MaxCmp.h

// -*- C++ -*-
//
// MaxCmp.h is a part of ThePEG - Toolkit for HEP Event Generation
// Copyright (C) 1999-2019 Leif Lonnblad
//
// ThePEG is licenced under version 3 of the GPL, see COPYING for details.
// Please respect the MCnet academic guidelines, see GUIDELINES for details.
//
#ifndef THEPEG_MaxCmp_H
#define THEPEG_MaxCmp_H
//
// This is the declaration of the MaxCmp class.
//
 
#include <functional>
 
namespace ThePEG {
 
template <typename T = double, typename Indx = int, typename Cmp = std::greater<T> >
class MaxCmp {
 
public:
 
  MaxCmp() : init(false), max(T()), indx(Indx()) {}
 
  MaxCmp(const T & t, Indx in = Indx()) : init(true), max(t), indx(in) {}
 
public:
 
  bool operator()(const T & t, Indx i = Indx())
  {
    if ( !init || cmp(t, max) ) {
      max = t;
      init = true;
      indx = i;
      return true;
    }
    return false;
  }
 
  operator const T & () const { return value(); }
 
  const T & value() const { return max; }
 
  Indx index() const {
    return indx;
  }
 
  bool operator!() const {
    return !init;
  }
 
private:
 
  bool init;
 
  T max;
 
  Indx indx;
 
  Cmp cmp;
 
};
 
template <typename T, typename Indx = int>
class MinCmp: public MaxCmp<T, Indx, less<T> > {
 
public:
 
  MinCmp() {}
  
  MinCmp(const T & t, Indx in = Indx()) : MaxCmp<T, Indx, less<T> >(t, in) {}
  
};
 
}
 
#endif /* THEPEG_MaxCmp_H */