ms10_2.m

《数字信号处理实验(MATLAB版)》这

b=[0.2,0.1,0.3,0.1,0.2];
a=[1,-1.1,1.5,-0.7,0.3];
n=(0:1000)*pi/1000;
[h,w]=freqz(b,a,n);
subplot(2,1,1),plot(n/pi,abs(h));grid
axis([0,1,1.1*min(abs(h)),1.1*max(abs(h))]);
ylabel('幅度');
subplot(2,1,2),plot(n/pi,angle(h));grid
axis([0,1,1.1*min(angle(h)),1.1*max(angle(h))]);
ylabel('相位');
xlabel('以pi为单位的频率');