Java Program to Find Sum of Matrix Elements

by

In the previous article, we have discussed Java Program to Print 3*3 Matrix

In this article we are going to see how we can write a program to calculate the sum of matrix elements in JAVA language.

Java Program to Find Sum of Matrix Elements

A 3*3 Matrix is having 3 rows and 3 columns where this 3*3 represents the dimension of the matrix. Means there are 3*3 i.e. total 9 elements in a 3*3 Matrix.

Let’s understand it in more simpler way.

                   | A00   A01   A02 |
Matrix A =  | A10   A11   A12 |
                   | A20   A21   A22 | 3*3
  • Matrix A represents a 3*3 matrix.
  • ‘A‘ represents the matrix element
  • ‘Aij‘ represents the matrix element at it’s matrix position/index.
  • ‘i‘ represents the row index
  • ‘j‘ represents the column index
  • Means A00=Aij  where i=0 and j=0,  A01=aij where i=0 and j=1 and like this.
  • Here we have started row value from 0 and column value from 0.

Let’s see different ways to find sum of matrix elements.

Method-1: Java Program to Find Sum of Matrix Elements By Static Initialization of Array Elements

Approach:

  • Initialize and declare an array of size 3×3 with elements.
  • Use two for loops to iterate the rows and columns and then add each element to the sum variable.
  • Print the sum.

Program:

import java.util.Scanner;

public class Matrix
{
    public static void main(String args[])
    {
        //Scanner class to take input
        Scanner scan = new Scanner(System.in);

        // Initializing the 3X3 matrix i.e. 2D array
        int arr[][] = {{10,20,30},{40,50,60},{70,80,90}};
        int row, col, sum = 0;
        
        System.out.print("The matrix elements are : ");
        // Loop to print the elements
        for(row=0;row<3;row++)
        {
            // Used for formatting
            System.out.print("\n");
            for(col=0;col<3;col++)
            {
                System.out.print(arr[row][col]+" ");
            }
        }

        // Loop to take the sum of elements
        for(row=0;row<3;row++)
            for(col=0;col<3;col++)
                sum+=arr[row][col];

        System.out.print("\nThe sum of all the matrix elements is : "+sum);
    }
}

Output:

The matrix elements are : 
10 20 30 
40 50 60 
70 80 90 
The sum of all the matrix elements is : 450

Method-2: Java Program to Find Sum of Matrix Elements By Dynamic Initialization of Array Elements

Approach:

  • Initialize an array of size 3×3.
  • Ask the user for input.
  • Use two for loops to iterate the rows and columns and input the array elements.
  • Similarly use two for loops to add each element and store in sum variable.
  • Print the sum.

Program:

import java.util.Scanner;
public class matrix{
    public static void main(String args[])
    {
        //Scanner class to take input
        Scanner scan = new Scanner(System.in);

        // Initializing the 3X3 matrix i.e. 2D array
        int arr[][] = new int[3][3], sum = 0;

        System.out.println("Enter the 3x3 matrix elements : ");
        int row, col;
        // Loop to take user input
        for(row=0;row<3;row++)
            for(col=0;col<3;col++)
                arr[row][col] = scan.nextInt();
                
       System.out.print("The matrix elements are : "); 
       // Loop to print the elements 
       for(row=0;row<3;row++) 
       { 
           // Used for formatting 
           System.out.print("\n"); 
           for(col=0;col<3;col++) 
           { 
               System.out.print(arr[row][col]+" "); 
           } 
       }
       
       System.out.print("\n"); 
        
        // Loop to take the sum of elements
        for(row=0;row<3;row++)
            for(col=0;col<3;col++)
                sum+=arr[row][col];

        System.out.println("The sum of all the matrix elements is : "+sum);
    }
}

Output:

Enter the 3x3 matrix elements : 1 2 3 4 5 6 7 8 9
The matrix elements are : 
1 2 3 
4 5 6 
7 8 9 
The sum of all the matrix elements is : 45

Have you mastered basic programming topics of java and looking forward to mastering advanced topics in a java programming language? Go with these ultimate Advanced java programs examples with output & achieve your goal in improving java coding skills.

Related Java Programs: