PixelHitMatcher Class Reference

#include <PixelHitMatcher.h>

Classes
struct	BarrelMeasurementEstimator
struct	ForwardMeasurementEstimator

Public Member Functions
std::vector< SeedWithInfo >	operator() (const std::vector< const TrajectorySeedCollection * > &seedsV, const GlobalPoint &xmeas, const GlobalPoint &vprim, float energy, int charge) const
	PixelHitMatcher (float phi1min, float phi1max, float phi2minB, float phi2maxB, float phi2minF, float phi2maxF, float z2maxB, float r2maxF, float rMaxI, bool useRecoVertex)
void	set1stLayer (float dummyphi1min, float dummyphi1max)
void	set1stLayerZRange (float zmin1, float zmax1)
void	set2ndLayer (float dummyphi2minB, float dummyphi2maxB, float dummyphi2minF, float dummyphi2maxF)
void	setES (MagneticField const &, TrackerGeometry const &trackerGeometry)

Private Attributes
BarrelMeasurementEstimator	meas1stBLayer
ForwardMeasurementEstimator	meas1stFLayer
BarrelMeasurementEstimator	meas2ndBLayer
ForwardMeasurementEstimator	meas2ndFLayer
std::unique_ptr< PropagatorWithMaterial >	prop1stLayer = nullptr
std::unique_ptr< PropagatorWithMaterial >	prop2ndLayer = nullptr
const MagneticField *	theMagField
const TrackerGeometry *	theTrackerGeometry
const bool	useRecoVertex_

Detailed Description

Description: Class to match an ECAL cluster to the pixel hits. Two compatible hits in the pixel layers are required.

Implementation: future redesign

Definition at line 44 of file PixelHitMatcher.h.

Constructor & Destructor Documentation

PixelHitMatcher()

PixelHitMatcher::PixelHitMatcher	(	float	phi1min,
		float	phi1max,
		float	phi2minB,
		float	phi2maxB,
		float	phi2minF,
		float	phi2maxF,
		float	z2maxB,
		float	r2maxF,
		float	rMaxI,
		bool	useRecoVertex
	)

Definition at line 63 of file PixelHitMatcher.cc.

    :  //zmin1 and zmax1 are dummy at this moment, set from beamspot later
      meas1stBLayer{phi1min, phi1max, 0., 0.},
      meas2ndBLayer{phi2minB, phi2maxB, -z2maxB, z2maxB},
      meas1stFLayer{phi1min, phi1max, 0., 0., -rMaxI, rMaxI},
      meas2ndFLayer{phi2minF, phi2maxF, -r2maxF, r2maxF, -rMaxI, rMaxI},
      useRecoVertex_(useRecoVertex) {}

Member Function Documentation

operator()()

std::vector< SeedWithInfo > PixelHitMatcher::operator()	(	const std::vector< const TrajectorySeedCollection * > &	seedsV,
		const GlobalPoint &	xmeas,
		const GlobalPoint &	vprim,
		float	energy,
		int	charge
	)		const

Definition at line 109 of file PixelHitMatcher.cc.

                                                                        {
  auto xmeas_r = xmeas.perp();
 
  const float phicut = std::cos(2.5);
 
  auto fts = trackingTools::ftsFromVertexToPoint(*theMagField, xmeas, vprim, energy, charge);
  PerpendicularBoundPlaneBuilder bpb;
  TrajectoryStateOnSurface tsos(fts, *bpb(fts.position(), fts.momentum()));
 
  std::vector<SeedWithInfo> result;
  unsigned int allSeedsSize = 0;
  for (auto const sc : seedsV)
    allSeedsSize += sc->size();
 
  IntGlobalPointPairUnorderedMap<TrajectoryStateOnSurface> mapTsos2Fast(allSeedsSize);
 
  auto ndets = theTrackerGeometry->dets().size();
 
  int iTsos[ndets];
  for (auto &i : iTsos)
    i = -1;
  std::vector<TrajectoryStateOnSurface> vTsos;
  vTsos.reserve(allSeedsSize);
 
  std::vector<GlobalPoint> hitGpMap;
  for (const auto seeds : seedsV) {
    for (const auto &seed : *seeds) {
      hitGpMap.clear();
      if (seed.nHits() > 9) {
        edm::LogWarning("GsfElectronAlgo|UnexpectedSeed") << "We cannot deal with seeds having more than 9 hits.";
        continue;
      }
 
      auto const &hits = seed.recHits();
      // cache the global points
 
      for (auto const &hit : hits) {
        hitGpMap.emplace_back(hit.globalPosition());
      }
 
      //iterate on the hits
      auto he = hits.end() - 1;
      for (auto it1 = hits.begin(); it1 < he; ++it1) {
        if (!it1->isValid())
          continue;
        auto idx1 = std::distance(hits.begin(), it1);
        const DetId id1 = it1->geographicalId();
        const GeomDet *geomdet1 = it1->det();
 
        auto ix1 = geomdet1->gdetIndex();
 
        /*  VI: this generates regression (other cut is just in phi). in my opinion it is safe and makes sense
            auto away = geomdet1->position().basicVector().dot(xmeas.basicVector()) <0;
            if (away) continue;
        */
 
        const GlobalPoint &hit1Pos = hitGpMap[idx1];
        auto dt = hit1Pos.x() * xmeas.x() + hit1Pos.y() * xmeas.y();
        if (dt < 0)
          continue;
        if (dt < phicut * (xmeas_r * hit1Pos.perp()))
          continue;
 
        if (iTsos[ix1] < 0) {
          iTsos[ix1] = vTsos.size();
          vTsos.push_back(prop1stLayer->propagate(tsos, geomdet1->surface()));
        }
        auto tsos1 = &vTsos[iTsos[ix1]];
 
        if (!tsos1->isValid())
          continue;
        bool est = id1.subdetId() % 2 ? meas1stBLayer(vprim, *tsos1, hit1Pos, charge)
                                      : meas1stFLayer(vprim, *tsos1, hit1Pos, charge);
        if (!est)
          continue;
        EleRelPointPair pp1(hit1Pos, tsos1->globalParameters().position(), vprim);
        const math::XYZPoint relHit1Pos(hit1Pos - vprim), relTSOSPos(tsos1->globalParameters().position() - vprim);
        const int subDet1 = id1.subdetId();
        const float dRz1 = (id1.subdetId() % 2 ? pp1.dZ() : pp1.dPerp());
        const float dPhi1 = pp1.dPhi();
        // setup our vertex
        double zVertex;
        if (!useRecoVertex_) {
          // we don't know the z vertex position, get it from linear extrapolation
          // compute the z vertex from the cluster point and the found pixel hit
          const double pxHit1z = hit1Pos.z();
          const double pxHit1x = hit1Pos.x();
          const double pxHit1y = hit1Pos.y();
          const double r1diff =
              std::sqrt((pxHit1x - vprim.x()) * (pxHit1x - vprim.x()) + (pxHit1y - vprim.y()) * (pxHit1y - vprim.y()));
          const double r2diff =
              std::sqrt((xmeas.x() - pxHit1x) * (xmeas.x() - pxHit1x) + (xmeas.y() - pxHit1y) * (xmeas.y() - pxHit1y));
          zVertex = pxHit1z - r1diff * (xmeas.z() - pxHit1z) / r2diff;
        } else {
          // here use rather the reco vertex z position
          zVertex = vprim.z();
        }
        GlobalPoint vertex(vprim.x(), vprim.y(), zVertex);
        auto fts2 = trackingTools::ftsFromVertexToPoint(*theMagField, hit1Pos, vertex, energy, charge);
        // now find the matching hit
        for (auto it2 = it1 + 1; it2 != hits.end(); ++it2) {
          if (!it2->isValid())
            continue;
          auto idx2 = std::distance(hits.begin(), it2);
          const DetId id2 = it2->geographicalId();
          const GeomDet *geomdet2 = it2->det();
          const auto det_key = std::make_pair(geomdet2->gdetIndex(), hit1Pos);
          const TrajectoryStateOnSurface *tsos2;
          auto tsos2_itr = mapTsos2Fast.find(det_key);
          if (tsos2_itr != mapTsos2Fast.end()) {
            tsos2 = &(tsos2_itr->second);
          } else {
            auto empl_result = mapTsos2Fast.emplace(det_key, prop2ndLayer->propagate(fts2, geomdet2->surface()));
            tsos2 = &(empl_result.first->second);
          }
          if (!tsos2->isValid())
            continue;
          const GlobalPoint &hit2Pos = hitGpMap[idx2];
          bool est2 = id2.subdetId() % 2 ? meas2ndBLayer(vertex, *tsos2, hit2Pos, charge)
                                         : meas2ndFLayer(vertex, *tsos2, hit2Pos, charge);
          if (est2) {
            EleRelPointPair pp2(hit2Pos, tsos2->globalParameters().position(), vertex);
            const int subDet2 = id2.subdetId();
            const float dRz2 = (subDet2 % 2 == 1) ? pp2.dZ() : pp2.dPerp();
            const float dPhi2 = pp2.dPhi();
            const unsigned char hitsMask = (1 << idx1) | (1 << idx2);
            result.push_back({seed, hitsMask, subDet2, dRz2, dPhi2, subDet1, dRz1, dPhi1});
          }
        }  // inner loop on hits
      }    // outer loop on hits
    }      // loop on seeds
  }        //loop on vector of seeds
 
  return result;
}

References ALCARECOTkAlJpsiMuMu_cff::charge, funct::cos(), TrackerGeometry::dets(), HLT_FULL_cff::distance, dt, HCALHighEnergyHPDFilter_cfi::energy, trackingTools::ftsFromVertexToPoint(), GeomDet::gdetIndex(), hcalSimParameters_cfi::he, hfClusterShapes_cfi::hits, mps_fire::i, globals_cff::id1, globals_cff::id2, meas1stBLayer, meas1stFLayer, meas2ndBLayer, meas2ndFLayer, PV3DBase< T, PVType, FrameType >::perp(), prop1stLayer, prop2ndLayer, mps_fire::result, fileCollector::seed, InitialStep_cff::seeds, mathSSE::sqrt(), GeomDet::surface(), theMagField, theTrackerGeometry, useRecoVertex_, bphysicsOniaDQM_cfi::vertex, PV3DBase< T, PVType, FrameType >::x(), PV3DBase< T, PVType, FrameType >::y(), PV3DBase< T, PVType, FrameType >::z(), and HLT_FULL_cff::zVertex.

set1stLayer()

void PixelHitMatcher::set1stLayer	(	float	dummyphi1min,
		float	dummyphi1max
	)

Definition at line 80 of file PixelHitMatcher.cc.

                                                                        {
  meas1stBLayer.thePhiMin = dummyphi1min;
  meas1stBLayer.thePhiMax = dummyphi1max;
  meas1stFLayer.thePhiMin = dummyphi1min;
  meas1stFLayer.thePhiMax = dummyphi1max;
}

References meas1stBLayer, meas1stFLayer, PixelHitMatcher::BarrelMeasurementEstimator::thePhiMax, PixelHitMatcher::ForwardMeasurementEstimator::thePhiMax, PixelHitMatcher::BarrelMeasurementEstimator::thePhiMin, and PixelHitMatcher::ForwardMeasurementEstimator::thePhiMin.

Referenced by ElectronSeedGenerator::seedsFromThisCluster().

set1stLayerZRange()

void PixelHitMatcher::set1stLayerZRange	(	float	zmin1,
		float	zmax1
	)

Definition at line 87 of file PixelHitMatcher.cc.

                                                                {
  meas1stBLayer.theZMin = zmin1;
  meas1stBLayer.theZMax = zmax1;
  meas1stFLayer.theRMin = zmin1;
  meas1stFLayer.theRMax = zmax1;
}

References meas1stBLayer, meas1stFLayer, PixelHitMatcher::ForwardMeasurementEstimator::theRMax, PixelHitMatcher::ForwardMeasurementEstimator::theRMin, PixelHitMatcher::BarrelMeasurementEstimator::theZMax, and PixelHitMatcher::BarrelMeasurementEstimator::theZMin.

Referenced by ElectronSeedGenerator::seedsFromThisCluster().

set2ndLayer()

void PixelHitMatcher::set2ndLayer	(	float	dummyphi2minB,
		float	dummyphi2maxB,
		float	dummyphi2minF,
		float	dummyphi2maxF
	)

Definition at line 94 of file PixelHitMatcher.cc.

                                                                                                                    {
  meas2ndBLayer.thePhiMin = dummyphi2minB;
  meas2ndBLayer.thePhiMax = dummyphi2maxB;
  meas2ndFLayer.thePhiMin = dummyphi2minF;
  meas2ndFLayer.thePhiMax = dummyphi2maxF;
}

References meas2ndBLayer, meas2ndFLayer, PixelHitMatcher::BarrelMeasurementEstimator::thePhiMax, PixelHitMatcher::ForwardMeasurementEstimator::thePhiMax, PixelHitMatcher::BarrelMeasurementEstimator::thePhiMin, and PixelHitMatcher::ForwardMeasurementEstimator::thePhiMin.

Referenced by ElectronSeedGenerator::seedsFromThisCluster().

setES()

void PixelHitMatcher::setES	(	MagneticField const &	magField,
		TrackerGeometry const &	trackerGeometry
	)

Definition at line 101 of file PixelHitMatcher.cc.

                                                                                                 {
  theMagField = &magField;
  theTrackerGeometry = &trackerGeometry;
  constexpr float mass = .000511;  // electron propagation
  prop1stLayer = std::make_unique<PropagatorWithMaterial>(oppositeToMomentum, mass, theMagField);
  prop2ndLayer = std::make_unique<PropagatorWithMaterial>(alongMomentum, mass, theMagField);
}

References alongMomentum, EgHLTOffHistBins_cfi::mass, oppositeToMomentum, prop1stLayer, prop2ndLayer, theMagField, and theTrackerGeometry.

Referenced by ElectronSeedGenerator::setupES().

Member Data Documentation

meas1stBLayer

BarrelMeasurementEstimator PixelHitMatcher::meas1stBLayer

private

Definition at line 90 of file PixelHitMatcher.h.

Referenced by operator()(), set1stLayer(), and set1stLayerZRange().

meas1stFLayer

ForwardMeasurementEstimator PixelHitMatcher::meas1stFLayer

private

Definition at line 92 of file PixelHitMatcher.h.

Referenced by operator()(), set1stLayer(), and set1stLayerZRange().

meas2ndBLayer

BarrelMeasurementEstimator PixelHitMatcher::meas2ndBLayer

private

Definition at line 91 of file PixelHitMatcher.h.

Referenced by operator()(), and set2ndLayer().

meas2ndFLayer

ForwardMeasurementEstimator PixelHitMatcher::meas2ndFLayer

private

Definition at line 93 of file PixelHitMatcher.h.

Referenced by operator()(), and set2ndLayer().

prop1stLayer

std::unique_ptr<PropagatorWithMaterial> PixelHitMatcher::prop1stLayer = nullptr

private

Definition at line 94 of file PixelHitMatcher.h.

Referenced by operator()(), and setES().

prop2ndLayer

std::unique_ptr<PropagatorWithMaterial> PixelHitMatcher::prop2ndLayer = nullptr

private

Definition at line 95 of file PixelHitMatcher.h.

Referenced by operator()(), and setES().

theMagField

const MagneticField* PixelHitMatcher::theMagField

private

Definition at line 96 of file PixelHitMatcher.h.

Referenced by operator()(), and setES().

theTrackerGeometry

const TrackerGeometry* PixelHitMatcher::theTrackerGeometry

private

Definition at line 97 of file PixelHitMatcher.h.

Referenced by operator()(), and setES().

useRecoVertex_

const bool PixelHitMatcher::useRecoVertex_

private

Definition at line 98 of file PixelHitMatcher.h.

Referenced by operator()().