function V = ar2vec(A)
%AR2VEC V=ar2vec(A)
%concenates the columns of 2D array A into a single column vector V

sz = size(A);
n=sz(1,2);
i=1;
V=[];

while i<(n+1)
    V=[V;A(:,i)];
    i=i+1;
end

end