update packages

[CreaPhase.git] / octave_packages / m / plot / triplot.m

diff --git a/octave_packages/m/plot/triplot.m b/octave_packages/m/plot/triplot.m
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+## Copyright (C) 2007-2012 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} {} triplot (@var{tri}, @var{x}, @var{y})
+## @deftypefnx {Function File} {} triplot (@var{tri}, @var{x}, @var{y}, @var{linespec})
+## @deftypefnx {Function File} {@var{h} =} triplot (@dots{})
+## Plot a triangular mesh in 2D@.  The variable @var{tri} is the triangular
+## meshing of the points @code{(@var{x}, @var{y})} which is returned from
+## @code{delaunay}.  If given, @var{linespec} determines the properties
+## to use for the lines. 
+##
+## The optional return value @var{h} is a graphics handle to the created plot.
+## @seealso{plot, trimesh, trisurf, delaunay}
+## @end deftypefn
+
+function h = triplot (tri, x, y, varargin)
+
+  if (nargin < 3)
+    print_usage ();
+  endif
+
+  idx = tri(:, [1, 2, 3, 1]).';
+  nt = rows (tri);
+  handle = plot ([x(idx); NaN(1, nt)](:),
+                 [y(idx); NaN(1, nt)](:), varargin{:});
+
+  if (nargout > 0)
+    h = handle;
+  endif
+
+endfunction
+
+
+%!demo
+%! clf
+%! old_state = rand ("state");
+%! restore_state = onCleanup (@() rand ("state", old_state));
+%! rand ("state", 2);
+%! N = 20;
+%! x = rand (N, 1);
+%! y = rand (N, 1);
+%! tri = delaunay (x, y);
+%! triplot (tri, x, y);
+