Java mean stdDevsOfRows(double[][] matrix, double[] means)

Description

Compute the standard deviations along each row

License

Open Source License

Parameter

Parameter	Description
matrix	a parameter
means	a parameter

Declaration

public static double[] stdDevsOfRows(double[][] matrix, double[] means) 

Method Source Code

//package com.java2s;
/*/*from ww  w  .  j  a va 2  s .  co m*/
 *  Java Information Dynamics Toolkit (JIDT)
 *  Copyright (C) 2012, Joseph T. Lizier
 *  
 *  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 {
    /**
     * Compute the standard deviations along each row
     * 
     * @param matrix
     * @param means
     * @return
     */
    public static double[] stdDevsOfRows(double[][] matrix, double[] means) {
        double[] stds = new double[matrix.length];
        for (int r = 0; r < matrix.length; r++) {
            double sumSqs = 0.0;
            for (int c = 0; c < matrix[r].length; c++) {
                sumSqs += (matrix[r][c] - means[r]) * (matrix[r][c] - means[r]);
            }
            stds[r] = sumSqs / (double) (matrix[r].length - 1);
            stds[r] = Math.sqrt(stds[r]);
        }
        return stds;
    }
}

Related

1. meanWithoutZerosCentered(int[] in, int center, int width)
2. std(double[] a, double mean, boolean isUnbiasedEstimator)
3. std(double[] a, int size, double mean)
4. std(double[] array, double mean)
5. stdDeviation(int[] values, double mean)
6. stdev(final double[] values, final double mean)
7. stdevm(double[] values, double mean)