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SortUtil.h

#ifndef ATHENA_UTIL_SORT_UTIL_H
#define ATHENA_UTIL_SORT_UTIL_H

#include "particle/Particle.h"
#include <cmath>

//     [0]      [n-1]
// Pt  High --> Low
class High2LowByParticleClassPt
{
public:
  bool operator () (const Particle *t1, const Particle *t2) const {
    return (t1->pt() > t2->pt());
  }
};

// Pt  Low --> High
class Low2HighByParticleClassPt
{
public:
  bool operator () (const Particle *t1, const Particle *t2) const {
    return (t1->pt() < t2->pt());
  }
};

// P  High --> Low
class High2LowByParticleClassP
{
public:
  bool operator () (const Particle *t1, const Particle *t2) const {
    return (t1->p().vect().mag() > t2->p().vect().mag());
  }
};

// P  Low --> High
class Low2HighByParticleClassP
{
public:
  bool operator () (const Particle *t1, const Particle *t2) const {
    return (t1->p().vect().mag() < t2->p().vect().mag());
  }
};

// Energy  High --> Low
class High2LowByParticleClassEnergy
{
public:
  bool operator () (const Particle *t1, const Particle *t2) const {
    return (t1->e() > t2->e());
  }
};

// Energy  Low --> High
class Low2HighByParticleClassEnergy
{
public:
  bool operator () (const Particle *t1, const Particle *t2) const {
    return (t1->e() < t2->e());
  }
};

// Eta  Low --> High
class Low2HighByParticleClassEta
{
public:
  bool operator () (const Particle *t1, const Particle *t2) const {
    return (t1->eta() < t2->eta());
  }
};

// Eta  High --> Low
class High2LowByParticleClassEta
{
public:
  bool operator () (const Particle *t1, const Particle *t2) const {
    return (t1->eta() > t2->eta());
  }
};

// |Eta|  Low --> High
class Low2HighByParticleClassAbsEta
{
public:
  bool operator () (const Particle *t1, const Particle *t2) const {
    return (fabs(t1->eta()) < fabs(t2->eta()));
  }
};

// |Eta|  High --> Low
class High2LowByParticleClassAbsEta
{
public:
  bool operator () (const Particle *t1, const Particle *t2) const {
    return (fabs(t1->eta()) > fabs(t2->eta()));
  }
};

#endif // ATHENA_UTIL_SORT_UTIL_H

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