%% wave1dfreqdemo
%% show 1D pure wave forms as a function of frequency
 
%define sample rates and frequency

N = 32
tN = (0:(N-1))/N;  % discrete time points
K = N;  % number of displays
i = sqrt(-1);

% display results 
for k = 0:K
   sampwave = exp(2*pi*i*k*tN);
   
   subplot(3,1,1);
    plot([0,N],[0,0],'k', [k,k], [-0.5,0.5],'b', k,0.5,'ob',k,-0.5,'ob');
    axis([-1,N+1,-1.1,1.1]);
    title('frequency');
    drawnow

   subplot(3,1,2);
    plot(tN,real(sampwave),'r');
    axis([-0.1,1.1,-1.1,1.1]);
    title('real part');
    drawnow
   subplot(3,1,3);
    plot(tN,imag(sampwave),'g');
    axis([-0.1,1.1,-1.1,1.1]);
    title('imaginary part')
    disp(['k=',num2str(k),', press a key'])
    drawnow
   pause
   end