JetSubStructureUtils::Volatility Class Reference

#include <Volatility.h>

Inheritance diagram for JetSubStructureUtils::Volatility:

Collaboration diagram for JetSubStructureUtils::Volatility:

Public Member Functions
	Volatility (unsigned int num_iterations, double zcut, double dcut_fctr, double exp_min, double exp_max, double rigidity, double truncation_fctr=0.0)
virtual double	result (const fastjet::PseudoJet &jet) const
void	setSeed (unsigned int seed)
virtual TOut	result (const xAOD::Jet &jet) const

Private Attributes
unsigned int	m_num_iterations
double	m_zcut
double	m_dcut_fctr
double	m_exp_min
double	m_exp_max
double	m_rigidity
double	m_truncation_fctr
int	m_seed

Detailed Description

Definition at line 12 of file Volatility.h.

Constructor & Destructor Documentation

Volatility()

JetSubStructureUtils::Volatility::Volatility ( unsigned int num_iterations, double zcut, double dcut_fctr, double exp_min, double exp_max, double rigidity, double truncation_fctr = 0.0 )

inline

Definition at line 14 of file Volatility.h.

                                                         :
        m_num_iterations(num_iterations),
        m_zcut(zcut), m_dcut_fctr(dcut_fctr), m_exp_min(exp_min), m_exp_max(exp_max),
        m_rigidity(rigidity), m_truncation_fctr(truncation_fctr),
        m_seed(-1)
        {};

Member Function Documentation

result() [1/2]

double Volatility::result ( const fastjet::PseudoJet & jet ) const

virtual

Definition at line 11 of file Volatility.cxx.

{
  vector<fastjet::PseudoJet> constit_pseudojets = jet.constituents();
  if(constit_pseudojets.empty()) return -999;
 
  QjetsPlugin qjets_plugin(m_zcut, m_dcut_fctr, m_exp_min, m_exp_max, m_rigidity, m_truncation_fctr);
  fastjet::JetDefinition qjets_def(&qjets_plugin);
 
  unsigned int n = 0;
  double sum_mass = 0, sum_mass2 = 0;
  for(unsigned int i=0; i < m_num_iterations; i++) {
    if(m_seed != -1) { // Seed needs to be different for each run of Qjets, but this has consistent running
      qjets_plugin.SetRandSeed(m_seed + i);
    }
    fastjet::ClusterSequence clust_seq(constit_pseudojets, qjets_def);
    vector<fastjet::PseudoJet> qjets = fastjet::sorted_by_pt(clust_seq.inclusive_jets());
 
    if(qjets.empty()) {
      //cout << "0 jets" << endl;
      continue;
    }
 
    n++;
    sum_mass += qjets[0].m();
    sum_mass2 += qjets[0].m2();
  }
 
  if(n == 0) {
    // Prevent div-0
    return -999;
  }
 
  double rms_dev2 = sum_mass2/n - pow(sum_mass/n, 2.0);
  if(rms_dev2 < 0) {
    // To prevent NaN. Small negative numbers can happen due to floating point inaccuracy
    // when all qjets are same -> i.e. 0 rms
    rms_dev2 = 0;
  }
  
  double rms_dev = sqrt(rms_dev2);
  double volatility = rms_dev / (sum_mass/n);
 
  return volatility;
}

result() [2/2]

virtual TOut JetSubStructureUtils::SubstructureCalculator< TOut >::result ( const xAOD::Jet & jet ) const

inlinevirtual

Reimplemented from JetSubStructureUtils::SubstructureCalculator< double >.

Definition at line 25 of file SubstructureCalculator.h.

                                                    {
        // PS 4/18 master developent
        // std::vector<fastjet::PseudoJet> constit_pseudojets =
        //   jet::JetConstituentFiller::constituentPseudoJets(jet);
 
        std::vector<fastjet::PseudoJet> constit_pseudojets;
        std::transform(jet.getConstituents().begin(),
                       jet.getConstituents().end(),
                       std::back_inserter(constit_pseudojets),
                       [](const auto& c){
                         const xAOD::IParticle* ip = c->rawConstituent();
                         return
                           // fastjet::PseudoJet((c->rawConstituent())->p4());
                           fastjet::PseudoJet(ip->p4());
                       });
 
        fastjet::PseudoJet pjet = fastjet::join(constit_pseudojets);
 
        return result(pjet);
      }

setSeed()

void Volatility::setSeed

(

unsigned int

seed

)

Definition at line 56 of file Volatility.cxx.

{
  m_seed = seed;
}

Member Data Documentation

m_dcut_fctr

double JetSubStructureUtils::Volatility::m_dcut_fctr

private

Definition at line 29 of file Volatility.h.

m_exp_max

double JetSubStructureUtils::Volatility::m_exp_max

private

Definition at line 29 of file Volatility.h.

m_exp_min

double JetSubStructureUtils::Volatility::m_exp_min

private

Definition at line 29 of file Volatility.h.

m_num_iterations

unsigned int JetSubStructureUtils::Volatility::m_num_iterations

private

Definition at line 28 of file Volatility.h.

m_rigidity

double JetSubStructureUtils::Volatility::m_rigidity

private

Definition at line 29 of file Volatility.h.

m_seed

int JetSubStructureUtils::Volatility::m_seed

private

Definition at line 30 of file Volatility.h.

m_truncation_fctr

double JetSubStructureUtils::Volatility::m_truncation_fctr

private

Definition at line 29 of file Volatility.h.

m_zcut

double JetSubStructureUtils::Volatility::m_zcut

private

Definition at line 29 of file Volatility.h.

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The documentation for this class was generated from the following files:

• Volatility.h
• Volatility.cxx