Units.h

#ifndef HEPMC_UNITS_H
#define HEPMC_UNITS_H

//--------------------------------------------------------------------------
// Units.h
// Author:  A. Buckley, D. Grellscheid
//
// units used by a GenEvent
// The default units are set by a configure switch at compile time in Units.cc.
//--------------------------------------------------------------------------

#include <iostream>
#include <string>

namespace HepMC {

  namespace Units {

    // Convention: if both types are passed, MomentumUnit always goes first.
    enum MomentumUnit { MEV, GEV };     
    enum LengthUnit   { MM, CM };       
    
    LengthUnit   default_length_unit();         
    MomentumUnit default_momentum_unit();       

    // helper functions
    std::string name( MomentumUnit );   
    std::string name( LengthUnit );     

    double conversion_factor( MomentumUnit from, MomentumUnit to ); 
    double conversion_factor( LengthUnit from, LengthUnit to );

  }     // Units
}       // HepMC

#endif // HEPMC_UNITS_H