#include 
int main() {
   array double num2[4] = {4, 8.4, 30.8, 60},
                den2[5] = {1, 4.12, 17.4, 30.8, 60};
   class CControl sys2;
   sys2.model("tf", num2, den2); // create a tf model
   printf("\nThe system is created with TF model\n");
   printf("System matrices obtained by printss() member function.\n");
   sys2.printss();
   printf("\n\n");
   int nx2, ny2, nu2;
   nx2 = sys2.size('x');  // obtain the number of states of the system
   ny2 = sys2.size('y');  // obtain the number of outputs of the system
   nu2 = sys2.size('u');  // obtain the number of inputs of the system
   array double A2[nx2][nx2], B2[nx2][nu2], C2[ny2][nx2], D2[ny2][nu2];
   sys2.ssdata(A2, B2, C2, D2);
   printf("System matrices obtained by ssdata() member function.\n");
   printf("A = \n%f\nB = \n%f\nC = \n%f\nD = \n%f\n", A2, B2, C2, D2);
   printf("ZPK information obtained by printzpk() member function.\n");
   sys2.printzpk();
   printf("\n\n");
   int nz2, np2;
   double k2;
   nz2 = sys2.size('z');
   np2 = sys2.size('p');
   array double complex z2[nz2], p2[np2];
   sys2.zpkdata(z2, p2, &k2);
   printf("ZPK information obtained by zpkdata() member function.\n");
   printf("z2 = %f\n p2 = %f\n k2 = %f\n", z2, p2, k2);
   return 0;
}