Symmetric matrix program in java

Let’s learn symmetric matrix program in java.

Symmetric matrix program in java

A square matrix is said to be symmetric if given square matrix is equal to its transpose.

How to tell if a matrix is symmetric?

For a matrix to be symmetric, first it should be a square matrix and second every element at “i”th row and “j”th column should be equal to element at “j”th row and “i”th column.

That is A[i][j] == A[j][i]. Here’s the program to check if the matrix is symmetric or not.

import java.util.Scanner;
public class SymmetricMatrixDemo
{
   public static void main(String[] args)
   {
      Scanner sc = new Scanner(System.in);
      System.out.println("Please enter number of rows - ");
      int row = sc.nextInt();
      System.out.println("Please enter number of columns - ");
      int col = sc.nextInt();
      int symMatrix[][] = new int[row][col];
      System.out.println("Please enter the elements - ");
      for(int x = 0; x < row; x++)
      {
         for(int y = 0; y < col; y++)
         {
            symMatrix[x][y] = sc.nextInt();
         }
      }
      System.out.println("Now printing the input matrix - ");
      for(int x = 0; x < row; x++)
      {
         for(int y = 0; y < col; y++)
         {
            System.out.print(symMatrix[x][y] + "\t");
         }
         System.out.println();
      }
      // check if a matrix is symmetric
      if(row != col)
      {
         System.out.println("It's not a square matrix!!");
      }
      else
      {
         boolean symmetricMatrix = true;
         for(int x = 0; x < row; x++)
         {
            for(int y = 0; y < col; y++)
            {
               if(symMatrix[x][y] != symMatrix[y][x])
               {
                  symmetricMatrix = false;
                  break;
               }
            }
         }
         if(symmetricMatrix)
         {
            System.out.println("It's a symmetric matrix!!");
         }
         else
         {
            System.out.println("It's not a symmetric matrix!!");
         }
      }
      sc.close();
   }
}

Output:

Please enter number of rows – 3
Please enter number of columns – 3
Please enter the elements –
2 4 6 4 1 8 6 8 10
Now printing the input matrix –
2 4 6
4 1 8
6 8 10
It’s a symmetric matrix!!