Calculating Averages in Java Arrays: A Step-by-Step Guide

The Problem Statement

Imagine you have an array numArray that stores a series of floating-point values, and you need to find their average. This is a common scenario in many real-world applications, such as data analysis, scientific computing, and more.

The Solution

To tackle this problem, we’ll employ a Java for-each loop, which provides a concise and efficient way to iterate over the array elements. The following program showcases the solution:

public class AverageCalculator {
    public static void main(String[] args) {
        float[] numArray = {10.5f, 20.7f, 30.1f, 40.9f, 50.3f};
        float sum = 0;
        for (float num : numArray) {
            sum += num;
        }
        float average = sum / numArray.length;
        System.out.printf("The average is %.2f%n", average);
    }
}

Breaking Down the Code

Let’s dissect the code to understand how it works:

• We declare an array numArray to store the floating-point values.
• We initialize a variable sum to zero, which will store the cumulative sum of the array elements.
• The for-each loop iterates over the array, adding each element to the sum variable.
• After the loop, we calculate the average by dividing the sum by the length of the array (numArray.length).
• Finally, we use the printf function to print the average, limiting the decimal points to two using the %.2f format specifier.

The Output

When you run this program, you’ll get the following output:

The average is 30.50

This result is calculated by summing up the array elements (10.5 + 20.7 + 30.1 + 40.9 + 50.3 = 152.5) and then dividing the sum by the array length (5), which gives us an average of 30.50.