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## -*- texinfo -*-
## @deftypefn {} {@var{y} =} sech (@var{x})
## Compute the hyperbolic secant of each element of @var{x}.
## @seealso{asech}
## @end deftypefn

function y = sech (x)

if (nargin < 1)
    print_usage ();
  endif

  y = 1 ./ cosh (x);

endfunction


%!test
%! x = [0, pi*i];
%! v = [1, -1];
%! assert (sech (x), v, sqrt (eps));

%!error <Invalid call> sech ()