X-Git-Url: https://git.creatis.insa-lyon.fr/pubgit/?p=CreaPhase.git;a=blobdiff_plain;f=octave_packages%2Fm%2Felfun%2Fasech.m;fp=octave_packages%2Fm%2Felfun%2Fasech.m;h=0bf1d489605338e0a6b40a10ffdb6d9db8e800e5;hp=0000000000000000000000000000000000000000;hb=1c0469ada9531828709108a4882a751d2816994a;hpb=63de9f36673d49121015e3695f2c336ea92bc278

diff --git a/octave_packages/m/elfun/asech.m b/octave_packages/m/elfun/asech.m
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+## Copyright (C) 1994-2012 John W. Eaton
+##
+## This file is part of Octave.
+##
+## Octave is free software; you can redistribute it and/or modify it
+## under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or (at
+## your option) any later version.
+##
+## Octave is distributed in the hope that it will be useful, but
+## WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+## General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with Octave; see the file COPYING.  If not, see
+## <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn {Mapping Function} {} asech (@var{x})
+## Compute the inverse hyperbolic secant of each element of @var{x}.
+## @seealso{sech}
+## @end deftypefn
+
+## Author: jwe
+
+function y = asech (x)
+
+  if (nargin != 1)
+    print_usage ();
+  endif
+
+  y = acosh (1 ./ x);
+
+endfunction
+
+%!test
+%! v = [0, pi*i];
+%! x = [1, -1];
+%! assert(all (abs (asech (x) - v) < sqrt (eps)));
+
+%!error asech ();
+
+%!error asech (1, 2);
+