
function test_gdft
% Some simple gdft tests

% ------- test_gdft.m --------------------------------------
% Marios Athineos, marios@ee.columbia.edu
% http://www.ee.columbia.edu/~marios/
% Copyright (c) 2004-2005 by Columbia University.
% All rights reserved.
% ----------------------------------------------------------

% The (0,0) GDFT is simply the DFT (normalized)
% In order to get the matrix just transform the identity
G1 = gdft(eye(4),0,0)

% And here is the corresponding DFT
D  = fft(eye(4))/sqrt(4)

% Another way to generate the matrix is through the dedicated
% function.  The code for gdftmtx() shows a simpler way to
% without twiddling factors (but slow)
G2 = gdftmtx(4,0,0)

% Now the odd-frequency OFDFT is simply
G3 = gdft(eye(4),1/2,0)

% And as a sanity for forward/inverse we get the identity
I  = igdft(gdft(eye(4),1/2,0),1/2,0)
