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## -*- texinfo -*-
## @deftypefn {} {@var{y} =} acsch (@var{x})
## Compute the inverse hyperbolic cosecant of each element of @var{x}.
## @seealso{csch}
## @end deftypefn

function y = acsch (x)

  if (nargin < 1)
    print_usage ();
  endif

  y = asinh (1 ./ x);

endfunction


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

%!error <Invalid call> acsch ()