Discete Cosine Series Tutorial: Snippet 1

DCS1.m

n  = 15;      % number of collocation points is (n+1)
nmodes = 5;   % number of modes of the DCS

xi = [0:n]'/(n+1); % collocation points for DCS
V  = zeros(n+1, nmodes); 

%
% V: stack the nmodes DCS basis functions columnwise
%

for j = 1:nmodes
  V(:,j) = cos(2*pi*(j-1)*xi);
endfor

(2/n+1)*V' * V