 6) = 0;
  dr(1, 7) = 0;

  //half angle solution
  dr(2, 1) = (dx / dz) * (1 / sqrt(dx * dx + dy * dy + dz * dz) - 1 / sqrt(dx * dx + dy * dy));
  dr(2, 2) = (dy / dz) * (1 / sqrt(dx * dx + dy * dy + dz * dz) - 1 / sqrt(dx * dx + dy * dy));
  dr(2, 3) = (1 / (dz * dz)) * (sqrt(dx * dx + dy * dy) - sqrt(dx * dx + dy * dy + dz * dz)) +
             1 / sqrt(dx * dx + dy * dy + dz * dz);
  dr(2, 4) = -(px / pz) * (1 / sqrt(px * px + py * py + pz * pz) - 1 / sqrt(px * px + py * py));
  dr(2, 5) = -(py / pz) * (1 / sqrt(px * px + py * py + pz * pz) - 1 / sqrt(px * px + py * py));
  dr(2, 6) = -((1 / (pz * pz)) * (sqrt(px * px + py * py) - sqrt(px * px + py * py + pz * pz)) +
               1 / sqrt(px * px + py * py + pz * pz));
  dr(2, 7) = 0;

  return std::pair<AlgebraicMatrix, AlgebraicVector>(dr, point);
}

makeValue()

std::pair< AlgebraicVector, AlgebraicVector > PointingKinematicConstraint::makeValue ( const AlgebraicVector &  exPoint ) const

private

Definition at line 78 of file PointingKinematicConstraint.cc.

References PVValHelper::dx, PVValHelper::dy, PVValHelper::dz, point, multPhiCorr_741_25nsDY_cfi::px, multPhiCorr_741_25nsDY_cfi::py, refPoint, mathSSE::sqrt(), PV3DBase< T, PVType, FrameType >::x(), PV3DBase< T, PVType, FrameType >::y(), and PV3DBase< T, PVType, FrameType >::z().

Referenced by value().

                                          {
  AlgebraicVector vl(2, 0);
  AlgebraicVector point = exPoint;
  double dx = point(1) - refPoint.x();
  double dy = point(2) - refPoint.y();
  double dz = point(3) - refPoint.z();
  double px = point(4);
  double py = point(5);
  double pz = point(6);

  // tangent solution
  // vl(1) = dy/dx - py/px;
  // vl(2) = dz/sqrt(dx*dx + dy*dy) - pz/sqrt(px*px + py*py);

  //half angle solution
  double sin_p = py / sqrt(px * px + py * py);
  double cos_p = px / sqrt(px * px + py * py);
  double sin_x = dy / sqrt(dx * dx + dy * dy);
  double cos_x = dx / sqrt(dx * dx + dy * dy);

  double sin_pt = pz / sqrt(px * px + py * py + pz * pz);
  double cos_pt = sqrt(px * px + py * py) / sqrt(px * px + py * py + pz * pz);
  double sin_xt = dz / sqrt(dx * dx + dy * dy + dz * dz);
  double cos_xt = sqrt(dx * dx + dy * dy) / sqrt(dx * dx + dy * dy + dz * dz);

  vl(1) = (1 - cos_x) / sin_x - (1 - cos_p) / sin_p;
  vl(2) = (1 - cos_xt) / sin_xt - (1 - cos_pt) / sin_pt;

  //half angle corrected
  // vl(1) = (sin_x/(1+cos_x)) - (sin_p/(1+cos_p));
  // vl(2) = (sin_xt/(1+cos_xt)) - (sin_pt/(1+cos_pt));
  return std::pair<AlgebraicVector, AlgebraicVector>(vl, point);
}

numberOfEquations()

int PointingKinematicConstraint::numberOfEquations ( ) const

overridevirtual

Returns number of constraint equations used for fitting. Method is relevant for proper NDF calculations.

Implements KinematicConstraint.

Definition at line 184 of file PointingKinematicConstraint.cc.

{ return 2; }

value() [1/2]

std::pair< AlgebraicVector, AlgebraicVector > PointingKinematicConstraint::value ( const AlgebraicVector &  exPoint ) const

overridevirtual

Vector of values and matrix of derivatives calculated at given expansion 7xNumberOfStates point

Implements KinematicConstraint.

Definition at line 4 of file PointingKinematicConstraint.cc.

References makeValue().

                                                                                                                 {
  if (exPoint.num_row() == 0)
    throw VertexException("PointingKinematicConstraint::value requested for zero Linearization point");

  //security check for extended cartesian parametrization
  int inSize = exPoint.num_row();
  if ((inSize % 7) != 0)
    throw VertexException("PointingKinematicConstraint::linearization point has a wrong dimension");
  int nStates = inSize / 7;
  if (nStates != 1)
    throw VertexException("PointingKinematicConstraint::Current version does not support the multistate refit");

  AlgebraicVector lPar = exPoint;
  AlgebraicVector vl(2, 0);

  //vector of values 1x2  for given particle
  AlgebraicVector lValue = makeValue(lPar).first;
  vl(1) = lValue(1);
  vl(2) = lValue(2);
  return std::pair<AlgebraicVector, AlgebraicVector>(vl, lPar);
}

value() [2/2]

std::pair< AlgebraicVector, AlgebraicVector > PointingKinematicConstraint::value ( const std::vector< RefCountedKinematicParticle > &  par ) const

overridevirtual

Methods making value and derivative matrix using current state parameters as expansion 7-point. Constraint can be made equaly for single and multiple states

Implements KinematicConstraint.

Definition at line 64 of file PointingKinematicConstraint.cc.

References makeValue().

                                                             {
  int nStates = par.size();
  if (nStates == 0)
    throw VertexException("PointingKinematicConstraint::Empty vector of particles passed");
  if (nStates != 1)
    throw VertexException("PointingKinematicConstraint::Current version does not support the multistate refit");
  AlgebraicVector vl(2, 0);
  AlgebraicVector lPoint = asHepVector<7>(par.front()->currentState().kinematicParameters().vector());
  vl(1) = makeValue(lPoint).first(1);
  vl(2) = makeValue(lPoint).first(2);
  return std::pair<AlgebraicVector, AlgebraicVector>(vl, lPoint);
}

Member Data Documentation

refPoint

GlobalPoint PointingKinematicConstraint::refPoint

private

Definition at line 55 of file PointingKinematicConstraint.h.

Referenced by makeDerivative(), and makeValue().