Newton-Raphson

package metodenumerik;

/**
 * @author Kelompok3_RK_3IA14
 **/
public class NewtonRaphson {

    public static void main(String[] args) {
        float x = 100;
        float x_sebelum = 9999;
        float selisih = x_sebelum - x;
        float error = (float) 0;
        String prefix1 = "X";
        String prefix2 = "Selisih";
        String format = "%-15s%s%n";

        System.out.printf(format, prefix1, " | " + prefix2);
        System.out.println("------------------------------");
        System.out.printf(format, x, " | " + selisih);

        while(Math.abs(selisih) > error){

            x_sebelum = x;
            x = x_sebelum - (fungsi(x) / turunanFungsi(x));
            selisih = x_sebelum - x;
            System.out.printf(format, x, " | " + selisih);
        }
            String prefix3 = "Akar Persamaan";
            String prefix4 = "Error";
            float absolute = Math.abs(selisih);
            System.out.println("------------------------------");
            System.out.printf(format, prefix3, " : " + x);
            System.out.printf(format, prefix4, " : " + absolute);

    }

     public static float fungsi(float x){
        //fungsi ini bisa diganti dengan fungsi apa pun
        float y = (x * x)-(7 * x)- 7;
        return y;
    }
      public static float turunanFungsi(float x){
        //fungsi ini bisa diganti dengan fungsi apa pun
        float y = (2 * x) - 7;
        return y;
    }

}