GEMCSCSegFit Class Reference

#include <GEMCSCSegFit.h>

Public Types
typedef ROOT::Math::SMatrix< double, 16, 4 >	SMatrix16by4
typedef ROOT::Math::SMatrix< double, 4 >	SMatrix4
typedef ROOT::Math::SMatrix< double, 16, 16, ROOT::Math::MatRepSym< double, 16 > >	SMatrixSym16
typedef ROOT::Math::SMatrix< double, 2, 2, ROOT::Math::MatRepSym< double, 2 > >	SMatrixSym2
typedef ROOT::Math::SMatrix< double, 4, 4, ROOT::Math::MatRepSym< double, 4 > >	SMatrixSym4
typedef ROOT::Math::SVector< double, 4 >	SVector4

Public Member Functions
double	chi2 (void) const
AlgebraicSymMatrix	covarianceMatrix (void)
const CSCChamber *	cscchamber (uint32_t id) const
const CSCLayer *	csclayer (uint32_t id) const
void	fit (void)
bool	fitdone () const
	GEMCSCSegFit (std::map< uint32_t, const CSCLayer * > csclayermap, std::map< uint32_t, const GEMEtaPartition * > gemrollmap, const std::vector< const TrackingRecHit * > hits)
const GEMEtaPartition *	gemetapartition (uint32_t id) const
std::vector< const TrackingRecHit * >	hits (void) const
LocalPoint	intercept () const
LocalVector	localdir () const
int	ndof (void) const
size_t	nhits (void) const
float	Rdev (float x, float y, float z) const
const CSCChamber *	refcscchamber () const
double	scaleXError (void) const
void	setScaleXError (double factor)
float	xdev (float x, float z) const
float	xfit (float z) const
float	ydev (float y, float z) const
float	yfit (float z) const
virtual	~GEMCSCSegFit ()

Protected Member Functions
SMatrix16by4	derivativeMatrix (void)
AlgebraicSymMatrix	flipErrors (const SMatrixSym4 &)
void	setOutFromIP (void)
SMatrixSym16	weightMatrix (void)

Protected Attributes
double	chi2_
std::map< uint32_t, const CSCLayer * >	csclayermap_
bool	fitdone_
std::map< uint32_t, const GEMEtaPartition * >	gemetapartmap_
std::vector< const TrackingRecHit * >	hits_
LocalPoint	intercept_
LocalVector	localdir_
int	ndof_
const CSCChamber *	refcscchamber_
uint32_t	refid_
double	scaleXError_
float	uslope_
float	vslope_

Private Member Functions
void	fit2 (void)
void	fitlsq (void)
void	setChi2 (void)

Detailed Description

Definition at line 47 of file GEMCSCSegFit.h.

Member Typedef Documentation

typedef ROOT::Math::SMatrix<double,16,4 > GEMCSCSegFit::SMatrix16by4

Definition at line 57 of file GEMCSCSegFit.h.

typedef ROOT::Math::SMatrix<double, 4 > GEMCSCSegFit::SMatrix4

Definition at line 60 of file GEMCSCSegFit.h.

typedef ROOT::Math::SMatrix<double,16,16,ROOT::Math::MatRepSym<double,16> > GEMCSCSegFit::SMatrixSym16

Definition at line 54 of file GEMCSCSegFit.h.

typedef ROOT::Math::SMatrix<double,2,2,ROOT::Math::MatRepSym<double,2> > GEMCSCSegFit::SMatrixSym2

Definition at line 64 of file GEMCSCSegFit.h.

typedef ROOT::Math::SMatrix<double,4,4,ROOT::Math::MatRepSym<double,4> > GEMCSCSegFit::SMatrixSym4

Definition at line 61 of file GEMCSCSegFit.h.

typedef ROOT::Math::SVector<double,4> GEMCSCSegFit::SVector4

Definition at line 67 of file GEMCSCSegFit.h.

Constructor & Destructor Documentation

GEMCSCSegFit::GEMCSCSegFit ( std::map< uint32_t, const CSCLayer * >  csclayermap, std::map< uint32_t, const GEMEtaPartition * >  gemrollmap, const std::vector< const TrackingRecHit * >  hits  )

inline

Definition at line 73 of file GEMCSCSegFit.h.

References csclayermap_, gemetapartmap_, and AlCaHLTBitMon_QueryRunRegistry::string.

                                                                                                                                                               : 
  csclayermap_( csclayermap ), gemetapartmap_( gemrollmap ), hits_( hits ), scaleXError_( 1.0 ), refid_( csclayermap_.begin()->first ), fitdone_( false ) 
    {
      // --- LogDebug info about reading of CSC Layer map and GEM Eta Partition map -----------------------
      edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::ctor] cached the csclayermap and the gemrollmap";

      // --- LogDebug for CSC Layer map -------------------------------------------------------------------
      std::stringstream csclayermapss; csclayermapss<<"[GEMCSCSegFit::ctor] :: csclayermap :: elements ["<<std::endl;
      for(std::map<uint32_t, const CSCLayer*>::const_iterator mapIt = csclayermap_.begin(); mapIt != csclayermap_.end(); ++mapIt)
    {
      csclayermapss<<"[CSC DetId "<<mapIt->first<<" ="<<CSCDetId(mapIt->first)<<", CSC Layer "<<mapIt->second<<" ="<<(mapIt->second)->id()<<"],"<<std::endl;
    }
      csclayermapss<<"]"<<std::endl;
      std::string csclayermapstr = csclayermapss.str();
      edm::LogVerbatim("GEMCSCSegFit") << csclayermapstr;
      // --- End LogDebug -----------------------------------------------------------------------------------

      // --- LogDebug for GEM Eta Partition map ------------------------------------------------------------
      std::stringstream gemetapartmapss; gemetapartmapss<<"[GEMCSCSegFit::ctor] :: gemetapartmap :: elements ["<<std::endl;
      for(std::map<uint32_t, const GEMEtaPartition*>::const_iterator mapIt = gemetapartmap_.begin(); mapIt != gemetapartmap_.end(); ++mapIt)
    {
      gemetapartmapss<<"[GEM DetId "<<mapIt->first<<" ="<<GEMDetId(mapIt->first)<<", GEM EtaPart "<<mapIt->second<<"],"<<std::endl;
    }
      gemetapartmapss<<"]"<<std::endl;
      std::string gemetapartmapstr = gemetapartmapss.str();
      edm::LogVerbatim("GEMCSCSegFit") << gemetapartmapstr;
      // --- End LogDebug -----------------------------------------------------------------------------------
    } 

virtual GEMCSCSegFit::~GEMCSCSegFit ( )

inlinevirtual

Definition at line 102 of file GEMCSCSegFit.h.

References covarianceMatrix(), and fit().

{}

Member Function Documentation

double GEMCSCSegFit::chi2 ( void  ) const

inline

Definition at line 126 of file GEMCSCSegFit.h.

References chi2_.

Referenced by GEMCSCSegAlgoRR::buildSegments().

{ return chi2_; }

AlgebraicSymMatrix GEMCSCSegFit::covarianceMatrix

(

void

)

Definition at line 525 of file GEMCSCSegFit.cc.

References patCaloMETCorrections_cff::A, derivativeMatrix(), flipErrors(), convertSQLiteXML::ok, mps_fire::result, weightMatrix(), and create_public_lumi_plots::weights.

Referenced by GEMCSCSegAlgoRR::buildSegments(), and ~GEMCSCSegFit().

                                                  {
  
  SMatrixSym16 weights = weightMatrix();
  SMatrix16by4 A = derivativeMatrix();
  edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::covarianceMatrix] weights matrix W: \n" << weights;      
  edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::covarianceMatrix] derivatives matrix A: \n" << A;      

  // (AT W A)^-1
  // e.g. See http://www.phys.ufl.edu/~avery/fitting.html, part I

  bool ok;
  SMatrixSym4 result =  ROOT::Math::SimilarityT(A, weights);
  edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::covarianceMatrix] (AT W A): \n" << result;      
  ok = result.Invert(); // inverts in place
  if ( !ok ) {
    edm::LogVerbatim("GEMCSCSegment|GEMCSCSegFit") << "[GEMCSCSegFit::calculateError] Failed to invert matrix: \n" << result;
    AlgebraicSymMatrix emptymatrix(4, 0. );
    return emptymatrix; // return empty matrix if matrix inversion failed
  }
  edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::covarianceMatrix] (AT W A)^-1: \n" << result;      
  
  // reorder components to match TrackingRecHit interface (GEMCSCSegment isa TrackingRecHit)
  // i.e. slopes first, then positions 
  AlgebraicSymMatrix flipped = flipErrors( result );
    
  return flipped;
}

const CSCChamber* GEMCSCSegFit::cscchamber ( uint32_t  id ) const

inline

Definition at line 131 of file GEMCSCSegFit.h.

References relativeConstraints::chamber, csclayermap_, and Exception.

Referenced by derivativeMatrix(), fit2(), fitlsq(), and setChi2().

                                                            {
    // Test whether id is found
    if(csclayermap_.find(id)==csclayermap_.end()) 
      { // id is not found
    throw cms::Exception("InvalidDetId") << "[GEMCSCSegFit] Failed to find CSCChamber in CSCLayerMap"<< std::endl; 
      } // chamber is not found and exception is thrown
    else 
      {  // id is found
    return (csclayermap_.find(id)->second)->chamber(); 
      } // chamber found and returned
  }

const CSCLayer* GEMCSCSegFit::csclayer ( uint32_t  id ) const

inline

Definition at line 142 of file GEMCSCSegFit.h.

References csclayermap_, and Exception.

                                                            {
    if(csclayermap_.find(id)==csclayermap_.end()) { 
      throw cms::Exception("InvalidDetId") << "[GEMCSCSegFit] Failed to find CSCLayer in CSCLayerMap" << std::endl;
    }
    else { return csclayermap_.find(id)->second; }
  }

GEMCSCSegFit::SMatrix16by4 GEMCSCSegFit::derivativeMatrix ( void  )

protected

Definition at line 469 of file GEMCSCSegFit.cc.

References MuonSubdetId::CSC, cscchamber(), edmIntegrityCheck::d, MuonSubdetId::GEM, gemetapartition(), runTauDisplay::gp, hits_, CSCChamber::layer(), TrackingRecHit::localPosition(), makeMuonMisalignmentScenario::matrix, TrackingRecHit::rawId(), refcscchamber(), DetId::subdetId(), GeomDet::toGlobal(), GeomDet::toLocal(), z, and PV3DBase< T, PVType, FrameType >::z().

Referenced by covarianceMatrix(), and fitdone().

                                                        {
  
  SMatrix16by4 matrix; // 16x4, init to 0
  int row = 0;
  
  for(std::vector<const TrackingRecHit*>::const_iterator it = hits_.begin(); it != hits_.end(); ++it) {
    
    const TrackingRecHit& hit = (**it);
    GlobalPoint gp;
    DetId d = DetId(hit.rawId());
    if(d.subdetId() == MuonSubdetId::GEM) {
      const GEMEtaPartition* roll = gemetapartition(GEMDetId(d));
      gp = roll->toGlobal(hit.localPosition());
    }
    else if(d.subdetId() == MuonSubdetId::CSC) {
      const CSCLayer* layer = cscchamber(CSCDetId(d))->layer(CSCDetId(d).layer());
      gp = layer->toGlobal(hit.localPosition());
    }
    else { edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit:fit2] - TrackingRecHit is not in GEM or CSC subdetector"; }
    LocalPoint lp = refcscchamber()->toLocal(gp);
    float z = lp.z();

    matrix(row, 0) = 1.;
    matrix(row, 2) = z;
    ++row;
    matrix(row, 1) = 1.;
    matrix(row, 3) = z;
    ++row;
  }
  return matrix;
}

void GEMCSCSegFit::fit

(

void

)

Definition at line 20 of file GEMCSCSegFit.cc.

References fit2(), fitdone(), fitlsq(), gen::n, and nhits().

Referenced by GEMCSCSegAlgoRR::buildSegments(), trackingPlots.Iteration::modules(), and ~GEMCSCSegFit().

                           {
  edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::fit] - start the fitting fun :: nhits = "<<nhits();
  if ( fitdone() ) return; // don't redo fit unnecessarily
  short n = nhits();
  switch ( n ) {
  case 1:
    edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::fit] - cannot fit just 1 hit!!";
    break;
  case 2:
    fit2();
    break;
  case 3:
  case 4:
  case 5:
  case 6:
  case 7:
  case 8:
    fitlsq();
    break;
  default:
    edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::fit] - cannot fit more than 8 hits!!";
  }  
}

void GEMCSCSegFit::fit2 ( void  )

private

Definition at line 44 of file GEMCSCSegFit.cc.

References chi2_, MuonSubdetId::CSC, cscchamber(), PVValHelper::dz, fitdone_, MuonSubdetId::GEM, gemetapartition(), hits_, intercept_, CSCChamber::layer(), CSCDetId::layer(), GEMDetId::layer(), TrackingRecHit::localPosition(), ndof_, refcscchamber(), setOutFromIP(), DetId::subdetId(), GeomDet::toGlobal(), GeomDet::toLocal(), uslope_, vslope_, PV3DBase< T, PVType, FrameType >::x(), PV3DBase< T, PVType, FrameType >::y(), and PV3DBase< T, PVType, FrameType >::z().

Referenced by fit(), and fitdone().

                            {

  edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::fit2] - start fit2()";
  // Just join the two points
  // Equation of straight line between (x1, y1) and (x2, y2) in xy-plane is
  //       y = mx + c
  // with m = (y2-y1)/(x2-x1)
  // and  c = (y1*x2-x2*y1)/(x2-x1)


  // 1) Check whether hits are on the same layer
  // -------------------------------------------
  std::vector<const TrackingRecHit*>::const_iterator ih = hits_.begin();
  // layer numbering: GEM: (1,2) CSC (3,4,5,6,7,8)
  int il1 = 0, il2 = 0;
  DetId d1 = DetId((*ih)->rawId());
  // check whether first hit is GEM or CSC
  if (d1.subdetId() == MuonSubdetId::GEM) {
    il1 = GEMDetId(d1).layer();
  }
  else if (d1.subdetId() == MuonSubdetId::CSC) {
    il1 = CSCDetId(d1).layer() + 2;
  }
  else { edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit:fit2] - TrackingRecHit is not in GEM or CSC subdetector"; }
  const TrackingRecHit& h1 = (**ih);
  ++ih;
  DetId d2 = DetId((*ih)->rawId());
  // check whether second hit is GEM or CSC
  if (d2.subdetId() == MuonSubdetId::GEM) {
    il2 = GEMDetId(d2).layer();
  }
  else if (d2.subdetId() == MuonSubdetId::CSC) {
    il2 = GEMDetId(d2).layer() + 2;
  }
  else { edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit:fit2] - TrackingRecHit is not in GEM or CSC subdetector"; }
  const TrackingRecHit& h2 = (**ih);
  // Skip if on same layer, but should be impossible :)
  if (il1 == il2) {
    edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit:fit2] - 2 hits on same layer!!";
    return;
  }


  // 2) Global Positions of hit 1 and 2 and
  //    Local  Positions of hit 1 and 2 w.r.t. reference CSC Chamber Frame 
  // ---------------------------------------------------------------------
  GlobalPoint h1glopos, h2glopos;
  // global position hit 1
  if(d1.subdetId() == MuonSubdetId::GEM) {
    const GEMEtaPartition* roll1 = gemetapartition(GEMDetId(d1));
    h1glopos = roll1->toGlobal(h1.localPosition());
  }
  else if(d1.subdetId() == MuonSubdetId::CSC) {
    const CSCLayer* layer1 = cscchamber(CSCDetId(d1))->layer(CSCDetId(d1).layer());
    h1glopos = layer1->toGlobal(h1.localPosition());
  }
  else { edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit:fit2] - TrackingRecHit is not in GEM or CSC subdetector"; }
  // global position hit 2
  if(d2.subdetId() == MuonSubdetId::GEM) {
    const GEMEtaPartition* roll2 = gemetapartition(GEMDetId(d2));
    h2glopos = roll2->toGlobal(h2.localPosition());
  }
  else if(d2.subdetId() == MuonSubdetId::CSC) {
    const CSCLayer* layer2 = cscchamber(CSCDetId(d2))->layer(CSCDetId(d2).layer());
    h2glopos = layer2->toGlobal(h2.localPosition());
  }
  else { edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit:fit2] - TrackingRecHit is not in GEM or CSC subdetector"; }
  // local positions hit 1 and 2 w.r.t. ref CSC Chamber Frame
  // We want hit wrt chamber (and local z will be != 0)
  LocalPoint h1pos = refcscchamber()->toLocal(h1glopos);  
  LocalPoint h2pos = refcscchamber()->toLocal(h2glopos);  


  // 3) Now make straight line between the two points in local coords
  // ----------------------------------------------------------------    
  float dz = h2pos.z()-h1pos.z();
  if(dz != 0) {
    uslope_ = ( h2pos.x() - h1pos.x() ) / dz ;
    vslope_ = ( h2pos.y() - h1pos.y() ) / dz ;
  }
  float uintercept = ( h1pos.x()*h2pos.z() - h2pos.x()*h1pos.z() ) / dz;
  float vintercept = ( h1pos.y()*h2pos.z() - h2pos.y()*h1pos.z() ) / dz;
  intercept_ = LocalPoint( uintercept, vintercept, 0.);

  setOutFromIP();

  //@@ NOT SURE WHAT IS SENSIBLE FOR THESE...
  chi2_ = 0.;
  ndof_ = 0;

  fitdone_ = true;
}

bool GEMCSCSegFit::fitdone ( ) const

inline

Definition at line 160 of file GEMCSCSegFit.h.

References derivativeMatrix(), fit2(), fitdone_, fitlsq(), flipErrors(), setChi2(), setOutFromIP(), and weightMatrix().

Referenced by fit().

{ return fitdone_; }

void GEMCSCSegFit::fitlsq ( void  )

private

Definition at line 138 of file GEMCSCSegFit.cc.

References TtFullHadDaughter::B, MuonSubdetId::CSC, cscchamber(), edmIntegrityCheck::d, fitdone_, MuonSubdetId::GEM, gemetapartition(), runTauDisplay::gp, hits_, CSCChamber::id(), intercept_, CSCChamber::layer(), TrackingRecHit::localPosition(), TrackingRecHit::localPositionError(), convertSQLiteXML::ok, AlCaHLTBitMon_ParallelJobs::p, DetId::rawId(), TrackingRecHit::rawId(), refcscchamber(), setChi2(), setOutFromIP(), AlCaHLTBitMon_QueryRunRegistry::string, DetId::subdetId(), GeomDet::toGlobal(), GeomDet::toLocal(), uslope_, findQualityFiles::v, vslope_, LocalError::xx(), LocalError::xy(), LocalError::yy(), and z.

Referenced by fit(), and fitdone().

                              {
  
  edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::fitlsq] - start fitlsq";
  // Linear least-squares fit to up to 6 CSC rechits, one per layer in a CSC
  // and up to 2 GEM rechits in a GEM superchamber
  // (we can later later on go up to 4 hits in case of an overlapping chamber)
  // (... and if there is an overlap in the GEM chambers, than maybe we also
  //  have an overlap in the CSC chambers... maybe we can also benefit there)

  // Comments below taken from CSCSegFit algorithm.
  // Comments adapted from original  CSCSegAlgoSK algorithm.
  
  // Fit to the local x, y rechit coordinates in z projection
  // The CSC & GEM strip measurement controls the precision of x
  // The CSC wire measurement & GEM eta-partition controls the precision of y. 
  // Typical precision CSC: u (strip, sigma~200um), v (wire, sigma~1cm)
  // Typical precision GEM: u (strip, sigma~250um), v (eta-part, sigma~10-20cm)
  
  // Set up the normal equations for the least-squares fit as a matrix equation
  
  // We have a vector of measurements m, which is a 2n x 1 dim matrix
  // The transpose mT is (u1, v1, u2, v2, ..., un, vn) where
  // ui is the strip-associated measurement and 
  // vi is the wire-associated measurement 
  // for a given rechit i.
  
  // The fit is to
  // u = u0 + uz * z
  // v = v0 + vz * z
  // where u0, uz, v0, vz are the parameters to be obtained from the fit.
  
  // These are contained in a vector p which is a 4x1 dim matrix, and
  // its transpose pT is (u0, v0, uz, vz). Note the ordering!
  
  // The covariance matrix for each pair of measurements is 2 x 2 and
  // the inverse of this is the error matrix E.
  // The error matrix for the whole set of n measurements is a diagonal
  // matrix with diagonal elements the individual 2 x 2 error matrices
  // (because the inverse of a diagonal matrix is a diagonal matrix
  // with each element the inverse of the original.)
  
  // In function 'weightMatrix()', the variable 'matrix' is filled with this
  // block-diagonal overall covariance matrix. Then 'matrix' is inverted to the 
  // block-diagonal error matrix, and returned.
  
  // Define the matrix A as
  //    1   0   z1  0
  //    0   1   0   z1
  //    1   0   z2  0
  //    0   1   0   z2
  //    ..  ..  ..  ..
  //    1   0   zn  0
  //    0   1   0   zn
  
  // This matrix A is set up and returned by function 'derivativeMatrix()'.
  
  // Then the normal equations are described by the matrix equation
  //
  //    (AT E A)p = (AT E)m
  //
  // where AT is the transpose of A.
  
  // Call the combined matrix on the LHS, M, and that on the RHS, B:
  //     M p = B
  
  // We solve this for the parameter vector, p.
  // The elements of M and B then involve sums over the hits
  
  // The covariance matrix of the parameters is obtained by 
  // (AT E A)^-1 calculated in 'covarianceMatrix()'.
  

  // NOTE
  // We need local position of a RecHit w.r.t. the CHAMBER
  // and the RecHit itself only knows its local position w.r.t.
  // the LAYER, so we must explicitly transform global position.
  

  SMatrix4 M; // 4x4, init to 0
  SVector4 B; // 4x1, init to 0; 

  std::vector<const TrackingRecHit*>::const_iterator ih = hits_.begin();

  // LogDebug :: Loop over the TrackingRecHits and print the GEM and CSC Hits  
  for (ih = hits_.begin(); ih != hits_.end(); ++ih) 
    {
      edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::fitlsq] - looping over TrackingRecHits";
      const TrackingRecHit& hit = (**ih);
      DetId d = DetId(hit.rawId());
      edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::fitlsq] - Tracking RecHit in detid ("<<d.rawId()<<")";
      if(d.subdetId() == MuonSubdetId::GEM) {
    edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::fitlsq] - Tracking RecHit is a GEM Hit in detid ("<<d.rawId()<<")";
    edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::fitlsq] - GEM DetId ("<<GEMDetId(d.rawId())<<")";
      }
      else if(d.subdetId() == MuonSubdetId::CSC) {
    edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::fitlsq] - Tracking RecHit is a CSC Hit in detid ("<<d.rawId()<<")";
    edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::fitlsq] - CSC DetId ("<<CSCDetId(d.rawId())<<")";
      }
      else { edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit:fit2] - TrackingRecHit is not in GEM or CSC subdetector"; }
    }

  // Loop over the TrackingRecHits and make small (2x2) matrices used to fill the blockdiagonal covariance matrix E^-1
  for (ih = hits_.begin(); ih != hits_.end(); ++ih) 
    {
      const TrackingRecHit& hit = (**ih);
      GlobalPoint gp;
      DetId d = DetId(hit.rawId());
      if(d.subdetId() == MuonSubdetId::GEM) 
    {
      const GEMEtaPartition* roll = gemetapartition(GEMDetId(d));
      gp = roll->toGlobal(hit.localPosition());
    }
      else if(d.subdetId() == MuonSubdetId::CSC) 
    {
      const CSCLayer* layer = cscchamber(CSCDetId(d))->layer(CSCDetId(d).layer());
      gp = layer->toGlobal(hit.localPosition());
    }
      else { edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit:fit2] - TrackingRecHit is not in GEM or CSC subdetector"; }
      LocalPoint lp = refcscchamber()->toLocal(gp); 

      // LogDebug
      std::stringstream lpss; lpss<<lp; std::string lps = lpss.str();
      std::stringstream gpss; gpss<<gp; std::string gps = gpss.str();
      edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::fitlsq] - Tracking RecHit global position "<<std::setw(30)<<gps<<" and local position "<<std::setw(30)<<lps
                       <<" wrt reference csc chamber "<<refcscchamber()->id().rawId()<<" = "<<refcscchamber()->id();
      
      // Local position of hit w.r.t. chamber
      double u = lp.x();
      double v = lp.y();
      double z = lp.z();
      
      // Covariance matrix of local errors 
      SMatrixSym2 IC; // 2x2, init to 0
      
      IC(0,0) = hit.localPositionError().xx();
      IC(1,1) = hit.localPositionError().yy();
      //@@ NOT SURE WHICH OFF-DIAGONAL ELEMENT MUST BE DEFINED BUT (1,0) WORKS
      //@@ (and SMatrix enforces symmetry)
      IC(1,0) = hit.localPositionError().xy();
      // IC(0,1) = IC(1,0);

      edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::fit] 2x2 covariance matrix for this Tracking RecHit :: [[" << IC(0,0) <<", "<< IC(0,1) <<"]["<< IC(1,0) <<","<<IC(1,1)<<"]]";
      
      // Invert covariance matrix (and trap if it fails!)
      bool ok = IC.Invert();
      if ( !ok ) 
    {
      edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::fit] Failed to invert covariance matrix: \n" << IC;      
      return; // MATRIX INVERSION FAILED ... QUIT VOID FUNCTION
    }

      // M = (AT E A)
      // B = (AT E m)
      // for now fill only with sum of blockdiagonal 
      // elements of (E^-1)_i = IC_i for hit i
      M(0,0) += IC(0,0);
      M(0,1) += IC(0,1);
      M(0,2) += IC(0,0) * z;
      M(0,3) += IC(0,1) * z;
      B(0)   += u * IC(0,0) + v * IC(0,1);
      
      M(1,0) += IC(1,0);
      M(1,1) += IC(1,1);
      M(1,2) += IC(1,0) * z;
      M(1,3) += IC(1,1) * z;
      B(1)   += u * IC(1,0) + v * IC(1,1);
      
      M(2,0) += IC(0,0) * z;
      M(2,1) += IC(0,1) * z;
      M(2,2) += IC(0,0) * z * z;
      M(2,3) += IC(0,1) * z * z;
      B(2)   += ( u * IC(0,0) + v * IC(0,1) ) * z;
      
      M(3,0) += IC(1,0) * z;
      M(3,1) += IC(1,1) * z;
      M(3,2) += IC(1,0) * z * z;
      M(3,3) += IC(1,1) * z * z;
      B(3)   += ( u * IC(1,0) + v * IC(1,1) ) * z;
      
    } // End Loop over the TrackingRecHits to make the block matrices to be filled in M and B
  
  SVector4 p;
  bool ok = M.Invert();
  if (!ok )
    {
      edm::LogVerbatim("GEMCSCSegment|GEMCSCSegFit") << "[GEMCSCSegFit::fit] Failed to invert matrix: \n" << M;
      return; // MATRIX INVERSION FAILED ... QUIT VOID FUNCTION 
    }
  else 
    {
      p = M * B;
    }

  edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::fit] p = " 
          << p(0) << ", " << p(1) << ", " << p(2) << ", " << p(3);
  
  // fill member variables  (note origin has local z = 0)
  //  intercept_
  intercept_ = LocalPoint(p(0), p(1), 0.);
  
  // localdir_ - set so segment points outwards from IP
  uslope_ = p(2);
  vslope_ = p(3);
  setOutFromIP();
  
  // calculate chi2 of fit
  setChi2( );

  // flag fit has been done
  fitdone_ = true;

}

AlgebraicSymMatrix GEMCSCSegFit::flipErrors ( const SMatrixSym4 &  a )

protected

Definition at line 554 of file GEMCSCSegFit.cc.

References a, and mps_fire::i.

Referenced by covarianceMatrix(), and fitdone().

                                                                  { 
    
  // The GEMCSCSegment needs the error matrix re-arranged to match
  // parameters in order (uz, vz, u0, v0) 
  // where uz, vz = slopes, u0, v0 = intercepts
    
  edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::flipErrors] input: \n" << a;      

  AlgebraicSymMatrix hold(4, 0. ); 
      
  for ( short j=0; j!=4; ++j) {
    for (short i=0; i!=4; ++i) {
      hold(i+1,j+1) = a(i,j); // SMatrix counts from 0, AlgebraicMatrix from 1
    }
  }

  //  LogTrace("GEMCSCSegFit") << "[GEMCSCSegFit::flipErrors] after copy:";
  //  LogTrace("GEMCSCSegFit") << "(" << hold(1,1) << "  " << hold(1,2) << "  " << hold(1,3) << "  " << hold(1,4);
  //  LogTrace("GEMCSCSegFit") << " " << hold(2,1) << "  " << hold(2,2) << "  " << hold(2,3) << "  " << hold(2,4);
  //  LogTrace("GEMCSCSegFit") << " " << hold(3,1) << "  " << hold(3,2) << "  " << hold(3,3) << "  " << hold(3,4);
  //  LogTrace("GEMCSCSegFit") << " " << hold(4,1) << "  " << hold(4,2) << "  " << hold(4,3) << "  " << hold(4,4) << ")";

  // errors on slopes into upper left 
  hold(1,1) = a(2,2); 
  hold(1,2) = a(2,3); 
  hold(2,1) = a(3,2); 
  hold(2,2) = a(3,3); 
    
  // errors on positions into lower right 
  hold(3,3) = a(0,0); 
  hold(3,4) = a(0,1); 
  hold(4,3) = a(1,0); 
  hold(4,4) = a(1,1); 
    
  // must also interchange off-diagonal elements of off-diagonal 2x2 submatrices
  hold(4,1) = a(1,2);
  hold(3,2) = a(0,3);
  hold(2,3) = a(3,0); // = a(0,3)
  hold(1,4) = a(2,1); // = a(1,2)

  //  LogTrace("GEMCSCSegFit") << "[GEMCSCSegFit::flipErrors] after flip:";
  //  LogTrace("GEMCSCSegFit") << "(" << hold(1,1) << "  " << hold(1,2) << "  " << hold(1,3) << "  " << hold(1,4);
  //  LogTrace("GEMCSCSegFit") << " " << hold(2,1) << "  " << hold(2,2) << "  " << hold(2,3) << "  " << hold(2,4);
  //  LogTrace("GEMCSCSegFit") << " " << hold(3,1) << "  " << hold(3,2) << "  " << hold(3,3) << "  " << hold(3,4);
  //  LogTrace("GEMCSCSegFit") << " " << hold(4,1) << "  " << hold(4,2) << "  " << hold(4,3) << "  " << hold(4,4) << ")";

  return hold;
}

const GEMEtaPartition* GEMCSCSegFit::gemetapartition ( uint32_t  id ) const

inline

Definition at line 148 of file GEMCSCSegFit.h.

References Exception, and gemetapartmap_.

Referenced by derivativeMatrix(), fit2(), fitlsq(), and setChi2().

                                                            { 
    if(gemetapartmap_.find(id)==gemetapartmap_.end()) { 
      throw cms::Exception("InvalidDetId") << "[GEMCSCSegFit] Failed to find GEMEtaPartition in GEMEtaPartMap" << std::endl;
    }
    else { return gemetapartmap_.find(id)->second; }
  }

std::vector<const TrackingRecHit*> GEMCSCSegFit::hits ( void  ) const

inline

Definition at line 123 of file GEMCSCSegFit.h.

References hits_.

Referenced by ntupleDataFormat._TrackingParticleMatchAdaptor::bestMatchingTrackingParticle().

{ return hits_; }

LocalPoint GEMCSCSegFit::intercept ( ) const

inline

Definition at line 128 of file GEMCSCSegFit.h.

References intercept_.

Referenced by GEMCSCSegAlgoRR::buildSegments().

{ return intercept_;}

LocalVector GEMCSCSegFit::localdir ( ) const

inline

Definition at line 129 of file GEMCSCSegFit.h.

References localdir_.

Referenced by GEMCSCSegAlgoRR::buildSegments().

{ return localdir_;}

int GEMCSCSegFit::ndof ( void  ) const

inline

Definition at line 127 of file GEMCSCSegFit.h.

References ndof_.

{ return ndof_; }

size_t GEMCSCSegFit::nhits ( void  ) const

inline

Definition at line 125 of file GEMCSCSegFit.h.

References hits_.

Referenced by fit().

{ return hits_.size(); }

float GEMCSCSegFit::Rdev	(	float	x,
		float	y,
		float	z
	)		const

Definition at line 621 of file GEMCSCSegFit.cc.

References mathSSE::sqrt(), xdev(), and ydev().

Referenced by setScaleXError().

                                                        {
  return sqrt ( xdev(x,z)*xdev(x,z) + ydev(y,z)*ydev(y,z) );
}

const CSCChamber* GEMCSCSegFit::refcscchamber ( ) const

inline

Definition at line 154 of file GEMCSCSegFit.h.

References relativeConstraints::chamber, csclayermap_, Exception, and refid_.

Referenced by derivativeMatrix(), fit2(), fitlsq(), setChi2(), and setOutFromIP().

                                                            { 
    if(csclayermap_.find(refid_)==csclayermap_.end()) { 
      throw cms::Exception("InvalidDetId") << "[GEMCSCSegFit] Failed to find Reference CSCChamber in CSCLayerMap" << std::endl;
    }
    else { return (csclayermap_.find(refid_)->second)->chamber(); }
  }

double GEMCSCSegFit::scaleXError ( void  ) const

inline

Definition at line 124 of file GEMCSCSegFit.h.

References scaleXError_.

Referenced by weightMatrix().

{ return scaleXError_; }

void GEMCSCSegFit::setChi2 ( void  )

private

Definition at line 353 of file GEMCSCSegFit.cc.

References chi2_, MuonSubdetId::CSC, cscchamber(), edmIntegrityCheck::d, MuonSubdetId::GEM, gemetapartition(), runTauDisplay::gp, hits_, CSCChamber::id(), intercept_, CSCChamber::layer(), TrackingRecHit::localPosition(), TrackingRecHit::localPositionError(), ndof_, convertSQLiteXML::ok, DetId::rawId(), TrackingRecHit::rawId(), refcscchamber(), AlCaHLTBitMon_QueryRunRegistry::string, DetId::subdetId(), GeomDet::toGlobal(), GeomDet::toLocal(), uslope_, findQualityFiles::v, vslope_, PV3DBase< T, PVType, FrameType >::x(), LocalError::xx(), LocalError::xy(), PV3DBase< T, PVType, FrameType >::y(), LocalError::yy(), and z.

Referenced by fitdone(), and fitlsq().

                               {
  
  double chsq = 0.;
  bool gem = false;

  std::vector<const TrackingRecHit*>::const_iterator ih;
  for (ih = hits_.begin(); ih != hits_.end(); ++ih) {

    const TrackingRecHit& hit = (**ih);
    GlobalPoint gp;
    DetId d = DetId(hit.rawId());
    if(d.subdetId() == MuonSubdetId::GEM) {
      const GEMEtaPartition* roll = gemetapartition(GEMDetId(d));
      gp = roll->toGlobal(hit.localPosition());
      gem = true;
    }
    else if(d.subdetId() == MuonSubdetId::CSC) {
      const CSCLayer* layer = cscchamber(CSCDetId(d))->layer(CSCDetId(d).layer());
      gp = layer->toGlobal(hit.localPosition());
      gem = false;
    }
    else { edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit:fit2] - TrackingRecHit is not in GEM or CSC subdetector"; }
    LocalPoint lp = refcscchamber()->toLocal(gp);

    // LogDebug
    std::stringstream lpss; lpss<<lp; std::string lps = lpss.str();
    std::stringstream gpss; gpss<<gp; std::string gps = gpss.str();
    edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::setChi2] - Tracking RecHit in "<<(gem? "GEM":"CSC")<<" global position "<<std::setw(30)<<gps<<" and local position "<<std::setw(30)<<lps
                       <<" wrt reference csc chamber "<<refcscchamber()->id().rawId()<<" = "<<refcscchamber()->id();
    
    double u = lp.x();
    double v = lp.y();
    double z = lp.z();
    
    double du = intercept_.x() + uslope_ * z - u;
    double dv = intercept_.y() + vslope_ * z - v;
    
    edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::setChi2] u, v, z = " << u << ", " << v << ", " << z;

    SMatrixSym2 IC; // 2x2, init to 0

    IC(0,0) = hit.localPositionError().xx();
    //    IC(0,1) = hit.localPositionError().xy();
    IC(1,0) = hit.localPositionError().xy();
    IC(1,1) = hit.localPositionError().yy();
    //    IC(1,0) = IC(0,1);

    edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::setChi2] IC before = \n" << IC;

    // Invert covariance matrix
    bool ok = IC.Invert();
    if (!ok ){
      edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::setChi2] Failed to invert covariance matrix: \n" << IC;
      return; // MATRIX INVERSION FAILED ... QUIT VOID FUNCTION
    }
    edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::setChi2] IC after = \n" << IC;
    chsq += du*du*IC(0,0) + 2.*du*dv*IC(0,1) + dv*dv*IC(1,1);
    // LogDebug
    edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::setChi2] Contribution of this Tracking RecHit to Chi2: du^2*D(1,1) + 2*du*dv*D(1,2) + dv^2*D(2,2) = " 
                       << du*du <<"*"<<IC(0,0)<<" + 2.*"<<du<<"*"<<dv<<"*"<<IC(0,1)<<" + "<<dv*dv<<"*"<<IC(1,1)<<" = "<<du*du*IC(0,0) + 2.*du*dv*IC(0,1) + dv*dv*IC(1,1);
  }
  // LogDebug
  edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::setChi2] Total Chi2 = "<<chsq;
  edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::setChi2] Total NDof = "<<2.*hits_.size() - 4;
  edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::setChi2] Total Chi2/NDof = "<<((hits_.size()>2)?(chsq/(2.*hits_.size() - 4)):(0.0));

  // fill member variables
  chi2_ = chsq;
  ndof_ = 2.*hits_.size() - 4;

  edm::LogVerbatim("GEMCSCSegFit") << "[GEMCSCSegFit::setChi2] chi2 = " << chi2_ << "/" << ndof_ << " dof";

}

void GEMCSCSegFit::setOutFromIP ( void  )

protected

Definition at line 502 of file GEMCSCSegFit.cc.

References PVValHelper::dx, BeamSpotFakeParameters_cfi::dxdz, PVValHelper::dy, BeamSpotFakeParameters_cfi::dydz, PVValHelper::dz, intercept_, localdir_, refcscchamber(), mathSSE::sqrt(), GeomDet::toGlobal(), csvLumiCalc::unit, uslope_, vslope_, and z.

Referenced by fit2(), fitdone(), and fitlsq().

                                {
  // Set direction of segment to point from IP outwards
  // (Incorrect for particles not coming from IP, of course.)
  
  double dxdz = uslope_;
  double dydz = vslope_;
  double dz   = 1./sqrt(1. + dxdz*dxdz + dydz*dydz);
  double dx   = dz*dxdz;
  double dy   = dz*dydz;
  LocalVector localDir(dx,dy,dz);

  // localDir sometimes needs a sign flip 
  // Examine its direction and origin in global z: to point outward
  // the localDir should always have same sign as global z...
  
  double globalZpos    = ( refcscchamber()->toGlobal( intercept_ ) ).z();
  double globalZdir    = ( refcscchamber()->toGlobal( localDir  ) ).z();
  double directionSign = globalZpos * globalZdir;
  localdir_ = (directionSign * localDir ).unit();
}

void GEMCSCSegFit::setScaleXError ( double  factor )

inline

Definition at line 111 of file GEMCSCSegFit.h.

References Rdev(), scaleXError_, x, xdev(), xfit(), y, ydev(), yfit(), and z.

{ scaleXError_ = factor; }

GEMCSCSegFit::SMatrixSym16 GEMCSCSegFit::weightMatrix ( void  )

protected

Definition at line 430 of file GEMCSCSegFit.cc.

References hits_, TrackingRecHit::localPositionError(), makeMuonMisalignmentScenario::matrix, convertSQLiteXML::ok, scaleXError(), LocalError::xx(), LocalError::xy(), and LocalError::yy().

Referenced by covarianceMatrix(), and fitdone().

                                                    {
  
  bool ok = true;

  SMatrixSym16 matrix = ROOT::Math::SMatrixIdentity(); 
  // for CSC segment ::     max 6 rechits => 12x12, 
  // for GEM-CSC segment :: max 8 rechits => 16x16
  // for all :: init to 1's on diag

  int row = 0;
  
  for (std::vector<const TrackingRecHit*>::const_iterator it = hits_.begin(); it != hits_.end(); ++it) 
    {
   
      const TrackingRecHit& hit = (**it);

      // Note scaleXError allows rescaling the x error if necessary

      matrix(row, row)   = scaleXError()*hit.localPositionError().xx();
      matrix(row, row+1) = hit.localPositionError().xy();
      ++row;
      matrix(row, row-1) = hit.localPositionError().xy();
      matrix(row, row)   = hit.localPositionError().yy();
      ++row;
    }

  ok = matrix.Invert(); // invert in place
  if ( !ok ) 
    {
      edm::LogVerbatim("GEMCSCSegment|GEMCSCSegFit") << "[GEMCSCSegFit::weightMatrix] Failed to invert matrix: \n" << matrix;      
      SMatrixSym16 emptymatrix = ROOT::Math::SMatrixIdentity();
      return emptymatrix; // return (empty) identity matrix if matrix inversion failed 
    }
  return matrix;
}

float GEMCSCSegFit::xdev	(	float	x,
		float	z
	)		const

Definition at line 613 of file GEMCSCSegFit.cc.

References intercept_, uslope_, x, and PV3DBase< T, PVType, FrameType >::x().

Referenced by Rdev(), and setScaleXError().

                                                 {
  return intercept_.x() + uslope_ * z - x;
}

float GEMCSCSegFit::xfit

(

float

z

)

const

Definition at line 603 of file GEMCSCSegFit.cc.

References intercept_, uslope_, PV3DBase< T, PVType, FrameType >::x(), and z.

Referenced by setScaleXError().

                                        {
  //@@ ADD THIS TO EACH ACCESSOR OF FIT RESULTS?
  //  if ( !fitdone() ) fit();
  return intercept_.x() + uslope_ * z;
}

float GEMCSCSegFit::ydev	(	float	y,
		float	z
	)		const

Definition at line 617 of file GEMCSCSegFit.cc.

References intercept_, vslope_, y, and PV3DBase< T, PVType, FrameType >::y().

Referenced by Rdev(), and setScaleXError().

                                                 {
  return intercept_.y() + vslope_ * z - y;
}

float GEMCSCSegFit::yfit

(

float

z

)

const

Definition at line 609 of file GEMCSCSegFit.cc.

References intercept_, vslope_, PV3DBase< T, PVType, FrameType >::y(), and z.

Referenced by setScaleXError().

                                        {
  return intercept_.y() + vslope_ * z;
}

Member Data Documentation

double GEMCSCSegFit::chi2_

protected

Definition at line 194 of file GEMCSCSegFit.h.

Referenced by chi2(), fit2(), and setChi2().

std::map<uint32_t, const CSCLayer*> GEMCSCSegFit::csclayermap_

protected

Definition at line 184 of file GEMCSCSegFit.h.

Referenced by cscchamber(), csclayer(), GEMCSCSegFit(), and refcscchamber().

bool GEMCSCSegFit::fitdone_

protected

Definition at line 198 of file GEMCSCSegFit.h.

Referenced by fit2(), fitdone(), and fitlsq().

std::map<uint32_t, const GEMEtaPartition*> GEMCSCSegFit::gemetapartmap_

protected

Definition at line 185 of file GEMCSCSegFit.h.

Referenced by GEMCSCSegFit(), and gemetapartition().

std::vector<const TrackingRecHit*> GEMCSCSegFit::hits_

protected

Definition at line 189 of file GEMCSCSegFit.h.

Referenced by derivativeMatrix(), fit2(), fitlsq(), hits(), nhits(), setChi2(), and weightMatrix().

LocalPoint GEMCSCSegFit::intercept_

protected

Definition at line 192 of file GEMCSCSegFit.h.

Referenced by fit2(), fitlsq(), intercept(), setChi2(), setOutFromIP(), xdev(), xfit(), ydev(), and yfit().

LocalVector GEMCSCSegFit::localdir_

protected

Definition at line 193 of file GEMCSCSegFit.h.

Referenced by localdir(), and setOutFromIP().

int GEMCSCSegFit::ndof_

protected

Definition at line 195 of file GEMCSCSegFit.h.

Referenced by fit2(), ndof(), and setChi2().

const CSCChamber* GEMCSCSegFit::refcscchamber_

protected

Definition at line 186 of file GEMCSCSegFit.h.

uint32_t GEMCSCSegFit::refid_

protected

Definition at line 197 of file GEMCSCSegFit.h.

Referenced by refcscchamber().

double GEMCSCSegFit::scaleXError_

protected

Definition at line 196 of file GEMCSCSegFit.h.

Referenced by scaleXError(), and setScaleXError().

float GEMCSCSegFit::uslope_

protected

Definition at line 190 of file GEMCSCSegFit.h.

Referenced by fit2(), fitlsq(), setChi2(), setOutFromIP(), xdev(), and xfit().

float GEMCSCSegFit::vslope_

protected

Definition at line 191 of file GEMCSCSegFit.h.

Referenced by fit2(), fitlsq(), setChi2(), setOutFromIP(), ydev(), and yfit().