c1210.m

matlab例程MATLAB 6.x版的内建数据类型（Built-in data type）就有5种以上

clear;
N=49;
m=(N-1)/2;
k=0:N-1;

T=1;
h1=cos((k-m)*pi)./((k-m)*T);h1(25)=0;

num1=h1;
den1=[1, zeros(1,N-1)];
w=-pi:pi/100:pi;
H1=freqz(num1,den1,w);
mag1=abs(H1);
phase1=180/pi*unwrap(angle(H1));

h2=cos((k-m)*pi)./((k-m)*T).*(0.54+0.46*cos(pi*(k-m)./m));h2(25)=0;

num2=h2;
den2=den1;
H2=freqz(num2,den2,w);
mag2=abs(H2);
phase2=180/pi*unwrap(angle(H2));
subplot(2,1,1);
plot(w,mag1,w,mag2);
subplot(2,1,2);
plot(w,phase2,w,phase1);