Java Math Functions with Example

Java provides a built-in Math class, part of the java.lang package, that contains methods for performing basic numeric operations like exponentiation, rounding, trigonometry, square roots, and random number generation. The Math class methods are static, so you can use them without creating an instance of the Math class.

1. Basic Math Methods

Some of the most common mathematical methods in Java include:

• Math.max(): Returns the greater of two values.
• Math.min(): Returns the smaller of two values.
• Math.abs(): Returns the absolute value of a number.
• Math.sqrt(): Returns the square root of a number.
• Math.pow(): Returns the value of one number raised to the power of another.
• Math.round(): Rounds a floating-point value to the nearest integer.

public class Main {
    public static void main(String[] args) {
        int a = 10;
        int b = 20;

        System.out.println("Max: " + Math.max(a, b));       // Outputs 20
        System.out.println("Min: " + Math.min(a, b));       // Outputs 10
        System.out.println("Absolute: " + Math.abs(-10));   // Outputs 10
        System.out.println("Square Root: " + Math.sqrt(25));// Outputs 5.0
        System.out.println("Power: " + Math.pow(2, 3));     // Outputs 8.0
        System.out.println("Round: " + Math.round(7.6));    // Outputs 8
    }
}

2. Random Numbers

Java provides the Math.random() method to generate random numbers. This method returns a random double value between 0.0 (inclusive) and 1.0 (exclusive). To generate a random number within a specific range, you can scale and shift the result of Math.random().

public class Main {
    public static void main(String[] args) {
        // Generate a random number between 0.0 and 1.0
        double randomValue = Math.random();
        System.out.println("Random Value: " + randomValue);

        // Generate a random number between 0 and 100
        int randomInt = (int) (Math.random() * 101);
        System.out.println("Random Integer (0-100): " + randomInt);
    }
}

In this example:

• The first random number is a floating-point number between 0.0 and 1.0.
• The second random number is an integer between 0 and 100.

3. Trigonometric Functions

The Math class includes methods for trigonometric operations such as sine, cosine, and tangent. These methods operate with angles expressed in radians.

• Math.sin(): Returns the sine of the specified angle (in radians).
• Math.cos(): Returns the cosine of the specified angle (in radians).
• Math.tan(): Returns the tangent of the specified angle (in radians).

public class Main {
    public static void main(String[] args) {
        double radians = Math.PI / 4; // 45 degrees in radians

        System.out.println("Sine: " + Math.sin(radians));  // Outputs 0.7071
        System.out.println("Cosine: " + Math.cos(radians));// Outputs 0.7071
        System.out.println("Tangent: " + Math.tan(radians));// Outputs 1.0
    }
}

4. Rounding Functions

The Math class offers several methods to round floating-point numbers to integers:

• Math.ceil(): Rounds a number up to the nearest integer.
• Math.floor(): Rounds a number down to the nearest integer.
• Math.round(): Rounds a number to the nearest integer, using standard rounding rules.

Example:

public class Main {
    public static void main(String[] args) {
        double value = 7.4;

        System.out.println("Ceiling: " + Math.ceil(value)); // Outputs 8.0
        System.out.println("Floor: " + Math.floor(value));  // Outputs 7.0
        System.out.println("Round: " + Math.round(value));  // Outputs 7
    }
}