Identity Matrix Check

This program checks if a matrix is an identity matrix.

Problem Statement

Write a Java program to check whether a 3x3 matrix is an identity matrix.

Source Code

1 public class IdentityMatrixCheck {
2 public static void main(String[] args) {
3 int[][] A = {{1,0,0},{0,1,0},{0,0,1}};
4 boolean identity=true;
5 for(int i=0;i<3;i++){
6 for(int j=0;j<3;j++){
7 if(i==j && A[i][j]!=1) identity=false;
8 else if(i!=j && A[i][j]!=0) identity=false;
9 }
10 }
11 if(identity) System.out.println("Matrix is identity");
12 else System.out.println("Matrix is not identity");
13 }
14 }

Program Output

Matrix is identity

Explanation

An identity matrix has 1s on the main diagonal and 0s elsewhere, so the nested loops check each element against this rule and set a flag to false on any violation, demonstrating identity matrix validation.

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