SimplifyNumerical.h

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#ifndef PhysicsTools_Utilities_SimplifyNumerical_h
#define PhysicsTools_Utilities_SimplifyNumerical_h
#include "PhysicsTools/Utilities/interface/Fraction.h"
#include "PhysicsTools/Utilities/interface/Numerical.h"
#include "PhysicsTools/Utilities/interface/Operations.h"

namespace funct {

  template <int n, int m>
  struct Sum<Numerical<n>, Numerical<m> > {
    typedef Numerical<n + m> type;
    inline static type combine(const Numerical<n>&, const Numerical<m>&) { return type(); }
  };

  template <int n, int m>
  struct Difference<Numerical<n>, Numerical<m> > {
    typedef Numerical<n - m> type;
    inline static type combine(const Numerical<n>&, const Numerical<m>&) { return type(); }
  };

  template <int n>
  struct Minus<Numerical<n> > {
    typedef Numerical<-n> type;
    inline static type operate(const Numerical<n>&) { return type(); }
  };

  template <int n, int m>
  struct Product<Numerical<n>, Numerical<m> > {
    typedef Numerical<n * m> type;
    inline static type combine(const Numerical<n>&, const Numerical<m>&) { return type(); }
  };

  template <int n>
  struct Ratio<Numerical<n>, Numerical<1> > {
    typedef Numerical<n> type;
    inline static type combine(const Numerical<n>&, const Numerical<1>&) { return type(); }
  };

  // n ^ m = n * n ^ ( m - 1 )
  template <int n, int m, bool posM = (m > 0)>
  struct NumPower {
    typedef Numerical<n * NumPower<n, m - 1>::type::value> type;
    inline static type combine(const Numerical<n>&, const Numerical<m>&) { return type(); }
  };

  // 1 ^ m = 1
  template <int m, bool posM>
  struct NumPower<1, m, posM> {
    typedef Numerical<1> type;
    inline static type combine(const Numerical<1>&, const Numerical<m>&) { return type(); }
  };

  // n ^ 1 = n
  template <int n>
  struct NumPower<n, 1, true> {
    typedef Numerical<n> type;
    inline static type combine(const Numerical<n>&, const Numerical<1>&) { return type(); }
  };

  // n ^ 0 = 1
  template <int n>
  struct NumPower<n, 0, true> {
    typedef Numerical<1> type;
    inline static type combine(const Numerical<n>&, const Numerical<0>&) { return type(); }
  };

  // n ^ (-m) = 1 / n ^ m
  template <int n, int m>
  struct NumPower<n, m, false> {
    typedef typename Fraction<1, NumPower<n, -m>::type::value>::type type;
    inline static type combine(const Numerical<n>&, const Numerical<m>&) { return type(); }
  };

  template <int n, int m>
  struct Power<Numerical<n>, Numerical<m> > : public NumPower<n, m> {};

}  // namespace funct

#endif