include/EvtGenModels/EvtItgAbsFunction.hh

0001
0002 /***********************************************************************
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0020
0021 #ifndef EVTITGABSFUNCTION_HH
0022 #define EVTITGABSFUNCTION_HH
0023
0024 //-------------
0025 // C Headers --
0026 //-------------
0027 extern "C" {
0028 }
0029
0030 // Description:
0031 //      Abstraction of a generic function for use in integration methods elsewhere
0032 //      in this package. (Stolen and modified from the BaBar IntegrationUtils package
0033 //      - author: Phil Strother).
0034
0035 class EvtItgAbsFunction {
0036   public:
0037     // Constructors
0038
0039     EvtItgAbsFunction( double lowerRange, double upperRange );
0040
0041     // Destructor
0042     virtual ~EvtItgAbsFunction() = default;
0043
0044     virtual double value( double x ) const;
0045
0046     virtual double operator()( double x ) const;
0047
0048     // Selectors (const)
0049
0050     inline double upperRange() const { return _upperRange; }
0051     inline double lowerRange() const { return _lowerRange; }
0052     inline void getRange( double& lower, double& upper ) const
0053     {
0054         lower = _lowerRange;
0055         upper = _upperRange;
0056     }
0057     virtual void setCoeff( int, int, double ) = 0;
0058     virtual double getCoeff( int, int ) = 0;
0059
0060   protected:
0061     virtual double myFunction( double x ) const = 0;
0062     void setRange( double x1, double x2 )
0063     {
0064         _lowerRange = x1;
0065         _upperRange = x2;
0066     };
0067
0068   private:
0069     double _upperRange;
0070     double _lowerRange;
0071 };
0072
0073 #endif    // EVTITGABSFUNCTION_HH