EvtItgAbsFunction.hh

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#ifndef EVTITGABSFUNCTION_HH
#define EVTITGABSFUNCTION_HH

//-------------
// C Headers --
//-------------
extern "C" {
}

// Description:
//      Abstraction of a generic function for use in integration methods elsewhere
//      in this package. (Stolen and modified from the BaBar IntegrationUtils package
//      - author: Phil Strother).

class EvtItgAbsFunction {
  public:
    // Constructors

    EvtItgAbsFunction( double lowerRange, double upperRange );

    // Destructor
    virtual ~EvtItgAbsFunction() = default;

    virtual double value( double x ) const;

    virtual double operator()( double x ) const;

    // Selectors (const)

    inline double upperRange() const { return _upperRange; }
    inline double lowerRange() const { return _lowerRange; }
    inline void getRange( double& lower, double& upper ) const
    {
        lower = _lowerRange;
        upper = _upperRange;
    }
    virtual void setCoeff( int, int, double ) = 0;
    virtual double getCoeff( int, int ) = 0;

  protected:
    virtual double myFunction( double x ) const = 0;
    void setRange( double x1, double x2 )
    {
        _lowerRange = x1;
        _upperRange = x2;
    };

  private:
    double _upperRange;
    double _lowerRange;
};

#endif    // EVTITGABSFUNCTION_HH