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## -*- texinfo -*-
## @deftypefn {} {} coth (@var{x})
## Compute the hyperbolic cotangent of each element of @var{x}.
## @seealso{acoth}
## @end deftypefn

function y = coth (x)

  if (nargin != 1)
    print_usage ();
  endif

  y = 1 ./ tanh (x);

endfunction


%!test
%! x = [pi/2*i, 3*pi/2*i];
%! v = [0, 0];
%! assert (coth (x), v, sqrt (eps));

%!error coth ()
%!error coth (1, 2)