Multiplication of two Matrices using Java

Matrix multiplication leads to a new matrix by multiplying 2 matrices. But this is only possible if the columns of the first matrix are equal to the rows of the second matrix. An example of matrix multiplication with square matrices is given as follows.

Example

 Live Demo

public class Example {
   public static void main(String args[]) {
      int n = 3;
      int[][] a = { {5, 2, 3}, {2, 6, 3}, {6, 9, 1} };
      int[][] b = { {2, 7, 5}, {1, 4, 3}, {1, 2, 1} };
      int[][] c = new int[n][n];
      System.out.println("Matrix A:");
      for (int i = 0; i < n; i++) {
         for (int j = 0; j < n; j++) {
            System.out.print(a[i][j] + " ");
         }
         System.out.println();
      }
      System.out.println("Matrix B:");
      for (int i = 0; i < n; i++) {
         for (int j = 0; j < n; j++) {
            System.out.print(b[i][j] + " ");
         }
         System.out.println();
      }
      for (int i = 0; i < n; i++) {
         for (int j = 0; j < n; j++){
            for (int k = 0; k < n; k++) {
               c[i][j] = c[i][j] + a[i][k] * b[k][j];
            }
         }
      }
      System.out.println("The product of two matrices is:");
      for (int i = 0; i < n; i++) {
         for (int j = 0; j < n; j++) {
            System.out.print(c[i][j] + " ");
         }
         System.out.println();
      }
   }
}

Output

Matrix A:
5 2 3
2 6 3
6 9 1
Matrix B:
2 7 5
1 4 3
1 2 1
The product of two matrices is:
15 49 34
13 44 31
22 80 58

Samual Sam

Published on 07-Dec-2018 07:19:21