C Exercises: Check whether a given matrix is an identity matrix
C Array: Exercise-31 with Solution
Write a program in C to check whether a given matrix is an identity matrix.
Pictorial Presentation:

Sample Solution:
C Code:
#include <stdio.h>
//In a square matrix if all the main diagonal elements are 1's and
//all the remaining elements are 0's is called an Identity Matrix.
void main()
{
int arr1[10][10];
int r1,c1;
int i, j, yn =1;
printf("\n\n Check whether a given matrix is an identity matrix :\n ");
printf("-----------------------------------------------------------\n");
printf("Input number of Rows for the matrix :");
scanf("%d", &r1);
printf("Input number of Columns for the matrix :");
scanf("%d",&c1);
printf("Input elements in the first matrix :\n");
for(i=0;i<r1;i++)
{
for(j=0;j<c1;j++)
{
printf("element - [%d],[%d] : ",i,j);
scanf("%d",&arr1[i][j]);
}
}
printf("The matrix is :\n");
for(i=0;i<r1;i++)
{
for(j=0;j<c1 ;j++)
printf("% 4d",arr1[i][j]);
printf("\n");
}
for(i=0; i<r1; i++)
{
for(j=0; j<c1; j++)
{
if(arr1[i][j] != 1 && arr1[j][i] !=0)
{
yn = 0;
break;
}
}
}
if(yn == 1 )
printf(" The matrix is an identity matrix.\n\n");
else
printf(" The matrix is not an identity matrix.\n\n");
}
Sample Output:
Check whether a given matrix is an identity matrix : ----------------------------------------------------------- Input number of Rows for the matrix :3 Input number of Columns for the matrix :3 Input elements in the first matrix : element - [0],[0] : 1 element - [0],[1] : 0 element - [0],[2] : 0 element - [1],[0] : 0 element - [1],[1] : 1 element - [1],[2] : 0 element - [2],[0] : 0 element - [2],[1] : 0 element - [2],[2] : 1 The matrix is : 1 0 0 0 1 0 0 0 1 The matrix is an identity matrix.
Flowchart :

C Programming Code Editor:
Improve this sample solution and post your code through Disqus.
Previous: Write a program in C to accept two matrices and check whether they are equal.
Next: Write a program in C to find a pair with given sum in the array.
What is the difficulty level of this exercise?
Test your Programming skills with w3resource's quiz.
C Programming: Tips of the Day
C Programming - What is the argument for printf that formats a long?
Put an l (lowercased letter L) directly before the specifier.
unsigned long n; long m; printf("%lu %ld", n, m);
Ref : https://bit.ly/3dIwfkP
- Weekly Trends
- Java Basic Programming Exercises
- SQL Subqueries
- Adventureworks Database Exercises
- C# Sharp Basic Exercises
- SQL COUNT() with distinct
- JavaScript String Exercises
- JavaScript HTML Form Validation
- Java Collection Exercises
- SQL COUNT() function
- SQL Inner Join
- JavaScript functions Exercises
- Python Tutorial
- Python Array Exercises
- SQL Cross Join
- C# Sharp Array Exercises