HW5.21

 1 import java.util.Scanner;
 2
 3 public class Solution
 4 {
 5     public static void main(String[] args)
 6     {
 7         Scanner input = new Scanner(System.in);
 8         double[] array = new double[10];
 9
10         System.out.print("Enter 10 numbers: ");
11         for(int i = 0; i < array.length; i++)
12             array[i] = input.nextDouble();
13
14         input.close();
15
16         System.out.println("The mean is " + getAverage(array));
17         System.out.println("The standard deviation is " + getStandardDeviation(array));
18     }
19
20     public static double getAverage(double[] array)
21     {
22         double sum = 0;
23         for(int i = 0; i < array.length; i++)
24             sum += array[i];
25         double average = sum / array.length;
26         return average;
27     }
28
29     public static double getStandardDeviation(double[] array)
30     {
31         double sum1 = 0;
32         double sum2 = 0;
33         for(int i = 0; i < array.length; i++)
34         {
35             sum1 += array[i] * array[i];
36             sum2 += array[i];
37         }
38         double standardDeviation = Math.sqrt((sum1 - sum2 * sum2 / array.length) / (array.length - 1));
39         return standardDeviation;
40     }
41 }