Linear Algebra and the C Language/a09c

Code study: GJ_TP_mR(Ab);

The algorithm consists of checking whether the matrix A is not singular (det_R(A) != 0). If it is not singular we call the function gj_TP_mR(Ab);
If the matrix has more columns than rows, we take a submatrix which has r rows and r columns where r is the number of rows of the matrix to calculate the determinant. Then if the submatrix is not singular we call the function gj_TP_mR(Ab);
If the matrix has more columns than rows the program stops.

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double **GJ_TP_mR(
double **Ab
)
{
double **A;

   if(Ab[R_SIZE][C0] == Ab[C_SIZE_A][C0])
     {
       A = i_RC_mR(Ab[R_SIZE][C0],Ab[C_SIZE_A][C0]);

       c_Ab_A_mR(Ab,A);

       if(det_R(A)) gj_TP_mR(Ab);
       
       f_mR(A);
      }

   else if(Ab[R_SIZE][C0] <  Ab[C_SIZE_A][C0])
     {
       A = i_RC_mR(Ab[R_SIZE][C0],Ab[R_SIZE][C0]);

       c_Ab_subArxr_mR(Ab,A);

       if(det_R(A)) gj_TP_mR(Ab);
       
       f_mR(A);
      }

    else if(Ab[R_SIZE][C0] >  Ab[C_SIZE_A][C0]) 
    
    {
     printf("\n Error : GJ_TP_mR();\n");
     printf("\n The number of colums\n");
     printf("\n must be superior or egal\n");
     printf("\n to the number of rows\n");
     printf("\n Press return to continue.\n");
     fflush(stdout);
     getchar();
     exit(EXIT_FAILURE);
    }
  
return(Ab);
}
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