/// \file NewtornRaphson.cpp
/// This is a demonstration of how to use NewtonRaphson.h<br />
/// to compile:  g++ -I. -lm NewtonRaphson.cpp<br />
/// description: this test the algorithm in 3 situations:<br />
///    1) calculating df at bouth points, to find the average df, for each iteration, with no boundaries <br />
///    2) calculating d2f to get second order approximation at each iteration, with no boundaries<br />
///    3) calculating d2f to get second order approximation at each iteration, and a boundary solution<br />

/***************************************************************************
 *   Copyright (C) 2009 by Clark Sims                                      *
 *   http://AcumenSoftwareInc.com/WhoWeAre/Clark_Sims.html                 *
 *   ClarkSims@AcumenSoftwareInc.com                                       *
 *                                                                         *
 *   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 2 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, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/

#include "NewtonRaphson.h"
#include <math.h>

/// \brief This is a functor which encapsulates the function: exp(x) - offset.  The function variable is x. Offset is a hidden variable. This class is used to demonstrate the NewtonRaphsonSolve0< functor, real > template class, in the test file NewtonRaphson.cpp
class Newton_functor {
public:
  /// the hidden variable for class Newton_functor, which makes this class a functor, as opposed to a group of function pointers
  double _offset;
  
  /// the creator for Newton_functor which assigns the hidden variable offset
  Newton_functor( double offset) : _offset(offset) { }

  /// the function to be solved
  double f( double x) {
    return exp( x) - _offset;
  }
  
  /// the derivative of the function to be solved
  double f_prime( double x) {
    return exp( x);
  }
};

int main() {
  Newton_functor sf( 5);

  {
    NewtonRaphsonSolve0< Newton_functor, double > foobar( 1.2, 1e-8, true, 100, sf, &Newton_functor::f, &Newton_functor::f_prime);

    foobar.do_iteration( true);

    foobar.set_d2f( &Newton_functor::f_prime);

    foobar.do_iteration( true);

    foobar.set_check_boundary( true);
    foobar.set_max_x( 1.6);

    foobar.do_iteration( true);
  }

  sf._offset = 0;
  {
    NewtonRaphsonSolve0< Newton_functor, double > foobar( 1.2, 1e-8, true, 100, sf, &Newton_functor::f, &Newton_functor::f_prime, 0, 5.0);

    foobar.do_iteration( true);
  }

  return 0;
}