Linear Algebra and the C Language/a05m

Determinant: Code study

The function i_RC_mR(A[R_SIZE][C0], A[C_SIZE][C0]); reads the size of the matrix directly from memory.

The function pivotbest_mR(); returns 1, if there is an even change of rows and columns, and returns -1, if there is an odd change of rows and columns.

The function zero_under_pivot_mR(); returns the value of the pivot.

/* ------------------------------------ */
/* ------------------------------------ */
double det_R(
double **A
)
{
double **T = c_mR(A,    i_RC_mR(A[R_SIZE][C0], A[C_SIZE][C0]));
double deter=1;
int rc;

    for( rc=C1; rc<T[C_SIZE][C0]; rc++)
       {
        deter *= pivotbest_mR(T,rc);
        deter *= zero_under_pivot_mR(T,rc); 
       }

   f_mR(T);

return(deter);
}
/* ------------------------------------ */
/* ------------------------------------ */