%  ex_02_08_1.m :  習題 2.8

clear all;
close all;

b=1;
a=[1 -1.13 0.64];
figure(1);
zplane(b,a);
[H,w]=freqz(b,a,256,'whole',1);
Hr=abs(H);
Hphase=angle(H);
Hphase=unwrap(Hphase);
figure(2);
subplot(211);plot(w,Hr);grid;
subplot(212);plot(w,Hphase);grid;