ms11_2.m

《数字信号处理实验(MATLAB版)》这

xn=[ones(1,4),zeros(1,12)];
N=length(xn);
n=0:N-1;
Xk=dfs(xn,N);
xn1=idfs(Xk,N);
subplot(2,2,1),stem(n,xn,'k');
axis([0,N-1,0,1.1*max(xn)]);
title('x(n)');
subplot(2,2,2),stem(n,abs(xn1),'k');
axis([0,N-1,0,1.1*max(abs(xn1))]);
title('IDFS|X(k)|');
subplot(2,2,3),stem(n,abs(Xk),'k');
title('|X(k)|');
subplot(2,2,4),stem(n,angle(Xk),'k');
title('arg|X(k)|');