#include <PixelVertexFinding/interface/PixelVertexProducer.h>

Inheritance diagram for PixelVertexProducer:

Public Member Functions
	PixelVertexProducer (const edm::ParameterSet &)
virtual void	produce (edm::Event &, const edm::EventSetup &)
	~PixelVertexProducer ()
Private Attributes
edm::ParameterSet	conf_
DivisiveVertexFinder *	dvf_
double	ptMin_
int	verbose_

Detailed Description

Description: This produces 1D (z only) primary vertexes using only pixel information.

Implementation: This producer can use either the Divisive Primary Vertex Finder or the Histogramming Primary Vertex Finder (currently not implemented). It relies on the PixelTripletProducer and PixelTrackProducer having already been run upstream. This is code ported from ORCA originally written by S Cucciarelli, M Konecki, D Kotlinski.

Definition at line 34 of file PixelVertexProducer.h.

Constructor & Destructor Documentation

PixelVertexProducer::PixelVertexProducer ( const edm::ParameterSet & conf ) [explicit]

Definition at line 13 of file PixelVertexProducer.cc.

References conf_, dvf_, edm::ParameterSet::getParameter(), ptMin_, and verbose_.

  : conf_(conf), verbose_(0), dvf_(0), ptMin_(1.0)
{
  // Register my product
  produces<reco::VertexCollection>();

  // Setup shop
  verbose_           = conf.getParameter<int>("Verbosity"); // 0 silent, 1 chatty, 2 loud
  std::string finder = conf.getParameter<std::string>("Finder"); // DivisiveVertexFinder
  bool useError      = conf.getParameter<bool>("UseError"); // true
  bool wtAverage     = conf.getParameter<bool>("WtAverage"); // true
  double zOffset     = conf.getParameter<double>("ZOffset"); // 5.0 sigma
  double zSeparation = conf.getParameter<double>("ZSeparation"); // 0.05 cm
  int ntrkMin        = conf.getParameter<int>("NTrkMin"); // 3
  // Tracking requirements before sending a track to be considered for vtx
  ptMin_ = conf_.getParameter<double>("PtMin"); // 1.0 GeV

  if (finder == "DivisiveVertexFinder") {
    if (verbose_ > 0) edm::LogInfo("PixelVertexProducer") << ": Using the DivisiveVertexFinder\n";
    dvf_ = new DivisiveVertexFinder(zOffset, ntrkMin, useError, zSeparation, wtAverage, verbose_);
  }
  else { // Finder not supported, or you made a mistake in your request
    // throw an exception once I figure out how CMSSW does this
  }
}

PixelVertexProducer::~PixelVertexProducer ( )

Definition at line 40 of file PixelVertexProducer.cc.

References dvf_.

                                          {
  delete dvf_;
}

Member Function Documentation

void PixelVertexProducer::produce	(	edm::Event &	e,
		const edm::EventSetup &	es
	)		`[virtual]`

Implements edm::EDProducer.

Definition at line 44 of file PixelVertexProducer.cc.

References reco::Vertex::add(), ExpressReco_HICollisions_FallBack::chi2, conf_, dvf_, reco::BeamSpot::dxdz(), reco::BeamSpot::dydz(), error, DivisiveVertexFinder::findVertexes(), DivisiveVertexFinder::findVertexesAlt(), edm::Event::getByLabel(), edm::ParameterSet::getParameter(), i, edm::HandleBase::isValid(), convertSQLiteXML::ok, edm::Handle< T >::product(), ExpressReco_HICollisions_FallBack::pt, ptMin_, edm::RefVector< C, T, F >::push_back(), edm::Event::put(), edm::RefVector< C, T, F >::size(), mathSSE::sqrt(), ExpressReco_HICollisions_FallBack::trackCollection, ExpressReco_HICollisions_FallBack::trackCollName, testEve_cfg::tracks, v, verbose_, ExpressReco_HICollisions_FallBack::x, reco::BeamSpot::x0(), ExpressReco_HICollisions_FallBack::y, reco::BeamSpot::y0(), z, and reco::BeamSpot::z0().

                                                                      {

  // First fish the pixel tracks out of the event
  edm::Handle<reco::TrackCollection> trackCollection;
  edm::InputTag trackCollName = conf_.getParameter<edm::InputTag>("TrackCollection");
  e.getByLabel(trackCollName,trackCollection);
  const reco::TrackCollection tracks = *(trackCollection.product());
  if (verbose_ > 0) edm::LogInfo("PixelVertexProducer") << ": Found " << tracks.size() << " tracks in TrackCollection called " << trackCollName << "\n";
  

  // Second, make a collection of pointers to the tracks we want for the vertex finder
  reco::TrackRefVector trks;
  for (unsigned int i=0; i<tracks.size(); i++) {
    if (tracks[i].pt() > ptMin_)     
      trks.push_back( reco::TrackRef(trackCollection, i) );
  }
  if (verbose_ > 0) edm::LogInfo("PixelVertexProducer") << ": Selected " << trks.size() << " of these tracks for vertexing\n";

  edm::Handle<reco::BeamSpot> bsHandle;
  edm::InputTag bsName = conf_.getParameter<edm::InputTag>("beamSpot");
  e.getByLabel(bsName,bsHandle);
  math::XYZPoint myPoint(0.,0.,0.);
  if (bsHandle.isValid()) myPoint = math::XYZPoint(bsHandle->x0(),bsHandle->y0(), 0. ); //FIXME: fix last coordinate with vertex.z() at same time

  // Third, ship these tracks off to be vertexed
  std::auto_ptr<reco::VertexCollection> vertexes(new reco::VertexCollection);
  bool ok;
  if (conf_.getParameter<bool>("Method2")) {
    ok = dvf_->findVertexesAlt(trks,       // input
                             *vertexes,myPoint); // output
    if (verbose_ > 0) edm::LogInfo("PixelVertexProducer") << "Method2 returned status of " << ok;
  }
  else {
    ok = dvf_->findVertexes(trks,       // input
                            *vertexes); // output
    if (verbose_ > 0) edm::LogInfo("PixelVertexProducer") << "Method1 returned status of " << ok;
  }

  if (verbose_ > 0) {
    edm::LogInfo("PixelVertexProducer") << ": Found " << vertexes->size() << " vertexes\n";
    for (unsigned int i=0; i<vertexes->size(); ++i) {
      edm::LogInfo("PixelVertexProducer") << "Vertex number " << i << " has " << (*vertexes)[i].tracksSize() << " tracks with a position of " << (*vertexes)[i].z() << " +- " << std::sqrt( (*vertexes)[i].covariance(2,2) );
    }
  }


  if(bsHandle.isValid())
   {
    const reco::BeamSpot & bs = *bsHandle;

    for (unsigned int i=0; i<vertexes->size(); ++i) {
      double z=(*vertexes)[i].z();
      double x=bs.x0()+bs.dxdz()*(z-bs.z0());
      double y=bs.y0()+bs.dydz()*(z-bs.z0()); 
      reco::Vertex v( reco::Vertex::Point(x,y,z), (*vertexes)[i].error(),(*vertexes)[i].chi2() , (*vertexes)[i].ndof() , (*vertexes)[i].tracksSize());
       //Copy also the tracks 
       for (std::vector<reco::TrackBaseRef >::const_iterator it = (*vertexes)[i].tracks_begin();
            it !=(*vertexes)[i].tracks_end(); it++) {
            v.add( *it );
       }
      (*vertexes)[i]=v;

    }
  }
   else
  {
      edm::LogWarning("PixelVertexProducer") << "No beamspot found. Using returning vertexes with (0,0,Z) ";
  } 

  e.put(vertexes);
}