function [a,b] = dft (y)
%	DFT - The Discrete Fourier Transform
%	[a, b] = DFT (y)
%	a, b are the cosine and sine components
%	     for j = 0, 1, ..., n/2
n = length (y);
n2 = floor (n / 2);
a = zeros (1,n2+1);
b = zeros (1,n2+1);
t = 2*pi*(0:n-1)/n;
f = 2.0 / n;
for j = 0:n2
	cs = cos (j * t);
	ss = sin (j * t);
	a(j+1) = f * (cs * y);
	b(j+1) = f * (ss * y);
end
a(1) = 0.5 * a(1);
a(n2+1) = 0.5 * a(n2+1);
b(1) = 0.0;
b(n2+1) = 0.0;