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+## Copyright (C) 2022 The Octave Project Developers
+##
+## This program 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.
+##
+## This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn {}  {@var{lat2} =} meridianfwd (@var{lat}, @var{s})
+## @deftypefnx {} {@var{lat2} =} meridianfwd (@var{lat}, @var{s}, @var{spheroid})
+## @deftypefnx {} {@var{lat2} =} meridianfwd (@var{lat}, @var{s}, @var{spheroid}, @var{angleUnit})
+## Retuns the new latitude given a starting latitude and distance travelled
+## along a meridian.
+##
+## Inputs
+##
+## @itemize
+## @item
+## @var{lat1}: the starting latitude.
+##
+## @item
+## @var{s} the distance travelled.  The units are based on the ellipsoid.
+## The default is in meters but should match that of the ellipsoid (if any).
+##
+## @item
+## (optional) @var{spheroid}: referenceEllipsoid (parameter struct, name or
+## code): the default is 'wgs84'.
+##
+## @item
+## (optional) @var{angleUnit}: string for angular units ('degrees' or 'radians',
+## case-insensitive, just the first character will do). Default is 'radians'.
+##
+## Output
+## @item
+## @var{lat2}: the final latitude after travelling a distance of @var{s}
+## @end itemize
+##
+## Example
+## @example
+## lat = meridianfwd (40, 1e6)
+## lat =  48.983
+## @end example
+##
+## @seealso{meridianarc, geodeticfwd}
+## @end deftypefn
+
+function [lat2] = meridianfwd (lat, s, spheroid = "wgs84", angleUnit = "radians")
+
+  if (nargin < 2 || nargin > 4)
+    print_usage();
+  endif
+
+  lat2 = geodeticfwd (lat, 0, s, 0, spheroid, angleUnit, "length");
+
+endfunction
+
+
+%!test
+%! a = rad2deg (meridianfwd (-pi/4, [60 120] * 45 * 1846.2756967249574, 'wgs84'));
+%! assert (a, [0, 45], 5e-7);
+