MuonSegFit Class Reference

#include <MuonSegFit.h>

Public Types
typedef std::vector< MuonRecHitPtr >	MuonRecHitContainer
typedef std::shared_ptr< TrackingRecHit >	MuonRecHitPtr
typedef ROOT::Math::SMatrix< double, MaxHits2, 4 >	SMatrix12by4
typedef ROOT::Math::SMatrix< double, 4 >	SMatrix4
typedef ROOT::Math::SMatrix< double, MaxHits2, MaxHits2, ROOT::Math::MatRepSym< double, MaxHits2 > >	SMatrixSym12
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)
bool	fit (void)
bool	fitdone () const
MuonRecHitContainer	hits (void) const
LocalPoint	intercept () const
LocalVector	localdir () const
	MuonSegFit (MuonRecHitContainer hits)
int	ndof (void) const
size_t	nhits (void) const
float	Rdev (float x, float y, float z) 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	~MuonSegFit ()

Static Public Attributes
static const int	MaxHits2 = 22

Protected Member Functions
SMatrix12by4	derivativeMatrix (void)
AlgebraicSymMatrix	flipErrors (const SMatrixSym4 &)
void	setOutFromIP (void)
SMatrixSym12	weightMatrix (void)

Protected Attributes
double	chi2_
bool	fitdone_
MuonRecHitContainer	hits_
LocalPoint	intercept_
LocalVector	localdir_
int	ndof_
double	scaleXError_
float	uslope_
float	vslope_

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

Detailed Description

Definition at line 35 of file MuonSegFit.h.

Member Typedef Documentation

typedef std::vector<MuonRecHitPtr> MuonSegFit::MuonRecHitContainer

Definition at line 42 of file MuonSegFit.h.

typedef std::shared_ptr<TrackingRecHit> MuonSegFit::MuonRecHitPtr

Definition at line 41 of file MuonSegFit.h.

typedef ROOT::Math::SMatrix<double,MaxHits2,4 > MuonSegFit::SMatrix12by4

Definition at line 49 of file MuonSegFit.h.

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

Definition at line 52 of file MuonSegFit.h.

typedef ROOT::Math::SMatrix<double,MaxHits2,MaxHits2,ROOT::Math::MatRepSym<double,MaxHits2> > MuonSegFit::SMatrixSym12

Definition at line 46 of file MuonSegFit.h.

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

Definition at line 56 of file MuonSegFit.h.

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

Definition at line 53 of file MuonSegFit.h.

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

Definition at line 59 of file MuonSegFit.h.

Constructor & Destructor Documentation

MuonSegFit::MuonSegFit ( MuonRecHitContainer  hits )

inline

Definition at line 66 of file MuonSegFit.h.

                                      : hits_( hits ), uslope_(.0), vslope_(.0), 
    chi2_(.0), ndof_(0), scaleXError_( 1.0 ), fitdone_( false ) {}

virtual MuonSegFit::~MuonSegFit ( )

inlinevirtual

Definition at line 69 of file MuonSegFit.h.

References covarianceMatrix(), and fit().

{}

Member Function Documentation

double MuonSegFit::chi2 ( void  ) const

inline

Definition at line 93 of file MuonSegFit.h.

References chi2_.

{ return chi2_; }

AlgebraicSymMatrix MuonSegFit::covarianceMatrix

(

void

)

Definition at line 364 of file MuonSegFit.cc.

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

Referenced by ~MuonSegFit().

                                                {
  
  SMatrixSym12 weights = weightMatrix();
  SMatrix12by4 A = derivativeMatrix();
#ifdef EDM_ML_DEBUG
  edm::LogVerbatim("MuonSegFitMatrixDetails") << "[MuonSegFit::covarianceMatrix] weights matrix W: \n" << weights;      
  edm::LogVerbatim("MuonSegFitMatrixDetails") << "[MuonSegFit::covarianceMatrix] derivatives matrix A: \n" << A;      
#endif

  // (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);
#ifdef EDM_ML_DEBUG
  edm::LogVerbatim("MuonSegFitMatrixDetails") << "[MuonSegFit::covarianceMatrix] (AT W A): \n" << result;
#endif
  
  ok = result.Invert(); // inverts in place
  if ( !ok ) {
    edm::LogVerbatim("MuonSegFitMatrixDetails") << "[MuonSegFit::calculateError] Failed to invert matrix: \n" << result;      
    //    return ok;  //@@ SHOULD PASS THIS BACK TO CALLER?
  }
#ifdef EDM_ML_DEBUG
  edm::LogVerbatim("MuonSegFitMatrixDetails") << "[MuonSegFit::covarianceMatrix] (AT W A)^-1: \n" << result;      
#endif
  
  // reorder components to match TrackingRecHit interface (GEMSegment isa TrackingRecHit)
  // i.e. slopes first, then positions 
  AlgebraicSymMatrix flipped = flipErrors( result );
    
  return flipped;
}

MuonSegFit::SMatrix12by4 MuonSegFit::derivativeMatrix ( void  )

protected

Definition at line 323 of file MuonSegFit.cc.

References hits_, makeMuonMisalignmentScenario::matrix, z, and PV3DBase< T, PVType, FrameType >::z().

Referenced by covarianceMatrix(), and fitdone().

                                                    {
  
  SMatrix12by4 matrix; // 12x4, init to 0
  int row = 0;
  
  for( MuonRecHitContainer::const_iterator it = hits_.begin(); it != hits_.end(); ++it) {
    LocalPoint  lp         = (*it)->localPosition();
    
    float z = lp.z();

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

bool MuonSegFit::fit

(

void

)

Definition at line 14 of file MuonSegFit.cc.

References fit2(), fitdone(), fitdone_, fitlsq(), MaxHits2, gen::n, and nhits().

Referenced by trackingPlots.Iteration::modules(), and ~MuonSegFit().

                         {
  if ( fitdone() ) return fitdone_; // don't redo fit unnecessarily
  short n = nhits();
  if (n < 2){
    edm::LogVerbatim("MuonSegFit") << "[MuonSegFit::fit] - cannot fit just 1 hit!!";
  }
  else if (n == 2){
    fit2();
  }
  else if (2*n <= MaxHits2){
    fitlsq();
  }
  else {
    edm::LogVerbatim("MuonSegFit") << "[MuonSegFit::fit] - cannot fit more than "<< MaxHits2/2 <<" hits!!";
  }
  return fitdone_;
}

void MuonSegFit::fit2 ( void  )

private

Definition at line 32 of file MuonSegFit.cc.

References chi2_, PVValHelper::dz, fitdone_, hits_, intercept_, ndof_, setOutFromIP(), uslope_, vslope_, PV3DBase< T, PVType, FrameType >::x(), PV3DBase< T, PVType, FrameType >::y(), and PV3DBase< T, PVType, FrameType >::z().

Referenced by fit(), and fitdone().

                          {
  // 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)
  //
  // Now we will make two straight lines
  // one in xz-plane, another in yz-plane
  //       x = uz + c1 
  //       y = vz + c2
  // 1) Check whether hits are on the same layer
  // should be done before, so removed
  // -------------------------------------------

  MuonRecHitContainer::const_iterator ih = hits_.begin();
  // 2) Global Positions of hit 1 and 2 and
  //    Local  Positions of hit 1 and 2 w.r.t. reference GEM Eta Partition 
  // ---------------------------------------------------------------------
  LocalPoint h1pos = (*ih)->localPosition();
  ++ih;
  LocalPoint h2pos = (*ih)->localPosition();
  
  // 3) Now make straight line between the two points in local coords
  // ----------------------------------------------------------------
  float dz = h2pos.z()-h1pos.z();
  if(dz != 0.0) {
    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;

  // calculate local position (variable: intercept_)
  intercept_ = LocalPoint( uintercept, vintercept, 0.);
  
  // calculate the local direction (variable: localdir_)
  setOutFromIP();

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

  fitdone_ = true;
}

bool MuonSegFit::fitdone ( ) const

inline

Definition at line 97 of file MuonSegFit.h.

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

Referenced by fit().

{ return fitdone_; }

void MuonSegFit::fitlsq ( void  )

private

Definition at line 80 of file MuonSegFit.cc.

References TtFullHadDaughter::B, fitdone_, hits_, intercept_, LogTrace, convertSQLiteXML::ok, AlCaHLTBitMon_ParallelJobs::p, setChi2(), setOutFromIP(), uslope_, findQualityFiles::v, vslope_, PV3DBase< T, PVType, FrameType >::x(), PV3DBase< T, PVType, FrameType >::y(), z, and PV3DBase< T, PVType, FrameType >::z().

Referenced by fit(), and fitdone().

                            {
  // Linear least-squares fit to up to 6 GEM rechits, one per layer in a GEM chamber.
  // Comments adapted from Tim Cox' comments in the original  GEMSegAlgoSK algorithm.
  
  // Fit to the local x, y rechit coordinates in z projection
  // The strip measurement controls the precision of x
  // The wire measurement controls the precision of y.
  // Typical precision: u (strip, sigma~200um), v (wire, sigma~1cm)
  
  // 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()'. 

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

  MuonRecHitContainer::const_iterator ih = hits_.begin();
  
  // Loop over the GEMRecHits and make small (2x2) matrices used to fill the blockdiagonal covariance matrix E^-1
  for (ih = hits_.begin(); ih != hits_.end(); ++ih) {
    LocalPoint  lp         = (*ih)->localPosition();    
    // 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) = (*ih)->localPositionError().xx();
    IC(1,1) = (*ih)->localPositionError().yy();
    //@@ NOT SURE WHICH OFF-DIAGONAL ELEMENT MUST BE DEFINED BUT (1,0) WORKS
    //@@ (and SMatrix enforces symmetry)
    IC(1,0) = (*ih)->localPositionError().xy();
    // IC(0,1) = IC(1,0);
    
#ifdef EDM_ML_DEBUG
    edm::LogVerbatim("MuonSegFitMatrixDetails") << "[MuonSegFit::fit] 2x2 covariance matrix for this GEMRecHit :: [[" << IC(0,0) <<", "<< IC(0,1) <<"]["<< IC(1,0) <<","<<IC(1,1)<<"]]";
#endif

    // Invert covariance matrix (and trap if it fails!)
    bool ok = IC.Invert();
    if ( !ok ) {
      edm::LogVerbatim("MuonSegFitMatrixDetails") << "[MuonSegFit::fit] Failed to invert covariance matrix: \n" << IC;      
      //      return ok;  //@@ SHOULD PASS THIS BACK TO CALLER?
    }

    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;

  }

  SVector4 p;
  bool ok = M.Invert();
  if (!ok ){
    edm::LogVerbatim("MuonSegFitMatrixDetails") << "[MuonSegFit::fit] Failed to invert matrix: \n" << M;
    //    return ok; //@@ SHOULD PASS THIS BACK TO CALLER?
  }
  else {
    p = M * B;
  }

#ifdef EDM_ML_DEBUG
  LogTrace("MuonSegFitMatrixDetails") << "[MuonSegFit::fit] p = " 
                      << p(0) << ", " << p(1) << ", " << p(2) << ", " << p(3);
#endif
  
  // 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 MuonSegFit::flipErrors ( const SMatrixSym4 &  a )

protected

Definition at line 399 of file MuonSegFit.cc.

References a, and mps_fire::i.

Referenced by covarianceMatrix(), and fitdone().

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

  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
    }
  }

#ifdef EDM_ML_DEBUG
  edm::LogVerbatim("MuonSegFitMatrixDetails") << "[MuonSegFit::flipErrors] after copy:";
  edm::LogVerbatim("MuonSegFitMatrixDetails") << "(" << hold(1,1) << "  " << hold(1,2) << "  " << hold(1,3) << "  " << hold(1,4);
  edm::LogVerbatim("MuonSegFitMatrixDetails") << " " << hold(2,1) << "  " << hold(2,2) << "  " << hold(2,3) << "  " << hold(2,4);
  edm::LogVerbatim("MuonSegFitMatrixDetails") << " " << hold(3,1) << "  " << hold(3,2) << "  " << hold(3,3) << "  " << hold(3,4);
  edm::LogVerbatim("MuonSegFitMatrixDetails") << " " << hold(4,1) << "  " << hold(4,2) << "  " << hold(4,3) << "  " << hold(4,4) << ")";
#endif

  // 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)

#ifdef EDM_ML_DEBUG
  edm::LogVerbatim("MuonSegFitMatrixDetails") << "[MuonSegFit::flipErrors] after flip:";
  edm::LogVerbatim("MuonSegFitMatrixDetails") << "(" << hold(1,1) << "  " << hold(1,2) << "  " << hold(1,3) << "  " << hold(1,4);
  edm::LogVerbatim("MuonSegFitMatrixDetails") << " " << hold(2,1) << "  " << hold(2,2) << "  " << hold(2,3) << "  " << hold(2,4);
  edm::LogVerbatim("MuonSegFitMatrixDetails") << " " << hold(3,1) << "  " << hold(3,2) << "  " << hold(3,3) << "  " << hold(3,4);
  edm::LogVerbatim("MuonSegFitMatrixDetails") << " " << hold(4,1) << "  " << hold(4,2) << "  " << hold(4,3) << "  " << hold(4,4) << ")";
#endif

  return hold;
}

MuonRecHitContainer MuonSegFit::hits ( void  ) const

inline

Definition at line 90 of file MuonSegFit.h.

References hits_.

{ return hits_; }

LocalPoint MuonSegFit::intercept ( ) const

inline

Definition at line 95 of file MuonSegFit.h.

References intercept_.

{ return intercept_;}

LocalVector MuonSegFit::localdir ( ) const

inline

Definition at line 96 of file MuonSegFit.h.

References localdir_.

{ return localdir_;}

int MuonSegFit::ndof ( void  ) const

inline

Definition at line 94 of file MuonSegFit.h.

References ndof_.

{ return ndof_; }

size_t MuonSegFit::nhits ( void  ) const

inline

Definition at line 92 of file MuonSegFit.h.

References hits_.

Referenced by fit().

{ return hits_.size(); }

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

Definition at line 472 of file MuonSegFit.cc.

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

Referenced by setScaleXError().

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

double MuonSegFit::scaleXError ( void  ) const

inline

Definition at line 91 of file MuonSegFit.h.

References scaleXError_.

Referenced by weightMatrix().

{ return scaleXError_; }

void MuonSegFit::setChi2 ( void  )

private

Definition at line 235 of file MuonSegFit.cc.

References chi2_, hits_, intercept_, localdir_, ndof_, convertSQLiteXML::ok, uslope_, findQualityFiles::v, vslope_, PV3DBase< T, PVType, FrameType >::x(), PV3DBase< T, PVType, FrameType >::y(), z, and PV3DBase< T, PVType, FrameType >::z().

Referenced by fitdone(), and fitlsq().

                             {
  
  double chsq = 0.;

  MuonRecHitContainer::const_iterator ih;

  for (ih = hits_.begin(); ih != hits_.end(); ++ih) {
    LocalPoint lp = (*ih)->localPosition();
    
    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;
    
    SMatrixSym2 IC; // 2x2, init to 0

    IC(0,0) = (*ih)->localPositionError().xx();
    //    IC(0,1) = (*ih)->localPositionError().xy();
    IC(1,0) = (*ih)->localPositionError().xy();
    IC(1,1) = (*ih)->localPositionError().yy();
    //    IC(1,0) = IC(0,1);

#ifdef EDM_ML_DEBUG
    edm::LogVerbatim("MuonSegFitMatrixDetails") << "[MuonSegFit::setChi2] IC before = \n" << IC;
#endif

    // Invert covariance matrix
    bool ok = IC.Invert();
    if (!ok ){
      edm::LogVerbatim("MuonSegFitMatrixDetails") << "[MuonSegFit::setChi2] Failed to invert covariance matrix: \n" << IC;
      //      return ok;
    }
    chsq += du*du*IC(0,0) + 2.*du*dv*IC(0,1) + dv*dv*IC(1,1);
    
#ifdef EDM_ML_DEBUG
    edm::LogVerbatim("MuonSegFitMatrixDetails") << "[MuonSegFit::setChi2] IC after = \n" << IC;
    edm::LogVerbatim("MuonSegFit") << "[GEM RecHit ] Contribution to Chi^2 of this hit :: du^2*Cov(0,0) + 2*du*dv*Cov(0,1) + dv^2*IC(1,1) = "<<du*du<<"*"<<IC(0,0)<<" + 2.*"<<du<<"*"<<dv<<"*"<<IC(0,1)<<" + "<<dv*dv<<"*"<<IC(1,1)<<" = "<<chsq;
#endif    
  }
  
  // fill member variables
  chi2_ = chsq;
  ndof_ = 2.*hits_.size() - 4;

#ifdef EDM_ML_DEBUG
  edm::LogVerbatim("MuonSegFit") << "[MuonSegFit::setChi2] chi2/ndof = " << chi2_ << "/" << ndof_ ;
  edm::LogVerbatim("MuonSegFit") << "-----------------------------------------------------";  

  // check fit quality ... maybe write a separate function later on
  // that is there only for debugging issues

  edm::LogVerbatim("MuonSegFit") << "[GEM Segment with Local Direction = "<<localdir_<<" and Local Position "<<intercept_<<"] can be written as:";
  edm::LogVerbatim("MuonSegFit") << "[ x ] = "<<localdir_.x()<<" * t + "<<intercept_.x();
  edm::LogVerbatim("MuonSegFit") << "[ y ] = "<<localdir_.y()<<" * t + "<<intercept_.y();
  edm::LogVerbatim("MuonSegFit") << "[ z ] = "<<localdir_.z()<<" * t + "<<intercept_.z();
  edm::LogVerbatim("MuonSegFit") << "Now extrapolate to each of the GEMRecHits XY plane (so constant z = RH LP.z()) to obtain [x1,y1]";
#endif
}

void MuonSegFit::setOutFromIP ( void  )

protected

Definition at line 344 of file MuonSegFit.cc.

References PVValHelper::dx, BeamSpotFakeParameters_cfi::dxdz, PVValHelper::dy, BeamSpotFakeParameters_cfi::dydz, PVValHelper::dz, localdir_, PV3DBase< T, PVType, FrameType >::phi(), mathSSE::sqrt(), csvLumiCalc::unit, uslope_, and vslope_.

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_ = ( localDir ).unit();
#ifdef EDM_ML_DEBUG
  edm::LogVerbatim("MuonSegFit") << "[MuonSegFit::setOutFromIP] :: dxdz = uslope_ = "<<std::setw(9)<<uslope_<<" dydz = vslope_ = "<<std::setw(9)<<vslope_<<" local dir = "<<localDir;
  edm::LogVerbatim("MuonSegFit") << "[MuonSegFit::setOutFromIP] ::  ==> local dir = "<<localdir_<< " localdir.phi = "<<localdir_.phi();
#endif
}

void MuonSegFit::setScaleXError ( double  factor )

inline

Definition at line 78 of file MuonSegFit.h.

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

{ scaleXError_ = factor; }

MuonSegFit::SMatrixSym12 MuonSegFit::weightMatrix ( void  )

protected

Definition at line 296 of file MuonSegFit.cc.

References hits_, makeMuonMisalignmentScenario::matrix, convertSQLiteXML::ok, and scaleXError().

Referenced by covarianceMatrix(), and fitdone().

                                                {
  
  bool ok = true;

  SMatrixSym12 matrix = ROOT::Math::SMatrixIdentity(); // 12x12, init to 1's on diag

  int row = 0;
  
  for (MuonRecHitContainer::const_iterator it = hits_.begin(); it != hits_.end(); ++it) {
    // Note scaleXError allows rescaling the x error if necessary
    matrix(row, row)   = scaleXError()*(*it)->localPositionError().xx();
    matrix(row, row+1) = (*it)->localPositionError().xy();
    ++row;
    matrix(row, row-1) = (*it)->localPositionError().xy();
    matrix(row, row)   = (*it)->localPositionError().yy();
    ++row;
  }

  ok = matrix.Invert(); // invert in place
  if ( !ok ) {
    edm::LogVerbatim("MuonSegFitMatrixDetails") << "[MuonSegFit::weightMatrix] Failed to invert matrix: \n" << matrix;      
    //    return ok; //@@ SHOULD PASS THIS BACK TO CALLER?
  }
  return matrix;
}

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

Definition at line 464 of file MuonSegFit.cc.

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

Referenced by Rdev(), and setScaleXError().

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

float MuonSegFit::xfit

(

float

z

)

const

Definition at line 454 of file MuonSegFit.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 MuonSegFit::ydev	(	float	y,
		float	z
	)		const

Definition at line 468 of file MuonSegFit.cc.

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

Referenced by Rdev(), and setScaleXError().

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

float MuonSegFit::yfit

(

float

z

)

const

Definition at line 460 of file MuonSegFit.cc.

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

Referenced by setScaleXError().

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

Member Data Documentation

double MuonSegFit::chi2_

protected

Definition at line 126 of file MuonSegFit.h.

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

bool MuonSegFit::fitdone_

protected

Definition at line 129 of file MuonSegFit.h.

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

MuonRecHitContainer MuonSegFit::hits_

protected

Definition at line 121 of file MuonSegFit.h.

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

LocalPoint MuonSegFit::intercept_

protected

Definition at line 124 of file MuonSegFit.h.

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

LocalVector MuonSegFit::localdir_

protected

Definition at line 125 of file MuonSegFit.h.

Referenced by localdir(), setChi2(), and setOutFromIP().

const int MuonSegFit::MaxHits2 = 22

static

Definition at line 44 of file MuonSegFit.h.

Referenced by fit().

int MuonSegFit::ndof_

protected

Definition at line 127 of file MuonSegFit.h.

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

double MuonSegFit::scaleXError_

protected

Definition at line 128 of file MuonSegFit.h.

Referenced by scaleXError(), and setScaleXError().

float MuonSegFit::uslope_

protected

Definition at line 122 of file MuonSegFit.h.

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

float MuonSegFit::vslope_

protected

Definition at line 123 of file MuonSegFit.h.

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