Fraction

public class fraction {

    private final double limit = 1.0E-6;

    //Input a decimal number and get the fraction
    public String getFraction(double x) {

        double h1 = 1, h2 = 0, k1 = 0, k2 = 1;
        double y = x;

        do {

            double a = Math.floor(y);
            double aux = h1;
            h1 = a*h1+h2;
            h2 = aux;
            aux = k1;
            k1 = a*k1+k2;
            k2 = aux;
            y = 1/(y-a);

        } while (Math.abs(x-h1/k1) > x*limit );

        return ((int) h1) + "/" + ((int) k1);
    }

    //some other methods...

}