Finding the standard deviation of all elements in an array

Hint:

double[] array = {2.5, 3.7, 4.1, 2.9, 5.2, 3.8};

sum = 0;

mean = sum / array.length;

squaredDiffSum += Math.pow(num – mean, 2);

double variance = squaredDiffSum / array.length;

double standardDeviation = Math.sqrt(variance);

Here’s a Java program that calculates the standard deviation of all elements in an array:

import java.util.Scanner;


   public class StandardDeviation {

    public static void main(String[] args) {

        Scanner scanner = new Scanner(System.in);

        // Read the size of the array

        System.out.print("Enter the size of the array: ");

        int size = scanner.nextInt();

        // Create the array

        double[] array = new double[size];

        // Read the array elements

        System.out.println("Enter the elements of the array:");

        for (int i = 0; i < size; i++) {

            System.out.print("Element " + (i + 1) + ": ");

            array[i] = scanner.nextDouble();

        }

        // Calculate the mean

        double sum = 0;

        for (int i = 0; i < size; i++) {

            sum += array[i];

        }

        double mean = sum / size;

       
        // Calculate the sum of squared differences

        double squaredDifferencesSum = 0;

        for (int i = 0; i < size; i++) {

            double difference = array[i] - mean;

            squaredDifferencesSum += difference * difference;

        }

        // Calculate the variance

        double variance = squaredDifferencesSum / size;

       
        // Calculate the standard deviation

        double standardDeviation = Math.sqrt(variance);

        // Print the result

        System.out.println("The standard deviation of the elements is: " + standardDeviation);
    }

}

To use this program, you can simply copy the code into a Java file (e.g., `StandardDeviation.java`) and compile/run it using a Java compiler. The program prompts you to enter the size of the array and the elements of the array, and it then calculates and displays the standard deviation of the elements.