/***********************************************************
* You can use all the programs on  www.c-program-example.com
* for personal and learning purposes. For permissions to use the
* programs for commercial purposes,
* contact [email protected]
* To find more C programs, do visit www.c-program-example.com
* and browse!
* 
*                      Happy Coding
***********************************************************/

#include<stdio.h> 
#include<math.h> 
float detrminant(float[][], float);
void cofactors(float[][], float);
void trans(float[][], float[][], float);
main() {
 float a[25][25], n, d;
 int i, j;
 printf("Enter the order of the matrix:n");
 scanf("%f", &n);
 printf("Enter the elemnts into the matrix:n");
 for (i = 0; i < n; i++) {
  for (j = 0; j < n; j++) {
   scanf("%f", &a[i][j]);
  }
 }
 d = detrminant(a, n);
 printf("nTHE DETERMINANT IS=%2f", d);
 if (d == 0)
  printf("nMATRIX IS NOT INVERSIBLEn");
 else
  cofactors(a, n);
}

float detrminant(float a[25][25], float k) {
 float s = 1, det = 0, b[25][25];
 int i, j, m, n, c;
 if (k == 1) {
  return (a[0][0]);
 } else {
  det = 0;
  for (c = 0; c < k; c++) {
   m = 0;
   n = 0;
   for (i = 0; i < k; i++) {
    for (j = 0; j < k; j++) {
     b[i][j] = 0;
     if (i != 0 && j != c) {
      b[m][n] = a[i][j];
      if (n < (k - 2))
       n++;
      else {
       n = 0;
       m++;
      }
     }
    }
   }
   det = det + s * (a[0][c] * detrminant(b, k - 1));
   s = -1 * s;
  }
 }
 return (det);
}

void cofactors(float num[25][25], float f) {
 float b[25][25], fac[25][25];
 int p, q, m, n, i, j;
 for (q = 0; q < f; q++) {
  for (p = 0; p < f; p++) {
   m = 0;
   n = 0;
   for (i = 0; i < f; i++) {
    for (j = 0; j < f; j++) {
     b[i][j] = 0;
     if (i != q && j != p) {
      b[m][n] = num[i][j];
      if (n < (f - 2))
       n++;
      else {
       n = 0;
       m++;
      }
     }
    }
   }
   fac[q][p] = pow(-1, q + p) * detrminant(b, f - 1);
  }
 }
 trans(num, fac, f);
}

void trans(float num[25][25], float fac[25][25], float r)

{
 int i, j;
 float b[25][25], inv[25][25], d;
 for (i = 0; i < r; i++) {
  for (j = 0; j < r; j++) {
   b[i][j] = fac[j][i];
  }
 }

 d = detrminant(num, r);
 inv[i][j] = 0;
 for (i = 0; i < r; i++) {
  for (j = 0; j < r; j++) {
   inv[i][j] = b[i][j] / d;
  }
 }

 printf("nTHE INVERSE OF THE MATRIX:n");
 for (i = 0; i < r; i++) {
  for (j = 0; j < r; j++) {
   printf("t%2f", inv[i][j]);
  }
  printf("n");
 }
}

Read more Similar C Programs
Matrix Programs
Learn C Programming

You can easily select the code by double clicking on the code area above.

To get regular updates on new C programs, you can Follow @c_program

You can discuss these programs on our Facebook Page. Start a discussion right now,

our page!

Share this program with your Facebook friends now! by liking it

(you can send this program to your friend using this button)

Like to get updates right inside your feed reader? Grab our feed!