Java Variance variance(double[] array)

Description

Returns variance among values in array

License

Open Source License

Parameter

Parameter	Description
array	A double array

Return

returns variance among elements of array

Declaration

public static double variance(double[] array) 

Method Source Code

//package com.java2s;
/*/*from  ww  w.j  ava2  s.  c  o m*/
 *   This program is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

public class Main {
    /**
     * Returns variance among values in array
     * @param array   A {@code double} array 
     * @return returns variance among elements of {@code array}
     */
    public static double variance(double[] array) {
        double sum = 0, mean = 0, var = 0;
        for (double d : array)
            sum += d;
        mean = sum / array.length;
        double temp = 0;
        for (double d : array)
            temp += (mean - d) * (mean - d);
        var = temp / array.length;
        return Math.sqrt(var);
    }
}

Related

1. variance(double[] a)
2. variance(double[] a, int from, int to)
3. variance(double[] arr)
4. variance(double[] arr)
5. variance(double[] array)
6. variance(double[] d)
7. Variance(double[] in, double mean)
8. variance(double[] population)
9. variance(double[] v)