//
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//
//
//
// class G4HarmonicPolMagField
//
// Class description:
//
// Class describing magnetic field parametrised by harmonic polynom up to
// 3rd order. The function MagneticField(yTrack,B) calculates the magnetic
// field induction vector B for the trajectory point yTrack according to
// formula given in:
//   M.Metcalf, Analysis of the SFM Field,
//              OM Development Note AP-10 (revised), 1974

// History:
// 3.2.97 - V.Grichine, created.
// --------------------------------------------------------------------

#ifndef G4HARMONICPOLMAGFIELD_HH
#define G4HARMONICPOLMAGFIELD_HH

#include "G4MagneticField.hh"

class G4HarmonicPolMagField : public G4MagneticField
{
  public:  // with description
                       
    G4HarmonicPolMagField();
   ~G4HarmonicPolMagField();
     
    void GetFieldValue(const G4double yTrack[] ,
                             G4double B[]      ) const  ;
    G4HarmonicPolMagField* Clone() const;
};

#endif
