--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/scripts/plot/surface.m	Tue Nov 06 22:16:25 2007 +0000
@@ -0,0 +1,100 @@
+
+## Copyright (C) 1993, 1994, 1995, 1996, 1997, 1999, 2000, 2002, 2004,
+##               2005, 2006, 2007 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 {Function File} @var{h} = {} surface (@var{x}, @var{y}, @var{z}, @var{c})
+## @deftypefnx {Function File} @var{h} = {} surface (@var{x}, @var{y}, @var{z})
+## Plot a surface graphic object given matrices @var{x}, and @var{y} from @code{meshgrid} and
+## a matrix @var{z} corresponding to the @var{x} and @var{y} coordinates of
+## the surface.  If @var{x} and @var{y} are vectors, then a typical vertex
+## is (@var{x}(j), @var{y}(i), @var{z}(i,j)).  Thus, columns of @var{z}
+## correspond to different @var{x} values and rows of @var{z} correspond
+## to different @var{y} values.
+## @seealso{surf, mesh, patch, line}
+## @end deftypefn
+
+## Author: jwe
+
+function h = surface (x, y, z, c)
+
+  ax = gca();
+
+  if (nargin == 1)
+    c = z = x;
+    if (ismatrix (z))
+      [nr, nc] = size (z);
+      x = 1:nc;
+      y = (1:nr)';
+    else
+      error ("surface: argument must be a matrix");
+    endif
+  elseif (nargin == 3)
+    if (isvector (x) && isvector (y) && ismatrix (z))
+      if (rows (z) == length (y) && columns (z) == length (x))
+        x = x(:)';
+        y = y(:);
+      else
+        msg = "surface: rows (z) must be the same as length (y) and";
+        msg = sprintf ("%s\ncolumns (z) must be the same as length (x)", msg);
+        error (msg);
+      endif
+    elseif (ismatrix (x) && ismatrix (y) && ismatrix (z))
+      if (! (size_equal (x, y) && size_equal (x, z)))
+        error ("surface: x, y, and z must have same dimensions");
+      endif
+      c = z;
+    else
+      error ("surface: x and y must be vectors and z must be a matrix");
+    endif
+  elseif (nargin == 4)
+    if !(size_equal (z, c))
+      error ("surface: z and c must have same size");
+    endif
+    if (isvector (x) && isvector (y) && ismatrix (z))
+      if (rows (z) == length (y) && columns (z) == length (x))
+        x = x(:)';
+        y = y(:);
+      else
+        msg = "surface: rows (z) must be the same as length (y) and";
+        msg = sprintf ("%s\ncolumns (z) must be the same as length (x)", msg);
+        error (msg);
+      endif
+    elseif (ismatrix (x) && ismatrix (y) && ismatrix (z))
+      if (! (size_equal (x, y) && size_equal (x, z)))
+        error ("surface: x, y, and z must have same dimensions");
+      endif
+    else
+      error ("surface: x and y must be vectors and z must be a matrix");
+    endif
+  else
+    print_usage ();
+  endif
+
+  ## make a default surface object
+  tmp = __go_surface__ (ax, "xdata", x, "ydata", y, "zdata", z, "cdata", c);
+
+  set (ax, "view", [0, 90], "box", "off");
+  set (tmp, "FaceColor","flat");
+
+  if (nargout > 0)
+    h = tmp;
+  endif
+
+endfunction