GCTAModelRadialPolynom.hpp

Go to the documentation of this file.

/***************************************************************************
 *       GCTAModelRadialPolynom.hpp - Radial Polynom CTA model class       *
 * ----------------------------------------------------------------------- *
 *  copyright (C) 2011-2018 by Juergen Knoedlseder                         *
 * ----------------------------------------------------------------------- *
 *                                                                         *
 *  This program is free software: you can redistribute it and/or modify   *
 *  it under the terms of the GNU General Public License as published by   *
 *  the Free Software Foundation, either version 3 of the License, or      *
 *  (at your option) any later version.                                    *
 *                                                                         *
 *  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          *
 *  GNU General Public License for more details.                           *
 *                                                                         *
 *  You should have received a copy of the GNU General Public License      *
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.  *
 *                                                                         *
 ***************************************************************************/
/**
 * @file GCTAModelRadialPolynom.hpp
 * @brief Radial Polynom model class interface definition
 * @author Juergen Knoedlseder
 */

#ifndef GCTAMODELRADIALPOLYNOM_HPP
#define GCTAMODELRADIALPOLYNOM_HPP

/* __ Includes ___________________________________________________________ */
#include <string>
#include <vector>
#include <cmath>
#include "GMath.hpp"
#include "GModelPar.hpp"
#include "GCTAModelRadial.hpp"
#include "GFunction.hpp"

/* __ Forward declarations _______________________________________________ */
class GRan;
class GXmlElement;
class GCTAObservation;
class GCTAInstDir;


/***********************************************************************//**
 * @class GCTAModelRadialPolynom
 *
 * @brief Radial Polynom CTA model class
 *
 * This class implements the radial function
 * \f[f(\theta) = \sum_{i=0}^m c_i \theta^i\f]
 * where
 * \f$\theta\f$ is the offset angle (in degrees), and
 * \f$c_i\f$ are the polynomial coefficients.
 *
 * This function represents a Polynom in \f$\theta\f$.
 ***************************************************************************/
class GCTAModelRadialPolynom : public GCTAModelRadial {

public:
    // Constructors and destructors
    GCTAModelRadialPolynom(void);
    explicit GCTAModelRadialPolynom(const std::vector<double>& coeffs);
    explicit GCTAModelRadialPolynom(const GXmlElement& xml);
    GCTAModelRadialPolynom(const GCTAModelRadialPolynom& model);
    virtual ~GCTAModelRadialPolynom(void);

    // Operators
    virtual GCTAModelRadialPolynom& operator=(const GCTAModelRadialPolynom& model);

    // Implemented pure virtual methods
    virtual void                    clear(void);
    virtual GCTAModelRadialPolynom* clone(void) const;
    virtual std::string             classname(void) const;
    virtual std::string             type(void) const;
    virtual double                  eval(const double& offset,
                                         const bool& gradients = false) const;
    virtual GCTAInstDir             mc(GRan& ran) const;
    virtual double                  mc_max_value(const GCTAObservation& obs) const;
    virtual double                  omega(void) const;
    virtual void                    read(const GXmlElement& xml);
    virtual void                    write(GXmlElement& xml) const;
    virtual std::string             print(const GChatter& chatter = NORMAL) const;

    // Other methods
    //double coeff(void) const;
    //void   coeff(const double& value);

protected:
    // Protected methods
    void init_members(void);
    void copy_members(const GCTAModelRadialPolynom& model);
    void free_members(void);
    void update_pars(void);

    // Radial integration class (used by omega() method). Note that the
    // integration is done in radians
    class integrand : public GFunction {
    public:
        integrand(const GCTAModelRadialPolynom* model) : m_model(model) { }
        double eval(const double& x) {
            return (std::sin(x)*m_model->eval(x*gammalib::rad2deg));
        }
    private:
        const GCTAModelRadialPolynom* m_model;
    };

    // Protected members
    std::vector<GModelPar> m_coeffs;        //!< Coefficients
};


/***********************************************************************//**
 * @brief Return class name
 *
 * @return String containing the class name ("GCTAModelRadialPolynom").
 ***************************************************************************/
inline
std::string GCTAModelRadialPolynom::classname(void) const
{
    return ("GCTAModelRadialPolynom");
}


/***********************************************************************//**
 * @brief Return model type
 *
 * @return Model type "Polynom".
 ***************************************************************************/
inline
std::string GCTAModelRadialPolynom::type(void) const
{
    return ("Polynom");
}

#endif /* GCTAMODELRADIALPOLYNOM_HPP */