Java Programming | Multiplication of matrices using 2d arrays.

This is a tutorial for multiplication of matrices using 2d arrays in java. The program is given below that takes two matrices from user and multiplies them and prints the product. The program is extendable. Go enjoy the program. Lets begin…

Program for multiplication of matrices using 2d arrays in java.

//import Scanner as we require it.
import java.util.Scanner;

// the name of our class its public
public class MatrixMultiply {
	//void main
		public static void main (String[] args)
		{
			//declare int
			int i,j,k,s=0,a[][] = new int[10][10],b[][]= new int[10][10];

			//Declare input as scanner
			Scanner input = new Scanner(System.in);

			//Take input for matrix
			for(i=0;i<3;i++)
			{
				for(j=0;j<3;j++)
				{
					System.out.println("Enter Number :");
					a[i][j] = input.nextInt();
				}
			}

			//Take input for other matrix
			System.out.println("Enter Other Matrix");
			for(i=0;i<3;i++)
			{
				for(j=0;j<3;j++)
				{
					System.out.println("Enter Number :");
					b[i][j] = input.nextInt();
				}
			}

			System.out.println("Product :-");
			//print the product.
			for(i=0;i<3;i++)
			{
				for(j=0;j<3;j++){

					for(k=0;k<3;k++)
						s=s+a[i][k]*b[k][j];

					System.out.print(s+" ");
					s=0;
				}
				System.out.print("\n");
			}
		}
}

Output

Enter Number :
1
Enter Number :
2
Enter Number :
3
Enter Number :
1
Enter Number :
2
Enter Number :
3
Enter Number :
1
Enter Number :
2
Enter Number :
3
Enter Other Matrix
Enter Number :
1
Enter Number :
2
Enter Number :
3
Enter Number :
1
Enter Number :
2
Enter Number :
3
Enter Number :
1
Enter Number :
2
Enter Number :
3
Product :-
6 12 18
6 12 18
6 12 18

How does it work
1. You enter the number.
2. The number is saved in respective array for first matrix.
3. The number is saved in respective array for second matrix.
4. Then numbers are multiplied and printed to form of matrix.

Extending it
The program can be extended by using more numbers and making the matrix more bigger. Go extend it.

Explanation.
1. Import the Scanner.
2. Declare the class as public
3. Add the void main function
4. Declare input as Scanner.
5. Add two for loops.
6. Add system.out.println() function with the message to enter number.
7. Take the inputs and save it in arrays.
8. Take the inputs and save it in other arrays.
9. Add two more loops to print the multiplication of matrix.
10. Add system.out.print() function to print \n to break line.

At the end.
You learnt creating the Java program for Multiplication of matrices using 2d arrays. So now enjoy the program.