ms14r21.m

《数字信号处理实验(MATLAB版)》这

xn=[1,0.5,0,0.5,1,1,0.5,0];
N=length(xn);
n=0:N-1;
subplot(2,2,1);stem(n,xn,'k');
title('x(n)');
k=0:N-1;
Xk=fft(xn,N);                %用FFT计算信号的DFT
subplot(2,1,2);stem(k,abs(Xk),'k'); 
title('Xk=DFT(x(n))');
xn1=ifft(Xk,N);            %用IFFT计算信号的IDFT
subplot(2,2,2);stem(n,xn1,'k'); 
title('x(n)=IDFT(Xk)');