include/EvtGenModels/EvtItgAbsIntegrator.hh

0001
0002 /***********************************************************************
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0020
0021 #ifndef EVTITGABSINTEGRATOR_HH
0022 #define EVTITGABSINTEGRATOR_HH
0023
0024 #include "EvtGenModels/EvtItgAbsFunction.hh"
0025
0026 // Description:
0027 //      Abstraction of a generic integrator (Stolen and modified from
0028 //      the BaBar IntegrationUtils package - author: Phil Strother).
0029
0030 class EvtItgAbsIntegrator {
0031   public:
0032     EvtItgAbsIntegrator( const EvtItgAbsFunction& );
0033
0034     virtual ~EvtItgAbsIntegrator() = default;
0035
0036     double evaluate( double lower, double upper ) const;
0037
0038     double normalisation() const;
0039
0040   protected:
0041     double trapezoid( double lower, double higher, int n, double& result ) const;
0042
0043     virtual double evaluateIt( double lower, double higher ) const = 0;
0044
0045     double myFunction( double x ) const { return _myFunction( x ); }
0046
0047   private:
0048     const EvtItgAbsFunction& _myFunction;
0049
0050     void boundsCheck( double&, double& ) const;
0051
0052     // Note: if your class needs a copy constructor or an assignment operator,
0053     //  make one of the following public and implement it.
0054     EvtItgAbsIntegrator();
0055     //EvtItgAbsIntegrator( const EvtItgAbsIntegrator& );                // Copy Constructor
0056     //EvtItgAbsIntegrator& operator= ( const EvtItgAbsIntegrator& );    // Assignment op
0057 };
0058
0059 #endif    // EVTITGABSINTEGRATOR_HH