[Ak,Bk,Ck,Dk]=kit;
load_system('ps10b_3');
assignin('base','Ak',Ak)
assignin('base','Bk',Bk)
assignin('base','Ck',Ck)
assignin('base','Dk',Dk)

[A,B,C,D]=linmodv5('ps10b_3');
P=ss(A,B,C,D);
norm(P,inf);