CRNPolynomialRegression.h

Go to the documentation of this file.

/* Copyright 2011-2016 CoReNum, INSA-Lyon, Université Paris Descartes, ENS-Lyon
 * 
 * This file is part of libcrn.
 * 
 * libcrn is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * libcrn 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
 * GNU Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public License
 * along with libcrn.  If not, see <http://www.gnu.org/licenses/>.
 * 
 * file: CRNPolynomialRegression.h
 * \author Yann LEYDIER
 */

#ifndef CRNPolynomialRegression_HEADER
#define CRNPolynomialRegression_HEADER

#include <CRNMath/CRNCartesian2DFunction.h>
#include <CRNGeometry/CRNPoint2DDouble.h>
#include <CRNException.h>

namespace crn
{
    class PolynomialRegression: public crn::Cartesian2DFunction
    {
        public:
            enum class Extrapolation { LINEAR, POLY };

            template<typename Iter> PolynomialRegression(Iter beg, Iter en, size_t dim):
                dimension(dim),
                data(std::distance(beg, en)),
                coefficients(dim + 1),
                extrapolation(Extrapolation::POLY)
            {
                if (dim == 0)
                    throw crn::ExceptionDomain("Null order");
                if (data.size() < dimension)
                    throw crn::ExceptionDimension("There must be more samples than the dimension.");
                size_t cnt = 0;
                for (Iter tmp = beg; tmp != en; ++tmp)
                    data[cnt++] = makePoint(*tmp);
                computeCoeffs();
            }
            PolynomialRegression(const PolynomialRegression&) = default;
            PolynomialRegression(PolynomialRegression&&) = default;
            PolynomialRegression& operator=(const PolynomialRegression&) = default;
            PolynomialRegression& operator=(PolynomialRegression&&) = default;
            virtual ~PolynomialRegression() override {}

            void SetExtrapolationMode(Extrapolation ex) noexcept { extrapolation = ex; }

            void TranslateY(int increment);

            virtual double operator[](double x) const override;
            using Cartesian2DFunction::operator[];

            size_t GetDimension() const noexcept { return dimension; }
            const std::vector<crn::Point2DDouble>& GetData() const noexcept { return data; }
            const std::vector<double>& GetCoefficients() const noexcept { return coefficients; }

        private:
            template<typename T> Point2DDouble makePoint(const crn::Point2D<T> &p)
            { return crn::Point2DDouble(double(p.X), double(p.Y)); }
            template<typename T> Point2DDouble makePoint(const crn::Point2D<T> *p)
            { return crn::Point2DDouble(double(p->X), double(p->Y)); }
            template<typename T, typename Y> Point2DDouble makePoint(const std::pair<T, Y> &p)
            { return crn::Point2DDouble(double(p.first), double(p.second)); }
            void computeCoeffs();

            std::vector<double> coefficients;
            std::vector<crn::Point2DDouble> data; 
            Extrapolation extrapolation;
            size_t dimension;

            CRN_DECLARE_CLASS_CONSTRUCTOR(PolynomialRegression)
    };
    template<> struct IsClonable<PolynomialRegression> : public std::true_type {};

    CRN_ALIAS_SMART_PTR(PolynomialRegression)
}

#endif