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//
//
// $Id: $
//
// Helper namespace 'field_utils'
//
// Description:
//    Simple methods to extract vectors from arrays in conventions of
//     the magnetic field integration
//
//    Implementation by Dmitry Sorokin - GSoC 2017
//       Work supported by Google as part of Google Summer of Code 2017.
//    Supervision / code review: John Apostolakis

#ifndef G4FIELD_UTILS_HH
#define G4FIELD_UTILS_HH

#include "G4Types.hh"
#include "G4ThreeVector.hh"

namespace field_utils {

enum class Value3D {
    Position = 0,
    Momentum = 3,
    Spin = 9
};

enum class Value1D {
    KineticEnergy = 6,
    LabTime = 7,
    ProperTime = 8
};

template <typename ArrayType>
G4double getValue(const ArrayType& array, Value1D value);

template <typename ArrayType>
G4double getValue2(const ArrayType& array, Value1D value);

template <typename ArrayType>
G4double getValue(const ArrayType& array, Value3D value);

template <typename ArrayType>
G4double getValue2(const ArrayType& array, Value3D value);

template <typename ArrayType>
G4ThreeVector makeVector(const ArrayType& array, Value3D value);

G4double relativeError(
    const G4double y[],
    const G4double yerr[],
    const G4double hstep,
    const G4double errorTolerance = 1);

} // field_utils

#include "G4FieldUtils.icc"

#endif
