how "hinfmix" function works?

Hi, I ran a very simple codes to see how "hinfmix" works. but I found 3 errors regarding to "hinfmix" function. I cannot understand what is the problem. it is because of my program or there is something wrong in "hinfmix"? here is my code and errors:

s=zpk('s');

G=10*(s-1)/(s+1)^2;

W1=0.1*(s+100)/(100*s+1); W2=0.1; W3=[];

P=augw(G,W1,W2,W3);

r=[1 1 1];

obj=[1,1,0.1,0.1];

[K,CL,GAM]=hinfmix(P,r,obj );

L=G*K; S=inv(1+L); T=1-S;

sigma(L,'k-.',S,'r',T,'g')

??? Error using ==> lti.subsref at 56 Use two or more subscripts to index into MIMO models or LTI arrays, as in the "sys(2,1)" command.

Error in ==> islsys at 11 sys=sys(:);

Error in ==> hinfmix at 59 elseif ~islsys(G),

Error in ==> Untitled at 21 [K,CL,GAM]=hinfmix(P,r,obj );