function y = circ(x, n)% circ -- Circularly shift the elements of a vector.%%  Usage%    y = circ(x, n)%%  Inputs%    x      signal vector.%    n      shift factor. + is right or down, - is left or up.%%  Outputs%    y      shifted vector% Copyright (C) -- see DiscreteTFDs/Copyrighterror(nargchk(1, 2, nargin));x = x(:);N = length(x);n = rem(n,N);if n<0,  n = n+N;endy = [x(N-n+1:N); x(1:N-n)];