Java Array Normalize norm(double[] vector, int n)

Description

This method takes the Ln vector norm of the vector according to the formula: Norm = [E(i=0 to vector.length) |vector[i]|^n]^(1.0/n)

License

Open Source License

Parameter

Parameter	Description
vector	a parameter
n	a parameter

Return

the vector norm of the given vector to the nth degree

Declaration

public static double norm(double[] vector, int n)

Method Source Code

//package com.java2s;
//License from project: Open Source License 

public class Main {
    /**/*from  ww w  .ja v  a  2  s  .  c  o  m*/
     * This method takes the Ln vector norm of the vector according to the formula:
     * Norm = [E(i=0 to vector.length) |vector[i]|^n]^(1.0/n)
     * @param vector
     * @param n
     * @return the vector norm of the given vector to the nth degree
     */
    public static double norm(double[] vector, int n) {
        double norm = 0.0;
        //Go through each component
        for (int i = 0; i < vector.length; ++i) {
            double inner = 1.0;
            double comp = Math.abs(vector[i]);
            //Get the appropriate power of the component
            for (int dim = 0; dim < n; ++dim)
                inner *= comp;
            //Add the |comp|^n to our sum
            norm += inner;
        }
        //Take the appropriate root, don't waste the method call if
        //n is 1.
        if (n != 1)
            norm = Math.pow(norm, 1.0 / n);
        return norm;
    }
}