Natour, O. 11/23/15 Csc-111-D01 Hw 7.11

/*Omar Natour
 * 11/23/2015
 * Csc-111 D01
 * Introduction to Java
 * Problem Number 7.11
 * email [email protected]
 * Problem Desc: Output the mean and standard deviation of values in an array. Currently optimized for use in CMD
*/

import java.util.Scanner;
import java.lang.Math;

public class StandardDev {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);

        //System.out.print("Enter in the length of your array:");  /* Uncomment for use in eclipse console */
        int n = input.nextInt();
        double arr[] = new double[n];

        //System.out.print("Type the values for accending positions in the array starting at position 0. Press Enter after every value."); /* Uncomment for use in eclipse console */
        for (int i = 0; i < n; i++)
            arr[i] = input.nextDouble();

        System.out.println("The mean of your array is " + mean(arr));
        System.out.println("The Standard deviation of your array is " + deviation(arr));
        System.out.println("Your array looks like:");
        outp(arr);
        input.close();
    }

    public static double mean(double[] y) {

        int n = y.length;
        double total = 0;
        double ave = 0;

        for (int i = 0; i < n; i++)
            total += y[i];
        ave = total / n;
        return ave;
    }

    public static double deviation(double[] x) {

        double ave = mean(x);
        double sig = 0;

        for (int i = 0; i < x.length; i++) {
            sig += ((x[i] - ave) * (x[i] - ave)) / x.length;
        }
        return Math.sqrt(sig);
    }

    public static void outp(double[] a) {
        for (int i = 0; i < a.length;) {
            System.out.printf("%8.1f", a[i]);
            i++;
            if (i % 20 == 0)
                System.out.print("\n");
        }
    }
}