% Chapter 13: Figure 13.42
%
%   The step response of the second-order sampled data
%    system 
%
%              0.3678z + 0.2644 
%     T(z) =  ------------------  .
%                z^2-z+0.6322
%
num=[1]; den=[1 1 0]; 
sysc=tf(num,den);
sysd=c2d(sysc,1,'zoh');
sys=feedback(sysd,[1]);
T=[0:1:20]; step(sys,T) 