example2_14.m

西交大刘树棠写的《数字信号处理》那本书的所有源代码

b=1;
a=[1,-0.9];
figure(1);
zplane(b,a);
figure(2);
[H,w]=freqz(b,a,100);
magH=abs(H);phaH=angle(H);
subplot(2,1,1);plot(w/pi,magH);grid;
xlabel('freq');ylabel('amp');
subplot(2,1,2);plot(w/pi,phaH/pi);grid;
xlabel('freq');ylabel('phase');