C++ Programming Code Examples
C++ > Mathematics Code Examples
C++ Program to Compute Determinant of a Matrix
/* C++ Program to Compute Determinant of a Matrix
This is a C++ Program to compute the determinant of the given matrix. */
#include<conio.h>
#include<iostream>
#include<math.h>
using namespace std;
double d = 0;
double det(int n, double mat[10][10]);
double det(int n, double mat[10][10])
{
double submat[10][10];
if (n == 2)
return ((mat[0][0] * mat[1][1]) - (mat[1][0] * mat[0][1]));
else
{
for (int c = 0; c < n; c++)
{
int subi = 0; //submatrix's i value
for (int i = 1; i < n; i++)
{
int subj = 0;
for (int j = 0; j < n; j++)
{
if (j == c)
continue;
submat[subi][subj] = mat[i][j];
subj++;
}
subi++;
}
d = d + (pow(-1, c) * mat[0][c] * det(n - 1, submat));
}
}
return d;
}
int main(int argc, char **argv)
{
cout << "Enter the dimension of the matrix:\n";
int n;
cin >> n;
double mat[10][10];
cout << "Enter the elements of the matrix:\n";
for (int i = 0; i < n; i++)
{
for (int j = 0; j < n; j++)
{
cin >> mat[j][i];
}
}
cout << "The determinant of the given matrix is: " << det(n, mat);
return 0;
}
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