package Tutorial7;

public class RootFinder
{
    public static double bisect( MathFunction f, double x1, double x2, double epsilon)
    {
        double m;
        for (m= (x1+x2)/2.0; Math.abs(x1-x2)> epsilon; m= (x1+x2)/2.0)
            if  (f.func(x1)*f.func(m) <= 0.0)
                x2= m;       // Utiliza el subintervalo izquierdo
            else
                x1= m;       // Utiliza el subintervalo derecho
        return m;    
    }
    
    public static double secant(MathFunction f, double x1, double x2, double epsilon)
    {
        double root = x1;
        double y1, y2;
        while (Math.abs(x2 - x1) > epsilon)
             {
                 y1 = f.func(x1);
                 y2 = f.func(x2);
                 root = x1-y1*(x2-x1)/(y2-y1);
                 x1 = x2;
                 x2 = root;
             }
        return root;
    }
    
    public static double regulaFalsi(MathFunction f, double x1, double x2, double epsilon)
    {        
        double y1, y2, root, yroot;
        do {
            y1 = f.func(x1);
            y2 = f.func(x2);
            root = x1-y1*(x2-x1)/(y2-y1);
            yroot = f.func(root);
            if (yroot*y2 < 0.0)
                x1=root;
            else 
                x2=root;
        } while (Math.abs(yroot)>epsilon);
        
        return root;
        
    }
}