Java Matrix Multiply multiply(double[][] p, double[][] q)

Description

Multiply two matrices

License

Open Source License

Parameter

Parameter	Description
p	A 3x3 matrix
q	A 3x3 matrix

Declaration

public static double[][] multiply(double[][] p, double[][] q) 

Method Source Code

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

public class Main {
    /**//from  w  ww .  j ava  2 s.  com
     * Multiply two matrices
     * 
     * @param p A 3x3 matrix
     * @param q A 3x3 matrix
     * @return
     */
    public static double[][] multiply(double[][] p, double[][] q) {

        double[][] m = new double[3][3];

        for (int i = 0; i < 3; i++) {
            for (int j = 0; j < 3; j++) {
                m[i][j] = 0;
                for (int k = 0; k < 3; k++) {
                    m[i][j] += p[i][k] * q[k][j];
                }
            }
        }

        return m;
    }

    /**
     * Multiply a vector by a matrix
     * 
     * @param m A 3x3 matrix
     * @param v A 3x1 vector
     * @return
     */
    public static double[] multiply(double[][] m, double[] v) {

        double[] u = new double[3];

        for (int i = 0; i < 3; i++) {
            u[i] = 0;
            for (int j = 0; j < 3; j++) {
                u[i] += m[i][j] * v[j];
            }
        }

        return u;
    }
}

Related

1. multiply(double[][] a, double[][] b)
2. multiply(double[][] a, double[][] x)
3. multiply(double[][] dest, double[][] a, double[][] b)
4. multiply(double[][] m, double[] x)
5. multiply(double[][] m1, double[][] m2)
6. multiply(double[][] x, double[][] y)
7. multiply(final double[][] A, final double[][] B)
8. multiply(float[][] a, float num)
9. multiply(float[][] a, float[][] b)