[Changeset]: Add the plotmatrix function

[David Bateman]

Not sure how much use this function really is, but as it and comet are 
the only 2D core matlab plotting functions that aren't implemented, for 
completeness I include an implementation of this function here.

Regards
David

# HG changeset patch
# User David Bateman <address@hidden>
# Date 1222029822 -7200
# Node ID 4855ea64d1d5afefc1e3feb7510e428c377c52af
# Parent  d66c8dfebd4db36204b59f3721ee575f6a5e845d
Add the plotmatrix function

diff --git a/scripts/ChangeLog b/scripts/ChangeLog
--- a/scripts/ChangeLog
+++ b/scripts/ChangeLog
@@ -1,3 +1,8 @@ 2008-09-20  David Bateman  <address@hidden
+2008-09-21  David Bateman  <address@hidden>
+
+       * plot/plotmatrix.m: New function.
+       * plot/Makefile.in (SOURCES): Add it here.
+
 2008-09-20  David Bateman  <address@hidden>
 
        general/quadgk.m: No function count in quadgk and so don't try and
diff --git a/scripts/plot/Makefile.in b/scripts/plot/Makefile.in
--- a/scripts/plot/Makefile.in
+++ b/scripts/plot/Makefile.in
@@ -142,6 +142,7 @@ SOURCES = \
   peaks.m \
   pie.m \
   plot.m \
+  plotmatrix.m \
   plotyy.m \
   plot3.m \
   plotyy.m \
diff --git a/scripts/plot/plotmatrix.m b/scripts/plot/plotmatrix.m
new file mode 100644
--- /dev/null
+++ b/scripts/plot/plotmatrix.m
@@ -0,0 +1,189 @@
+## Copyright (C) 2008 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} {} plotmatrix (@var{x}, @var{y})
+## @deftypefnx {Function File} {} plotmatrix (@var{x})
+## @deftypefnx {Function File} {} plotmatrix (@dots{}, @var{style})
+## @deftypefnx {Function File} {} plotmatrix (@var{h}, @dots{})
+## @deftypefnx {Function File} address@hidden, @var{ax}, @var{bigax}, @var{p}, 
@var{pax}] =} plotmatrix (@dots{})
+## Scatter plot of the columns of one matrix against another. Given the
+## arguments @var{x} and @var{y}, that have a matching number of rows,
+## @code{plotmatrix} plots a set of axes corresponding to
+##
+## @example
+## plot (@var{x} (:, i), @var{y} (:, j)
+## @end example
+##
+## Given a single argument @var{x}, then this is equivalent to 
+##
+## @example
+## plotmatrix (@var{x}, @var{x})
+## @end example
+##
+## @noindent
+## except that the diagonal of the set of axes will be replaced with the
+## histogram @code{hist (@var{x} (:, i))}.
+##
+## The marker to use can be changed with the @var{style} argument, that is a 
+## string defining a marker in the same manner as the @code{plot}
+## command. If a leading axes handle @var{h} is passed to
+## @code{plotmatrix}, then this axis will be used for the plot.
+##
+## The optional return value @var{h} provides handles to the individual
+## graphics objects in the scatter plots, whereas @var{ax} returns the
+## handles to the scatter plot axis objects. @var{bigax} is a hidden
+## axis object that surrounds the other axes, such that the commands 
+## @code{xlabel}, @code{title}, etc, will be associated with this hidden
+## axis. Finally @var{p} returns the graphics objects associated with
+## the histogram and @var{pax} the corresponding axes objects.
+##
+## @example
+## @group
+## plotmatrix (randn (100, 3), 'g+')
+## @end group
+## @end example
+##
+## @end deftypefn
+
+function [h, ax, bigax, p, pax] = plotmatrix (varargin)
+
+  [bigax2, varargin, nargin] = __plt_get_axis_arg__ ("plotmatrix", 
varargin{:});
+
+  if (nargin > 3 || nargin < 1)
+    print_usage ();
+  else
+    oldh = gca ();
+    unwind_protect
+      axes (bigax2);
+      newplot ();
+      [h2, ax2, p2, pax2, need_usage] = __plotmatrix__ (bigax2, varargin{:});
+      if (need_usage)
+       print_usage ();
+      endif
+      if (nargout > 0)
+       h = h2;
+       ax = ax2;
+       bigax = bigax2;
+       p = p2;
+       pax = pax2;
+      endif
+      axes (bigax2);
+      ctext = text (0, 0, "", "visible", "off", 
+                   "handlevisibility", "off", "xliminclude", "off",  
+                   "yliminclude", "off", "zliminclude", "off",
+                   "deletefcn", address@hidden, [ax2; pax2]});
+      set (bigax2, "visible", "off");
+    unwind_protect_cleanup
+      axes (oldh);
+    end_unwind_protect
+  endif
+endfunction
+
+%!demo
+%! plotmatrix (randn (100, 3), 'g+')
+
+function plotmatrixdelete (h, d, ax)
+  for i = 1 : numel (ax)
+    hc = ax(i);
+    if (ishandle (hc) && strcmp (get (hc, "type"), "axes") && 
+       strcmp (get (hc, "beingdeleted"), "off"))
+      parent = get (hc, "parent");
+      ## If the parent is invalid or being deleted, then do nothing
+      if (ishandle (parent) && strcmp (get (parent, "beingdeleted"), "off"))
+       delete (hc);
+      endif
+    endif
+  endfor
+endfunction
+
+function [h, ax, p, pax, need_usage] = __plotmatrix__ (bigax, varargin)
+  need_usage = false;
+  have_line_spec = false;
+  have_hist = false;
+  parent = get (bigax, "parent");
+  for i = 1 : nargin - 1
+    arg = varargin{i};
+    if (ischar (arg) || iscell (arg))
+      [linespec, valid] = __pltopt__ ("plotmatrix", varargin{i}, false);
+      if (valid)
+       have_line_spec = true;      
+       linespec = varargin(i);
+       varargin(i) = [];
+       nargin = nargin - 1;
+       break;
+      else
+       need_usage = true;
+       returm;
+      endif
+    endif
+  endfor
+
+  if (nargin == 2)
+    X = varargin{1};
+    Y = X;
+    have_hist = true;
+  elseif (nargin == 3)
+    X = varargin{1};
+    Y = varargin{2};
+  else
+    need_usage = true;
+    returm;
+  endif
+
+  if (rows(X) != rows(Y))
+    error ("plotmatrix: dimension mismatch in the arguments");
+  endif
+
+  [dummy, m] = size (X);
+  [dummy, n] = size (Y);
+
+  h = [];
+  ax = [];
+  p = [];
+  pax = [];
+
+  xsize = 0.9 / m;
+  ysize = 0.9 / n;
+  xoff = 0.05;
+  yoff = 0.05;
+  border = [0.130, 0.110, 0.225, 0.185] .* [xsize, ysize, xsize, ysize];
+  border(3:4) = - border(3:4) - border(1:2);
+
+  for i = 1 : n
+    for j = 1 : m
+      pos = [xsize * (j - 1) + xoff, ysize * (n - i) + yoff, xsize, ysize];
+      tmp = axes ("outerposition", pos, "position", pos + border,
+                 "parent", parent);
+      if (i == j && have_hist)
+       pax = [pax ; tmp];
+       [nn, xx] = hist (X(:, i));
+       tmp = bar (xx, nn, 1.0);
+       p = [p; tmp];
+      else
+       ax = [ax ; tmp];
+       if (have_line_spec)
+         tmp = plot (X (:, i), Y (:, j), linespec);
+       else
+         tmp = plot (X (:, i), Y (:, j), ".");
+       endif
+       h = [h ; tmp];
+      endif
+    endfor
+  endfor
+endfunction