///MAIN.CPP///

///ATTENTION ROOTFINDER.CPP MODIF POUR FCT 2 VARIABLES !!

#include <iostream>
#include "extremumFinder.h"
#include "rootFinder.h"
#include <cmath>
#include <fstream>

using namespace std;

double f(double x,double y)
{
  double a = 0.54533;
  return pow(pow(x,2)+pow(y+a,2)-1,3)-pow(x,2)*pow(y+a,3);
}

int main()
{
    ofstream retour1 ("roots1.txt",ios::app);
    ofstream retour2 ("roots2.txt",ios::app);
    if (retour1)
    {
         for (double x=-1.139;x<1.139;x=x+0.004556)
        retour1 << x << ";" << getRoot_bmethod(f,x,-2, 0, pow(10,-3))<< endl;
    cout << "Fichier roots1.txt cree" << endl;
    }
    else
        cout << "ERREUR FICHIER";
    if (retour2)
    {
         for (double x=-1.139;x<1.139;x=x+0.004556)
        retour2 << x << ";" << getRoot_bmethod(f,x,0, 1, pow(10,-3))<< endl;
    cout << "Fichier roots2.txt cree" << endl;
    }
    else
        cout << "ERREUR FICHIER";
}

///ROOTFINDER.CPP///


#include <iostream>
#include "rootFinder.h"
#include <cmath>

using namespace std;

double getRoot_bmethod(double (*f)(double,double),double x, double a, double b, double eps)
{
    double c=(b+a)/2;
    if(f(x,a)*f(x,b)>0) ///Si pas de zéro, renvoie "pas de zéro"
        return NAN;
    else if (fabs(f(x,a))<eps) ///Si a est le zéro
        return a;
    else if (fabs(f(x,b))<eps) ///Si b est le zéro
        return b;
    else if (fabs(f(x,c))<eps) ///Si c est direct le zéro
        return c;
    else ///Si au moins un zéro
        do
        {
            c=(b+a)/2;
             if (f(x,c)*f(x,b)>0)
                b=c;
            else
                a=c;
        }
        while (fabs(a-b)>eps);
    return c;
}