Helix parameter class. More...

#include <Helix.h>

Inheritance diagram for Helix:

Public Member Functions
	Helix ()

	Helix (const HepPoint3D &pivot, const HepVector &a, const HepSymMatrix &Ea)
	Constructor with pivot, helix parameter a, and its error matrix.

	Helix (const HepPoint3D &pivot, const HepVector &a)
	Constructor without error matrix.

	Helix (const HepPoint3D &position, const Hep3Vector &momentum, double charge)
	Constructor with position, momentum, and charge.

	Helix (const Helix &i)

virtual	~Helix ()
	Destructor.

const HepPoint3D &	center (void) const
	returns position of helix center(z = 0.);

const HepPoint3D &	pivot (void) const
	returns pivot position.

double	radius (void) const
	returns radious of helix.

HepPoint3D	x (double dPhi=0.) const
	returns position after rotating angle dPhi in phi direction.

double *	x (double dPhi, double p[3]) const

HepPoint3D	x (double dPhi, HepSymMatrix &Ex) const
	returns position and convariance matrix(Ex) after rotation.

Hep3Vector	direction (double dPhi=0.) const
	returns direction vector after rotating angle dPhi in phi direction.

Hep3Vector	momentum (double dPhi=0.) const
	returns momentum vector after rotating angle dPhi in phi direction.

Hep3Vector	momentum (double dPhi, HepSymMatrix &Em) const
	returns momentum vector after rotating angle dPhi in phi direction.

HepLorentzVector	momentum (double dPhi, double mass) const
	returns 4momentum vector after rotating angle dPhi in phi direction.

HepLorentzVector	momentum (double dPhi, double mass, HepSymMatrix &Em) const
	returns 4momentum vector after rotating angle dPhi in phi direction.

HepLorentzVector	momentum (double dPhi, double mass, HepPoint3D &x, HepSymMatrix &Emx) const
	returns 4momentum vector after rotating angle dPhi in phi direction.

double	dr (void) const
	returns an element of parameters.

double	phi0 (void) const

double	kappa (void) const

double	dz (void) const

double	tanl (void) const

double	curv (void) const

double	sinPhi0 (void) const

double	cosPhi0 (void) const

double	alpha (void) const

const HepVector &	a (void) const
	returns helix parameters.

const HepSymMatrix &	Ea (void) const
	returns error matrix.

double	pt (void) const

double	cosTheta (void) const

const HepVector &	a (const HepVector &newA)
	sets helix parameters.

const HepSymMatrix &	Ea (const HepSymMatrix &newdA)
	sets helix paramters and error matrix.

const HepPoint3D &	pivot (const HepPoint3D &newPivot)
	sets pivot position.

void	set (const HepPoint3D &pivot, const HepVector &a, const HepSymMatrix &Ea)
	sets helix pivot position, parameters, and error matrix.

void	ignoreErrorMatrix (void)
	unsets error matrix. Error calculations will be ignored after this function call until an error matrix be set again. 0 matrix will be return as a return value for error matrix when you call functions which returns an error matrix.

double	bFieldZ (double)
	sets/returns z componet of the magnetic field.

double	bFieldZ (void) const

Helix &	operator= (const Helix &)
	Copy operator.

HepMatrix	delApDelA (const HepVector &ap) const

HepMatrix	delXDelA (double phi) const

HepMatrix	delMDelA (double phi) const

HepMatrix	del4MDelA (double phi, double mass) const

HepMatrix	del4MXDelA (double phi, double mass) const

double	IntersectCylinder (double r) const

double	flightArc (HepPoint3D &hit) const

double	flightArc (double r) const

double	flightLength (HepPoint3D &hit) const

double	dPhi (HepPoint3D &hit) const

Static Public Attributes
static const double	ConstantAlpha = 333.564095
	Constant alpha for uniform field.

Protected Attributes
IMagneticFieldSvc *	m_pmgnIMF

double	m_bField

double	m_alpha

Detailed Description

Helix parameter class.

Definition at line 53 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

Constructor & Destructor Documentation

◆ Helix() [1/5]

Helix::Helix ( )

Definition at line 47 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

: m_matrixValid(true)
{
  StatusCode scmgn = Gaudi::svcLocator()->service("MagneticFieldSvc",m_pmgnIMF); 
  if(scmgn!=StatusCode::SUCCESS) { 
    std::cout<< "Unable to open Magnetic field service"<<std::endl;
  }
  m_bField = -10000*(m_pmgnIMF->getReferField());//zhangr 2012-09-06 for MagnField
  //m_bField = 10000*(m_pmgnIMF->getReferField());
  m_alpha = 10000. / 2.99792458 / m_bField;
 
  HepPoint3D pivot(0,0,0);
  HepVector a(5,0);
  HepSymMatrix Ea(5,0);
  m_pivot = pivot;
  m_a = a;
  m_Ea = Ea;  
  updateCache();
}

Referenced by Helix(), Helix(), Helix(), Helix(), and Helix().

◆ Helix() [2/5]

Helix::Helix	(	const HepPoint3D &	pivot,
		const HepVector &	a,
		const HepSymMatrix &	Ea )

Constructor with pivot, helix parameter a, and its error matrix.

Definition at line 67 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

  : //m_bField(-10.0),
  //m_alpha(-333.564095),
  m_pivot(pivot),
  m_a(a),
  m_matrixValid(true),
  m_Ea(Ea) {
  StatusCode scmgn = Gaudi::svcLocator()->service("MagneticFieldSvc",m_pmgnIMF); 
  if(scmgn!=StatusCode::SUCCESS) { 
    std::cout<< "Unable to open Magnetic field service"<<std::endl;
  }
  m_bField = -10000*(m_pmgnIMF->getReferField());//zhangr 2012-09-06 for MagnField
  //m_bField = 10000*(m_pmgnIMF->getReferField());
  m_alpha = 10000. / 2.99792458 / m_bField;
  // m_alpha = 10000. / 2.99792458 / m_bField;
  // m_alpha = 333.564095;
  updateCache();
}

◆ Helix() [3/5]

Helix::Helix	(	const HepPoint3D &	pivot,
		const HepVector &	a )

Constructor without error matrix.

Definition at line 88 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

  : //m_bField(-10.0),
  //m_alpha(-333.564095),
  m_pivot(pivot),
  m_a(a),
  m_matrixValid(false),
  m_Ea(HepSymMatrix(5,0)) {
  StatusCode scmgn = Gaudi::svcLocator()->service("MagneticFieldSvc",m_pmgnIMF); 
  if(scmgn!=StatusCode::SUCCESS) { 
    // log << MSG::ERROR << "Unable to open Magnetic field service"<<endreq; 
    std::cout<< "Unable to open Magnetic field service"<<std::endl;
  }
  m_bField = -10000*(m_pmgnIMF->getReferField());//zhangr 2012-09-06 for MagnField
  //m_bField = 10000*(m_pmgnIMF->getReferField());
  m_alpha = 10000. / 2.99792458 / m_bField;
    // m_alpha = 333.564095;
 //cout<<"MdcFastTrakAlg:: bField,alpha: "<<m_bField<<" , "<<m_alpha<<endl;
    updateCache();
}

◆ Helix() [4/5]

Helix::Helix	(	const HepPoint3D &	position,
		const Hep3Vector &	momentum,
		double	charge )

Constructor with position, momentum, and charge.

Definition at line 109 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

  : //m_bField(-10.0),
  //m_alpha(-333.564095),
  m_pivot(position),
  m_a(HepVector(5,0)),
  m_matrixValid(false),
  m_Ea(HepSymMatrix(5,0)) {
  StatusCode scmgn = Gaudi::svcLocator()->service("MagneticFieldSvc",m_pmgnIMF); 
  if(scmgn!=StatusCode::SUCCESS) { 
    // log << MSG::ERROR << "Unable to open Magnetic field service"<<endreq; 
    std::cout<< "Unable to open Magnetic field service"<<std::endl;
  }
  m_bField = -10000*(m_pmgnIMF->getReferField());//zhangr 2012-09-06 for MagnField
  //m_bField = 10000*(m_pmgnIMF->getReferField());
  m_alpha = 10000. / 2.99792458 / m_bField;
  
  m_a[0] = 0.;
    m_a[1] = fmod(atan2(- momentum.x(), momentum.y())
          + M_PI4, M_PI2);
    m_a[3] = 0.;
    double perp(momentum.perp());
    if (perp != 0.0) {
    m_a[2] = charge / perp;
    m_a[4] = momentum.z() / perp; 
    }
    else {
    m_a[2] = charge * (DBL_MAX);
    if (momentum.z() >= 0) {
        m_a[4] = (DBL_MAX);
    } else {
        m_a[4] = -(DBL_MAX);
    }
    }
    // m_alpha = 333.564095;
    updateCache();
}

◆ Helix() [5/5]

Helix::Helix ( const Helix & i )

Definition at line 427 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

{
    m_bField = i.m_bField;
    m_alpha = i.m_alpha;
    m_pivot = i.m_pivot;
    m_a = i.m_a;
    m_Ea = i.m_Ea;
    m_matrixValid = i.m_matrixValid;
 
    m_center = i.m_center;
    m_cp = i.m_cp;
    m_sp = i.m_sp;
    m_pt = i.m_pt;
    m_r  = i.m_r;
    m_ac[0] = i.m_ac[0];
    m_ac[1] = i.m_ac[1];
    m_ac[2] = i.m_ac[2];
    m_ac[3] = i.m_ac[3];
    m_ac[4] = i.m_ac[4];
}

◆ ~Helix()

Helix::~Helix ( )

virtual

Destructor.

Definition at line 148 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

148 {

149}

Referenced by ~Helix().

Member Function Documentation

◆ a() [1/2]

const HepVector & Helix::a ( const HepVector & newA )

inline

sets helix parameters.

Definition at line 284 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                            {
    m_a = i;
    updateCache();
    return m_a;
}

◆ a() [2/2]

const HepVector & Helix::a ( void ) const

inline

returns helix parameters.

Definition at line 272 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                   {
    return m_a;
}

Referenced by a(), a(), TTrack::approach2D(), TBuilder0::buildStereo(), TBuilder::buildStereo(), TBuilderCosmic::buildStereo(), TBuilderCurl::buildStereo(), TBuilder0::buildStereo0(), TBuilderCurl::buildStereoMC(), HoughTrack::calculateZ_S(), TTrack::dump(), Emc_helix::Emc_Get(), EsTimeAlg::execute(), TTrack::fit2D(), HoughTrack::fitCircle(), HoughTrack::fitHelix(), HoughTrack::fitHelix(), TTrack::HelCyl(), Helix(), HelixHasNan(), HoughTrack::HoughTrack(), HoughTrack::HoughTrack(), TRunge::pivot(), TTrack::pt(), TTrack::ptot(), TTrack::pz(), TofFz_helix::TofFz_Get(), TrackKinematics(), TTrack::TTrack(), HoughTrack::update(), and HoughTrack::updateHelix().

◆ alpha()

double Helix::alpha ( void ) const

inline

Definition at line 307 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                       {
 
  return m_alpha;
}

Referenced by alpha(), HoughTrack::fitCircle(), HoughTrack::fitHelix(), HoughTrack::fitHelix(), CgemHitOnTrack::getFitStuff(), and HoughHit::residual().

◆ bFieldZ() [1/2]

double Helix::bFieldZ ( double a )

inline

sets/returns z componet of the magnetic field.

Definition at line 298 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                       {
    m_bField = a;
    m_alpha = 10000. / 2.99792458 / m_bField;
    updateCache();
    return m_bField;
}

Referenced by bFieldZ(), and bFieldZ().

◆ bFieldZ() [2/2]

double Helix::bFieldZ ( void ) const

inline

Definition at line 315 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                         {
    return m_bField;
}

Referenced by HoughTrack::HoughTrack(), HoughTrack::HoughTrack(), HoughTrack::HoughTrack(), and HoughTrack::HoughTrack().

◆ center()

const HepPoint3D & Helix::center ( void ) const

inline

returns position of helix center(z = 0.);

Definition at line 212 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                        {
    return m_center;
}

Referenced by TTrack::approach(), TTrack::approach2D(), TBuilderCurl::buildStereoMC(), HoughTrack::calculateZ_S(), calVirtualCircle(), center(), TTrack::center(), dPhi(), HoughTrack::driftDistRes(), TTrack::dump(), Emc_helix::Emc_Get(), EsTimeAlg::execute(), TTrack::fit2D(), TTrack::HelCyl(), HoughTrack::HoughTrack(), HoughTrack::HoughTrack(), TTrack::impact(), TRunge::intersect_cylinder(), TRunge::intersect_yz_plane(), TRunge::intersect_zx_plane(), IntersectCylinder(), HoughTrack::judgeCharge(), HoughTrack::judgeCharge(), HoughTrack::judgeHalf(), TTrackManager::merge(), HoughHit::residual(), TRunge::SetFlightLength(), TTrack::stereoHitForCurl(), TTrack::szPosition(), TTrack::szPosition(), TofFz_helix::TofFz_Get(), and HoughHit::VHitPosition().

◆ cosPhi0()

double Helix::cosPhi0 ( void ) const

inline

Definition at line 327 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                         {
    return m_cp;
}

Referenced by cosPhi0().

◆ cosTheta()

double Helix::cosTheta ( void ) const

inline

Definition at line 130 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

130{ return m_a[4]/sqrt(1.+ m_a[4]*m_a[4]); }

◆ curv()

double Helix::curv ( void ) const

inline

Definition at line 266 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                      {
    return m_r;
}

Referenced by TBuilder0::buildStereo(), TBuilder0::buildStereo0(), TBuilderCurl::buildStereoMC(), curv(), TTrack::stereoHitForCurl(), TTrack::szPosition(), and TTrack::szPosition().

◆ del4MDelA()

HepMatrix Helix::del4MDelA	(	double	phi,
		double	mass ) const

Definition at line 642 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                                              {
    //
    //   Calculate Jacobian (@4m/@a)
    //   Vector a  is helix parameters and phi is internal parameter.
    //   Vector 4m is 4 momentum.
    //
 
    HepMatrix d4MDA(4,5,0);
 
    double phi0 = m_ac[1];
    double cpa  = m_ac[2];
    double tnl  = m_ac[4];
 
    double cosf0phi = cos(phi0+phi);
    double sinf0phi = sin(phi0+phi);
 
    double rho;
    if(cpa != 0.)rho = 1./cpa;
    else rho = (DBL_MAX);
 
    double charge = 1.;
    if(cpa < 0.)charge = -1.;
 
    double E = sqrt(rho*rho*(1.+tnl*tnl)+mass*mass);
 
    d4MDA[0][1] = -fabs(rho)*cosf0phi;
    d4MDA[0][2] = charge*rho*rho*sinf0phi;
 
    d4MDA[1][1] = -fabs(rho)*sinf0phi;
    d4MDA[1][2] = -charge*rho*rho*cosf0phi;
 
    d4MDA[2][2] = -charge*rho*rho*tnl;
    d4MDA[2][4] = fabs(rho);
 
    if (cpa != 0.0 && E != 0.0) {
      d4MDA[3][2] = (-1.-tnl*tnl)/(cpa*cpa*cpa*E);
      d4MDA[3][4] = tnl/(cpa*cpa*E);
    } else {
      d4MDA[3][2] = (DBL_MAX);
      d4MDA[3][4] = (DBL_MAX);
    }
    return d4MDA;
}

Referenced by del4MDelA(), and momentum().

◆ del4MXDelA()

HepMatrix Helix::del4MXDelA	(	double	phi,
		double	mass ) const

Definition at line 688 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                                               {
    //
    //   Calculate Jacobian (@4mx/@a)
    //   Vector a  is helix parameters and phi is internal parameter.
    //   Vector 4xm is 4 momentum and position.
    //
 
    HepMatrix d4MXDA(7,5,0);
 
    const double & dr      = m_ac[0];
    const double & phi0    = m_ac[1];
    const double & cpa     = m_ac[2];
    //const double & dz      = m_ac[3];
    const double & tnl     = m_ac[4];
 
    double cosf0phi = cos(phi0+phi);
    double sinf0phi = sin(phi0+phi);
 
    double rho;
    if(cpa != 0.)rho = 1./cpa;
    else rho = (DBL_MAX);
 
    double charge = 1.;
    if(cpa < 0.)charge = -1.;
 
    double E = sqrt(rho * rho * (1. + tnl * tnl) + mass * mass);
 
    d4MXDA[0][1] = - fabs(rho) * cosf0phi;
    d4MXDA[0][2] = charge * rho * rho * sinf0phi;
 
    d4MXDA[1][1] = - fabs(rho) * sinf0phi;
    d4MXDA[1][2] = - charge * rho * rho * cosf0phi;
 
    d4MXDA[2][2] = - charge * rho * rho * tnl;
    d4MXDA[2][4] = fabs(rho);
 
    if (cpa != 0.0 && E != 0.0) {
      d4MXDA[3][2] = (- 1. - tnl * tnl) / (cpa * cpa * cpa * E);
      d4MXDA[3][4] = tnl / (cpa * cpa * E);
    } else {
      d4MXDA[3][2] = (DBL_MAX);
      d4MXDA[3][4] = (DBL_MAX);
    }
    
    d4MXDA[4][0] = m_cp;
    d4MXDA[4][1] = - dr * m_sp + m_r * (- m_sp + sinf0phi);
    if (cpa != 0.0) {
      d4MXDA[4][2] = - (m_r / cpa) * (m_cp - cosf0phi);
    } else {
      d4MXDA[4][2] = (DBL_MAX);
    }
     
    d4MXDA[5][0] = m_sp;
    d4MXDA[5][1] = dr * m_cp + m_r * (m_cp - cosf0phi);
    if (cpa != 0.0) {
      d4MXDA[5][2] = - (m_r / cpa) * (m_sp - sinf0phi);
 
      d4MXDA[6][2] = (m_r / cpa) * tnl * phi;
    } else {
      d4MXDA[5][2] = (DBL_MAX);
 
      d4MXDA[6][2] = (DBL_MAX);
    }
 
    d4MXDA[6][3] = 1.;
    d4MXDA[6][4] = - m_r * phi;
 
    return d4MXDA;
}

Referenced by del4MXDelA(), and momentum().

◆ delApDelA()

HepMatrix Helix::delApDelA ( const HepVector & ap ) const

Definition at line 483 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                                           {
    //
    //   Calculate Jacobian (@ap/@a)
    //   Vector ap is new helix parameters and a is old helix parameters. 
    //
 
    HepMatrix dApDA(5,5,0);
 
    const double & dr    = m_ac[0];
    const double & phi0  = m_ac[1];
    const double & cpa   = m_ac[2];
    //const double & dz    = m_ac[3];
    const double & tnl   = m_ac[4];
 
    double drp   = ap[0];
    double phi0p = ap[1];
    //double cpap  = ap[2];
    //double dzp   = ap[3];
    //double tnlp  = ap[4];
 
    double rdr   = m_r + dr;
    double rdrpr;
    if ((m_r + drp) != 0.0) {
      rdrpr = 1. / (m_r + drp);
    } else {
      rdrpr = (DBL_MAX);
    }
    // double csfd  = cos(phi0)*cos(phi0p) + sin(phi0)*sin(phi0p); 
    // double snfd  = cos(phi0)*sin(phi0p) - sin(phi0)*cos(phi0p); 
    double csfd  = cos(phi0p - phi0);
    double snfd  = sin(phi0p - phi0);
    double phid  = fmod(phi0p - phi0 + M_PI8, M_PI2);
    if (phid > M_PI) phid = phid - M_PI2;
 
    dApDA[0][0]  =  csfd;
    dApDA[0][1]  =  rdr*snfd;
    if(cpa!=0.0) {
      dApDA[0][2]  =  (m_r/cpa)*( 1.0 - csfd );
    } else {
      dApDA[0][2]  = (DBL_MAX);
    }
 
    dApDA[1][0]  = - rdrpr*snfd;
    dApDA[1][1]  = rdr*rdrpr*csfd;
    if(cpa!=0.0) {
      dApDA[1][2]  = (m_r/cpa)*rdrpr*snfd;
    } else {
      dApDA[1][2]  = (DBL_MAX);
    }
    
    dApDA[2][2]  = 1.0;
 
    dApDA[3][0]  = m_r*rdrpr*tnl*snfd;
    dApDA[3][1]  = m_r*tnl*(1.0 - rdr*rdrpr*csfd);
    if(cpa!=0.0) {
      dApDA[3][2]  = (m_r/cpa)*tnl*(phid - m_r*rdrpr*snfd);
    } else {
      dApDA[3][2]  = (DBL_MAX);
    }
    dApDA[3][3]  = 1.0;
    dApDA[3][4]  = - m_r*phid;
 
    dApDA[4][4] = 1.0;
 
    return dApDA;
}

Referenced by delApDelA(), and pivot().

◆ delMDelA()

HepMatrix Helix::delMDelA ( double phi ) const

Definition at line 605 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                                {
    //
    //   Calculate Jacobian (@m/@a)
    //   Vector a is helix parameters and phi is internal parameter.
    //   Vector m is momentum.
    //
 
    HepMatrix dMDA(3,5,0);
 
    const double & phi0 = m_ac[1];
    const double & cpa  = m_ac[2];
    const double & tnl  = m_ac[4];
 
    double cosf0phi = cos(phi0+phi);
    double sinf0phi = sin(phi0+phi);
 
    double rho;
    if(cpa != 0.)rho = 1./cpa;
    else rho = (DBL_MAX);
 
    double charge = 1.;
    if(cpa < 0.)charge = -1.;
 
    dMDA[0][1] = -fabs(rho)*cosf0phi;
    dMDA[0][2] = charge*rho*rho*sinf0phi;
 
    dMDA[1][1] = -fabs(rho)*sinf0phi;
    dMDA[1][2] = -charge*rho*rho*cosf0phi;
 
    dMDA[2][2] = -charge*rho*rho*tnl;
    dMDA[2][4] = fabs(rho);
 
    return dMDA;
}

Referenced by delMDelA(), and momentum().

◆ delXDelA()

HepMatrix Helix::delXDelA ( double phi ) const

Definition at line 551 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                                {
    //
    //   Calculate Jacobian (@x/@a)
    //   Vector a is helix parameters and phi is internal parameter
    //   which specifys the point to be calculated for Ex(phi).
    //
 
    HepMatrix dXDA(3,5,0);
 
    const double & dr      = m_ac[0];
    const double & phi0    = m_ac[1];
    const double & cpa     = m_ac[2];
    //const double & dz      = m_ac[3];
    const double & tnl     = m_ac[4];
 
    double cosf0phi = cos(phi0 + phi);
    double sinf0phi = sin(phi0 + phi);
 
    dXDA[0][0]     = m_cp;
    dXDA[0][1]     = - dr * m_sp + m_r * (- m_sp + sinf0phi); 
    if(cpa!=0.0) {
      dXDA[0][2]     = - (m_r / cpa) * (m_cp - cosf0phi);
    } else {
      dXDA[0][2] = (DBL_MAX);
    }
    // dXDA[0][3]     = 0.0;
    // dXDA[0][4]     = 0.0;
 
    dXDA[1][0]     = m_sp;
    dXDA[1][1]     = dr * m_cp + m_r * (m_cp - cosf0phi);
    if(cpa!=0.0) {
      dXDA[1][2]     = - (m_r / cpa) * (m_sp - sinf0phi);
    } else {
      dXDA[1][2] = (DBL_MAX);
    }
    // dXDA[1][3]     = 0.0;
    // dXDA[1][4]     = 0.0;
 
    // dXDA[2][0]     = 0.0;
    // dXDA[2][1]     = 0.0;
    if(cpa!=0.0) {
      dXDA[2][2]     = (m_r / cpa) * tnl * phi;
    } else {
      dXDA[2][2] = (DBL_MAX);
    }
    dXDA[2][3]     = 1.0;
    dXDA[2][4]     = - m_r * phi;
 
    return dXDA;
}

Referenced by delXDelA(), CgemHitOnTrack::getFitStuff(), and x().

◆ direction()

Hep3Vector Helix::direction ( double dPhi = 0. ) const

inline

returns direction vector after rotating angle dPhi in phi direction.

Definition at line 230 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                                 {
    return momentum(phi).unit();
}

Referenced by direction(), Emc_helix::Emc_Get(), CgemHitOnTrack::getFitStuff(), CgemHitOnTrack::getFitStuff(), and TofFz_helix::TofFz_Get().

◆ dPhi()

double Helix::dPhi ( HepPoint3D & hit ) const

Definition at line 835 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

{
    double isClockWise = m_r/fabs(m_r);
    double x_cw = center().x()-hit.x();
    double y_cw = center().y()-hit.y();
    x_cw = isClockWise*x_cw;
    y_cw = isClockWise*y_cw;
    double phi_cw = atan2(y_cw,x_cw);
    double dphi = phi_cw-phi0();
    if(isClockWise>0) 
    {
        while(dphi>0)       dphi-=2*M_PI;
        while(dphi<-2*M_PI) dphi+=2*M_PI;
    }
    else {
        while(dphi<0)       dphi+=2*M_PI;
        while(dphi>2*M_PI)  dphi-=2*M_PI;
    }
    return dphi;
}

Referenced by dPhi(), flightArc(), and IntersectCylinder().

◆ dr()

double Helix::dr ( void ) const

inline

returns an element of parameters.

Definition at line 236 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                    {
    return m_ac[0];
}

Referenced by del4MXDelA(), delApDelA(), delXDelA(), dr(), CgemHitOnTrack::getFitStuff(), HoughTrack::HoughTrack(), HoughTrack::HoughTrack(), HoughTrack::HoughTrack(), pivot(), HoughTrack::print(), HoughHit::residual(), and HoughTrack::updateCirclePar().

◆ dz()

double Helix::dz ( void ) const

inline

Definition at line 254 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                    {
    return m_ac[3];
}

Referenced by dz(), CgemHitOnTrack::getFitStuff(), HoughTrack::HoughTrack(), HoughTrack::HoughTrack(), HoughTrack::HoughTrack(), TTrackManager::maskCurl(), TTrackManager::merge(), pivot(), HoughTrack::print(), HoughHit::residual(), HoughHit::residual(), HoughTrack::setDz(), TRunge::SetFlightLength(), and HoughHit::updateVHit().

◆ Ea() [1/2]

const HepSymMatrix & Helix::Ea ( const HepSymMatrix & newdA )

inline

sets helix paramters and error matrix.

Definition at line 292 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                                {
    return m_Ea = i;
}

◆ Ea() [2/2]

const HepSymMatrix & Helix::Ea ( void ) const

inline

returns error matrix.

Definition at line 278 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                    {
    return m_Ea;
}

Referenced by Ea(), Ea(), TTrack::fit2D(), HoughTrack::fitCircle(), HoughTrack::fitHelix(), Helix(), HelixHasNan(), HoughTrack::HoughTrack(), TRunge::pivot(), PositiveDefinite(), and HoughTrack::update().

◆ flightArc() [1/2]

double Helix::flightArc ( double r ) const

Definition at line 804 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

{
    double phi_turn = IntersectCylinder(r);
    double arcLength = m_r*phi_turn;
    arcLength = fabs(arcLength);
    return arcLength;
}

◆ flightArc() [2/2]

double Helix::flightArc ( HepPoint3D & hit ) const

Definition at line 780 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

{
    /*
    double rc = center().perp();
    //double l = center().perp(hit);
    double l = sqrt( (center().x()-hit.x()) * (center().x()-hit.x()) + (center().y()-hit.y()) * (center().y()-hit.y()) );
    double rHit = hit.perp();
    double cosPhi = (rc*rc + l * l  - rHit * rHit) / (2 * rc * l);
    //double cosPhi = (m_rad * m_rad + l * l  - r * r) / (2 * m_rad * l);
    if(cosPhi < -1 || cosPhi > 1) return 0;
    double dPhi = acos(cosPhi);// [0, pi)
    //double phiTrkFlt = IntersectCylinder(rHit);
    //double arcLength = rc*dPhi;
    double xHit = hit.getHitPoint().x();
    double yHit = hit.getHitPoint().y();
    double xCenter = center().x();
    double yCenter = center().y();
    double leftOrRight = xHit*yCenter - xCenter*yHit;
    */
    double dphi = dPhi(hit);
    double arcLength = fabs(m_r*dphi);
    return arcLength;
}

Referenced by HoughTrack::calculateZ_S(), HoughTrack::fitHelix(), HoughTrack::fitHelix(), flightArc(), flightArc(), flightLength(), HoughHit::residual(), and HoughHit::updateVHit().

◆ flightLength()

double Helix::flightLength ( HepPoint3D & hit ) const

Definition at line 812 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

{
    /*
    double rc = center().perp();
    //double l = center().perp(hit);
    double l = sqrt( (center().x()-hit.x()) * (center().x()-hit.x()) + (center().y()-hit.y()) * (center().y()-hit.y()) );
    double rHit = hit.perp();
    double cosPhi = (rc*rc + l * l  - rHit * rHit) / (2 * rc * l);
    //double cosPhi = (m_rad * m_rad + l * l  - r * r) / (2 * m_rad * l);
    if(cosPhi < -1 || cosPhi > 1) return 0;
    double dPhi = acos(cosPhi);
    //double dPhi = center().phi() - acos(cosPhi) - phi0();
    //double phiTrkFlt = IntersectCylinder(rHit);
    double arcLength = rc*dPhi;
    */
    
    double arcLength = flightArc(hit);
 
    double cosLambda = 1/sqrt(1+m_ac[4]*m_ac[4]);
    double flightLength = arcLength/cosLambda;
    return flightLength;
}

Referenced by HoughTrack::fitCircle(), flightLength(), and HoughHit::residual().

◆ ignoreErrorMatrix()

void Helix::ignoreErrorMatrix ( void )

unsets error matrix. Error calculations will be ignored after this function call until an error matrix be set again. 0 matrix will be return as a return value for error matrix when you call functions which returns an error matrix.

Definition at line 759 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                             {
    m_matrixValid = false;
    m_Ea *= 0.;
}

Referenced by EsTimeAlg::execute(), and ignoreErrorMatrix().

◆ IntersectCylinder()

double Helix::IntersectCylinder ( double r ) const

Definition at line 764 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

{
    double m_rad = radius();
    double l = center().perp();
 
    double cosPhi = (m_rad * m_rad + l * l  - r * r) / (2 * m_rad * l);
 
    if(cosPhi < -1 || cosPhi > 1) return 0;
 
    double dPhi = center().phi() - acos(cosPhi) - phi0();
 
    if(dPhi < -M_PI) dPhi += 2 * M_PI;
 
    return dPhi;
}

Referenced by HoughTrack::driftDistRes(), flightArc(), CgemHitOnTrack::getFitStuff(), CgemHitOnTrack::getFitStuff(), CgemHitOnTrack::getFitStuff(), CgemHitOnTrack::getFitStuff(), IntersectCylinder(), HoughHit::residual(), and HoughHit::residual().

◆ kappa()

double Helix::kappa ( void ) const

inline

Definition at line 248 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                       {
    return m_ac[2];
}

Referenced by TTrack::approach(), CgemHitOnTrack::getFitStuff(), HoughTrack::HoughTrack(), HoughTrack::HoughTrack(), HoughTrack::HoughTrack(), kappa(), pivot(), HoughTrack::print(), HoughHit::residual(), TRunge::SetFlightLength(), TTrack::TTrack(), TTrack::TTrack(), and HoughTrack::updateCirclePar().

◆ momentum() [1/5]

HepLorentzVector Helix::momentum	(	double	dPhi,
		double	mass ) const

returns 4momentum vector after rotating angle dPhi in phi direction.

Definition at line 250 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                                             {
    // 
    // Calculate momentum.
    //
    // Pt = | 1/kappa | (GeV/c)
    //
    // Px = -Pt * sin(phi0 + phi) 
    // Py =  Pt * cos(phi0 + phi)
    // Pz =  Pt * tan(lambda)
    //
    // E  = sqrt( 1/kappa/kappa * (1+tan(lambda)*tan(lambda)) + mass*mass )
 
    double pt = fabs(m_pt);
    double px = - pt * sin(m_ac[1] + phi);
    double py =   pt * cos(m_ac[1] + phi);
    double pz =   pt * m_ac[4];
    double E  =   sqrt(pt*pt*(1.+m_ac[4]*m_ac[4])+mass*mass);
 
    return HepLorentzVector(px, py, pz, E);
}

◆ momentum() [2/5]

HepLorentzVector Helix::momentum	(	double	dPhi,
		double	mass,
		HepPoint3D &	x,
		HepSymMatrix &	Emx ) const

returns 4momentum vector after rotating angle dPhi in phi direction.

Definition at line 298 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                                  {
  // 
  // Calculate momentum.
  //
  // Pt = | 1/kappa | (GeV/c)
  //
  // Px = -Pt * sin(phi0 + phi) 
  // Py =  Pt * cos(phi0 + phi)
  // Pz =  Pt * tan(lambda)
  //
  // E  = sqrt( 1/kappa/kappa * (1+tan(lambda)*tan(lambda)) + mass*mass )
  
  double pt = fabs(m_pt);
  double px = - pt * sin(m_ac[1] + phi);
  double py =   pt * cos(m_ac[1] + phi);
  double pz =   pt * m_ac[4];
  double E  = sqrt(pt * pt * (1. + m_ac[4] * m_ac[4]) + mass * mass);
 
  x.setX(m_pivot.x() + m_ac[0] * m_cp + m_r * (m_cp - cos(m_ac[1] + phi)));
  x.setY(m_pivot.y() + m_ac[0] * m_sp + m_r * (m_sp - sin(m_ac[1] + phi)));
  x.setZ(m_pivot.z() + m_ac[3] - m_r * m_ac[4] * phi);
 
  if (m_matrixValid) Emx = m_Ea.similarity(del4MXDelA(phi,mass));
  else               Emx = m_Ea;
  
  return HepLorentzVector(px, py, pz, E);
}

◆ momentum() [3/5]

HepLorentzVector Helix::momentum	(	double	dPhi,
		double	mass,
		HepSymMatrix &	Em ) const

returns 4momentum vector after rotating angle dPhi in phi direction.

Definition at line 273 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                                                                {
    // 
    // Calculate momentum.
    //
    // Pt = | 1/kappa | (GeV/c)
    //
    // Px = -Pt * sin(phi0 + phi) 
    // Py =  Pt * cos(phi0 + phi)
    // Pz =  Pt * tan(lambda)
    //
    // E  = sqrt( 1/kappa/kappa * (1+tan(lambda)*tan(lambda)) + mass*mass )
 
    double pt = fabs(m_pt);
    double px = - pt * sin(m_ac[1] + phi);
    double py =   pt * cos(m_ac[1] + phi);
    double pz =   pt * m_ac[4];
    double E  =   sqrt(pt*pt*(1.+m_ac[4]*m_ac[4])+mass*mass);
 
    if (m_matrixValid) Em = m_Ea.similarity(del4MDelA(phi,mass));
    else               Em = m_Ea;
 
    return HepLorentzVector(px, py, pz, E);
}

◆ momentum() [4/5]

Hep3Vector Helix::momentum	(	double	dPhi,
		HepSymMatrix &	Em ) const

returns momentum vector after rotating angle dPhi in phi direction.

Definition at line 227 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                                                   {
    // 
    // Calculate momentum.
    //
    // Pt = | 1/kappa | (GeV/c)
    //
    // Px = -Pt * sin(phi0 + phi) 
    // Py =  Pt * cos(phi0 + phi)
    // Pz =  Pt * tan(lambda)
    //
 
    double pt = fabs(m_pt);
    double px = - pt * sin(m_ac[1] + phi);
    double py =   pt * cos(m_ac[1] + phi);
    double pz =   pt * m_ac[4];
 
    if (m_matrixValid) Em = m_Ea.similarity(delMDelA(phi));
    else               Em = m_Ea;
 
    return Hep3Vector(px, py, pz);
}

◆ momentum() [5/5]

Hep3Vector Helix::momentum ( double dPhi = 0. ) const

returns momentum vector after rotating angle dPhi in phi direction.

Definition at line 207 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                                {
    // 
    // Calculate momentum.
    //
    // Pt = | 1/kappa | (GeV/c)
    //
    // Px = -Pt * sin(phi0 + phi) 
    // Py =  Pt * cos(phi0 + phi)
    // Pz =  Pt * tan(lambda)
    //
 
    double pt = fabs(m_pt);
    double px = - pt * sin(m_ac[1] + phi);
    double py =   pt * cos(m_ac[1] + phi);
    double pz =   pt * m_ac[4];
 
    return Hep3Vector(px, py, pz);
}

Referenced by EsTimeAlg::execute(), momentum(), momentum(), momentum(), momentum(), momentum(), and TTrack::p().

◆ operator=()

Helix & Helix::operator= ( const Helix & i )

Copy operator.

Definition at line 403 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                                  {
    if (this == & i) return * this;
 
    m_bField = i.m_bField;
    m_alpha = i.m_alpha;
    m_pivot = i.m_pivot;
    m_a = i.m_a;
    m_Ea = i.m_Ea;
    m_matrixValid = i.m_matrixValid;
 
    m_center = i.m_center;
    m_cp = i.m_cp;
    m_sp = i.m_sp;
    m_pt = i.m_pt;
    m_r  = i.m_r;
    m_ac[0] = i.m_ac[0];
    m_ac[1] = i.m_ac[1];
    m_ac[2] = i.m_ac[2];
    m_ac[3] = i.m_ac[3];
    m_ac[4] = i.m_ac[4];
 
    return * this;
}

Referenced by HoughTrack::operator=().

◆ phi0()

double Helix::phi0 ( void ) const

inline

Definition at line 242 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                      {
    return m_ac[1];
}

Referenced by TTrack::approach(), del4MDelA(), del4MXDelA(), delApDelA(), delMDelA(), delXDelA(), dPhi(), HoughTrack::fitCircle(), HoughTrack::fitHelix(), HoughTrack::fitHelix(), CgemHitOnTrack::getFitStuff(), HoughTrack::HoughTrack(), HoughTrack::HoughTrack(), HoughTrack::HoughTrack(), TRunge::intersect_cylinder(), IntersectCylinder(), phi0(), pivot(), HoughTrack::print(), HoughHit::residual(), and HoughTrack::updateCirclePar().

◆ pivot() [1/2]

const HepPoint3D & Helix::pivot ( const HepPoint3D & newPivot )

sets pivot position.

Definition at line 331 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                                        {
    const double & dr    = m_ac[0];
    const double & phi0  = m_ac[1];
    const double & kappa = m_ac[2];
    const double & dz    = m_ac[3];
    const double & tanl  = m_ac[4];
 
    double rdr = dr + m_r;
    double phi = fmod(phi0 + M_PI4, M_PI2);
    double csf0 = cos(phi);
    double snf0 = (1. - csf0) * (1. + csf0);
    snf0 = sqrt((snf0 > 0.) ? snf0 : 0.);
    if(phi > M_PI) snf0 = - snf0;
 
    double xc = m_pivot.x() + rdr * csf0;
    double yc = m_pivot.y() + rdr * snf0;
    double csf, snf;
    if(m_r != 0.0) {
      csf = (xc - newPivot.x()) / m_r;
      snf = (yc - newPivot.y()) / m_r;
      double anrm = sqrt(csf * csf + snf * snf);
      if(anrm != 0.0) {
    csf /= anrm;
    snf /= anrm;
    phi = atan2(snf, csf);
      } else {
    csf = 1.0;
    snf = 0.0;
    phi = 0.0;
      }
    } else {
      csf = 1.0;
      snf = 0.0;
      phi = 0.0;
    }
    double phid = fmod(phi - phi0 + M_PI8, M_PI2);
    if(phid > M_PI) phid = phid - M_PI2;
    double drp = (m_pivot.x() + dr * csf0 + m_r * (csf0 - csf) - newPivot.x())
    * csf
    + (m_pivot.y() + dr * snf0 + m_r * (snf0 - snf) - newPivot.y()) * snf;
    double dzp = m_pivot.z() + dz - m_r * tanl * phid - newPivot.z();
 
    HepVector ap(5);
    ap[0] = drp;
    ap[1] = fmod(phi + M_PI4, M_PI2);
    ap[2] = kappa;
    ap[3] = dzp;
    ap[4] = tanl;
 
    //    if (m_matrixValid) m_Ea.assign(delApDelA(ap) * m_Ea * delApDelA(ap).T());
    if (m_matrixValid) m_Ea = m_Ea.similarity(delApDelA(ap));
 
    m_a = ap;
    m_pivot = newPivot;
 
    //...Are these needed?...iw...
    updateCache();
    return m_pivot;
}

◆ pivot() [2/2]

const HepPoint3D & Helix::pivot ( void ) const

inline

returns pivot position.

Definition at line 218 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                       {
    return m_pivot;
}

Referenced by TPerfectFinder::doit(), TTrack::dump(), Emc_helix::Emc_Get(), EsTimeAlg::execute(), HoughTrack::fitCircle(), HoughTrack::fitHelix(), HoughFinder::getMcParticleCol(), TTrack::HelCyl(), Helix(), HoughTrack::HoughTrack(), HoughTrack::HoughTrack(), TTrackManager::maskCurl(), TTrackManager::merge(), TTrack::movePivot(), pivot(), pivot(), TRunge::pivot(), HoughHit::residual(), TRunge::SetFlightLength(), TofFz_helix::TofFz_Get(), TrackKinematics(), HoughTrack::update(), and HoughTrack::updateHelix().

◆ pt()

double Helix::pt ( void ) const

inline

Definition at line 129 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

129{ return m_pt; }

Referenced by HoughTrack::findVHot(), largerPt(), momentum(), momentum(), momentum(), momentum(), momentum(), and HoughTrack::print().

◆ radius()

double Helix::radius ( void ) const

inline

returns radious of helix.

Definition at line 224 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                        {
    return m_r;
}

Referenced by HoughTrack::calculateZ_S(), HoughTrack::driftDistRes(), Emc_helix::Emc_Get(), EsTimeAlg::execute(), TTrack::fit2D(), TTrack::HelCyl(), HoughTrack::HoughTrack(), HoughTrack::HoughTrack(), TTrack::impact(), RkFitCylinder::intersect(), RkFitCylinder::intersect(), TRunge::intersect_cylinder(), TRunge::intersect_xy_plane(), TRunge::intersect_yz_plane(), TRunge::intersect_zx_plane(), IntersectCylinder(), TTrackManager::merge(), radius(), TTrack::radius(), HoughHit::residual(), TofFz_helix::TofFz_Get(), and HoughHit::VHitPosition().

◆ set()

void Helix::set	(	const HepPoint3D &	pivot,
		const HepVector &	a,
		const HepSymMatrix &	Ea )

sets helix pivot position, parameters, and error matrix.

Definition at line 392 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                                {
    m_pivot = pivot;
    m_a = a;
    m_Ea = Ea;
    m_matrixValid = true;
    updateCache();
}

Referenced by HoughTrack::HoughTrack(), set(), and HoughTrack::update().

◆ sinPhi0()

double Helix::sinPhi0 ( void ) const

inline

Definition at line 321 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                         {
    return m_sp;
}

Referenced by sinPhi0().

◆ tanl()

double Helix::tanl ( void ) const

inline

Definition at line 260 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

                      {
    return m_ac[4];
}

Referenced by TTrack::approach(), HoughTrack::fitCircle(), HoughTrack::fitHelix(), HoughTrack::fitHelix(), CgemHitOnTrack::getFitStuff(), HoughTrack::HoughTrack(), HoughTrack::HoughTrack(), HoughTrack::HoughTrack(), RkFitCylinder::intersect(), RkFitCylinder::intersect(), TRunge::intersect_xy_plane(), pivot(), HoughTrack::print(), HoughHit::residual(), HoughHit::residual(), TRunge::SetFlightLength(), HoughTrack::setTanl(), tanl(), and HoughHit::updateVHit().

◆ x() [1/3]

double * Helix::x	(	double	dPhi,
		double	p[3] ) const

Definition at line 169 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                                      {
    //
    // Calculate position (x,y,z) along helix.
    //   
    // x = x0 + dr * cos(phi0) + (alpha / kappa) * (cos(phi0) - cos(phi0+phi))
    // y = y0 + dr * sin(phi0) + (alpha / kappa) * (sin(phi0) - sin(phi0+phi))
    // z = z0 + dz             - (alpha / kappa) * tan(lambda) * phi
    //
 
    p[0] = m_pivot.x() + m_ac[0] * m_cp + m_r * (m_cp - cos(m_ac[1] + phi));
    p[1] = m_pivot.y() + m_ac[0] * m_sp + m_r * (m_sp - sin(m_ac[1] + phi));
    p[2] = m_pivot.z() + m_ac[3] - m_r * m_ac[4] * phi;
 
    return p;
}

◆ x() [2/3]

HepPoint3D Helix::x	(	double	dPhi,
		HepSymMatrix &	Ex ) const

returns position and convariance matrix(Ex) after rotation.

Definition at line 186 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                                            {
    double x = m_pivot.x() + m_ac[0] * m_cp + m_r * (m_cp - cos(m_ac[1] +phi));
    double y = m_pivot.y() + m_ac[0] * m_sp + m_r * (m_sp - sin(m_ac[1] +phi));
    double z = m_pivot.z() + m_ac[3] - m_r * m_ac[4] * phi;
 
    //
    //   Calculate position error matrix.
    //   Ex(phi) = (@x/@a)(Ea)(@x/@a)^T, phi is deflection angle to specify the
    //   point to be calcualted.
    //
    // HepMatrix dXDA(3, 5, 0);
    // dXDA = delXDelA(phi);
    // Ex.assign(dXDA * m_Ea * dXDA.T());
 
    if (m_matrixValid) Ex = m_Ea.similarity(delXDelA(phi));
    else               Ex = m_Ea;
 
    return HepPoint3D(x, y, z);
}

◆ x() [3/3]

HepPoint3D Helix::x ( double dPhi = 0. ) const

returns position after rotating angle dPhi in phi direction.

Definition at line 152 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/src/Helix.cxx.

                         {
    //
    // Calculate position (x,y,z) along helix.
    //   
    // x = x0 + dr * cos(phi0) + (alpha / kappa) * (cos(phi0) - cos(phi0+phi))
    // y = y0 + dr * sin(phi0) + (alpha / kappa) * (sin(phi0) - sin(phi0+phi))
    // z = z0 + dz             - (alpha / kappa) * tan(lambda) * phi
    //
 
    double x = m_pivot.x() + m_ac[0] * m_cp + m_r * (m_cp - cos(m_ac[1] +phi));
    double y = m_pivot.y() + m_ac[0] * m_sp + m_r * (m_sp - sin(m_ac[1] +phi));
    double z = m_pivot.z() + m_ac[3] - m_r * m_ac[4] * phi;
 
    return HepPoint3D(x, y, z);
}

Referenced by TTrack::approach(), TTrack::approach2D(), HoughTrack::driftDistRes(), EsTimeAlg::execute(), TTrack::fit2D(), CgemHitOnTrack::getFitStuff(), CgemHitOnTrack::getFitStuff(), CgemHitOnTrack::getFitStuff(), CgemHitOnTrack::getFitStuff(), TTrack::HelCyl(), RkFitCylinder::intersect(), RkFitCylinder::intersect(), HoughHit::residual(), HoughHit::residual(), TRunge::SetFlightLength(), TofFz_helix::TofFz_Get(), x(), x(), and x().

Member Data Documentation

◆ ConstantAlpha

const double Helix::ConstantAlpha = 333.564095

static

Constant alpha for uniform field.

Definition at line 180 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

◆ m_alpha

double Helix::m_alpha

protected

Definition at line 173 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

Referenced by alpha(), bFieldZ(), HoughTrack::fitCircle(), Helix(), Helix(), Helix(), Helix(), Helix(), HoughTrack::HoughTrack(), operator=(), and HoughTrack::update().

◆ m_bField

double Helix::m_bField

protected

Definition at line 172 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

Referenced by bFieldZ(), bFieldZ(), Helix(), Helix(), Helix(), Helix(), Helix(), and operator=().

◆ m_pmgnIMF

IMagneticFieldSvc* Helix::m_pmgnIMF

protected

Definition at line 171 of file Reconstruction/TrackUtil/TrackUtil-00-00-12/TrackUtil/Helix.h.

Referenced by Helix(), Helix(), Helix(), and Helix().

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

Public Member Functions

Static Public Attributes

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ Helix() [1/5]

◆ Helix() [2/5]

◆ Helix() [3/5]

◆ Helix() [4/5]

◆ Helix() [5/5]

◆ ~Helix()

Member Function Documentation

◆ a() [1/2]

◆ a() [2/2]

◆ alpha()

◆ bFieldZ() [1/2]

◆ bFieldZ() [2/2]

◆ center()

◆ cosPhi0()

◆ cosTheta()

◆ curv()

◆ del4MDelA()

◆ del4MXDelA()

◆ delApDelA()

◆ delMDelA()

◆ delXDelA()

◆ direction()

◆ dPhi()

◆ dr()

◆ dz()

◆ Ea() [1/2]

◆ Ea() [2/2]

◆ flightArc() [1/2]

◆ flightArc() [2/2]

◆ flightLength()

◆ ignoreErrorMatrix()

◆ IntersectCylinder()

◆ kappa()

◆ momentum() [1/5]

◆ momentum() [2/5]

◆ momentum() [3/5]

◆ momentum() [4/5]

◆ momentum() [5/5]

◆ operator=()

◆ phi0()

◆ pivot() [1/2]

◆ pivot() [2/2]

◆ pt()

◆ radius()

◆ set()

◆ sinPhi0()

◆ tanl()

◆ x() [1/3]

◆ x() [2/3]

◆ x() [3/3]

Member Data Documentation

◆ ConstantAlpha

◆ m_alpha

◆ m_bField

◆ m_pmgnIMF