% subspace method
[thetas,residues]=sm(R,A,B,2);
arrowb(thetas,residues); hold on;
Ac=compan(eye(1,6));
Bc=eye(5,1);
That=dlsim_complex(Ac,Bc,y'); 
[th_esprit,r_esprit]=sm(That,Ac,Bc,2); % ESPRIT spectral lines
arrowg(th_esprit,r_esprit);