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Public Types | Public Member Functions | Protected Member Functions | Protected Attributes

CSCPairResidualsConstraint Class Reference

#include <CSCPairResidualsConstraint.h>

Inheritance diagram for CSCPairResidualsConstraint:
CSCPairConstraint

List of all members.

Public Types

enum  { kModePhiy, kModePhiPos, kModePhiz, kModeRadius }

Public Member Functions

bool addTrack (const std::vector< TrajectoryMeasurement > &measurements, const reco::TransientTrack &track, const TrackTransformer *trackTransformer)
void configure (CSCOverlapsAlignmentAlgorithm *parent)
 CSCPairResidualsConstraint (unsigned int identifier, int i, int j, CSCDetId id_i, CSCDetId id_j)
double error () const
CSCDetId id_i () const
CSCDetId id_j () const
double radius (bool is_i) const
void read (std::vector< std::ifstream * > &input, std::vector< std::string > &filenames)
void setPropagator (const Propagator *propagator)
void setZplane (const CSCGeometry *cscGeometry)
bool valid () const
double value () const
void write (std::ofstream &output)
virtual ~CSCPairResidualsConstraint ()

Protected Member Functions

void calculatePhi (const TransientTrackingRecHit *hit, double &phi, double &phierr2, bool doRphi=false, bool globalPhi=false)
bool dphidzFromTrack (const std::vector< TrajectoryMeasurement > &measurements, const reco::TransientTrack &track, const TrackTransformer *trackTransformer, double &drphidz)
bool isFiducial (std::vector< const TransientTrackingRecHit * > &hits, bool is_i)

Protected Attributes

double m_averageRadius
const CSCGeometrym_cscGeometry
CSCDetId m_id_i
CSCDetId m_id_j
unsigned int m_identifier
double m_iZ
double m_iZ1
double m_iZ6
double m_jZ
double m_jZ1
double m_jZ6
TH1F * m_offsetResiduals
CSCOverlapsAlignmentAlgorithmm_parent
const Propagatorm_propagator
TH1F * m_radial
TH1F * m_slopeResiduals
double m_sum1
int m_sumN
double m_sumx
double m_sumxx
double m_sumxy
double m_sumy
double m_sumyy
double m_Zplane
Plane::PlanePointer m_Zsurface

Detailed Description

Date:
2010/05/27 19:40:03
Revision:
1.1
Author:
J. Pivarski - Texas A&M University <pivarski@physics.tamu.edu>

Definition at line 27 of file CSCPairResidualsConstraint.h.


Member Enumeration Documentation

anonymous enum
Enumerator:
kModePhiy 
kModePhiPos 
kModePhiz 
kModeRadius 

Definition at line 37 of file CSCPairResidualsConstraint.h.


Constructor & Destructor Documentation

CSCPairResidualsConstraint::CSCPairResidualsConstraint ( unsigned int  identifier,
int  i,
int  j,
CSCDetId  id_i,
CSCDetId  id_j 
) [inline]

Definition at line 29 of file CSCPairResidualsConstraint.h.

    : CSCPairConstraint(i, j, 0., 0.)
    , m_identifier(identifier), m_id_i(id_i), m_id_j(id_j)
    , m_sum1(0.), m_sumx(0.), m_sumy(0.), m_sumxx(0.), m_sumyy(0.), m_sumxy(0.), m_sumN(0)
    , m_Zplane(1000.), m_iZ1(1000.), m_iZ6(1000.), m_jZ1(1000.), m_jZ6(1000.), m_cscGeometry(NULL), m_propagator(NULL)
  {};
virtual CSCPairResidualsConstraint::~CSCPairResidualsConstraint ( ) [inline, virtual]

Definition at line 35 of file CSCPairResidualsConstraint.h.

{};

Member Function Documentation

bool CSCPairResidualsConstraint::addTrack ( const std::vector< TrajectoryMeasurement > &  measurements,
const reco::TransientTrack track,
const TrackTransformer trackTransformer 
)

Definition at line 93 of file CSCPairResidualsConstraint.cc.

References calculatePhi(), CSCDetId::chamber(), MuonSubdetId::CSC, CSCDetId, dphidzFromTrack(), CSCDetId::endcap(), TrackingRecHit::geographicalId(), isFiducial(), kModePhiPos, kModePhiy, kModePhiz, kModeRadius, m_averageRadius, CSCOverlapsAlignmentAlgorithm::m_combineME11, CSCOverlapsAlignmentAlgorithm::m_drdz, CSCOverlapsAlignmentAlgorithm::m_fiducial, CSCOverlapsAlignmentAlgorithm::m_hitsPerChamber, m_id_i, m_id_j, m_iZ, m_jZ, CSCOverlapsAlignmentAlgorithm::m_makeHistograms, CSCOverlapsAlignmentAlgorithm::m_maxdrdz, CSCOverlapsAlignmentAlgorithm::m_minHitsPerChamber, CSCOverlapsAlignmentAlgorithm::m_mode, CSCOverlapsAlignmentAlgorithm::m_occupancy, CSCOverlapsAlignmentAlgorithm::m_offsetResiduals, m_offsetResiduals, CSCOverlapsAlignmentAlgorithm::m_offsetResiduals_normalized, CSCOverlapsAlignmentAlgorithm::m_offsetResiduals_weighted, m_parent, m_radial, CSCOverlapsAlignmentAlgorithm::m_slope, CSCOverlapsAlignmentAlgorithm::m_slope_MEm1, CSCOverlapsAlignmentAlgorithm::m_slope_MEm2, CSCOverlapsAlignmentAlgorithm::m_slope_MEm3, CSCOverlapsAlignmentAlgorithm::m_slope_MEm4, CSCOverlapsAlignmentAlgorithm::m_slope_MEp1, CSCOverlapsAlignmentAlgorithm::m_slope_MEp2, CSCOverlapsAlignmentAlgorithm::m_slope_MEp3, CSCOverlapsAlignmentAlgorithm::m_slope_MEp4, CSCOverlapsAlignmentAlgorithm::m_slopeFromTrackRefit, CSCOverlapsAlignmentAlgorithm::m_slopeResiduals, m_slopeResiduals, CSCOverlapsAlignmentAlgorithm::m_slopeResiduals_normalized, CSCOverlapsAlignmentAlgorithm::m_slopeResiduals_weighted, m_sum1, m_sumN, m_sumx, m_sumxx, m_sumxy, m_sumy, m_sumyy, CSCOverlapsAlignmentAlgorithm::m_truncateOffsetResid, CSCOverlapsAlignmentAlgorithm::m_truncateSlopeResid, CSCOverlapsAlignmentAlgorithm::m_useHitWeights, CSCOverlapsAlignmentAlgorithm::m_useTrackWeights, m_Zplane, DetId::Muon, phi, funct::pow(), alignCSCRings::r, CSCDetId::ring(), mathSSE::sqrt(), CSCDetId::station(), CommonMethods::weight(), and z.

                                                                                                                                                                         {
  std::vector<const TransientTrackingRecHit*> hits_i;
  std::vector<const TransientTrackingRecHit*> hits_j;

  for (std::vector<TrajectoryMeasurement>::const_iterator measurement = measurements.begin();  measurement != measurements.end();  ++measurement) {
    const TransientTrackingRecHit *hit = &*(measurement->recHit());

    DetId id = hit->geographicalId();
    if (id.det() == DetId::Muon  &&  id.subdetId() == MuonSubdetId::CSC) {
      CSCDetId cscid(id.rawId());
      CSCDetId chamberId(cscid.endcap(), cscid.station(), cscid.ring(), cscid.chamber(), 0);
      if (m_parent->m_combineME11  &&  cscid.station() == 1  &&  cscid.ring() == 4) chamberId = CSCDetId(cscid.endcap(), 1, 1, cscid.chamber(), 0);

      if (chamberId == m_id_i) hits_i.push_back(hit);
      if (chamberId == m_id_j) hits_j.push_back(hit);
    }
  }

  if (m_parent->m_makeHistograms) {
    m_parent->m_hitsPerChamber->Fill(hits_i.size());
    m_parent->m_hitsPerChamber->Fill(hits_j.size());
  }

  // require minimum number of hits (if the requirement is too low (~2), some NANs might result...)
  if (int(hits_i.size()) < m_parent->m_minHitsPerChamber  ||  int(hits_j.size()) < m_parent->m_minHitsPerChamber) return false;

  // maybe require segments to be fiducial
  if (m_parent->m_fiducial  &&  !(isFiducial(hits_i, true)  &&  isFiducial(hits_j, false))) return false;

  double intercept_i = 0.;
  double interceptError2_i = 0.;
  double slope_i = 0.;
  double slopeError2_i = 0.;
  double intercept_j = 0.;
  double interceptError2_j = 0.;
  double slope_j = 0.;
  double slopeError2_j = 0.;

  // if slopeFromTrackRefit, then you'll need to refit the whole track without this station's hits;
  // need at least two other stations for that to be reliable
  if (m_parent->m_slopeFromTrackRefit) {
    double dphidz;
    if (dphidzFromTrack(measurements, track, trackTransformer, dphidz)) {
      double sum1_i = 0.;
      double sumy_i = 0.;
      for (std::vector<const TransientTrackingRecHit*>::const_iterator hit = hits_i.begin();  hit != hits_i.end();  ++hit) {
        double phi, phierr2;
        calculatePhi(*hit, phi, phierr2, false, true);
        double z = (*hit)->globalPosition().z() - m_Zplane;

        double weight = 1.;
        if (m_parent->m_useHitWeights) weight = 1./phierr2;
        sum1_i += weight;
        sumy_i += weight * (phi - z*dphidz);
      }

      double sum1_j = 0.;
      double sumy_j = 0.;
      for (std::vector<const TransientTrackingRecHit*>::const_iterator hit = hits_j.begin();  hit != hits_j.end();  ++hit) {
        double phi, phierr2;
        calculatePhi(*hit, phi, phierr2, false, true);
        double z = (*hit)->globalPosition().z() - m_Zplane;

        double weight = 1.;
        if (m_parent->m_useHitWeights) weight = 1./phierr2;
        sum1_j += weight;
        sumy_j += weight * (phi - z*dphidz);
      }

      if (sum1_i != 0.  &&  sum1_j != 0.) {
        slope_i = slope_j = dphidz;

        intercept_i = sumy_i / sum1_i;
        interceptError2_i = 1. / sum1_i;

        intercept_j = sumy_j / sum1_j;
        interceptError2_j = 1. / sum1_j;
      }
      else return false;
    }
  }

  else { // not slopeFromTrackRefit
    double sum1_i = 0.;
    double sumx_i = 0.;
    double sumy_i = 0.;
    double sumxx_i = 0.;
    double sumxy_i = 0.;
    for (std::vector<const TransientTrackingRecHit*>::const_iterator hit = hits_i.begin();  hit != hits_i.end();  ++hit) {
      double phi, phierr2;
      calculatePhi(*hit, phi, phierr2, false, true);
      double z = (*hit)->globalPosition().z() - m_Zplane;

      double weight = 1.;
      if (m_parent->m_useHitWeights) weight = 1./phierr2;
      sum1_i += weight;
      sumx_i += weight * z;
      sumy_i += weight * phi;
      sumxx_i += weight * z*z;
      sumxy_i += weight * z*phi;
    }

    double sum1_j = 0.;
    double sumx_j = 0.;
    double sumy_j = 0.;
    double sumxx_j = 0.;
    double sumxy_j = 0.;
    for (std::vector<const TransientTrackingRecHit*>::const_iterator hit = hits_j.begin();  hit != hits_j.end();  ++hit) {
      double phi, phierr2;
      calculatePhi(*hit, phi, phierr2, false, true);
      double z = (*hit)->globalPosition().z() - m_Zplane;
        
      double weight = 1.;
      if (m_parent->m_useHitWeights) weight = 1./phierr2;
      sum1_j += weight;
      sumx_j += weight * z;
      sumy_j += weight * phi;
      sumxx_j += weight * z*z;
      sumxy_j += weight * z*phi;
    }

    double delta_i = (sum1_i*sumxx_i) - (sumx_i*sumx_i);    
    double delta_j = (sum1_j*sumxx_j) - (sumx_j*sumx_j);    
    if (delta_i != 0.  &&  delta_j != 0.) {
      intercept_i = ((sumxx_i*sumy_i) - (sumx_i*sumxy_i))/delta_i;
      interceptError2_i = sumxx_i/delta_i;
      slope_i = ((sum1_i*sumxy_i) - (sumx_i*sumy_i))/delta_i;
      slopeError2_i = sum1_i/delta_i;

      intercept_j = ((sumxx_j*sumy_j) - (sumx_j*sumxy_j))/delta_j;
      interceptError2_j = sumxx_j/delta_j;
      slope_j = ((sum1_j*sumxy_j) - (sumx_j*sumy_j))/delta_j;
      slopeError2_j = sum1_j/delta_j;
    }
    else return false;
  }

  // from hits on the two chambers, determine radial_intercepts separately and radial_slope together
  double sum1_ri = 0.;
  double sumx_ri = 0.;
  double sumy_ri = 0.;
  double sumxx_ri = 0.;
  double sumxy_ri = 0.;
  for (std::vector<const TransientTrackingRecHit*>::const_iterator hit = hits_i.begin();  hit != hits_i.end();  ++hit) {
      double r = (*hit)->globalPosition().perp();
      double z = (*hit)->globalPosition().z() - m_Zplane;
      sum1_ri += 1.;
      sumx_ri += z;
      sumy_ri += r;
      sumxx_ri += z*z;
      sumxy_ri += z*r;
  }
  double radial_delta_i = (sum1_ri*sumxx_ri) - (sumx_ri*sumx_ri);
  if (radial_delta_i == 0.) return false;
  double radial_slope_i = ((sum1_ri*sumxy_ri) - (sumx_ri*sumy_ri))/radial_delta_i;
  double radial_intercept_i = ((sumxx_ri*sumy_ri) - (sumx_ri*sumxy_ri))/radial_delta_i + radial_slope_i*(m_iZ - m_Zplane);

  double sum1_rj = 0.;
  double sumx_rj = 0.;
  double sumy_rj = 0.;
  double sumxx_rj = 0.;
  double sumxy_rj = 0.;
  for (std::vector<const TransientTrackingRecHit*>::const_iterator hit = hits_j.begin();  hit != hits_j.end();  ++hit) {
      double r = (*hit)->globalPosition().perp();
      double z = (*hit)->globalPosition().z() - m_Zplane;
      sum1_rj += 1.;
      sumx_rj += z;
      sumy_rj += r;
      sumxx_rj += z*z;
      sumxy_rj += z*r;
  }
  double radial_delta_j = (sum1_rj*sumxx_rj) - (sumx_rj*sumx_rj);
  if (radial_delta_j == 0.) return false;
  double radial_slope_j = ((sum1_rj*sumxy_rj) - (sumx_rj*sumy_rj))/radial_delta_j;
  double radial_intercept_j = ((sumxx_rj*sumy_rj) - (sumx_rj*sumxy_rj))/radial_delta_j + radial_slope_j*(m_jZ - m_Zplane);

  double radial_delta = ((sum1_ri + sum1_rj)*(sumxx_ri + sumxx_rj)) - ((sumx_ri + sumx_rj)*(sumx_ri + sumx_rj));
  if (radial_delta == 0.) return false;
  double radial_intercept = (((sumxx_ri + sumxx_rj)*(sumy_ri + sumy_rj)) - ((sumx_ri + sumx_rj)*(sumxy_ri + sumxy_rj)))/radial_delta;
  double radial_slope = (((sum1_ri + sum1_rj)*(sumxy_ri + sumxy_rj)) - ((sumx_ri + sumx_rj)*(sumy_ri + sumy_rj)))/radial_delta;

  if (m_parent->m_makeHistograms) {
    m_parent->m_drdz->Fill(radial_slope);
  }
  if (m_parent->m_maxdrdz > 0.  &&  fabs(radial_slope) > m_parent->m_maxdrdz) return false;

  double quantity = 0.;
  double quantityError2 = 0.;
  if (m_parent->m_mode == kModePhiy) {  // phiy comes from track d(rphi)/dz
    quantity = (slope_i*radial_intercept_i) - (slope_j*radial_intercept_j);
    quantityError2 = (slopeError2_i)*pow(radial_intercept_i, 2) + (slopeError2_j)*pow(radial_intercept_j, 2);
  }
  else if (m_parent->m_mode == kModePhiPos  ||  m_parent->m_mode == kModeRadius) {  // phipos comes from phi intercepts
    quantity = intercept_i - intercept_j;
    quantityError2 = interceptError2_i + interceptError2_j;
  }
  else if (m_parent->m_mode == kModePhiz) {  // phiz comes from the slope of rphi intercepts
    quantity = (intercept_i - intercept_j) * radial_intercept;
    quantityError2 = (interceptError2_i + interceptError2_j) * pow(radial_intercept, 2);
  }
  else assert(false);

  if (quantityError2 == 0.) return false;

  double slopeResid = ((slope_i*radial_intercept_i) - (slope_j*radial_intercept_j)) * 1000.;
  double slopeResidError2 = ((slopeError2_i)*pow(radial_intercept_i, 2) + (slopeError2_j)*pow(radial_intercept_j, 2)) * 1000. * 1000.;
  double offsetResid = (intercept_i - intercept_j) * radial_intercept * 10.;
  double offsetResidError2 = (interceptError2_i + interceptError2_j) * pow(radial_intercept, 2) * 10. * 10.;

  if (m_parent->m_truncateSlopeResid > 0.  &&  fabs(slopeResid) > m_parent->m_truncateSlopeResid) return false;
  if (m_parent->m_truncateOffsetResid > 0.  &&  fabs(offsetResid) > m_parent->m_truncateOffsetResid) return false;

  double weight = 1.;
  if (m_parent->m_useTrackWeights) weight = 1./quantityError2;

  // fill the running sums for this CSCPairResidualsConstraint
  m_sumN += 1;
  m_sum1 += weight;
  m_sumx += weight * (radial_intercept - m_averageRadius);
  m_sumy += weight * quantity;
  m_sumxx += weight * pow(radial_intercept - m_averageRadius, 2);
  m_sumyy += weight * quantity*quantity;
  m_sumxy += weight * (radial_intercept - m_averageRadius)*quantity;

  if (m_parent->m_makeHistograms) {
    double rphi_slope_i = slope_i * radial_intercept_i;
    double rphi_slope_j = slope_j * radial_intercept_j;

    if (m_parent->m_slopeFromTrackRefit) {
      m_parent->m_slope->Fill(rphi_slope_i);  // == rphi_slope_j

      if (m_id_i.endcap() == 1  &&  m_id_i.station() == 4) m_parent->m_slope_MEp4->Fill(rphi_slope_i);
      if (m_id_i.endcap() == 1  &&  m_id_i.station() == 3) m_parent->m_slope_MEp3->Fill(rphi_slope_i);
      if (m_id_i.endcap() == 1  &&  m_id_i.station() == 2) m_parent->m_slope_MEp2->Fill(rphi_slope_i);
      if (m_id_i.endcap() == 1  &&  m_id_i.station() == 1) m_parent->m_slope_MEp1->Fill(rphi_slope_i);
      if (m_id_i.endcap() == 2  &&  m_id_i.station() == 1) m_parent->m_slope_MEm1->Fill(rphi_slope_i);
      if (m_id_i.endcap() == 2  &&  m_id_i.station() == 2) m_parent->m_slope_MEm2->Fill(rphi_slope_i);
      if (m_id_i.endcap() == 2  &&  m_id_i.station() == 3) m_parent->m_slope_MEm3->Fill(rphi_slope_i);
      if (m_id_i.endcap() == 2  &&  m_id_i.station() == 4) m_parent->m_slope_MEm4->Fill(rphi_slope_i);
    }
    else {
      m_parent->m_slope->Fill(rphi_slope_i); m_parent->m_slope->Fill(rphi_slope_j);

      if (m_id_i.endcap() == 1  &&  m_id_i.station() == 4) { m_parent->m_slope_MEp4->Fill(rphi_slope_i); m_parent->m_slope_MEp4->Fill(rphi_slope_j); }
      if (m_id_i.endcap() == 1  &&  m_id_i.station() == 3) { m_parent->m_slope_MEp3->Fill(rphi_slope_i); m_parent->m_slope_MEp3->Fill(rphi_slope_j); }
      if (m_id_i.endcap() == 1  &&  m_id_i.station() == 2) { m_parent->m_slope_MEp2->Fill(rphi_slope_i); m_parent->m_slope_MEp2->Fill(rphi_slope_j); }
      if (m_id_i.endcap() == 1  &&  m_id_i.station() == 1) { m_parent->m_slope_MEp1->Fill(rphi_slope_i); m_parent->m_slope_MEp1->Fill(rphi_slope_j); }
      if (m_id_i.endcap() == 2  &&  m_id_i.station() == 1) { m_parent->m_slope_MEm1->Fill(rphi_slope_i); m_parent->m_slope_MEm1->Fill(rphi_slope_j); }
      if (m_id_i.endcap() == 2  &&  m_id_i.station() == 2) { m_parent->m_slope_MEm2->Fill(rphi_slope_i); m_parent->m_slope_MEm2->Fill(rphi_slope_j); }
      if (m_id_i.endcap() == 2  &&  m_id_i.station() == 3) { m_parent->m_slope_MEm3->Fill(rphi_slope_i); m_parent->m_slope_MEm3->Fill(rphi_slope_j); }
      if (m_id_i.endcap() == 2  &&  m_id_i.station() == 4) { m_parent->m_slope_MEm4->Fill(rphi_slope_i); m_parent->m_slope_MEm4->Fill(rphi_slope_j); }
    }

    m_slopeResiduals->Fill(slopeResid);
    m_offsetResiduals->Fill(offsetResid);
    m_radial->Fill(radial_intercept);

    m_parent->m_slopeResiduals->Fill(slopeResid);
    m_parent->m_slopeResiduals_weighted->Fill(slopeResid, 1./slopeResidError2);
    m_parent->m_slopeResiduals_normalized->Fill(slopeResid/sqrt(slopeResidError2));

    m_parent->m_offsetResiduals->Fill(offsetResid);
    m_parent->m_offsetResiduals_weighted->Fill(offsetResid, 1./offsetResidError2);
    m_parent->m_offsetResiduals_normalized->Fill(offsetResid/sqrt(offsetResidError2));

    double ringbin = 0;
    if (m_id_i.endcap() == 2  &&  m_id_i.station() == 4  &&  m_id_i.ring() == 2) ringbin = 1.5;
    else if (m_id_i.endcap() == 2  &&  m_id_i.station() == 4  &&  m_id_i.ring() == 1) ringbin = 2.5;
    else if (m_id_i.endcap() == 2  &&  m_id_i.station() == 3  &&  m_id_i.ring() == 2) ringbin = 3.5;
    else if (m_id_i.endcap() == 2  &&  m_id_i.station() == 3  &&  m_id_i.ring() == 1) ringbin = 4.5;
    else if (m_id_i.endcap() == 2  &&  m_id_i.station() == 2  &&  m_id_i.ring() == 2) ringbin = 5.5;
    else if (m_id_i.endcap() == 2  &&  m_id_i.station() == 2  &&  m_id_i.ring() == 1) ringbin = 6.5;
    else if (m_id_i.endcap() == 2  &&  m_id_i.station() == 1  &&  m_id_i.ring() == 3) ringbin = 7.5;
    else if (m_id_i.endcap() == 2  &&  m_id_i.station() == 1  &&  m_id_i.ring() == 2) ringbin = 8.5;
    else if (m_id_i.endcap() == 2  &&  m_id_i.station() == 1  &&  m_id_i.ring() == 1) ringbin = 9.5;
    else if (m_id_i.endcap() == 2  &&  m_id_i.station() == 1  &&  m_id_i.ring() == 4) ringbin = 10.5;
    else if (m_id_i.endcap() == 1  &&  m_id_i.station() == 1  &&  m_id_i.ring() == 4) ringbin = 11.5;
    else if (m_id_i.endcap() == 1  &&  m_id_i.station() == 1  &&  m_id_i.ring() == 1) ringbin = 12.5;
    else if (m_id_i.endcap() == 1  &&  m_id_i.station() == 1  &&  m_id_i.ring() == 2) ringbin = 13.5;
    else if (m_id_i.endcap() == 1  &&  m_id_i.station() == 1  &&  m_id_i.ring() == 3) ringbin = 14.5;
    else if (m_id_i.endcap() == 1  &&  m_id_i.station() == 2  &&  m_id_i.ring() == 1) ringbin = 15.5;
    else if (m_id_i.endcap() == 1  &&  m_id_i.station() == 2  &&  m_id_i.ring() == 2) ringbin = 16.5;
    else if (m_id_i.endcap() == 1  &&  m_id_i.station() == 3  &&  m_id_i.ring() == 1) ringbin = 17.5;
    else if (m_id_i.endcap() == 1  &&  m_id_i.station() == 3  &&  m_id_i.ring() == 2) ringbin = 18.5;
    else if (m_id_i.endcap() == 1  &&  m_id_i.station() == 4  &&  m_id_i.ring() == 1) ringbin = 19.5;
    else if (m_id_i.endcap() == 1  &&  m_id_i.station() == 4  &&  m_id_i.ring() == 2) ringbin = 20.5;
    m_parent->m_occupancy->Fill(m_id_i.chamber() + 0.5, ringbin);
  }

  return true;
}
void CSCPairResidualsConstraint::calculatePhi ( const TransientTrackingRecHit hit,
double &  phi,
double &  phierr2,
bool  doRphi = false,
bool  globalPhi = false 
) [protected]

Definition at line 535 of file CSCPairResidualsConstraint.cc.

References angle(), funct::cos(), CSCDetId, CSCDetId::endcap(), TrackingRecHit::geographicalId(), CSCLayer::geometry(), TransientTrackingRecHit::globalPosition(), CSCGeometry::layer(), TrackingRecHit::localPosition(), TrackingRecHit::localPositionError(), m_cscGeometry, M_PI, CSCLayerGeometry::nearestStrip(), PV3DBase< T, PVType, FrameType >::perp(), PV3DBase< T, PVType, FrameType >::phi(), pos, dttmaxenums::R, alignCSCRings::r, CSCDetId::ring(), funct::sin(), CSCDetId::station(), strip(), CSCLayerGeometry::stripAngle(), PV3DBase< T, PVType, FrameType >::x(), LocalError::xx(), LocalError::xy(), create_public_lumi_plots::xy, PV3DBase< T, PVType, FrameType >::y(), and LocalError::yy().

Referenced by addTrack(), and isFiducial().

                                                                                                                                           {
  align::LocalPoint pos = hit->localPosition();
  DetId id = hit->geographicalId();
  CSCDetId cscid = CSCDetId(id.rawId());

  double r = 0.;
  if (globalPhi) {
    phi = hit->globalPosition().phi();
    r = hit->globalPosition().perp();

//     double sinAngle = sin(phi);
//     double cosAngle = cos(phi);
//     double xx = hit->globalPositionError().cxx();
//     double xy = hit->globalPositionError().cyx();
//     double yy = hit->globalPositionError().cyy();
//     phierr2 = (xx*cosAngle*cosAngle + 2.*xy*sinAngle*cosAngle + yy*sinAngle*sinAngle) / (r*r);
  }
  else {
    // these constants are related to the way CSC chambers are built--- really constant!
    const double R_ME11 = 181.5;
    const double R_ME12 = 369.7;
    const double R_ME21 = 242.7;
    const double R_ME31 = 252.7;
    const double R_ME41 = 262.65;
    const double R_MEx2 = 526.5;

    double R = 0.;
    if (cscid.station() == 1  &&  (cscid.ring() == 1  ||  cscid.ring() == 4)) R = R_ME11;
    else if (cscid.station() == 1  &&  cscid.ring() == 2) R = R_ME12;
    else if (cscid.station() == 2  &&  cscid.ring() == 1) R = R_ME21;
    else if (cscid.station() == 3  &&  cscid.ring() == 1) R = R_ME31;
    else if (cscid.station() == 4  &&  cscid.ring() == 1) R = R_ME41;
    else if (cscid.station() > 1  &&  cscid.ring() == 2) R = R_MEx2;
    else assert(false);
    r = (pos.y() + R);
  
    phi = atan2(pos.x(), r);

    if (cscid.endcap() == 1  &&  cscid.station() >= 3) phi *= -1;
    else if (cscid.endcap() == 2  &&  cscid.station() <= 2) phi *= -1;
  }

  int strip = m_cscGeometry->layer(id)->geometry()->nearestStrip(pos);
  double angle = m_cscGeometry->layer(id)->geometry()->stripAngle(strip) - M_PI/2.;
  double sinAngle = sin(angle);
  double cosAngle = cos(angle);
  double xx = hit->localPositionError().xx();
  double xy = hit->localPositionError().xy();
  double yy = hit->localPositionError().yy();
  phierr2 = (xx*cosAngle*cosAngle + 2.*xy*sinAngle*cosAngle + yy*sinAngle*sinAngle) / (r*r);

  if (doRphi) {
    phi *= r;
    phierr2 *= r*r;
  }
}
void CSCPairResidualsConstraint::configure ( CSCOverlapsAlignmentAlgorithm parent)

Definition at line 43 of file CSCPairResidualsConstraint.cc.

References m_id_i, m_id_j, m_identifier, CSCOverlapsAlignmentAlgorithm::m_makeHistograms, m_offsetResiduals, m_parent, m_radial, m_slopeResiduals, mergeVDriftHistosByStation::name, NULL, dbtoconf::parent, and indexGen::title.

                                                                                {
  m_parent = parent;

  if (m_parent->m_makeHistograms) {
    edm::Service<TFileService> tFileService;

    std::stringstream name, name2, name3, title;
    title << "i =" << m_id_i << " j =" << m_id_j;

    name << "slopeResiduals_" << m_identifier;
    m_slopeResiduals = tFileService->make<TH1F>(name.str().c_str(), title.str().c_str(), 300, -30., 30.);

    name2 << "offsetResiduals_" << m_identifier;
    m_offsetResiduals = tFileService->make<TH1F>(name2.str().c_str(), title.str().c_str(), 300, -30., 30.);

    name3 << "radial_" << m_identifier;
    m_radial = tFileService->make<TH1F>(name3.str().c_str(), title.str().c_str(), 700, 0., 700.);
  }
  else {
    m_slopeResiduals = NULL;
    m_offsetResiduals = NULL;
    m_radial = NULL;
  }
}
bool CSCPairResidualsConstraint::dphidzFromTrack ( const std::vector< TrajectoryMeasurement > &  measurements,
const reco::TransientTrack track,
const TrackTransformer trackTransformer,
double &  drphidz 
) [protected]

Definition at line 385 of file CSCPairResidualsConstraint.cc.

References angle(), CSCDetId::chamber(), TrajectoryStateCombiner::combine(), funct::cos(), MuonSubdetId::CSC, CSCDetId, CSCDetId::endcap(), TrajectoryStateOnSurface::globalDirection(), TrajectoryStateOnSurface::globalPosition(), TrajectoryStateOnSurface::isValid(), CSCOverlapsAlignmentAlgorithm::m_combineME11, m_id_i, m_id_j, CSCOverlapsAlignmentAlgorithm::m_minHitsPerChamber, CSCOverlapsAlignmentAlgorithm::m_minStationsInTrackRefits, m_parent, M_PI, m_propagator, m_Zplane, m_Zsurface, DetId::Muon, PV3DBase< T, PVType, FrameType >::perp(), PV3DBase< T, PVType, FrameType >::phi(), Propagator::propagate(), CSCDetId::ring(), funct::sin(), relativeConstraints::station, CSCDetId::station(), mergeVDriftHistosByStation::stations, pileupDistInMC::total, TrackTransformer::transform(), PV3DBase< T, PVType, FrameType >::x(), PV3DBase< T, PVType, FrameType >::y(), PV3DBase< T, PVType, FrameType >::z(), and z.

Referenced by addTrack().

                                                                                                                                                                                                {
  // make a list of hits on all chambers *other* than the ones associated with this constraint
  std::map<int,int> stations;
  int total = 0;
  TransientTrackingRecHit::ConstRecHitContainer cscHits;
  for (std::vector<TrajectoryMeasurement>::const_iterator measurement = measurements.begin();  measurement != measurements.end();  ++measurement) {
    DetId id = measurement->recHit()->geographicalId();
    if (id.det() == DetId::Muon  &&  id.subdetId() == MuonSubdetId::CSC) {
      CSCDetId cscid(id.rawId());
      CSCDetId chamberId(cscid.endcap(), cscid.station(), cscid.ring(), cscid.chamber(), 0);
      if (m_parent->m_combineME11  &&  cscid.station() == 1  &&  cscid.ring() == 4) chamberId = CSCDetId(cscid.endcap(), 1, 1, cscid.chamber(), 0);

      if (chamberId != m_id_i  &&  chamberId != m_id_j) {
        int station = (cscid.endcap() == 1 ? 1 : -1) * cscid.station();
        if (stations.find(station) == stations.end()) {
          stations[station] = 0;
        }
        stations[station]++;
        total++;

        cscHits.push_back(measurement->recHit());
      }
    }
  }

  // for the fit to be reliable, it needs to cross multiple stations
  int numStations = 0;
  for (std::map<int,int>::const_iterator station = stations.begin();  station != stations.end();  ++station) {
    if (station->second >= m_parent->m_minHitsPerChamber) {
      numStations++;
    }
  }

  if (numStations >= m_parent->m_minStationsInTrackRefits) {
    // refit the track with these hits
    std::vector<Trajectory> trajectories = trackTransformer->transform(track, cscHits);

    if (!trajectories.empty()) {
      const std::vector<TrajectoryMeasurement> &measurements2 = trajectories.begin()->measurements();

      // find the closest TSOS to the Z plane (on both sides)
      bool found_plus = false;
      bool found_minus = false;
      TrajectoryStateOnSurface tsos_plus, tsos_minus;
      for (std::vector<TrajectoryMeasurement>::const_iterator measurement = measurements2.begin();  measurement != measurements2.end();  ++measurement) {
        double z = measurement->recHit()->globalPosition().z();
        if (z > m_Zplane) {
          if (!found_plus  ||  fabs(z - m_Zplane) < fabs(tsos_plus.globalPosition().z() - m_Zplane)) {
            tsos_plus = TrajectoryStateCombiner().combine(measurement->forwardPredictedState(), measurement->backwardPredictedState());
          }
          if (tsos_plus.isValid()) found_plus = true;
        }
        else {
          if (!found_minus  ||  fabs(z - m_Zplane) < fabs(tsos_minus.globalPosition().z() - m_Zplane)) {
            tsos_minus = TrajectoryStateCombiner().combine(measurement->forwardPredictedState(), measurement->backwardPredictedState());
          }
          if (tsos_minus.isValid()) found_minus = true;
        }
      }

      // propagate from the closest TSOS to the Z plane (from both sides, if possible)
      TrajectoryStateOnSurface from_plus, from_minus;
      if (found_plus) {
        from_plus = m_propagator->propagate(tsos_plus, *m_Zsurface);
      }
      if (found_minus) {
        from_minus = m_propagator->propagate(tsos_minus, *m_Zsurface);
      }

      // if you have two sides, merge them
      TrajectoryStateOnSurface merged;
      if (found_plus  &&  from_plus.isValid()  &&  found_minus  &&  from_minus.isValid()) {
        merged = TrajectoryStateCombiner().combine(from_plus, from_minus);
      }
      else if (found_plus  &&  from_plus.isValid()) {
        merged = from_plus;
      }
      else if (found_minus  &&  from_minus.isValid()) {
        merged = from_minus;
      }
      else return false;

      // if, after all that, we have a good fit-and-propagation, report the direction
      if (merged.isValid()) {
        double angle = merged.globalPosition().phi() + M_PI/2.;
        GlobalVector direction = merged.globalDirection();
        double dxdz = direction.x() / direction.z();
        double dydz = direction.y() / direction.z();
        dphidz = (dxdz*cos(angle) + dydz*sin(angle)) / merged.globalPosition().perp();
        return true;
      }

    } // end if refit successful
  } // end if enough hits
  return false;
}
double CSCPairResidualsConstraint::error ( ) const [virtual]

Reimplemented from CSCPairConstraint.

Definition at line 21 of file CSCPairResidualsConstraint.cc.

References delta, kModePhiPos, kModePhiy, kModePhiz, kModeRadius, CSCOverlapsAlignmentAlgorithm::m_errorFromRMS, CSCOverlapsAlignmentAlgorithm::m_mode, m_parent, m_sum1, m_sumN, m_sumx, m_sumxx, m_sumy, m_sumyy, funct::pow(), and mathSSE::sqrt().

                                               {
  if (m_parent->m_errorFromRMS) {
    assert(m_sum1 > 0.);
    return sqrt((m_sumyy/m_sum1) - pow(m_sumy/m_sum1, 2))/sqrt(m_sumN);
  }
  else {
    double delta = (m_sum1*m_sumxx) - (m_sumx*m_sumx);
    assert(delta > 0.);
    if (m_parent->m_mode == kModePhiy  ||  m_parent->m_mode == kModePhiPos  ||  m_parent->m_mode == kModeRadius) {
      return sqrt(m_sumxx/delta);
    }
    else if (m_parent->m_mode == kModePhiz) {
      return sqrt(m_sum1/delta);
    }
    else assert(false);
  }
}
CSCDetId CSCPairResidualsConstraint::id_i ( ) const [inline]

Definition at line 46 of file CSCPairResidualsConstraint.h.

References m_id_i.

Referenced by CSCChamberFitter::radiusCorrection().

{ return m_id_i; };
CSCDetId CSCPairResidualsConstraint::id_j ( ) const [inline]

Definition at line 47 of file CSCPairResidualsConstraint.h.

References m_id_j.

{ return m_id_j; };
bool CSCPairResidualsConstraint::isFiducial ( std::vector< const TransientTrackingRecHit * > &  hits,
bool  is_i 
) [protected]

Definition at line 592 of file CSCPairResidualsConstraint.cc.

References calculatePhi(), delta, CSCGeometry::idToDet(), m_cscGeometry, CSCOverlapsAlignmentAlgorithm::m_fiducial_ME11, CSCOverlapsAlignmentAlgorithm::m_fiducial_ME12, CSCOverlapsAlignmentAlgorithm::m_fiducial_MEx1, CSCOverlapsAlignmentAlgorithm::m_fiducial_MEx2, m_id_i, m_id_j, m_iZ1, m_iZ6, m_jZ1, m_jZ6, CSCOverlapsAlignmentAlgorithm::m_makeHistograms, m_parent, CSCOverlapsAlignmentAlgorithm::m_useHitWeights, phi, CSCDetId::ring(), slope, mathSSE::sqrt(), CSCDetId::station(), GeomDet::surface(), toLocal(), CommonMethods::weight(), and z.

Referenced by addTrack().

                                                                                                      {
  // these constants are related to the way CSC chambers are built--- really constant!
  const double cut_ME11 = 0.086;
  const double cut_ME12 = 0.090;
  const double cut_MEx1 = 0.180;
  const double cut_MEx2 = 0.090;

  double sum1 = 0.;
  double sumx = 0.;
  double sumy = 0.;
  double sumxx = 0.;
  double sumxy = 0.;
  for (std::vector<const TransientTrackingRecHit*>::const_iterator hit = hits.begin();  hit != hits.end();  ++hit) {
    double phi, phierr2;
    calculatePhi(*hit, phi, phierr2);
    double z = (is_i ? m_cscGeometry->idToDet(m_id_i)->surface() : m_cscGeometry->idToDet(m_id_j)->surface()).toLocal((*hit)->globalPosition()).z();

    if (m_parent->m_makeHistograms) {
      if (m_id_i.station() == 1  &&  (m_id_i.ring() == 1  ||  m_id_i.ring() == 4)) {
        m_parent->m_fiducial_ME11->Fill(fabs(phi), sqrt(phierr2));
      }
      else if (m_id_i.station() == 1  &&  m_id_i.ring() == 2) {
        m_parent->m_fiducial_ME12->Fill(fabs(phi), sqrt(phierr2));
      }
      else if (m_id_i.station() > 1  &&  m_id_i.ring() == 1) {
        m_parent->m_fiducial_MEx1->Fill(fabs(phi), sqrt(phierr2));
      }
      else if (m_id_i.station() > 1  &&  m_id_i.ring() == 2) {
        m_parent->m_fiducial_MEx2->Fill(fabs(phi), sqrt(phierr2));
      }
    }
    
    double weight = 1.;
    if (m_parent->m_useHitWeights) weight = 1./phierr2;
    sum1 += weight;
    sumx += weight * z;
    sumy += weight * phi;
    sumxx += weight * z*z;
    sumxy += weight * z*phi;
  }
  double delta = (sum1*sumxx) - (sumx*sumx);
  if (delta == 0.) return false;
  double intercept = ((sumxx*sumy) - (sumx*sumxy))/delta;
  double slope = ((sum1*sumxy) - (sumx*sumy))/delta;

  double phi1 = intercept + slope*(is_i ? m_iZ1 : m_jZ1);
  double phi6 = intercept + slope*(is_i ? m_iZ6 : m_jZ6);

  if (m_id_i.station() == 1  &&  (m_id_i.ring() == 1  ||  m_id_i.ring() == 4)) {
    return (fabs(phi1) < cut_ME11  &&  fabs(phi6) < cut_ME11);
  }
  else if (m_id_i.station() == 1  &&  m_id_i.ring() == 2) {
    return (fabs(phi1) < cut_ME12  &&  fabs(phi6) < cut_ME12);
  }
  else if (m_id_i.station() > 1  &&  m_id_i.ring() == 1) {
    return (fabs(phi1) < cut_MEx1  &&  fabs(phi6) < cut_MEx1);
  }
  else if (m_id_i.station() > 1  &&  m_id_i.ring() == 2) {
    return (fabs(phi1) < cut_MEx2  &&  fabs(phi6) < cut_MEx2);
  }
  else assert(false);
}
double CSCPairResidualsConstraint::radius ( bool  is_i) const [inline]
void CSCPairResidualsConstraint::read ( std::vector< std::ifstream * > &  input,
std::vector< std::string > &  filenames 
)

Definition at line 488 of file CSCPairResidualsConstraint.cc.

References Exception, lut2db_cfg::filename, CSCPairConstraint::i(), CSCPairConstraint::j(), CSCPairConstraint::m_i, m_identifier, CSCPairConstraint::m_j, m_sum1, m_sumN, m_sumx, m_sumxx, m_sumxy, m_sumy, m_sumyy, mergeVDriftHistosByStation::name, and errorMatrix2Lands_multiChannel::sumN.

                                                                                                     {
  m_sumN = 0;
  m_sum1 = 0.;
  m_sumx = 0.;
  m_sumy = 0.;
  m_sumxx = 0.;
  m_sumyy = 0.;
  m_sumxy = 0.;

  std::vector<std::ifstream*>::const_iterator inputiter = input.begin();
  std::vector<std::string>::const_iterator filename = filenames.begin();
  for (;  inputiter != input.end();  ++inputiter, ++filename) {
    int linenumber = 0;
    bool touched = false;
    while (!(*inputiter)->eof()) {
      linenumber++;
      std::string name, eoln;
      unsigned int identifier;
      int i, j;
      int sumN;
      double sum1, sumx, sumy, sumxx, sumyy, sumxy;
    
      (**inputiter) >> name >> identifier >> i >> j >> sumN >> sum1 >> sumx >> sumy >> sumxx >> sumyy >> sumxy >> eoln;

      if (!(*inputiter)->eof()  &&  (name != "CSCPairResidualsConstraint"  ||  eoln != "EOLN")) throw cms::Exception("CorruptTempFile") << "Temporary file " << *filename << " is incorrectly formatted on line " << linenumber << std::endl;

      if (identifier == m_identifier) {
        if (i != m_i  ||  j != m_j) throw cms::Exception("CorruptTempFile") << "Wrong (i,j) for CSCPairResidualsConstraint " << m_identifier << " (" << m_i << "," << m_j << ") in file " << *filename << " on line " << linenumber << std::endl;
        touched = true;

        m_sumN += sumN;
        m_sum1 += sum1;
        m_sumx += sumx;
        m_sumy += sumy;
        m_sumxx += sumxx;
        m_sumyy += sumyy;
        m_sumxy += sumxy;
      }
    }

    (*inputiter)->clear();
    (*inputiter)->seekg(0, std::ios::beg);

    if (!touched) throw cms::Exception("CorruptTempFile") << "CSCPairResidualsConstraint " << m_identifier << " is missing from file " << *filename << std::endl;
  }
}
void CSCPairResidualsConstraint::setPropagator ( const Propagator propagator)
void CSCPairResidualsConstraint::setZplane ( const CSCGeometry cscGeometry)

Definition at line 68 of file CSCPairResidualsConstraint.cc.

References newFWLiteAna::build, CSCDetId::chamber(), CSCDetId::endcap(), CSCGeometry::idToDet(), m_averageRadius, m_cscGeometry, m_id_i, m_id_j, m_iZ, m_iZ1, m_iZ6, m_jZ, m_jZ1, m_jZ6, m_Zplane, m_Zsurface, GloballyPositioned< T >::position(), CSCDetId::ring(), CSCDetId::station(), GeomDet::surface(), GloballyPositioned< T >::toLocal(), and z.

bool CSCPairResidualsConstraint::valid ( ) const [virtual]
double CSCPairResidualsConstraint::value ( ) const [virtual]

Reimplemented from CSCPairConstraint.

Definition at line 9 of file CSCPairResidualsConstraint.cc.

References delta, kModePhiPos, kModePhiy, kModePhiz, kModeRadius, CSCOverlapsAlignmentAlgorithm::m_mode, m_parent, m_sum1, m_sumx, m_sumxx, m_sumxy, and m_sumy.

Referenced by CSCChamberFitter::radiusCorrection().

                                               {
  double delta = (m_sum1*m_sumxx) - (m_sumx*m_sumx);
  assert(delta > 0.);
  if (m_parent->m_mode == kModePhiy  ||  m_parent->m_mode == kModePhiPos  ||  m_parent->m_mode == kModeRadius) {
    return ((m_sumxx*m_sumy) - (m_sumx*m_sumxy))/delta;
  }
  else if (m_parent->m_mode == kModePhiz) {
    return ((m_sum1*m_sumxy) - (m_sumx*m_sumy))/delta;
  }
  else assert(false);
}
void CSCPairResidualsConstraint::write ( std::ofstream &  output)

Definition at line 482 of file CSCPairResidualsConstraint.cc.

References CSCPairConstraint::i(), CSCPairConstraint::j(), m_identifier, m_sum1, m_sumN, m_sumx, m_sumxx, m_sumxy, m_sumy, and m_sumyy.

                                                          {
  output << std::setprecision(14) << std::fixed;
  output << "CSCPairResidualsConstraint " << m_identifier << " " << i() << " " << j() << " "
         << m_sumN << " " << m_sum1 << " " << m_sumx << " " << m_sumy << " " << m_sumxx << " " << m_sumyy << " " << m_sumxy << " EOLN" << std::endl;
}

Member Data Documentation

Definition at line 71 of file CSCPairResidualsConstraint.h.

Referenced by addTrack(), and setZplane().

Definition at line 72 of file CSCPairResidualsConstraint.h.

Referenced by calculatePhi(), isFiducial(), radius(), and setZplane().

unsigned int CSCPairResidualsConstraint::m_identifier [protected]

Definition at line 64 of file CSCPairResidualsConstraint.h.

Referenced by configure(), read(), and write().

Definition at line 71 of file CSCPairResidualsConstraint.h.

Referenced by addTrack(), and setZplane().

Definition at line 71 of file CSCPairResidualsConstraint.h.

Referenced by isFiducial(), and setZplane().

Definition at line 71 of file CSCPairResidualsConstraint.h.

Referenced by isFiducial(), and setZplane().

Definition at line 71 of file CSCPairResidualsConstraint.h.

Referenced by addTrack(), and setZplane().

Definition at line 71 of file CSCPairResidualsConstraint.h.

Referenced by isFiducial(), and setZplane().

Definition at line 71 of file CSCPairResidualsConstraint.h.

Referenced by isFiducial(), and setZplane().

Definition at line 77 of file CSCPairResidualsConstraint.h.

Referenced by addTrack(), and configure().

Definition at line 73 of file CSCPairResidualsConstraint.h.

Referenced by dphidzFromTrack(), and setPropagator().

Definition at line 78 of file CSCPairResidualsConstraint.h.

Referenced by addTrack(), and configure().

Definition at line 76 of file CSCPairResidualsConstraint.h.

Referenced by addTrack(), and configure().

Definition at line 66 of file CSCPairResidualsConstraint.h.

Referenced by addTrack(), error(), read(), value(), and write().

Definition at line 67 of file CSCPairResidualsConstraint.h.

Referenced by addTrack(), error(), read(), valid(), and write().

Definition at line 66 of file CSCPairResidualsConstraint.h.

Referenced by addTrack(), error(), read(), value(), and write().

Definition at line 66 of file CSCPairResidualsConstraint.h.

Referenced by addTrack(), error(), read(), value(), and write().

Definition at line 66 of file CSCPairResidualsConstraint.h.

Referenced by addTrack(), read(), value(), and write().

Definition at line 66 of file CSCPairResidualsConstraint.h.

Referenced by addTrack(), error(), read(), value(), and write().

Definition at line 66 of file CSCPairResidualsConstraint.h.

Referenced by addTrack(), error(), read(), and write().

Definition at line 71 of file CSCPairResidualsConstraint.h.

Referenced by addTrack(), dphidzFromTrack(), and setZplane().

Definition at line 74 of file CSCPairResidualsConstraint.h.

Referenced by dphidzFromTrack(), and setZplane().