C program to the determinant of a matrix; Through this tutorial, we will learn how to find determine of a matrix in the c program.
C Program to Find Determinant of a Matrix
#include<stdio.h>
#include<math.h>
#include<stdlib.h>
#define SIZE 10
int main()
{
float a[SIZE][SIZE], x[SIZE], ratio, det=1;
int i,j,k,n;
/* Inputs */
/* 1. Reading number of unknowns */
printf("Enter Order of Matrix: ");
scanf("%d", &n);
/* 2. Reading Matrix */
printf("\nEnter Coefficients of Matrix: \n");
for(i=0;i< n;i++)
{
for(j=0;j< n;j++)
{
printf("a[%d][%d]=",i,j);
scanf("%f", &a[i][j]);
}
}
/* Here we are using Gauss Elimination
Technique for transforming matrix to
upper triangular matrix */
/* Applying Gauss Elimination */
for(i=0;i< n;i++)
{
if(a[i][i] == 0.0)
{
printf("Mathematical Error!");
exit(0);
}
for(j=i+1;j< n;j++)
{
ratio = a[j][i]/a[i][i];
for(k=0;k< n;k++)
{
a[j][k] = a[j][k] - ratio*a[i][k];
}
}
}
/* Displaying upper triangular matrix */
/* Not required, just for the sake of understanding */
/* By analyzing upper triangular matrix you
will get what's going on :) */
printf("\nUpper Triangular Matrix: \n");
for(i=0;i< n;i++)
{
for(j=0;j< n;j++)
{
printf("%0.2f\t",a[i][j]);
}
printf("\n");
}
/* Finding determinant by multiplying
elements in principal diagonal elements */
for(i=0;i< n;i++)
{
det = det * a[i][i];
}
printf("\n\nDeterminant of given matrix is: %0.3f", det);
return 0;
}
The output of the above c program; as follows:
Enter Order of Matrix: 2 Enter Coefficients of Matrix: a[0][0]=1 a[0][1]=2 a[1][0]=3 a[1][1]=4 Upper Triangular Matrix: 1.00 2.00 0.00 -2.00 Determinant of given matrix is: -2.000
