tmtt::ChiSquaredFit4 Class Reference

#include <ChiSquaredFit4.h>

Inheritance diagram for tmtt::ChiSquaredFit4:

Public Member Functions
	ChiSquaredFit4 (const Settings *settings, const uint nPar)
Public Member Functions inherited from tmtt::ChiSquaredFitBase
	ChiSquaredFitBase (const Settings *settings, const uint nPar)
L1fittedTrack	fit (const L1track3D &l1track3D) override
Public Member Functions inherited from tmtt::TrackFitGeneric
	TrackFitGeneric (const Settings *settings, const std::string &fitterName="")
virtual	~TrackFitGeneric ()=default

Protected Member Functions
TMatrixD	D (const TVectorD &x) override
TVectorD	residuals (const TVectorD &x) override
TVectorD	seed (const L1track3D &l1track3D) override
TMatrixD	Vinv () override

Additional Inherited Members
Public Types inherited from tmtt::ChiSquaredFitBase
enum	PAR_IDS {   INVR, PHI0, T, Z0,   D0 }
Protected Attributes inherited from tmtt::ChiSquaredFitBase
double	chiSq_
int	ilargestresid_
float	largestresid_
uint	nPar_
double	qOverPt_seed_
std::vector< Stub * >	stubs_
TVectorD	trackParams_
Protected Attributes inherited from tmtt::TrackFitGeneric
const std::string	fitterName_
const Settings *	settings_

Detailed Description

Definition at line 8 of file ChiSquaredFit4.h.

Constructor & Destructor Documentation

ChiSquaredFit4()

tmtt::ChiSquaredFit4::ChiSquaredFit4	(	const Settings *	settings,
		const uint	nPar
	)

Definition at line 8 of file ChiSquaredFit4.cc.

References tmtt::ChiSquaredFitBase::ilargestresid_, and tmtt::ChiSquaredFitBase::largestresid_.

                                                                          : ChiSquaredFitBase(settings, nPar) {
    largestresid_ = -1.0;
    ilargestresid_ = -1;
  }

Member Function Documentation

D()

TMatrixD tmtt::ChiSquaredFit4::D ( const TVectorD &  x )

overrideprotectedvirtual

Implements tmtt::ChiSquaredFitBase.

Definition at line 24 of file ChiSquaredFit4.cc.

References Reference_intrackfit_cff::barrel, mps_fire::i, tmtt::ChiSquaredFitBase::INVR, LEDCalibrationChannels::iphi, dqmiolumiharvest::j, tmtt::ChiSquaredFitBase::nPar_, tmtt::ChiSquaredFitBase::PHI0, tmtt::ChiSquaredFitBase::stubs_, tmtt::ChiSquaredFitBase::T, submitPVValidationJobs::t, ApeEstimator_cff::width, x, and tmtt::ChiSquaredFitBase::Z0.

                                              {
    TMatrixD D(2 * stubs_.size(), nPar_);  // Empty matrix
    D.Zero();
    int j = 0;
    double rInv = x[INVR];
    double phi0 = x[PHI0];
    double t = x[T];
    for (unsigned i = 0; i < stubs_.size(); i++) {
      double ri = stubs_[i]->r();
      if (stubs_[i]->barrel()) {
        // Derivatives of r*phi
        D(j, INVR) = -0.5 * ri * ri;
        D(j, PHI0) = ri;
        j++;
        // Derivatives of z
        D(j, T) = ri;
        D(j, Z0) = 1;
        j++;
      } else {
        double phii = stubs_[i]->phi();
        int iphi = stubs_[i]->iphi();

        // N.B. These represent HALF the width and number of strips of sensor.
        double width = 0.5 * stubs_[i]->trackerModule()->sensorWidth();
        double nstrip = 0.5 * stubs_[i]->nStrips();

        double Deltai = width * (iphi - nstrip) / nstrip;  // Non-radial endcap 2S strip correction
        if (stubs_[i]->z() > 0.0)
          Deltai = -Deltai;
        double DeltaiOverRi = Deltai / ri;
        double theta0 = DeltaiOverRi + (2. / 3.) * DeltaiOverRi * DeltaiOverRi * DeltaiOverRi;

        double phi_track = phi0 - 0.5 * rInv * ri;  //Expected phi hit given the track

        double tInv = 1 / t;
        // Derivatives of r
        D(j, INVR) = -1 * ri * ri * ri * rInv;
        D(j, PHI0) = 0;
        D(j, T) = -ri * tInv;
        D(j, Z0) = -1 * tInv;
        j++;
        // Derivatives of r*phi
        D(j, INVR) = -0.5 * ri * ri;
        D(j, PHI0) = ri;
        D(j, T) = ri * 0.5 * rInv * ri * tInv - ((phi_track - phii) - theta0) * ri * tInv;
        D(j, Z0) = ri * 0.5 * rInv * tInv - ((phi_track - phii) - theta0) * tInv;
        j++;
      }
    }
    return D;
  }

residuals()

TVectorD tmtt::ChiSquaredFit4::residuals ( const TVectorD &  x )

overrideprotectedvirtual

Implements tmtt::ChiSquaredFitBase.

Definition at line 101 of file ChiSquaredFit4.cc.

References funct::abs(), Reference_intrackfit_cff::barrel, dumpMFGeometry_cfg::delta, reco::deltaPhi(), mps_fire::i, tmtt::ChiSquaredFitBase::ilargestresid_, tmtt::ChiSquaredFitBase::INVR, LEDCalibrationChannels::iphi, dqmiolumiharvest::j, tmtt::Settings::kalmanMultiScattTerm(), tmtt::ChiSquaredFitBase::largestresid_, dqmiodumpmetadata::n, tmtt::ChiSquaredFitBase::PHI0, tmtt::ChiSquaredFitBase::qOverPt_seed_, tmtt::TrackFitGeneric::settings_, mathSSE::sqrt(), tmtt::ChiSquaredFitBase::stubs_, tmtt::ChiSquaredFitBase::T, submitPVValidationJobs::t, ApeEstimator_cff::width, x, tmtt::ChiSquaredFitBase::Z0, and HLTMuonOfflineAnalyzer_cfi::z0.

                                                      {
    unsigned int n = stubs_.size();

    TVectorD delta(2 * n);

    double rInv = x[INVR];
    double phi0 = x[PHI0];
    double t = x[T];
    double z0 = x[Z0];

    double chiSq = 0.0;

    unsigned int j = 0;

    largestresid_ = -1.0;
    ilargestresid_ = -1;

    // Scattering term scaling as 1/Pt.
    double sigmaScat = settings_->kalmanMultiScattTerm() * std::abs(qOverPt_seed_);

    for (unsigned int i = 0; i < n; i++) {
      double ri = stubs_[i]->r();
      double zi = stubs_[i]->z();
      double phii = stubs_[i]->phi();
      double sigmaPerp = stubs_[i]->sigmaPerp();
      double sigmaPar = stubs_[i]->sigmaPar();
      sigmaPerp = sqrt(sigmaPerp * sigmaPerp + sigmaScat * sigmaScat * ri * ri);

      if (stubs_[i]->barrel()) {
        double halfRinvRi = 0.5 * ri * rInv;
        double aSinHalfRinvRi = halfRinvRi + (2. / 3.) * halfRinvRi * halfRinvRi * halfRinvRi;
        double deltaphi = reco::deltaPhi(phi0 - aSinHalfRinvRi - phii, 0.);
        delta[j++] = (ri * deltaphi) / sigmaPerp;
        delta[j++] = (z0 + (2.0 / rInv) * t * aSinHalfRinvRi - zi) / sigmaPar;
      } else {
        double tInv = 1 / t;
        double r_track = (zi - z0) * tInv;
        double phi_track = phi0 - 0.5 * rInv * (zi - z0) * tInv;
        int iphi = stubs_[i]->iphi();

        // N.B. These represent HALF the width and number of strips of sensor.
        double width = 0.5 * stubs_[i]->trackerModule()->sensorWidth();
        double nstrip = 0.5 * stubs_[i]->nStrips();

        double Deltai = width * (iphi - nstrip) / nstrip;  // Non-radial endcap 2S strip correction

        if (stubs_[i]->z() > 0.0)
          Deltai = -Deltai;

        double DeltaiOverRi = Deltai / ri;
        double theta0 = DeltaiOverRi + (2. / 3.) * DeltaiOverRi * DeltaiOverRi * DeltaiOverRi;
        double Delta = Deltai - r_track * (theta0 - (phi_track - phii));

        delta[j++] = (r_track - ri) / sigmaPar;
        delta[j++] = Delta / sigmaPerp;
      }

      chiSq += delta[j - 2] * delta[j - 2] + delta[j - 1] * delta[j - 1];

      if (std::abs(delta[j - 2]) > largestresid_) {
        largestresid_ = std::abs(delta[j - 2]);
        ilargestresid_ = i;
      }

      if (std::abs(delta[j - 1]) > largestresid_) {
        largestresid_ = std::abs(delta[j - 1]);
        ilargestresid_ = i;
      }
    }

    return delta;
  }

seed()

TVectorD tmtt::ChiSquaredFit4::seed ( const L1track3D &  l1track3D )

overrideprotectedvirtual

Implements tmtt::ChiSquaredFitBase.

Definition at line 13 of file ChiSquaredFit4.cc.

References tmtt::Settings::invPtToInvR(), tmtt::ChiSquaredFitBase::INVR, tmtt::ChiSquaredFitBase::PHI0, tmtt::L1track3D::phi0(), tmtt::L1track3D::qOverPt(), tmtt::TrackFitGeneric::settings_, tmtt::ChiSquaredFitBase::T, tmtt::L1track3D::tanLambda(), x, tmtt::ChiSquaredFitBase::Z0, and tmtt::L1track3D::z0().

                                                          {
    TVectorD x(4);
    x[INVR] = settings_->invPtToInvR() * l1track3D.qOverPt();
    x[PHI0] = l1track3D.phi0();
    x[T] = l1track3D.tanLambda();
    x[Z0] = l1track3D.z0();
    return x;
  }

Vinv()

TMatrixD tmtt::ChiSquaredFit4::Vinv ( )

overrideprotectedvirtual

Implements tmtt::ChiSquaredFitBase.

Definition at line 79 of file ChiSquaredFit4.cc.

References funct::abs(), Reference_intrackfit_cff::barrel, mps_fire::i, tmtt::Settings::kalmanMultiScattTerm(), tmtt::ChiSquaredFitBase::qOverPt_seed_, tmtt::TrackFitGeneric::settings_, mathSSE::sqrt(), and tmtt::ChiSquaredFitBase::stubs_.

                                {
    TMatrixD Vinv(2 * stubs_.size(), 2 * stubs_.size());
    // Scattering term scaling as 1/Pt.
    double sigmaScat = settings_->kalmanMultiScattTerm() * std::abs(qOverPt_seed_);
    for (unsigned i = 0; i < stubs_.size(); i++) {
      double sigmaPerp = stubs_[i]->sigmaPerp();
      double sigmaPar = stubs_[i]->sigmaPar();
      double ri = stubs_[i]->r();
      sigmaPerp = sqrt(sigmaPerp * sigmaPerp + sigmaScat * sigmaScat * ri * ri);
      if (stubs_[i]->barrel()) {
        Vinv(2 * i, 2 * i) = 1 / sigmaPerp;
        Vinv(2 * i + 1, 2 * i + 1) = 1 / sigmaPar;
      } else {
        Vinv(2 * i, 2 * i) = 1 / sigmaPar;
        Vinv(2 * i + 1, 2 * i + 1) = 1 / sigmaPerp;
      }
    }
    return Vinv;
  }