Helix Class Reference

Helix parameter class. More...

#include <Helix.h>

List of all members.

Public Member Functions
	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.
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
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
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
Private Member Functions
void	updateCache (void)
Private Attributes
HepPoint3D	m_pivot
HepVector	m_a
HepSymMatrix	m_Ea
bool	m_matrixValid
HepPoint3D	m_center
double	m_cp
double	m_sp
double	m_pt
double	m_r
double	m_ac [5]

---

Detailed Description

Helix parameter class.

Definition at line 53 of file Helix.h.

---

Constructor & Destructor Documentation

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

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

Definition at line 47 of file Helix.cxx.

References IMagneticFieldSvc::getReferField(), m_alpha, m_bField, m_pmgnIMF, and updateCache().

  : //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());
  m_alpha = 10000. / 2.99792458 / m_bField;
  // m_alpha = 10000. / 2.99792458 / m_bField;
  // m_alpha = 333.564095;
  updateCache();
}

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

Constructor without error matrix.

Definition at line 67 of file Helix.cxx.

References IMagneticFieldSvc::getReferField(), m_alpha, m_bField, m_pmgnIMF, and updateCache().

  : //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());
  m_alpha = 10000. / 2.99792458 / m_bField;
    // m_alpha = 333.564095;
 //cout<<"MdcFastTrakAlg:: bField,alpha: "<<m_bField<<" , "<<m_alpha<<endl;
    updateCache();
}

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

Constructor with position, momentum, and charge.

Definition at line 87 of file Helix.cxx.

References DBL_MAX, IMagneticFieldSvc::getReferField(), m_a, m_alpha, m_bField, M_PI2, M_PI4, m_pmgnIMF, and updateCache().

  : //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());
  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::~Helix

(

)

[virtual]

Destructor.

Definition at line 125 of file Helix.cxx.

              {
}

---

Member Function Documentation

const HepVector & Helix::a

(

const HepVector &

newA

)

[inline]

sets helix parameters.

Definition at line 275 of file Helix.h.

References m_a, and updateCache().

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

const HepVector & Helix::a

(

void

)

const [inline]

returns helix parameters.

Definition at line 263 of file Helix.h.

References m_a.

Referenced by TTrack::approach2D(), TBuilderCurl::buildStereo(), TBuilderCosmic::buildStereo(), TBuilder0::buildStereo(), TBuilder::buildStereo(), TBuilder0::buildStereo0(), TBuilderCurl::buildStereoMC(), TCurlFinder::distance(), TTrack::dump(), TTrack::dxda(), TTrack::dxda2D(), Emc_helix::Emc_Get(), EsTimeAlg::execute(), TTrack::fit2D(), MdcHoughFinder::GetMcInfo(), HoughValidUpdate::GetMcInfo(), TTrack::HelCyl(), HelixHasNan(), FTFinder::makeTds(), TRunge::pivot(), TTrack::pt(), TTrack::ptot(), TTrack::pz(), TofFz_helix::TofFz_Get(), TrackKinematics(), and TTrack::TTrack().

                   {
    return m_a;
}

double Helix::bFieldZ

(

void

)

const [inline]

Definition at line 298 of file Helix.h.

References m_bField.

                         {
    return m_bField;
}

double Helix::bFieldZ

(

double

)

[inline]

sets/returns z componet of the magnetic field.

Definition at line 289 of file Helix.h.

References m_alpha, m_bField, and updateCache().

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

const HepPoint3D & Helix::center

(

void

)

const [inline]

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

Definition at line 203 of file Helix.h.

References m_center.

Referenced by TTrack::approach(), TTrack::approach2D(), TBuilderCurl::buildStereoMC(), calVirtualCircle(), TTrack::center(), TCurlFinder::distance(), TTrack::dump(), TTrack::dxda2D(), Emc_helix::Emc_Get(), EsTimeAlg::execute(), TConformalFinder0::findCloseClusters(), TFastFinder::findCloseHits(), TCurlFinder::findCloseHits(), TConformalFinder0::findCloseHits(), TTrack::fit2D(), TTrack::HelCyl(), TTrack::impact(), TRunge::intersect_cylinder(), TRunge::intersect_yz_plane(), TRunge::intersect_zx_plane(), TCurlFinder::mask3DTrack(), TTrackManager::merge(), TCurlFinder::merge3DTrack(), TCurlFinder::plotTrack(), TCurlFinder::salvage3DTrack(), TTrack::stereoHitForCurl(), TTrack::szPosition(), TofFz_helix::TofFz_Get(), and TCurlFinder::trace3DTrack().

                        {
    return m_center;
}

double Helix::cosPhi0

(

void

)

const [inline]

Definition at line 310 of file Helix.h.

References m_cp.

                         {
    return m_cp;
}

double Helix::cosTheta

(

void

)

const [inline]

Definition at line 126 of file Helix.h.

References m_a.

Referenced by MdcHoughFinder::GetMcInfo(), and HoughValidUpdate::GetMcInfo().

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

double Helix::curv

(

void

)

const [inline]

Definition at line 257 of file Helix.h.

References m_r.

Referenced by TBuilder0::buildStereo(), TBuilder0::buildStereo0(), TBuilderCurl::buildStereoMC(), TFastFinder::findCloseHits(), TCurlFinder::findCloseHits(), TConformalFinder0::findCloseHits(), TTrack::stereoHitForCurl(), and TTrack::szPosition().

                      {
    return m_r;
}

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

Definition at line 597 of file Helix.cxx.

References cos(), DBL_MAX, m_ac, phi0(), and sin().

Referenced by momentum(), and KalmanFit::Helix::momentum().

                                              {
    //
    //   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;
}

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

Definition at line 643 of file Helix.cxx.

References cos(), DBL_MAX, dr(), dz(), m_ac, m_cp, m_r, m_sp, phi0(), and sin().

Referenced by momentum(), and KalmanFit::Helix::momentum().

                                               {
    //
    //   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;
}

HepMatrix Helix::delApDelA

(

const HepVector &

ap

)

const

Definition at line 438 of file Helix.cxx.

References cos(), DBL_MAX, dr(), dz(), m_ac, M_PI, M_PI2, M_PI8, m_r, phi0(), and sin().

Referenced by pivot(), and KalmanFit::Helix::pivot().

                                           {
    //
    //   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;
}

HepMatrix Helix::delMDelA

(

double

phi

)

const

Definition at line 560 of file Helix.cxx.

References cos(), DBL_MAX, m_ac, phi0(), and sin().

Referenced by momentum(), and KalmanFit::Helix::momentum().

                                {
    //
    //   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;
}

HepMatrix Helix::delXDelA

(

double

phi

)

const

Definition at line 506 of file Helix.cxx.

References cos(), DBL_MAX, dr(), dz(), m_ac, m_cp, m_r, m_sp, phi0(), and sin().

Referenced by x(), and KalmanFit::Helix::x().

                                {
    //
    //   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;
}

Hep3Vector Helix::direction

(

double

dPhi = 0.

)

const [inline]

returns direction vector after rotating angle dPhi in phi direction.

Definition at line 221 of file Helix.h.

References momentum().

Referenced by Emc_helix::Emc_Get(), THelixFitter::main(), and TofFz_helix::TofFz_Get().

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

double Helix::dr

(

void

)

const [inline]

returns an element of parameters.

Definition at line 227 of file Helix.h.

References m_ac.

Referenced by del4MXDelA(), KalmanFit::Helix::del4MXDelA(), delApDelA(), KalmanFit::Helix::delApDelA(), delXDelA(), KalmanFit::Helix::delXDelA(), MdcHoughFinder::GetMcInfo(), HoughValidUpdate::GetMcInfo(), FTFinder::makeMdst(), pivot(), and KalmanFit::Helix::pivot().

                    {
    return m_ac[0];
}

double Helix::dz

(

void

)

const [inline]

Definition at line 245 of file Helix.h.

References m_ac.

Referenced by del4MXDelA(), KalmanFit::Helix::del4MXDelA(), delApDelA(), KalmanFit::Helix::delApDelA(), delXDelA(), KalmanFit::Helix::delXDelA(), MdcHoughFinder::GetMcInfo(), HoughValidUpdate::GetMcInfo(), TCurlFinder::makeCurlTracks(), FTFinder::makeMdst(), TTrackManager::maskCurl(), TTrackManager::merge(), TCurlFinder::merge3DTrack(), pivot(), KalmanFit::Helix::pivot(), and TRunge::SetFlightLength().

                    {
    return m_ac[3];
}

const HepSymMatrix & Helix::Ea

(

const HepSymMatrix &

newdA

)

[inline]

sets helix paramters and error matrix.

Definition at line 283 of file Helix.h.

References m_Ea.

                                {
    return m_Ea = i;
}

const HepSymMatrix & Helix::Ea

(

void

)

const [inline]

returns error matrix.

Definition at line 269 of file Helix.h.

References m_Ea.

Referenced by TTrackMC::compare(), TTrack::fit2D(), HelixHasNan(), FTFinder::makeTds(), TRunge::pivot(), and PositiveDefinite().

                    {
    return m_Ea;
}

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 714 of file Helix.cxx.

References m_Ea, and m_matrixValid.

Referenced by EsTimeAlg::execute().

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

double Helix::kappa

(

void

)

const [inline]

Definition at line 239 of file Helix.h.

References m_ac.

Referenced by TTrack::approach(), TTrackMC::compare(), FTFinder::makeMdst(), pivot(), KalmanFit::Helix::pivot(), and TTrack::TTrack().

                       {
    return m_ac[2];
}

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 275 of file Helix.cxx.

References cos(), del4MXDelA(), m_ac, m_cp, m_Ea, m_matrixValid, m_pivot, m_pt, m_r, m_sp, pt(), and sin().

                                          {
  // 
  // 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);
}

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

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

Definition at line 250 of file Helix.cxx.

References cos(), del4MDelA(), m_ac, m_Ea, m_matrixValid, m_pt, pt(), and sin().

                                                                {
    // 
    // 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);
}

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

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

Definition at line 227 of file Helix.cxx.

References cos(), m_ac, m_pt, pt(), and sin().

                                             {
    // 
    // 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);
}

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

returns momentum vector after rotating angle dPhi in phi direction.

Definition at line 204 of file Helix.cxx.

References cos(), delMDelA(), m_ac, m_Ea, m_matrixValid, m_pt, pt(), and sin().

                                                   {
    // 
    // 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);
}

Hep3Vector Helix::momentum

(

double

dPhi = 0.

)

const

returns momentum vector after rotating angle dPhi in phi direction.

Definition at line 184 of file Helix.cxx.

References cos(), m_ac, m_pt, pt(), and sin().

Referenced by TTrackMC::compare(), direction(), KalmanFit::Helix::direction(), EsTimeAlg::execute(), MdcHoughFinder::GetMcInfo(), HoughValidUpdate::GetMcInfo(), FTFinder::makeMdst(), and TTrack::p().

                                {
    // 
    // 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);
}

Helix & Helix::operator=

(

const Helix &

)

Copy operator.

Definition at line 380 of file Helix.cxx.

References genRecEmupikp::i, m_a, m_ac, m_alpha, m_bField, m_center, m_cp, m_Ea, m_matrixValid, m_pivot, m_pt, m_r, and m_sp.

                                  {
    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;
}

double Helix::phi0

(

void

)

const [inline]

Definition at line 233 of file Helix.h.

References m_ac.

Referenced by TTrack::approach(), del4MDelA(), KalmanFit::Helix::del4MDelA(), del4MXDelA(), KalmanFit::Helix::del4MXDelA(), delApDelA(), KalmanFit::Helix::delApDelA(), delMDelA(), KalmanFit::Helix::delMDelA(), delXDelA(), KalmanFit::Helix::delXDelA(), MdcHoughFinder::GetMcInfo(), HoughValidUpdate::GetMcInfo(), TRunge::intersect_cylinder(), FTFinder::makeMdst(), pivot(), and KalmanFit::Helix::pivot().

                      {
    return m_ac[1];
}

const HepPoint3D & Helix::pivot

(

const HepPoint3D &

newPivot

)

sets pivot position.

Definition at line 308 of file Helix.cxx.

References cos(), delApDelA(), dr(), dz(), kappa(), m_a, m_ac, m_Ea, m_matrixValid, M_PI, M_PI2, M_PI4, M_PI8, m_pivot, m_r, phi0(), tanl(), and updateCache().

                                        {
    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;
}

const HepPoint3D & Helix::pivot

(

void

)

const [inline]

returns pivot position.

Definition at line 209 of file Helix.h.

References m_pivot.

Referenced by TTrackMC::compare(), TPerfectFinder::doit(), TTrack::dump(), Emc_helix::Emc_Get(), EsTimeAlg::execute(), MdcHoughFinder::GetMcInfo(), HoughValidUpdate::GetMcInfo(), TTrack::HelCyl(), FTFinder::makeTds(), TTrackManager::maskCurl(), TTrackManager::merge(), TTrack::movePivot(), TRunge::pivot(), TRunge::SetFlightLength(), TofFz_helix::TofFz_Get(), and TrackKinematics().

                       {
    return m_pivot;
}

double Helix::pt

(

void

)

const [inline]

Definition at line 125 of file Helix.h.

References m_pt.

Referenced by MdcHoughFinder::GetMcInfo(), HoughValidUpdate::GetMcInfo(), momentum(), and KalmanFit::Helix::momentum().

{ return m_pt; }

double Helix::radius

(

void

)

const [inline]

returns radious of helix.

Definition at line 215 of file Helix.h.

References m_r.

Referenced by TCurlFinder::distance(), Emc_helix::Emc_Get(), EsTimeAlg::execute(), TConformalFinder0::findCloseClusters(), TTrack::fit2D(), HoughValidUpdate::GetMcInfo(), TTrack::HelCyl(), TTrack::impact(), RkFitCylinder::intersect(), TRunge::intersect_cylinder(), TRunge::intersect_xy_plane(), TRunge::intersect_yz_plane(), TRunge::intersect_zx_plane(), TCurlFinder::mask3DTrack(), TTrackManager::merge(), TCurlFinder::merge3DTrack(), TCurlFinder::plotTrack(), TTrack::radius(), TofFz_helix::TofFz_Get(), and TCurlFinder::trace3DTrack().

                        {
    return m_r;
}

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

sets helix pivot position, parameters, and error matrix.

Definition at line 369 of file Helix.cxx.

References m_a, m_Ea, m_matrixValid, m_pivot, and updateCache().

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

double Helix::sinPhi0

(

void

)

const [inline]

Definition at line 304 of file Helix.h.

References m_sp.

                         {
    return m_sp;
}

double Helix::tanl

(

void

)

const [inline]

Definition at line 251 of file Helix.h.

References m_ac.

Referenced by TTrack::approach(), TTrackMC::compare(), MdcHoughFinder::GetMcInfo(), HoughValidUpdate::GetMcInfo(), RkFitCylinder::intersect(), TRunge::intersect_xy_plane(), FTFinder::makeMdst(), FTFinder::makeTds(), pivot(), and KalmanFit::Helix::pivot().

                      {
    return m_ac[4];
}

void Helix::updateCache

(

void

)

[private]

Definition at line 405 of file Helix.cxx.

References cos(), DBL_MAX, m_a, m_ac, m_alpha, m_center, m_cp, m_pivot, m_pt, m_r, m_sp, sin(), and x().

Referenced by a(), KalmanFit::Helix::a(), bFieldZ(), KalmanFit::Helix::bFieldZ(), Helix(), pivot(), KalmanFit::Helix::pivot(), set(), and KalmanFit::Helix::set().

                       {
    //
    //   Calculate Helix center( xc, yc ).
    //   
    //   xc = x0 + (dr + (alpha / kappa)) * cos(phi0)  (cm)
    //   yc = y0 + (dr + (alpha / kappa)) * sin(phi0)  (cm)
    //

    m_ac[0] = m_a[0];
    m_ac[1] = m_a[1];
    m_ac[2] = m_a[2];
    m_ac[3] = m_a[3];
    m_ac[4] = m_a[4];

    m_cp = cos(m_ac[1]);
    m_sp = sin(m_ac[1]);
    if (m_ac[2] != 0.0) {
        m_pt = 1. / m_ac[2];
        m_r = m_alpha / m_ac[2];
    }
    else {
        m_pt = (DBL_MAX);
        m_r = (DBL_MAX);
    }

    double x = m_pivot.x() + (m_ac[0] + m_r) * m_cp;
    double y = m_pivot.y() + (m_ac[0] + m_r) * m_sp;
    m_center.setX(x);
    m_center.setY(y);
    m_center.setZ(0.);
}

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

returns position and convariance matrix(Ex) after rotation.

Definition at line 163 of file Helix.cxx.

References cos(), delXDelA(), m_ac, m_cp, m_Ea, m_matrixValid, m_pivot, m_r, m_sp, sin(), and x().

                                            {
    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);
}

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

Definition at line 146 of file Helix.cxx.

References cos(), m_ac, m_cp, m_pivot, m_r, m_sp, and sin().

                                      {
    //
    // 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;
}

HepPoint3D Helix::x

(

double

dPhi = 0.

)

const

returns position after rotating angle dPhi in phi direction.

Definition at line 129 of file Helix.cxx.

References cos(), m_ac, m_cp, m_pivot, m_r, m_sp, and sin().

Referenced by TTrack::approach(), TTrack::approach2D(), TCurlFinder::distance(), TTrack::dxda(), EsTimeAlg::execute(), TTrack::fit2D(), TTrack::HelCyl(), RkFitCylinder::intersect(), FTFinder::makeMdst(), TRunge::SetFlightLength(), TofFz_helix::TofFz_Get(), updateCache(), KalmanFit::Helix::updateCache(), x(), and KalmanFit::Helix::x().

                         {
    //
    // 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);
}

---

Member Data Documentation

const double Helix::ConstantAlpha = 333.564095 [static]

Constant alpha for uniform field.

Definition at line 171 of file Helix.h.

HepVector Helix::m_a [private]

Definition at line 177 of file Helix.h.

Referenced by a(), KalmanFit::Helix::a(), cosTheta(), Helix(), operator=(), KalmanFit::Helix::operator=(), pivot(), KalmanFit::Helix::pivot(), set(), KalmanFit::Helix::set(), updateCache(), and KalmanFit::Helix::updateCache().

double Helix::m_ac[5] [private]

Definition at line 187 of file Helix.h.

Referenced by del4MDelA(), KalmanFit::Helix::del4MDelA(), del4MXDelA(), KalmanFit::Helix::del4MXDelA(), delApDelA(), KalmanFit::Helix::delApDelA(), delMDelA(), KalmanFit::Helix::delMDelA(), delXDelA(), KalmanFit::Helix::delXDelA(), dr(), KalmanFit::Helix::dr(), dz(), KalmanFit::Helix::dz(), kappa(), KalmanFit::Helix::kappa(), momentum(), KalmanFit::Helix::momentum(), operator=(), KalmanFit::Helix::operator=(), phi0(), KalmanFit::Helix::phi0(), pivot(), KalmanFit::Helix::pivot(), tanl(), KalmanFit::Helix::tanl(), updateCache(), KalmanFit::Helix::updateCache(), x(), and KalmanFit::Helix::x().

double Helix::m_alpha [protected]

Definition at line 164 of file Helix.h.

Referenced by KalmanFit::Helix::alpha(), bFieldZ(), KalmanFit::Helix::bFieldZ(), Helix(), operator=(), KalmanFit::Helix::operator=(), updateCache(), and KalmanFit::Helix::updateCache().

double Helix::m_bField [protected]

Definition at line 163 of file Helix.h.

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

HepPoint3D Helix::m_center [private]

Definition at line 182 of file Helix.h.

Referenced by center(), KalmanFit::Helix::center(), operator=(), KalmanFit::Helix::operator=(), updateCache(), and KalmanFit::Helix::updateCache().

double Helix::m_cp [private]

Definition at line 183 of file Helix.h.

Referenced by cosPhi0(), KalmanFit::Helix::cosPhi0(), del4MXDelA(), KalmanFit::Helix::del4MXDelA(), delXDelA(), KalmanFit::Helix::delXDelA(), momentum(), KalmanFit::Helix::momentum(), operator=(), KalmanFit::Helix::operator=(), updateCache(), KalmanFit::Helix::updateCache(), x(), and KalmanFit::Helix::x().

HepSymMatrix Helix::m_Ea [private]

Definition at line 178 of file Helix.h.

Referenced by Ea(), KalmanFit::Helix::Ea(), ignoreErrorMatrix(), KalmanFit::Helix::ignoreErrorMatrix(), momentum(), KalmanFit::Helix::momentum(), operator=(), KalmanFit::Helix::operator=(), pivot(), KalmanFit::Helix::pivot(), set(), KalmanFit::Helix::set(), x(), and KalmanFit::Helix::x().

bool Helix::m_matrixValid [private]

Definition at line 179 of file Helix.h.

Referenced by ignoreErrorMatrix(), KalmanFit::Helix::ignoreErrorMatrix(), momentum(), KalmanFit::Helix::momentum(), operator=(), KalmanFit::Helix::operator=(), pivot(), KalmanFit::Helix::pivot(), set(), KalmanFit::Helix::set(), x(), and KalmanFit::Helix::x().

HepPoint3D Helix::m_pivot [private]

Definition at line 176 of file Helix.h.

Referenced by momentum(), KalmanFit::Helix::momentum(), operator=(), KalmanFit::Helix::operator=(), pivot(), KalmanFit::Helix::pivot(), set(), KalmanFit::Helix::set(), updateCache(), KalmanFit::Helix::updateCache(), x(), and KalmanFit::Helix::x().

IMagneticFieldSvc* Helix::m_pmgnIMF [protected]

Definition at line 162 of file Helix.h.

Referenced by Helix().

double Helix::m_pt [private]

Definition at line 185 of file Helix.h.

Referenced by momentum(), KalmanFit::Helix::momentum(), operator=(), KalmanFit::Helix::operator=(), pt(), updateCache(), and KalmanFit::Helix::updateCache().

double Helix::m_r [private]

Definition at line 186 of file Helix.h.

Referenced by curv(), KalmanFit::Helix::curv(), del4MXDelA(), KalmanFit::Helix::del4MXDelA(), delApDelA(), KalmanFit::Helix::delApDelA(), delXDelA(), KalmanFit::Helix::delXDelA(), momentum(), KalmanFit::Helix::momentum(), operator=(), KalmanFit::Helix::operator=(), pivot(), KalmanFit::Helix::pivot(), radius(), KalmanFit::Helix::radius(), updateCache(), KalmanFit::Helix::updateCache(), x(), and KalmanFit::Helix::x().

double Helix::m_sp [private]

Definition at line 184 of file Helix.h.

Referenced by del4MXDelA(), KalmanFit::Helix::del4MXDelA(), delXDelA(), KalmanFit::Helix::delXDelA(), momentum(), KalmanFit::Helix::momentum(), operator=(), KalmanFit::Helix::operator=(), sinPhi0(), KalmanFit::Helix::sinPhi0(), updateCache(), KalmanFit::Helix::updateCache(), x(), and KalmanFit::Helix::x().

---