Program 289: Program to Check whether given Matrix is Orthogonal or not

Program 289: Program to Check whether given Matrix is Orthogonal or not

#include<stdio.h>
main()
{
 int i,j,k,size,flag=1;
 printf("Enter size of square matrix i.e 3 for 3x3 and 4 for 4x4 etc\n");
 scanf("%d",&size);
 int a[size][size],temp[size][size],identityCheck[size][size],sum=0;
 printf("Enter Elements in matrix\n");
 for(i=0;i<size;i++)
 {
  for(j=0;j<size;j++)
  {
   scanf("%d",&a[i][j]);
  }
 }
 //Transpose of given matrix
 for(i=0;i<size;i++)
 {
  for(j=0;j<size;j++)
  {
   temp[i][j]=a[j][i];
  }
 }
 //Multiplying given A with A^T
 for(i=0;i<size;i++)
 {
  for(j=0;j<size;j++)
  {
   for(k=0;k<size;k++)
   {
    sum+=(a[i][k]*temp[k][j]);
   }
   identityCheck[i][j]=sum;
   sum=0;
  }
 }
 //Checking whether A*A^T resulted in Identity Matrix or not
 
 for(i=0;i<size;i++)
 {
  for(j=0;j<size;j++)
  {
   if(i==j && identityCheck[i][j]!=1)
   flag=0;
   if(i!=j && identityCheck[i][j]!=0)
   flag=0;
  }
 }
 //Checking for Orthogonal Matrix or not
 if(flag==1)
 {
  printf("Given Matrix is Orthogonal Matrix\n");
 }
 else
 {
  printf("Given Matrix is not an Orthogonal Matrix\n");
 }
}

Explanation:

//Coming Soon

Output: