SmartPointingConstraint Class Reference

#include <SmartPointingConstraint.h>

Inheritance diagram for SmartPointingConstraint:

Public Member Functions
virtual SmartPointingConstraint *	clone () const
virtual std::pair < AlgebraicMatrix, AlgebraicVector >	derivative (const AlgebraicVector &exPoint) const
virtual std::pair < AlgebraicMatrix, AlgebraicVector >	derivative (const std::vector< RefCountedKinematicParticle > &par) const
virtual AlgebraicVector	deviations (int nStates) const
virtual int	numberOfEquations () const
	SmartPointingConstraint (const GlobalPoint &ref)
virtual std::pair < AlgebraicVector, AlgebraicVector >	value (const AlgebraicVector &exPoint) const
virtual std::pair < AlgebraicVector, AlgebraicVector >	value (const std::vector< RefCountedKinematicParticle > &par) const
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 21 of file SmartPointingConstraint.h.

Constructor & Destructor Documentation

SmartPointingConstraint::SmartPointingConstraint ( const GlobalPoint &  ref )

inline

Definition at line 25 of file SmartPointingConstraint.h.

Referenced by clone().

                                                 :refPoint(ref)
  {}

Member Function Documentation

virtual SmartPointingConstraint* SmartPointingConstraint::clone ( ) const

inlinevirtual

Clone method

Implements KinematicConstraint.

Definition at line 53 of file SmartPointingConstraint.h.

References SmartPointingConstraint().

 {return new SmartPointingConstraint(*this);}

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

virtual

Implements KinematicConstraint.

Definition at line 25 of file SmartPointingConstraint.cc.

References 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);
}

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

virtual

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

Implements KinematicConstraint.

Definition at line 43 of file SmartPointingConstraint.cc.

References 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);
// cout<<"Derivative returned: "<<dr<<endl;
// cout<<"For the value: "<<lPoint<<endl;
 return std::pair<AlgebraicMatrix,AlgebraicVector>(dr,lPoint);
}

AlgebraicVector SmartPointingConstraint::deviations ( int  nStates ) const

virtual

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 75 of file SmartPointingConstraint.cc.

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

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

private

Definition at line 116 of file SmartPointingConstraint.cc.

References point, funct::pow(), 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);
 
//angular functuions:

//half angle solution
//d/dx_i
 dr(1,1) = (dy*(dx*px + dy*py))/(pow(pow(dx,2) + pow(dy,2),1.5)*sqrt(pow(px,2) + pow(py,2))) ;
    
 dr(1,2) = -((dx*(dx*px + dy*py))/(pow(pow(dx,2) + pow(dy,2),1.5)*sqrt(pow(px,2) + pow(py,2)))) ;
 
 dr(1,3) = 0;
 
//d/dp_i  
//debug: x->p index xhange in denominator
 dr(1,4) = -((py*(dx*px + dy*py))/(sqrt(pow(dx,2) + pow(dy,2))*pow(pow(px,2) + pow(py,2),1.5)));
               
 dr(1,5) = (px*(dx*px + dy*py))/(sqrt(pow(dx,2) + pow(dy,2))*pow(pow(px,2) + pow(py,2),1.5));
 
 dr(1,6) = 0;
 dr(1,7) = 0; 

//2nd equation
//d/dx_i

 dr(2,1) = (dx*dz*(sqrt(pow(dx,2) + pow(dy,2))*sqrt(pow(px,2) + pow(py,2)) + dz*pz))/
           (sqrt(pow(dx,2) + pow(dy,2))*pow(pow(dx,2) + pow(dy,2) + pow(dz,2),1.5)*
            sqrt(pow(px,2) + pow(py,2) + pow(pz,2)));
           
 dr(2,2) = (dy*dz*(sqrt(pow(dx,2) + pow(dy,2))*sqrt(pow(px,2) + pow(py,2)) + dz*pz))/
           (sqrt(pow(dx,2) + pow(dy,2))*pow(pow(dx,2) + pow(dy,2) + pow(dz,2),1.5)*
            sqrt(pow(px,2) + pow(py,2) + pow(pz,2)));
           
    
 dr(2,3) = (-((pow(dx,2) + pow(dy,2))*sqrt(pow(px,2) + pow(py,2))) - sqrt(pow(dx,2) + pow(dy,2))*dz*pz)/
           (pow(pow(dx,2) + pow(dy,2) + pow(dz,2),1.5)*sqrt(pow(px,2) + pow(py,2) + pow(pz,2)));
           

 
//d/dp_i 
//debug: x->p index xhange in denominator

 dr(2,4) = -((px*pz*(sqrt(pow(dx,2) + pow(dy,2))*sqrt(pow(px,2) + pow(py,2)) + dz*pz))/
            (sqrt(pow(dx,2) + pow(dy,2) + pow(dz,2))*sqrt(pow(px,2) + pow(py,2))*
             pow(pow(px,2) + pow(py,2) + pow(pz,2),1.5)));
 
 dr(2,5) = -((py*pz*(sqrt(pow(dx,2) + pow(dy,2))*sqrt(pow(px,2) + pow(py,2)) + dz*pz))/
            (sqrt(pow(dx,2) + pow(dy,2) + pow(dz,2))*sqrt(pow(px,2) + pow(py,2))*
            pow(pow(px,2) + pow(py,2) + pow(pz,2),1.5))) ;
 
 dr(2,6) = (sqrt(pow(dx,2) + pow(dy,2))*(pow(px,2) + pow(py,2)) + dz*sqrt(pow(px,2) + pow(py,2))*pz)/
           (sqrt(pow(dx,2) + pow(dy,2) + pow(dz,2))*pow(pow(px,2) + pow(py,2) + pow(pz,2),1.5)) ;
 
 dr(2,7) = 0;
 
// cout<<"derivative matrix "<<dr<<endl;
 return std::pair<AlgebraicMatrix,AlgebraicVector>(dr,point); 
}

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

private

Definition at line 81 of file SmartPointingConstraint.cc.

References point, refPoint, mathSSE::sqrt(), PV3DBase< T, PVType, FrameType >::x(), PV3DBase< T, PVType, FrameType >::y(), and PV3DBase< T, PVType, FrameType >::z().

Referenced by value().

{ 
// cout<<"Make value called"<<endl;
 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);


//full angle solution: sin(alpha - betha) = 0
//sign swap allowed
 double cos_phi_p = px/sqrt(px*px + py*py);
 double sin_phi_p = py/sqrt(px*px + py*py);
 double cos_phi_x = dx/sqrt(dx*dx + dy*dy);
 double sin_phi_x = dy/sqrt(dx*dx + dy*dy);
 
 double sin_theta_p = pz/sqrt(px*px + py*py + pz*pz); 
 double sin_theta_x = dz/sqrt(dx*dx + dy*dy + dz*dz);
 
 double cos_theta_p = sqrt(px*px + py*py)/sqrt(px*px + py*py + pz*pz); 
 double cos_theta_x = sqrt(dx*dx + dy*dy)/sqrt(dx*dx + dy*dy + dz*dz);
 
 float feq = sin_phi_p*cos_phi_x - cos_phi_p*sin_phi_x;
 float seq = sin_theta_p* cos_theta_x - cos_theta_p * sin_theta_x;
 
 vl(1) = feq;
 vl(2) = seq;

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

int SmartPointingConstraint::numberOfEquations ( ) const

virtual

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

Implements KinematicConstraint.

Definition at line 78 of file SmartPointingConstraint.cc.

{return 2;}

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

virtual

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

Implements KinematicConstraint.

Definition at line 5 of file SmartPointingConstraint.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); 
}

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

virtual

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 60 of file SmartPointingConstraint.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);
// cout<<"Value returned: "<<vl<<endl;
// cout<<"For the point: "<<lPoint<<endl;
 
 return std::pair<AlgebraicVector,AlgebraicVector>(vl,lPoint);
}

Member Data Documentation

GlobalPoint SmartPointingConstraint::refPoint

private

Definition at line 61 of file SmartPointingConstraint.h.

Referenced by makeDerivative(), and makeValue().