PixelNtupletsFitter Class Reference

#include <PixelNtupletsFitter.h>

Inheritance diagram for PixelNtupletsFitter:

Public Member Functions
	PixelNtupletsFitter (float nominalB, const MagneticField *field, bool useRiemannFit)
std::unique_ptr< reco::Track >	run (const std::vector< const TrackingRecHit *> &hits, const TrackingRegion &region) const override
	~PixelNtupletsFitter () override=default
Public Member Functions inherited from PixelFitterBase
virtual	~PixelFitterBase ()

Private Attributes
const MagneticField *	field_
float	nominalB_
bool	useRiemannFit_

Detailed Description

Definition at line 12 of file PixelNtupletsFitter.h.

Constructor & Destructor Documentation

PixelNtupletsFitter()

PixelNtupletsFitter::PixelNtupletsFitter ( float  nominalB, const MagneticField *  field, bool  useRiemannFit  )

explicit

Definition at line 22 of file PixelNtupletsFitter.cc.

    : nominalB_(nominalB), field_(field), useRiemannFit_(useRiemannFit) {}

~PixelNtupletsFitter()

PixelNtupletsFitter::~PixelNtupletsFitter ( )

overridedefault

Member Function Documentation

run()

std::unique_ptr< reco::Track > PixelNtupletsFitter::run ( const std::vector< const TrackingRecHit *> &  hits, const TrackingRegion &  region  ) const

overridevirtual

Implements PixelFitterBase.

Definition at line 25 of file PixelNtupletsFitter.cc.

References cms::cuda::assert(), PixelTrackBuilder::build(), hltPixelTracks_cff::chi2, riemannFit::HelixFit::chi2_circle, riemannFit::HelixFit::chi2_line, riemannFit::HelixFit::cov, declareDynArray, field_, brokenline::helixFit(), riemannFit::helixFit(), hfClusterShapes_cfi::hits, mps_fire::i, PixelPluginsPhase0_cfi::isBarrel, nhits, nominalB_, riemannFit::HelixFit::par, phi, hiPixelPairStep_cff::points, DiDispStaMuonMonitor_cfi::pt, riemannFit::HelixFit::qCharge, rpcPointValidation_cfi::recHit, HLT_2023v12_cff::region, runTheMatrix::ret, mathSSE::sqrt(), qcdUeDQM_cfi::tip, useRiemannFit_, and ComparisonHelper::zip().

                                                                                          {
  using namespace riemannFit;

  std::unique_ptr<reco::Track> ret;

  unsigned int nhits = hits.size();

  if (nhits < 2)
    return ret;

  declareDynArray(GlobalPoint, nhits, points);
  declareDynArray(GlobalError, nhits, errors);
  declareDynArray(bool, nhits, isBarrel);

  for (unsigned int i = 0; i != nhits; ++i) {
    auto const& recHit = hits[i];
    points[i] = GlobalPoint(recHit->globalPosition().basicVector() - region.origin().basicVector());
    errors[i] = recHit->globalPositionError();
    isBarrel[i] = recHit->detUnit()->type().isBarrel();
  }

  assert(nhits == 4);
  riemannFit::Matrix3xNd<4> hits_gp;

  Eigen::Matrix<float, 6, 4> hits_ge = Eigen::Matrix<float, 6, 4>::Zero();

  for (unsigned int i = 0; i < nhits; ++i) {
    hits_gp.col(i) << points[i].x(), points[i].y(), points[i].z();

    hits_ge.col(i) << errors[i].cxx(), errors[i].cyx(), errors[i].cyy(), errors[i].czx(), errors[i].czy(),
        errors[i].czz();
  }

  HelixFit fittedTrack = useRiemannFit_ ? riemannFit::helixFit(hits_gp, hits_ge, nominalB_, true)
                                        : brokenline::helixFit(hits_gp, hits_ge, nominalB_);

  int iCharge = fittedTrack.qCharge;

  // parameters are:
  // 0: phi
  // 1: tip
  // 2: curvature
  // 3: cottheta
  // 4: zip
  float valPhi = fittedTrack.par(0);

  float valTip = fittedTrack.par(1);

  float valCotTheta = fittedTrack.par(3);

  float valZip = fittedTrack.par(4);
  float valPt = fittedTrack.par(2);
  //
  //  PixelTrackErrorParam param(valEta, valPt);
  float errValPhi = std::sqrt(fittedTrack.cov(0, 0));
  float errValTip = std::sqrt(fittedTrack.cov(1, 1));

  float errValPt = std::sqrt(fittedTrack.cov(2, 2));

  float errValCotTheta = std::sqrt(fittedTrack.cov(3, 3));
  float errValZip = std::sqrt(fittedTrack.cov(4, 4));

  float chi2 = fittedTrack.chi2_line + fittedTrack.chi2_circle;

  PixelTrackBuilder builder;
  Measurement1D phi(valPhi, errValPhi);
  Measurement1D tip(valTip, errValTip);

  Measurement1D pt(valPt, errValPt);
  Measurement1D cotTheta(valCotTheta, errValCotTheta);
  Measurement1D zip(valZip, errValZip);

  ret.reset(builder.build(pt, phi, cotTheta, tip, zip, chi2, iCharge, hits, field_, region.origin()));
  return ret;
}

Member Data Documentation

field_

const MagneticField* PixelNtupletsFitter::field_

private

Definition at line 21 of file PixelNtupletsFitter.h.

Referenced by run().

nominalB_

float PixelNtupletsFitter::nominalB_

private

Definition at line 20 of file PixelNtupletsFitter.h.

Referenced by run().

useRiemannFit_

bool PixelNtupletsFitter::useRiemannFit_

private

Definition at line 22 of file PixelNtupletsFitter.h.

Referenced by run().