integral.hpp

/*
 Copyright (C) 2007 François du Vignaud
 
 This file is part of QuantLib, a free-software/open-source library
 for financial quantitative analysts and developers - http://quantlib.org/
 
 QuantLib is free software: you can redistribute it and/or modify it
 under the terms of the QuantLib license.  You should have received a
 copy of the license along with this program; if not, please email
 <quantlib-dev@lists.sf.net>. The license is also available online at
 <http://quantlib.org/license.shtml>.
 
 This program is distributed in the hope that it will be useful, but WITHOUT
 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 FOR A PARTICULAR PURPOSE.  See the license for more details.
*/
 
#ifndef quantlib_math_integrator_hpp
#define quantlib_math_integrator_hpp
 
#include <ql/types.hpp>
#include <ql/functional.hpp>
 
namespace QuantLib {
 
    class Integrator{
      public:
        Integrator(Real absoluteAccuracy,
                   Size maxEvaluations);
        virtual ~Integrator() = default;
 
        Real operator()(const ext::function<Real (Real)>& f,
                        Real a,
                        Real b) const;
 
 
        void setAbsoluteAccuracy(Real);
        void setMaxEvaluations(Size);
 
 
        Real absoluteAccuracy() const;
        Size maxEvaluations() const;
 
        Real absoluteError() const ;
 
        Size numberOfEvaluations() const;
 
        virtual bool integrationSuccess() const;
 
      protected:
        virtual Real integrate(const ext::function<Real (Real)>& f,
                               Real a,
                               Real b) const = 0;
        void setAbsoluteError(Real error) const;
        void setNumberOfEvaluations(Size evaluations) const;
        void increaseNumberOfEvaluations(Size increase) const;
      private:
        Real absoluteAccuracy_;
        mutable Real absoluteError_;
        Size maxEvaluations_;
        mutable Size evaluations_;
    };
 
}
 
 
#endif