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Public Member Functions | Private Types | Private Member Functions | Private Attributes

PFClusterShapeAlgo Class Reference

#include <PFClusterShapeAlgo.h>

List of all members.

Public Member Functions

reco::ClusterShapeCollectionmakeClusterShapes (edm::Handle< reco::PFClusterCollection > clusterHandle, edm::Handle< reco::PFRecHitCollection > rechitHandle, const CaloSubdetectorGeometry *barrelGeo_p, const CaloSubdetectorTopology *barrelTop_p, const CaloSubdetectorGeometry *endcapGeo_p, const CaloSubdetectorTopology *endcapTop_p)
 PFClusterShapeAlgo (bool useFractions, double w0)
 ~PFClusterShapeAlgo ()

Private Types

enum  Direction {
  N, NE, E, SE,
  S, SW, W, NW
}
enum  GeomTopoIndex { BARREL = 0, ENDCAP = 1 }
typedef std::map< DetId,
RecHitWithFraction
RecHitMap

Private Member Functions

double addMapEnergies (int etaIndexLow, int etaIndexHigh, int phiIndexLow, int phiIndexHigh)
void covariances ()
void fill5x5Map ()
void find_e2x2 ()
void find_e2x5Bottom ()
void find_e2x5Left ()
void find_e2x5Right ()
void find_e2x5Top ()
void find_e3x2 ()
void find_e3x3 ()
void find_e4x4 ()
void find_e5x5 ()
void find_eMax_e2nd ()
int findPFRHIndexFromDetId (unsigned int id)
const reco::PFRecHitFractiongetFractionFromDetId (const DetId &id)
reco::ClusterShape makeClusterShape ()

Private Attributes

double covEtaEta_
double covEtaPhi_
double covPhiPhi_
reco::PFClusterRef currentCluster_p
unsigned int currentClusterIndex_
edm::Handle
< reco::PFRecHitCollection
currentRecHit_v_p
double e2nd_
DetId e2ndId_
double e2x2_
double e2x5Bottom_
double e2x5Left_
double e2x5Right_
double e2x5Top_
double e3x2_
double e3x2Ratio_
double e3x3_
double e4x4_
double e5x5_
double eMax_
Direction eMaxDir
DetId eMaxId_
unsigned int geomIndex
std::vector< const
CaloSubdetectorGeometry * > 
geomVector
RecHitWithFraction map5x5 [5][5]
math::XYZVector meanPosition_
unsigned int topoIndex
std::vector< const
CaloSubdetectorTopology * > 
topoVector
double totalE_
bool useFractions_
double w0_

Detailed Description

Definition at line 37 of file PFClusterShapeAlgo.h.


Member Typedef Documentation

Definition at line 39 of file PFClusterShapeAlgo.h.


Member Enumeration Documentation

Enumerator:
N 
NE 
E 
SE 
S 
SW 
W 
NW 

Definition at line 41 of file PFClusterShapeAlgo.h.

{ N, NE, E, SE, S, SW, W, NW };
Enumerator:
BARREL 
ENDCAP 

Definition at line 42 of file PFClusterShapeAlgo.h.

{ BARREL = 0, ENDCAP = 1 }; 

Constructor & Destructor Documentation

PFClusterShapeAlgo::PFClusterShapeAlgo ( bool  useFractions,
double  w0 
) [explicit]

Definition at line 3 of file PFClusterShapeAlgo.cc.

References useFractions_, and w0_.

{
  useFractions_ = useFractions;
  w0_ = w0;
}
PFClusterShapeAlgo::~PFClusterShapeAlgo ( )

Definition at line 9 of file PFClusterShapeAlgo.cc.

{
}

Member Function Documentation

double PFClusterShapeAlgo::addMapEnergies ( int  etaIndexLow,
int  etaIndexHigh,
int  phiIndexLow,
int  phiIndexHigh 
) [private]

Definition at line 208 of file PFClusterShapeAlgo.cc.

References RecHitWithFraction::energy, relval_parameters_module::energy, i, j, and map5x5.

Referenced by find_e2x2(), find_e2x5Bottom(), find_e2x5Left(), find_e2x5Right(), find_e2x5Top(), find_e3x2(), find_e3x3(), find_e4x4(), and find_e5x5().

{
  const int etaLow  = etaIndexLow  + 2;
  const int etaHigh = etaIndexHigh + 2;
  const int phiLow  = phiIndexLow  + 2;
  const int phiHigh = phiIndexHigh + 2;

  double energy = 0;

  for (int i = etaLow; i <= etaHigh; ++i)
    {
      for (int j = phiLow; j <= phiHigh; ++j)
        {
          energy += map5x5[i][j].energy;
        }
    }
  return energy;
}
void PFClusterShapeAlgo::covariances ( ) [private]

Definition at line 299 of file PFClusterShapeAlgo.cc.

References covEtaEta_, covEtaPhi_, covPhiPhi_, RecoTauValidation_cfi::denominator, dPhi(), relval_parameters_module::energy, i, j, create_public_lumi_plots::log, map5x5, max(), meanPosition_, Geom::pi(), position, totalE_, Geom::twoPi(), w(), and w0_.

Referenced by makeClusterShape().

{
  double numeratorEtaEta = 0;
  double numeratorEtaPhi = 0;
  double numeratorPhiPhi = 0;
  double denominator     = 0;

  for (int i = 0; i < 5; ++i)
    {
      for (int j = 0; j < 5; ++j)
        {
          const math::XYZVector & crystalPosition(map5x5[i][j].position);
          
          double dPhi = crystalPosition.phi() - meanPosition_.phi();
          if (dPhi > + Geom::pi()) { dPhi = Geom::twoPi() - dPhi; }
          if (dPhi < - Geom::pi()) { dPhi = Geom::twoPi() - dPhi; }

          const double dEta = crystalPosition.eta() - meanPosition_.eta();
          
          const double w = std::max(0.0, w0_ + log(map5x5[i][j].energy / totalE_));
          
          denominator += w;
          numeratorEtaEta += w * dEta * dEta;
          numeratorEtaPhi += w * dEta * dPhi;
          numeratorPhiPhi += w * dPhi * dPhi;
        }
    }

  covEtaEta_ = numeratorEtaEta / denominator;
  covEtaPhi_ = numeratorEtaPhi / denominator;
  covPhiPhi_ = numeratorPhiPhi / denominator;
}
void PFClusterShapeAlgo::fill5x5Map ( ) [private]

Definition at line 155 of file PFClusterShapeAlgo.cc.

References currentRecHit_v_p, RecHitWithFraction::detId, eMaxId_, RecHitWithFraction::energy, findPFRHIndexFromDetId(), reco::PFRecHitFraction::fraction(), getFractionFromDetId(), CaloNavigator< T >::home(), i, getHLTprescales::index, j, map5x5, meanPosition_, CaloNavigator< T >::offsetBy(), RecHitWithFraction::position, position, topoIndex, topoVector, totalE_, and useFractions_.

Referenced by makeClusterShape().

{
  // first get a navigator to the central element
  CaloNavigator<DetId> position = CaloNavigator<DetId>(eMaxId_, topoVector[topoIndex]);

  meanPosition_ = math::XYZVector(0.0, 0.0, 0.0);
  totalE_ = 0;

  for (int i = 0; i < 5; ++i)
    {
      for (int j = 0; j < 5; ++j)
        {
          position.home();
          position.offsetBy(i - 2, j - 2);

          RecHitWithFraction newEntry;
          newEntry.detId = DetId(0);
          newEntry.energy = 0.0;
          newEntry.position = math::XYZVector(0, 0, 0);

          if (*position != DetId(0)) // if this is a valid detId...
            {
              // ...find the corresponding PFRecHit index
              const int index = findPFRHIndexFromDetId((*position).rawId());

              if (index >= 0) // if a PFRecHit exists for this detId
                {
                  double fraction = 1.0;
                  if (useFractions_) // if the algorithm should use fractions
                    { 
                      fraction = 0.0;
                      const reco::PFRecHitFraction * fraction_p = getFractionFromDetId(*position);
                      if (fraction_p) { fraction = fraction_p->fraction(); }
                    }

                  const reco::PFRecHitRef rhRef(currentRecHit_v_p, index);
                  const math::XYZVector crystalPosition(rhRef->position());
                  const double energyFraction =  rhRef->energy() * fraction;

                  newEntry.detId = *position;
                  newEntry.energy = energyFraction;
                  newEntry.position = crystalPosition;

                  meanPosition_ = meanPosition_ + crystalPosition * energyFraction; 
                  totalE_ += energyFraction;
                }
            }
          map5x5[i][j] = newEntry;
        }
    }
  meanPosition_ /= totalE_;
}
void PFClusterShapeAlgo::find_e2x2 ( ) [private]

Definition at line 242 of file PFClusterShapeAlgo.cc.

References addMapEnergies(), e2x2_, eMaxDir, NE, NW, SE, and SW.

Referenced by makeClusterShape().

{
  std::map<double, Direction> directionMap;

  directionMap[addMapEnergies(-1, +0, -1, +0)] = SE;
  directionMap[addMapEnergies(-1, +0, +0, +1)] = NE;
  directionMap[addMapEnergies(+0, +1, -1, +0)] = SW;
  directionMap[addMapEnergies(+0, +1, +0, +1)] = NW;

  const std::map<double, Direction>::reverse_iterator eMaxDir_it = directionMap.rbegin();

  eMaxDir = eMaxDir_it->second;

  e2x2_ = eMaxDir_it->first;
}
void PFClusterShapeAlgo::find_e2x5Bottom ( ) [private]

Definition at line 232 of file PFClusterShapeAlgo.cc.

References addMapEnergies(), and e2x5Bottom_.

Referenced by makeClusterShape().

{ e2x5Bottom_ = addMapEnergies(+1, +2, -2, +2); }
void PFClusterShapeAlgo::find_e2x5Left ( ) [private]

Definition at line 230 of file PFClusterShapeAlgo.cc.

References addMapEnergies(), and e2x5Left_.

Referenced by makeClusterShape().

{ e2x5Left_   = addMapEnergies(-2, +2, -2, -1); }
void PFClusterShapeAlgo::find_e2x5Right ( ) [private]

Definition at line 229 of file PFClusterShapeAlgo.cc.

References addMapEnergies(), and e2x5Right_.

Referenced by makeClusterShape().

{ e2x5Right_  = addMapEnergies(-2, +2, +1, +2); }
void PFClusterShapeAlgo::find_e2x5Top ( ) [private]

Definition at line 231 of file PFClusterShapeAlgo.cc.

References addMapEnergies(), and e2x5Top_.

Referenced by makeClusterShape().

{ e2x5Top_    = addMapEnergies(-2, -1, -2, +2); }
void PFClusterShapeAlgo::find_e3x2 ( ) [private]

Definition at line 258 of file PFClusterShapeAlgo.cc.

References addMapEnergies(), RecoTauValidation_cfi::denominator, dir, E, e3x2_, e3x2Ratio_, RecHitWithFraction::energy, map5x5, N, S, and W.

Referenced by makeClusterShape().

{
  // Find the direction of the highest energy neighbour
  std::map<double, Direction> directionMap;
  directionMap[map5x5[2][3].energy] = N; 
  directionMap[map5x5[2][1].energy] = S;
  directionMap[map5x5[1][2].energy] = E;
  directionMap[map5x5[3][2].energy] = W;
  // Maps are sorted in ascending order - get the last element
  const Direction dir = directionMap.rbegin()->second;

  if (dir == N) 
    {
      e3x2_ = addMapEnergies(-1, +1, +0, +1);
      const double numerator   = map5x5[3][2].energy + map5x5[1][2].energy;
      const double denominator = map5x5[1][3].energy + map5x5[3][3].energy + 0.5;
      e3x2Ratio_ = numerator / denominator;
    }
  else if (dir == S)
    {
      e3x2_ = addMapEnergies(-1, +1, -1, +0);
      const double numerator   = map5x5[3][2].energy + map5x5[1][2].energy;
      const double denominator = map5x5[1][1].energy + map5x5[3][1].energy + 0.5;
      e3x2Ratio_ = numerator / denominator;
    }
  else if (dir == W)
    {
      e3x2_ = addMapEnergies(+0, +1, -1, +1);
      const double numerator   = map5x5[2][3].energy + map5x5[2][1].energy;
      const double denominator = map5x5[3][3].energy + map5x5[3][1].energy + 0.5;
      e3x2Ratio_ = numerator / denominator;
    }
  else if (dir == E)
    {
      e3x2_ = addMapEnergies(-1, +0, -1, +1);
      const double numerator   = map5x5[2][3].energy + map5x5[2][1].energy;
      const double denominator = map5x5[1][1].energy + map5x5[1][3].energy + 0.5;
      e3x2Ratio_ = numerator / denominator;
    }
}
void PFClusterShapeAlgo::find_e3x3 ( ) [private]

Definition at line 227 of file PFClusterShapeAlgo.cc.

References addMapEnergies(), and e3x3_.

Referenced by makeClusterShape().

{ e3x3_       = addMapEnergies(-1, +1, -1, +1); }
void PFClusterShapeAlgo::find_e4x4 ( ) [private]

Definition at line 234 of file PFClusterShapeAlgo.cc.

References addMapEnergies(), e4x4_, eMaxDir, NE, NW, SE, and SW.

Referenced by makeClusterShape().

{
  if (eMaxDir == SE) { e4x4_ = addMapEnergies(-2, +1, -2, +1); return; }
  if (eMaxDir == NE) { e4x4_ = addMapEnergies(-2, +1, -1, +2); return; }
  if (eMaxDir == SW) { e4x4_ = addMapEnergies(-1, +2, -2, +1); return; }
  if (eMaxDir == NW) { e4x4_ = addMapEnergies(-1, +2, -1, +2); return; }
}
void PFClusterShapeAlgo::find_e5x5 ( ) [private]

Definition at line 228 of file PFClusterShapeAlgo.cc.

References addMapEnergies(), and e5x5_.

Referenced by makeClusterShape().

{ e5x5_       = addMapEnergies(-2, +2, -2, +2); }
void PFClusterShapeAlgo::find_eMax_e2nd ( ) [private]

Definition at line 96 of file PFClusterShapeAlgo.cc.

References currentCluster_p, e2nd_, e2ndId_, eMax_, and eMaxId_.

Referenced by makeClusterShape().

{
  std::map<double, DetId> energyMap;

  // First get the RecHitFractions:
  const std::vector<reco::PFRecHitFraction> & fraction_v = currentCluster_p->recHitFractions();
  // For every one of them...
  for (std::vector<reco::PFRecHitFraction>::const_iterator it = fraction_v.begin(); it != fraction_v.end(); ++it)
    {
      // ...find the corresponding rechit:
      // const reco::PFRecHit & rechit = (*currentRecHit_v_p)[it->recHitIndex()];
      const reco::PFRecHitRef rechit = it->recHitRef();
      // ...and DetId:
      const DetId rechitDetId = DetId(rechit->detId());
      // Make the new Pair and put it in the map:
      energyMap[rechit->energy()] = rechitDetId;
    }
  // maps are sorted in ascending order so get the last two elements:
  std::map<double, DetId>::reverse_iterator it = energyMap.rbegin();
  eMax_   = it->first;
  eMaxId_ = it->second;
  it++;
  e2nd_   = it->first;
  e2ndId_ = it->second;
}
int PFClusterShapeAlgo::findPFRHIndexFromDetId ( unsigned int  id) [private]

Definition at line 122 of file PFClusterShapeAlgo.cc.

References currentRecHit_v_p, errorMatrix2Lands_multiChannel::id, getHLTprescales::index, and gen::k.

Referenced by fill5x5Map().

{
  int index = -1; // need some negative number
  for (unsigned int k = 0; k < currentRecHit_v_p->size(); ++k)
    {
      if ((*currentRecHit_v_p)[k].detId() == id)
        {
          index = static_cast<int>(k);
          break;
        }
    }
  return index;
}
const reco::PFRecHitFraction * PFClusterShapeAlgo::getFractionFromDetId ( const DetId id) [private]

Definition at line 137 of file PFClusterShapeAlgo.cc.

References currentCluster_p.

Referenced by fill5x5Map().

{
  const std::vector< reco::PFRecHitFraction > & fraction_v = currentCluster_p->recHitFractions();
  for (std::vector<reco::PFRecHitFraction>::const_iterator it = fraction_v.begin(); it != fraction_v.end(); ++it)
    {
      //const unsigned int rhIndex = it->recHitIndex();
      //reco::PFRecHitRef rh_p(currentRecHit_v_p, rhIndex);
      const reco::PFRecHitRef rh_p = it->recHitRef();
      const DetId rhDetId = DetId(rh_p->detId());
      if (rhDetId == id) 
        { 
          return &(*it); 
        }
    }
  return 0;
}
reco::ClusterShape PFClusterShapeAlgo::makeClusterShape ( ) [private]

Definition at line 60 of file PFClusterShapeAlgo.cc.

References covariances(), covEtaEta_, covEtaPhi_, covPhiPhi_, e2nd_, e2ndId_, e2x2_, e2x5Bottom_, e2x5Left_, e2x5Right_, e2x5Top_, e3x2_, e3x2Ratio_, e3x3_, e4x4_, e5x5_, eMax_, eMaxId_, fill5x5Map(), find_e2x2(), find_e2x5Bottom(), find_e2x5Left(), find_e2x5Right(), find_e2x5Top(), find_e3x2(), find_e3x3(), find_e4x4(), find_e5x5(), and find_eMax_e2nd().

Referenced by makeClusterShapes().

{
  find_eMax_e2nd();
  fill5x5Map();
  
  find_e2x2();
  find_e3x2();
  find_e3x3();
  find_e4x4();
  find_e5x5();
  
  find_e2x5Right();
  find_e2x5Left();
  find_e2x5Top();
  find_e2x5Bottom();
  
  covariances();
  
  double dummyLAT = 0;
  double dummyEtaLAT = 0;
  double dummyPhiLAT = 0;
  double dummyA20 = 0;
  double dummyA42 = 0;

  std::vector<double> dummyEnergyBasketFractionEta_v;
  std::vector<double> dummyEnergyBasketFractionPhi_v;

  return reco::ClusterShape(covEtaEta_, covEtaPhi_, covPhiPhi_, 
                            eMax_, eMaxId_, e2nd_, e2ndId_,
                            e2x2_, e3x2_, e3x3_, e4x4_, e5x5_, 
                            e2x5Right_, e2x5Left_, e2x5Top_, e2x5Bottom_, e3x2Ratio_,
                            dummyLAT, dummyEtaLAT, dummyPhiLAT, dummyA20, dummyA42,
                            dummyEnergyBasketFractionEta_v, dummyEnergyBasketFractionPhi_v);
}
reco::ClusterShapeCollection * PFClusterShapeAlgo::makeClusterShapes ( edm::Handle< reco::PFClusterCollection clusterHandle,
edm::Handle< reco::PFRecHitCollection rechitHandle,
const CaloSubdetectorGeometry barrelGeo_p,
const CaloSubdetectorTopology barrelTop_p,
const CaloSubdetectorGeometry endcapGeo_p,
const CaloSubdetectorTopology endcapTop_p 
)

Definition at line 14 of file PFClusterShapeAlgo.cc.

References BARREL, currentCluster_p, currentClusterIndex_, currentRecHit_v_p, ENDCAP, geomIndex, geomVector, i, makeClusterShape(), topoIndex, and topoVector.

{
  static const float etaEndOfBarrel = 1.497;

  topoVector.push_back(the_barrelTop_p);
  topoVector.push_back(the_endcapTop_p);
  geomVector.push_back(the_barrelGeo_p);
  geomVector.push_back(the_endcapGeo_p);

  reco::ClusterShapeCollection * shape_v_p = new reco::ClusterShapeCollection();

  currentRecHit_v_p = rechitHandle;

  for (unsigned int i = 0; i < clusterHandle->size(); ++i)
    {
      // Make each cluster the "current" cluster
      currentCluster_p = reco::PFClusterRef(clusterHandle, i);
      currentClusterIndex_ = i;

      // Find the right topology to use with this cluster
      topoIndex = BARREL;
      geomIndex = BARREL;
      const math::XYZVector currentClusterPos(currentCluster_p->position());
      if (fabs(currentClusterPos.eta()) > etaEndOfBarrel)
        {
          topoIndex = ENDCAP;
          geomIndex = ENDCAP;
        }

      // Create the clustershape and push it into the vector
      shape_v_p->push_back(makeClusterShape());
    }

  topoVector.clear();
  topoVector.clear();
  geomVector.clear();
  geomVector.clear();

  return shape_v_p;
}

Member Data Documentation

Definition at line 81 of file PFClusterShapeAlgo.h.

Referenced by covariances(), and makeClusterShape().

Definition at line 81 of file PFClusterShapeAlgo.h.

Referenced by covariances(), and makeClusterShape().

Definition at line 81 of file PFClusterShapeAlgo.h.

Referenced by covariances(), and makeClusterShape().

Definition at line 64 of file PFClusterShapeAlgo.h.

Referenced by find_eMax_e2nd(), getFractionFromDetId(), and makeClusterShapes().

Definition at line 63 of file PFClusterShapeAlgo.h.

Referenced by makeClusterShapes().

Definition at line 65 of file PFClusterShapeAlgo.h.

Referenced by fill5x5Map(), findPFRHIndexFromDetId(), and makeClusterShapes().

double PFClusterShapeAlgo::e2nd_ [private]

Definition at line 79 of file PFClusterShapeAlgo.h.

Referenced by find_eMax_e2nd(), and makeClusterShape().

Definition at line 78 of file PFClusterShapeAlgo.h.

Referenced by find_eMax_e2nd(), and makeClusterShape().

double PFClusterShapeAlgo::e2x2_ [private]

Definition at line 80 of file PFClusterShapeAlgo.h.

Referenced by find_e2x2(), and makeClusterShape().

Definition at line 80 of file PFClusterShapeAlgo.h.

Referenced by find_e2x5Bottom(), and makeClusterShape().

Definition at line 80 of file PFClusterShapeAlgo.h.

Referenced by find_e2x5Left(), and makeClusterShape().

Definition at line 80 of file PFClusterShapeAlgo.h.

Referenced by find_e2x5Right(), and makeClusterShape().

double PFClusterShapeAlgo::e2x5Top_ [private]

Definition at line 80 of file PFClusterShapeAlgo.h.

Referenced by find_e2x5Top(), and makeClusterShape().

double PFClusterShapeAlgo::e3x2_ [private]

Definition at line 80 of file PFClusterShapeAlgo.h.

Referenced by find_e3x2(), and makeClusterShape().

Definition at line 80 of file PFClusterShapeAlgo.h.

Referenced by find_e3x2(), and makeClusterShape().

double PFClusterShapeAlgo::e3x3_ [private]

Definition at line 80 of file PFClusterShapeAlgo.h.

Referenced by find_e3x3(), and makeClusterShape().

double PFClusterShapeAlgo::e4x4_ [private]

Definition at line 80 of file PFClusterShapeAlgo.h.

Referenced by find_e4x4(), and makeClusterShape().

double PFClusterShapeAlgo::e5x5_ [private]

Definition at line 80 of file PFClusterShapeAlgo.h.

Referenced by find_e5x5(), and makeClusterShape().

double PFClusterShapeAlgo::eMax_ [private]

Definition at line 79 of file PFClusterShapeAlgo.h.

Referenced by find_eMax_e2nd(), and makeClusterShape().

Definition at line 76 of file PFClusterShapeAlgo.h.

Referenced by find_e2x2(), and find_e4x4().

Definition at line 78 of file PFClusterShapeAlgo.h.

Referenced by fill5x5Map(), find_eMax_e2nd(), and makeClusterShape().

unsigned int PFClusterShapeAlgo::geomIndex [private]

Definition at line 69 of file PFClusterShapeAlgo.h.

Referenced by makeClusterShapes().

Definition at line 70 of file PFClusterShapeAlgo.h.

Referenced by makeClusterShapes().

Definition at line 72 of file PFClusterShapeAlgo.h.

Referenced by addMapEnergies(), covariances(), fill5x5Map(), and find_e3x2().

Definition at line 73 of file PFClusterShapeAlgo.h.

Referenced by covariances(), and fill5x5Map().

unsigned int PFClusterShapeAlgo::topoIndex [private]

Definition at line 67 of file PFClusterShapeAlgo.h.

Referenced by fill5x5Map(), and makeClusterShapes().

Definition at line 68 of file PFClusterShapeAlgo.h.

Referenced by fill5x5Map(), and makeClusterShapes().

double PFClusterShapeAlgo::totalE_ [private]

Definition at line 74 of file PFClusterShapeAlgo.h.

Referenced by covariances(), and fill5x5Map().

Definition at line 60 of file PFClusterShapeAlgo.h.

Referenced by fill5x5Map(), and PFClusterShapeAlgo().

double PFClusterShapeAlgo::w0_ [private]

Definition at line 61 of file PFClusterShapeAlgo.h.

Referenced by covariances(), and PFClusterShapeAlgo().