ConstrainedTreeBuilderT Class Reference

#include <ConstrainedTreeBuilderT.h>

Public Member Functions
template<int nTrk>
RefCountedKinematicTree	buildTree (const std::vector< RefCountedKinematicParticle > &initialParticles, const std::vector< KinematicState > &finalStates, const RefCountedKinematicVertex vtx, const ROOT::Math::SMatrix< double, 3+7 *nTrk, 3+7 *nTrk, ROOT::Math::MatRepSym< double, 3+7 *nTrk > > &fCov) const
	ConstrainedTreeBuilderT ()
	~ConstrainedTreeBuilderT ()

Private Member Functions
RefCountedKinematicTree	buildRealTree (const RefCountedKinematicParticle virtualParticle, const RefCountedKinematicVertex vtx, const std::vector< RefCountedKinematicParticle > &particles) const

Static Private Member Functions
template<int nTrk>
static AlgebraicSymMatrix77	covarianceMatrix (const std::vector< RefCountedKinematicParticle > &rPart, const AlgebraicVector7 &newPar, const ROOT::Math::SMatrix< double, 3+7 *nTrk, 3+7 *nTrk, ROOT::Math::MatRepSym< double, 3+7 *nTrk > > &fitCov)

Private Attributes
VirtualKinematicParticleFactory	pFactory
KinematicVertexFactory	vFactory

Detailed Description

Class constructing te final output tree for the constrained vertex fitter. To be used by corresponding fitter only. Tree builders are scheduled for generalization: They should be inherited from the single generic class in the next version of the library.

Definition at line 15 of file ConstrainedTreeBuilderT.h.

Constructor & Destructor Documentation

ConstrainedTreeBuilderT::ConstrainedTreeBuilderT ( )

inline

Definition at line 20 of file ConstrainedTreeBuilderT.h.

{}

ConstrainedTreeBuilderT::~ConstrainedTreeBuilderT ( )

inline

Definition at line 22 of file ConstrainedTreeBuilderT.h.

References buildRealTree(), buildTree(), covarianceMatrix(), pseudoTop_cfi::finalStates, HadronAndPartonSelector_cfi::particles, and badGlobalMuonTaggersAOD_cff::vtx.

{}

Member Function Documentation

RefCountedKinematicTree ConstrainedTreeBuilderT::buildRealTree ( const RefCountedKinematicParticle  virtualParticle, const RefCountedKinematicVertex  vtx, const std::vector< RefCountedKinematicParticle > &  particles  ) const

private

Definition at line 8 of file ConstrainedTreeBuilderT.cc.

References KinematicTree::movePointerToTheTop(), KinematicTree::replaceCurrentParticle(), KinematicVertexFactory::vertex(), and vFactory.

Referenced by buildTree(), and ~ConstrainedTreeBuilderT().

{

//making a resulting tree:
 RefCountedKinematicTree resTree = ReferenceCountingPointer<KinematicTree>(new KinematicTree());

//fake production vertex:
 RefCountedKinematicVertex fVertex = vFactory.vertex();
 resTree->addParticle(fVertex, vtx, virtualParticle);

//adding final state
 for(std::vector<RefCountedKinematicParticle>::const_iterator il = particles.begin(); il != particles.end(); il++)
 {
  if((*il)->previousParticle()->correspondingTree() != 0)
  {
   KinematicTree * tree = (*il)->previousParticle()->correspondingTree();
   tree->movePointerToTheTop();
   tree->replaceCurrentParticle(*il);
   RefCountedKinematicVertex cdVertex = resTree->currentDecayVertex();
   resTree->addTree(cdVertex, tree);
  }else{
   RefCountedKinematicVertex ffVertex = vFactory.vertex();
   resTree->addParticle(vtx,ffVertex,*il);
  }
 }
 return resTree;
}

template<int nTrk>

RefCountedKinematicTree ConstrainedTreeBuilderT::buildTree	(	const std::vector< RefCountedKinematicParticle > &	initialParticles,
		const std::vector< KinematicState > &	finalStates,
		const RefCountedKinematicVertex	vtx,
		const ROOT::Math::SMatrix< double, 3+7 *nTrk, 3+7 *nTrk, ROOT::Math::MatRepSym< double, 3+7 *nTrk > > &	fCov
	)		const

Method constructing tree out of set of refitted states, vertex, and full covariance matrix.

Definition at line 60 of file ConstrainedTreeBuilderT.h.

References a, buildRealTree(), ALCARECOTkAlJpsiMuMu_cff::charge, HiEvtPlane_cfi::chi2, mps_fire::i, LogDebug, DetachedQuadStep_cff::magneticField, gen::n, hcaldqm::flag::nState, AlCaHLTBitMon_ParallelJobs::p, VirtualKinematicParticleFactory::particle(), pFactory, mathSSE::sqrt(), badGlobalMuonTaggersAOD_cff::vtx, and z.

Referenced by KinematicConstrainedVertexFitterT< nTrk, nConstraint >::fit(), and ~ConstrainedTreeBuilderT().

{
  if (!vertex->vertexIsValid()) {
       LogDebug("RecoVertex/ConstrainedTreeBuilder")
    << "Vertex is invalid\n";
       return ReferenceCountingPointer<KinematicTree>(new KinematicTree());
  }
  AlgebraicVector3 vtx;
  vtx(0) = vertex->position().x();
  vtx(1) = vertex->position().y();
  vtx(2) = vertex->position().z();
  AlgebraicMatrix33 vertexCov = fullCov.template Sub<ROOT::Math::SMatrix<double, 3> >(0,0);

// cout << fullCov<<endl;
//  cout << "RecoVertex/ConstrainedTreeBuilder"<<vtx<<endl;

 double ent = 0.;
 int charge = 0;
  AlgebraicVector7 virtualPartPar;
  virtualPartPar(0) = vertex->position().x();
  virtualPartPar(1) = vertex->position().y();
  virtualPartPar(2) = vertex->position().z();

//making refitted particles out of refitted states.
//none of the operations above violates the order of particles

  ROOT::Math::SMatrix<double,7,7,ROOT::Math::MatRepStd<double,7,7> >  aMatrix;
  ROOT::Math::SMatrix<double,7,7,ROOT::Math::MatRepStd<double,7,7> >  aMatrixT;
  aMatrix(3,3) =  aMatrixT(3,3) = 1;
  aMatrix(4,4) =  aMatrixT(4,4)  = 1;
  aMatrix(5,5) =  aMatrixT(5,5)  = 1;
  aMatrix(6,6) =  aMatrixT(6,6)  = 1;
  ROOT::Math::SMatrix<double,7,3,ROOT::Math::MatRepStd<double,7,3> > bMatrix;
  ROOT::Math::SMatrix<double,3,7,ROOT::Math::MatRepStd<double,3,7> > bMatrixT;
  bMatrix(0,0) =  bMatrixT(0,0) = 1;
  bMatrix(1,1) =  bMatrixT(1,1) = 1;
  bMatrix(2,2) =  bMatrixT(2,2) = 1;
  AlgebraicSymMatrix77 trackParCov;
  ROOT::Math::SMatrix<double,3,7,ROOT::Math::MatRepStd<double,3,7> > vtxTrackCov;
  AlgebraicSymMatrix77 nCovariance;
  // AlgebraicSymMatrix77 tmp;

  std::vector<RefCountedKinematicParticle>::const_iterator i = initialParticles.begin();
  std::vector<KinematicState>::const_iterator iStates = finalStates.begin();
  std::vector<RefCountedKinematicParticle> rParticles;
  int n=0;
  // assert(initialParticles.size()==nTrk);
  for( ; i != initialParticles.end() && iStates != finalStates.end(); ++i,++iStates)
  {
    AlgebraicVector7 p = iStates->kinematicParameters().vector();
    double a = - iStates->particleCharge() *
    iStates->magneticField()->inInverseGeV(iStates->globalPosition()).z();

    aMatrix(4,0) = aMatrixT(0,4) = -a;
    aMatrix(3,1) = aMatrixT(1,3) =  a;
    bMatrix(4,0) = bMatrixT(0,4) =  a;
    bMatrix(3,1) = bMatrixT(1,3) = -a;

    AlgebraicVector7 par = aMatrix*p + bMatrix * vtx;

    trackParCov = fullCov.template Sub<AlgebraicSymMatrix77>(3+n*7,3+n*7);
    vtxTrackCov = fullCov.template Sub<ROOT::Math::SMatrix<double, 3, 7> >(0,3+n*7);
    ROOT::Math::AssignSym::Evaluate(nCovariance,
                    aMatrix * trackParCov * aMatrixT
                    + aMatrix * ROOT::Math::Transpose(vtxTrackCov) * bMatrixT
                    + bMatrix * vtxTrackCov * aMatrixT 
                    + bMatrix * vertexCov * bMatrixT
                    );
    /*
    ROOT::Math::AssignSym::Evaluate(tmp, aMatrix * ROOT::Math::Transpose(vtxTrackCov) * bMatrixT);
    nCovariance+=tmp;
    ROOT::Math::AssignSym::Evaluate(tmp, bMatrix * vtxTrackCov * aMatrixT);
    nCovariance+=tmp;
    ROOT::Math::AssignSym::Evaluate(tmp, bMatrix * vertexCov * bMatrixT);
    nCovariance+=tmp;
    */

    KinematicState stateAtVertex(KinematicParameters(par),
                 KinematicParametersError(nCovariance),
                 iStates->particleCharge(), iStates->magneticField());
    rParticles.push_back((*i)->refittedParticle(stateAtVertex, vertex->chiSquared(), vertex->degreesOfFreedom()));
    
    virtualPartPar(3) += par(3);
    virtualPartPar(4) += par(4);
    virtualPartPar(5) += par(5);
    ent += sqrt(par(6)*par(6) +  par(3)*par(3)+par(4)*par(4)+par(5)*par(5) );
    charge += iStates->particleCharge();

    ++n;

  }

 //total reconstructed mass
  double differ = ent*ent - (virtualPartPar(3)*virtualPartPar(3) + virtualPartPar(5)*virtualPartPar(5) + virtualPartPar(4)*virtualPartPar(4));
  if(differ>0.) {
    virtualPartPar(6) = sqrt(differ);
  } else {
   LogDebug("ConstrainedTreeBuilder")
    << "Fit failed: Current precision does not allow to calculate the mass\n";
   return ReferenceCountingPointer<KinematicTree>(new KinematicTree());
  }

 // covariance matrix:

  AlgebraicSymMatrix77 cov = this->covarianceMatrix<nTrk>(rParticles,virtualPartPar,fullCov);

  KinematicState nState(KinematicParameters(virtualPartPar),
            KinematicParametersError(cov),
            charge, initialParticles[0]->magneticField());

 //newborn kinematic particle
  float chi2 = vertex->chiSquared();
  float ndf = vertex->degreesOfFreedom();
  KinematicParticle * zp = 0;
  RefCountedKinematicParticle virtualParticle = pFactory.particle(nState,chi2,ndf,zp);

  return buildRealTree(virtualParticle, vertex, rParticles);
}

template<int nTrk>

AlgebraicSymMatrix77 ConstrainedTreeBuilderT::covarianceMatrix ( const std::vector< RefCountedKinematicParticle > &  rPart, const AlgebraicVector7 &  newPar, const ROOT::Math::SMatrix< double, 3+7 *nTrk, 3+7 *nTrk, ROOT::Math::MatRepSym< double, 3+7 *nTrk > > &  fitCov  )

staticprivate

Metod to reconstruct the full covariance matrix of the resulting particle.

Definition at line 184 of file ConstrainedTreeBuilderT.h.

References mps_fire::i, DetachedQuadStep_cff::magneticField, findQualityFiles::size, mathSSE::sqrt(), create_public_lumi_plots::transform, and pileupCalc::upper.

Referenced by ~ConstrainedTreeBuilderT().

 {

   typedef ROOT::Math::SMatrix<double,3+7*nTrk,3+7*nTrk,ROOT::Math::MatRepSym<double,3+7*nTrk> > FitCov;
  //constructing the full matrix using the simple fact
  //that we have never broken the order of tracks
  // during our fit.
  
  int size = nTrk;  

  if ( int(rPart.size())!=size) throw "error in ConstrainedTreeBuilderT ";

  //global propagation to the vertex position
  //Jacobian is done for all the parameters together
  ROOT::Math::SMatrix<double,3+7*nTrk> jac;
  jac(0,0) = 1;
  jac(1,1) = 1;
  jac(2,2) = 1;
  ROOT::Math::SMatrix<double,3,7> upper;
  ROOT::Math::SMatrix<double,7>  diagonal;
  for(  int i_int=0; i_int!=size; ++i_int) {
    RefCountedKinematicParticle const & i = rPart[i_int];   
    //vertex position related components of the matrix
    double a_i = - (i)->currentState().particleCharge() *
      (i)->magneticField()->inInverseGeV((i)->currentState().globalPosition()).z();
    upper(0,0) = 1;
    upper(1,1) = 1;
    upper(2,2) = 1;
    upper(1,3) = -a_i;
    upper(0,4) = a_i;
    jac.Place_at(upper,0,3+i_int*7);
    
    diagonal(3,3) = 1;
    diagonal(4,4) = 1;
    diagonal(5,5) = 1;
    diagonal(6,6) = 1;
    diagonal(1,3) = a_i;
    diagonal(0,4) = -a_i;
    jac.Place_at(diagonal,3+i_int*7,3+i_int*7);
  }
  
  // jacobian is constructed in such a way, that
  // right operation for transformation will be
  // fitCov.similarityT(jac)
  // WARNING: normal similarity operation is
  // not valid in this case
  //now making reduced matrix:
  // int vSize = rPart.size();
  FitCov const & fit_cov_sym = fitCov;
  /*
    for(int i = 0; i<7*vSize+3; ++i)
    {
    for(int j = 0; j<7*vSize+3; ++j)
    {if(i<=j) fit_cov_sym(i,j) = fitCov(i,j);}
    }
  */
  
  ROOT::Math::SMatrix<double,4*nTrk+3,4*nTrk+3, ROOT::Math::MatRepSym<double,4*nTrk+3> > reduced;
  FitCov transform=ROOT::Math::SimilarityT(jac,fit_cov_sym); // similarityT???
  
  //jacobian to add matrix components
  ROOT::Math::SMatrix<double,7,4*nTrk+3> jac_t;
  jac_t(0,0) = 1.;
  jac_t(1,1) = 1.;
  jac_t(2,2) = 1.;
  

  
  double energy_global = sqrt(newPar(3)*newPar(3)+newPar(4)*newPar(4) + newPar(5)*newPar(5)+newPar(6)*newPar(6));
  for(int il_int = 0; il_int!=size; ++il_int) {
    RefCountedKinematicParticle const & rs = rPart[il_int];
    //jacobian components:
    int off1=3; int off2=il_int*4+3;
    jac_t(off1+0,off2+0) = 1.;
    jac_t(off1+1,off2+1) = 1.;
    jac_t(off1+2,off2+2) = 1.;
    
    //non-trival elements: mass correlations:
    AlgebraicVector7 l_Par = (rs)->currentState().kinematicParameters().vector();
    double energy_local  = sqrt(l_Par(6)*l_Par(6) + l_Par(3)*l_Par(3) + l_Par(4)*l_Par(4) + l_Par(5)*l_Par(5));
    jac_t(off1+3,off2+3) = energy_global*l_Par(6)/(newPar(6)*energy_local);
    jac_t(off1+3,off2+0) = ((energy_global*l_Par(3)/energy_local) - newPar(3))/newPar(6);
    jac_t(off1+3,off2+1) = ((energy_global*l_Par(4)/energy_local) - newPar(4))/newPar(6);
    jac_t(off1+3,off2+2) = ((energy_global*l_Par(5)/energy_local) - newPar(5))/newPar(6);
  }

  for(int i = 0; i<7;++i)
    for(int j =0; j<7; ++j)
      reduced(i,j)  = transform(i+3, j+3);

  for(int i = 1; i<size; i++) {
    //non-trival elements: mass correlations:
    //upper row and right column

    int off1=0;
    int off2=3+4*i;
    for(int l1 = 0; l1<3;++l1) 
      for(int l2 = 0; l2<4;++l2)
    reduced(off1+l1,off2+l2) = transform(3+l1,6+7*i +l2);

    //diagonal elements
    off1=off2=3+4*i;
    for(int l1 = 0; l1<4;++l1)
      for(int l2 = 0; l2<4;++l2)
    reduced(off1+l1,off2+l2) = transform(6+7*i+l1, 6+7*i+l2);

     //off diagonal elements
   for(int j = 1; j<size; j++) {
      off1 =  3+4*(i-1); off2=3+4*j;
      for(int l1 = 0; l1<4;++l1)
    for(int l2 = 0; l2<4;++l2)
      reduced(off1+l1,off2+l2)  = transform(6+7*(i-1)+l1,6+7*j+l2);
    }

  }
    
  AlgebraicSymMatrix77 ret;
  ROOT::Math::AssignSym::Evaluate(ret, jac_t*reduced*ROOT::Math::Transpose(jac_t));
  return ret;
}

Member Data Documentation

VirtualKinematicParticleFactory ConstrainedTreeBuilderT::pFactory

private

Definition at line 50 of file ConstrainedTreeBuilderT.h.

Referenced by buildTree().

KinematicVertexFactory ConstrainedTreeBuilderT::vFactory

private

Definition at line 51 of file ConstrainedTreeBuilderT.h.

Referenced by buildRealTree().