function [xn]=idft(Xk,N)
%Computes Inverse Discrete Fourier Transform
%------------------------------------------
%[Xk]=dft(xn,N)
%N=Length of DFT
%
n=[0:1:N-1];
k=[0:1:N-1];
WN=exp(-j*2*pi/N);%Wn factor
nk=n'*k;
WNnk=WN.^(-nk);  %DFT matrix  
xn=(Xk*WNnk)/N;