l=0.2;  %axe inter-roue
alpha=1/l;
omega=0.2;
ksi=0;
ki_teta=omega*omega/alpha;
kp_teta=2*ksi*omega/alpha;
tau=0.001;


% p(s) = s^2 + (kp*s + ki)e^{-tau s}/l
% p1 = s^2
% p2 = 

[num, denum] = pade(tau, 1) 

p1 = [1 0 0];
p2 = [kp_teta/l ki_teta/l];

ph = conv(denum,p1) 
pl = conv(num,p2)

[sh1, sh2] = size(ph); %sh2 = degre de ph
[sl1, sl2] = size(pl); %sl2 = degre de pl
nbzeroadd = sh2 - sl2;

pll = [zeros(nbzeroadd) pl]; 
%ajouter des coef 0 pour que les vecteurs ont la meme taille
%afin de faire l'addition de deux polynomes


p = ph + pll
[s1, s2] = size(p);
hurwitz(p,s2-1)