In this program we are going to use an individual series using arrays to calculates the Standard Deviation.
Program to Calculate Standard Deviation in Java
public class Main { public static double standard_deviation(double array1[]) { double sum = 0.0, standard_Deviation = 0.0; int len = array1.length; for(double num : array1) { sum += num; } double mean = sum/len; for(double num: array1) { standard_Deviation += Math.pow(num - mean, 2); } return Math.sqrt(standard_Deviation/len); } static double calculate_variance(double array1[]) { // Compute mean (average of elements) int len = array1.length; double sum = 0; for (int i = 0; i < len; i++) sum += array1[i]; double mean = (double)sum/(double)len; // Compute sum squared differences with // mean. double square_Diff = 0; for (int i = 0; i < len; i++) square_Diff += (array1[i] - mean) * (array1[i] - mean); return (double)square_Diff/len; } public static void main(String[] args) { double[] arr = { 30,35,36,40,41,42,55,60,61 }; double Standard_Deviation = standard_deviation(arr); System.out.printf("Standard Deviation is = %.6f", Standard_Deviation); System.out.println(); double variance =calculate_variance(arr); System.out.printf("Varience is = %.6f", variance); } }
Output:-
Standard Deviation is = 147.322775 Varience is = 21704.000000