Question

Must be coded in C#.

10.8 (Rational Numbers) Create a class called Rational for performing arithmetic with fractions. Write an app to test your class. Use integer variables to represent the private instance variables of the class—the numerator and the denominator. Provide a constructor that enables an object of this class to be initialized when it’s declared. The constructor should store the fraction in reduced form. The fraction 2/4 is equivalent to 1/2 and would be stored in the object as 1 in the numerator and 2 in the denominator. Provide a parameterless constructor with default values in case no initializers are provided. Provide public methods that perform each of the following operations (all calculation results should be stored in a reduced form): a) Add two Rational numbers. b) Subtract two Rational numbers. c) Multiply two Rational numbers. d) Divide two Rational numbers. e) Display Rational numbers in the form a/b, where a is the numerator and b is the denominator. f) Display Rational numbers in floating-point format. (Consider providing formatting capabilities that enable the user of the class to specify the number of digits of precision to the right of the decimal point.) Your program should implement exception handling if needed.

Answer 1

Hi. I have answered similar questions before. Here is the completed code for this problem including the code for testing. Comments are included, go through it, learn how things work and let me know if you have any doubts or if you need anything to change. If you are satisfied with the solution, please rate the answer. Thanks

using System;


public class Rational {
    private int numerator;
    private int denominator;

    public Rational(int numerator, int denominator) {
        if (denominator == 0) {
            /**
             * if denominator is 0, throwing an exception.
             */
            throw new InvalidOperationException("Denominator can't be 0");

        }
        /**
         * Finding the GCD
         */
        int gcd = Greatestcommondivisor(numerator, denominator);
        /**
         * removing the GCD from numer..and denom..
         */
        numerator = numerator / gcd;
        denominator = denominator / gcd;
        /**
         * setting values to the variables
         */
        this.numerator = numerator;
        this.denominator = denominator;

        // normalizing
        Normalize();

    }

    public Rational(int numerator):this(numerator, 1) {
        
    }

    public Rational() :this(0, 1){
        
    }

    /**
     * A private method to calculate the greatest common divisor of two numbers
     */
    private int Greatestcommondivisor(int x, int y) {
        if (y == 0)
            return x;
        return Greatestcommondivisor(y, x % y);
    }

    /**
     * method to add a rational number to the current number and returns it
     */
    public Rational Add(Rational b) {
        int num = (this.numerator * b.denominator)
                + (this.denominator * b.numerator);
        int den = this.denominator * b.denominator;
        Rational rational = new Rational(num, den);
        return rational;
    }

    /**
     * method to subtract a rational number from the current number and returns
     * it
     */
    public Rational Sub(Rational b) {
        int num = (this.numerator * b.denominator)
                - (this.denominator * b.numerator);
        int den = this.denominator * b.denominator;
        Rational rational = new Rational(num, den);
        return rational;
    }

    /**
     * method to multiply a rational number to the current number and returns it
     */
    public Rational Mul(Rational b) {
        int num = this.numerator * b.numerator;
        int den = this.denominator * b.denominator;
        Rational rational = new Rational(num, den);
        return rational;
    }

    /**
     * method to divide a rational number from the current number and returns it
     */
    public Rational Div(Rational b) {
        /**
         * Finding the recipocal of second number and multiplying it
         */
        b = b.Reciprocal();
        return Mul(b);
    }

    /**
     * method to return the reciprocal of a rational number
     */
    public Rational Reciprocal() {
        int newNumerator = this.denominator;
        int newDenominator = Math.Abs(this.numerator);
        if (this.numerator < 0) {
            newNumerator = 0 - newNumerator;
        }
        return new Rational(newNumerator, newDenominator);
    }

    public void Normalize() {
        /**
         * if denom is less than 0, making it positive and changing the sign of
         * numerator
         */
        if (denominator < 0) {
            // multiplying numerator and denominator with -1 to swap signs
            denominator *= -1;
            numerator *= -1;
        }
    }

    /**
     * method to return a string representation of a number
     */
    public override String ToString() {
        return numerator + "/" + denominator;
    }
    
    /**
     * method to display rational number in a/b form
     */
    public void DisplayRational(){
        Console.WriteLine(ToString());
    }
    
    /**
     * method to display the rational number in fractional form
     * allowing user to choose precision, or using a default value 2
     */
    public void DisplayAsFraction(int precision=2){
        double fraction=(double)numerator/denominator;
        Console.WriteLine(Math.Round(fraction,precision));
    }
}


//class to test the Rational class and methods
public class RationalTest {
    


    public static void Main(String[] args) {
        //creating two rational numbers and testing the methods
        Rational a = new Rational(2, 3);
        Rational b = new Rational(1, 2);
        Console.WriteLine(a + " + " + b + " = " + a.Add(b));
        Console.WriteLine(a + " - " + b + " = " + a.Sub(b));
        Console.WriteLine(a + " * " + b + " = " + a.Mul(b));
        Console.WriteLine(a + " / " + b + " = " + a.Div(b));

        Console.Write(a+" as Fraction: ");
        //displaying a as fraction with a precision of 4 digits after decimal point
        a.DisplayAsFraction(4);
        
        //waiting for a key press to quit, remove if not necessary.
        Console.WriteLine("\n\n\nPress any key to quit");
        Console.ReadKey();

    }

}

/*OUTPUT*/

2/3 + 1/2 = 7/6

2/3 - 1/2 = 1/6

2/3 * 1/2 = 1/3

2/3 / 1/2 = 4/3

2/3 as Fraction: 0.6667