function d = disteu(x, y)
% DISTEU Pairwise Euclidean distances between columns of two matrices
% Input:
% x, y: Two matrices whose each column is an a vector data.
% Output:
% d: Element d(i,j) will be the Euclidean distance between two
% column vectors X(:,i) and Y(:,j)
% Note:
% The Euclidean distance D between two vectors X and Y is:
% D = sum((x-y).^2).^0.5
[M, N] = size(x);
[M2, P] = size(y);
if(M ~= M2),
error('Matrix dimensions do not match.')
end
d = zeros(N, P);
if(N < P),
copies = zeros(1,P);
for n = 1:N,
d(n,:) = sum((x(:, n+copies) - y) .^2, 1);
end
else
copies = zeros(1,N);
for p = 1:P,
d(:,p) = sum((x - y(:, p+copies)) .^2, 1)';
end
end
d = d.^0.5;
