QuadSolv.java Source code

Introduction

Here is the source code for QuadSolv.java

Source

/*
Java Programming for Engineers
Julio Sanchez
Maria P. Canton
    
    
ISBN: 0849308100
Publisher: CRC Press
*/

// Java for Engineers
//Filename: QuadSolv
//Reference: Chapter 24
//Description:
//         Applying the quadratic formula
//Requires:
//         Keyin class in current directory

strictfp class QuadSolv {
    public static void main(String[] args) {

        double a, b, c, discr, root1, root2;

        // Apllying the quadratic formula
        // Obtain sides from user
        System.out.println("Applying the quadratic formula");
        a = 1d;
        b = 2d;
        c = 3d;

        // Solve the discriminant (SQRT (b^2 - 4ac)
        discr = Math.sqrt((b * b) - (4 * a * c));
        System.out.println("Discriminant = " + discr);
        // Determine number of roots
        // if discr > 0 equation has 2 real roots
        // if discr == 0 equation has a repeated real root
        // if discr < 0 equation has imaginary roots
        // if discr is NaN equation has no roots

        // Test for NaN
        if (Double.isNaN(discr))
            System.out.println("Equation has no roots");

        if (discr > 0) {
            System.out.println("Equation has 2 roots");
            root1 = (-b + discr) / 2 * a;
            root2 = (-b - discr) / 2 * a;
            System.out.println("First root = " + root1);
            System.out.println("Second roor = " + root2);
        }

        if (discr == 0) {
            System.out.println("Equation has 1 root");
            root1 = (-b + discr) / 2 * a;
            System.out.println("Root = " + root1);
        }

        if (discr < 0)
            System.out.println("Equation has imaginary roots");

    }
}