update packages

[CreaPhase.git] / octave_packages / m / elfun / sec.m

diff --git a/octave_packages/m/elfun/sec.m b/octave_packages/m/elfun/sec.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} {} sec (@var{x})
+## Compute the secant for each element of @var{x} in radians.
+## @seealso{asec, secd, sech}
+## @end deftypefn
+
+## Author: jwe
+
+function y = sec (x)
+
+  if (nargin != 1)
+    print_usage ();
+  endif
+
+  y = 1 ./ cos(x);
+
+endfunction
+
+%!test
+%! rt2 = sqrt (2);
+%! rt3 = sqrt (3);
+%! x = [0, pi/6, pi/4, pi/3, 2*pi/3, 3*pi/4, 5*pi/6, pi];
+%! v = [1, 2*rt3/3, rt2, 2, -2, -rt2, -2*rt3/3, -1];
+%! assert(all (abs (sec (x) - v) < sqrt (eps)));
+
+%!error sec ();
+
+%!error sec (1, 2);
+