EvtAmplitude.hh

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#ifndef EVT_AMPLITUDE_HH
#define EVT_AMPLITUDE_HH
 
#include "EvtGenBase/EvtComplex.hh"
 
// Complex-valued amplitude
 
template <class T>
class EvtAmplitude {
  public:
    EvtAmplitude() = default;
    EvtAmplitude( const EvtAmplitude& ) = default;
    EvtAmplitude( EvtAmplitude&& ) = default;
    EvtAmplitude& operator=( const EvtAmplitude& ) = default;
    EvtAmplitude& operator=( EvtAmplitude&& ) = default;
    virtual ~EvtAmplitude() = default;
 
    virtual EvtAmplitude<T>* clone() const = 0;
 
    EvtComplex evaluate( const T& p ) const
    {
        EvtComplex ret( 0., 0. );
        if ( p.isValid() )
            ret = amplitude( p );
        return ret;
    }
 
  protected:
    // Derive in subclasses to define amplitude computation
    // for a fully constructed amplitude object.
 
    virtual EvtComplex amplitude( const T& ) const = 0;
};
 
#endif