view scripts/elfun/secd.m @ 15489:481417a57a2d

improve sign and signbit docs * mappers.cc (Fsign): Note sign (-0) is 0. Add @seealso for signbit. (Fsignbit): Add @seealso for sign.
author John W. Eaton <jwe@octave.org>
date Thu, 04 Oct 2012 10:20:59 -0400
parents f3d52523cde1
children
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## Copyright (C) 2006-2012 David Bateman
##
## 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 {Function File} {} secd (@var{x})
## Compute the secant for each element of @var{x} in degrees.
## @seealso{asecd, sec}
## @end deftypefn

## Author: David Bateman <dbateman@free.fr>

function y = secd (x)

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

  y = 1 ./ cosd (x);

endfunction


%!assert (secd (0:10:80), sec (pi*[0:10:80]/180), -10*eps)
%!assert (secd ([0, 180, 360]) != Inf)
%!assert (secd ([90, 270]) == Inf)

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