gusucode.com > ​数字信号处理，包括：各种现有信号及随机信号的输入，从文件读取数据的输入 > Digital Signal Matlab ex1/IDFT.m

    axes(handles.axes4);
Xaxis=str2num(get(handles.EditX,'String'));
Yaxis=str2num(get(handles.EditY,'String'));
x=[-Xaxis:Xaxis];
global SignalTran;
Xk=SignalTran;
N=length(Xk);
n=0:N-1;
k=0:N-1;
WN=exp(-j*2*pi/N);
WNnk=WN.^(-n'*k);
y=Xk*WNnk/N;
%subplot(2,2,4);
%plot(x,y);
stem(x,y,'.k');
%length=max(y);
axis([-Xaxis,Xaxis,-Yaxis,Yaxis]);
title('离散傅立叶反变换')