diff scripts/plot/draw/contourc.m @ 17572:7bb76a22cde1

maint: Split scripts/plot directory into 4 pieces. scripts/gui : user-interface functions scripts/plot/appearance : functions controlling plot appearance scripts/plot/draw : plotting functions which produce graphs scripts/plot/util : low-level plotting functions and utilities. * scripts/gui/guidata.m, scripts/gui/guihandles.m, scripts/gui/module.mk, scripts/gui/private/__file_filter__.m, scripts/gui/private/__fltk_file_filter__.m, scripts/gui/private/__is_function__.m, scripts/gui/private/__uigetdir_fltk__.m, scripts/gui/private/__uigetfile_fltk__.m, scripts/gui/private/__uiobject_split_args__.m, scripts/gui/private/__uiputfile_fltk__.m, scripts/gui/uicontextmenu.m, scripts/gui/uicontrol.m, scripts/gui/uigetdir.m, scripts/gui/uigetfile.m, scripts/gui/uimenu.m, scripts/gui/uipanel.m, scripts/gui/uipushtool.m, scripts/gui/uiputfile.m, scripts/gui/uiresume.m, scripts/gui/uitoggletool.m, scripts/gui/uitoolbar.m, scripts/gui/uiwait.m, scripts/gui/waitbar.m, scripts/gui/waitforbuttonpress.m: Moved from scripts/plot to scripts/gui * scripts/plot/appearance/__clabel__.m, scripts/plot/appearance/__getlegenddata__.m, scripts/plot/appearance/axis.m, scripts/plot/appearance/box.m, scripts/plot/appearance/caxis.m, scripts/plot/appearance/clabel.m, scripts/plot/appearance/daspect.m, scripts/plot/appearance/diffuse.m, scripts/plot/appearance/grid.m, scripts/plot/appearance/gtext.m, scripts/plot/appearance/hidden.m, scripts/plot/appearance/legend.m, scripts/plot/appearance/orient.m, scripts/plot/appearance/pbaspect.m, scripts/plot/appearance/private/__axis_label__.m, scripts/plot/appearance/private/__axis_limits__.m, scripts/plot/appearance/shading.m, scripts/plot/appearance/specular.m, scripts/plot/appearance/text.m, scripts/plot/appearance/title.m, scripts/plot/appearance/view.m, scripts/plot/appearance/whitebg.m, scripts/plot/appearance/xlabel.m, scripts/plot/appearance/xlim.m, scripts/plot/appearance/ylabel.m, scripts/plot/appearance/ylim.m, scripts/plot/appearance/zlabel.m, scripts/plot/appearance/zlim.m: Moved from scripts/plot to subdir appearance. * scripts/plot/draw/area.m, scripts/plot/draw/bar.m, scripts/plot/draw/barh.m, scripts/plot/draw/colorbar.m, scripts/plot/draw/comet.m, scripts/plot/draw/comet3.m, scripts/plot/draw/compass.m, scripts/plot/draw/contour.m, scripts/plot/draw/contour3.m, scripts/plot/draw/contourc.m, scripts/plot/draw/contourf.m, scripts/plot/draw/cylinder.m, scripts/plot/draw/ellipsoid.m, scripts/plot/draw/errorbar.m, scripts/plot/draw/ezcontour.m, scripts/plot/draw/ezcontourf.m, scripts/plot/draw/ezmesh.m, scripts/plot/draw/ezmeshc.m, scripts/plot/draw/ezplot.m, scripts/plot/draw/ezplot3.m, scripts/plot/draw/ezpolar.m, scripts/plot/draw/ezsurf.m, scripts/plot/draw/ezsurfc.m, scripts/plot/draw/feather.m, scripts/plot/draw/fill.m, scripts/plot/draw/fplot.m, scripts/plot/draw/hist.m, scripts/plot/draw/isocolors.m, scripts/plot/draw/isonormals.m, scripts/plot/draw/isosurface.m, scripts/plot/draw/line.m, scripts/plot/draw/loglog.m, scripts/plot/draw/loglogerr.m, scripts/plot/draw/mesh.m, scripts/plot/draw/meshc.m, scripts/plot/draw/meshz.m, scripts/plot/draw/pareto.m, scripts/plot/draw/patch.m, scripts/plot/draw/pcolor.m, scripts/plot/draw/peaks.m, scripts/plot/draw/pie.m, scripts/plot/draw/pie3.m, scripts/plot/draw/plot.m, scripts/plot/draw/plot3.m, scripts/plot/draw/plotmatrix.m, scripts/plot/draw/plotyy.m, scripts/plot/draw/polar.m, scripts/plot/draw/private/__add_datasource__.m, scripts/plot/draw/private/__bar__.m, scripts/plot/draw/private/__contour__.m, scripts/plot/draw/private/__errcomm__.m, scripts/plot/draw/private/__errplot__.m, scripts/plot/draw/private/__ezplot__.m, scripts/plot/draw/private/__interp_cube__.m, scripts/plot/draw/private/__line__.m, scripts/plot/draw/private/__marching_cube__.m, scripts/plot/draw/private/__patch__.m, scripts/plot/draw/private/__pie__.m, scripts/plot/draw/private/__plt__.m, scripts/plot/draw/private/__quiver__.m, scripts/plot/draw/private/__scatter__.m, scripts/plot/draw/private/__stem__.m, scripts/plot/draw/quiver.m, scripts/plot/draw/quiver3.m, scripts/plot/draw/rectangle.m, scripts/plot/draw/ribbon.m, scripts/plot/draw/rose.m, scripts/plot/draw/scatter.m, scripts/plot/draw/scatter3.m, scripts/plot/draw/semilogx.m, scripts/plot/draw/semilogxerr.m, scripts/plot/draw/semilogy.m, scripts/plot/draw/semilogyerr.m, scripts/plot/draw/shrinkfaces.m, scripts/plot/draw/slice.m, scripts/plot/draw/sombrero.m, scripts/plot/draw/sphere.m, scripts/plot/draw/stairs.m, scripts/plot/draw/stem.m, scripts/plot/draw/stem3.m, scripts/plot/draw/stemleaf.m, scripts/plot/draw/surf.m, scripts/plot/draw/surface.m, scripts/plot/draw/surfc.m, scripts/plot/draw/surfl.m, scripts/plot/draw/surfnorm.m, scripts/plot/draw/tetramesh.m, scripts/plot/draw/trimesh.m, scripts/plot/draw/triplot.m, scripts/plot/draw/trisurf.m, scripts/plot/draw/waterfall.m: Moved from plot/ to subdir draw. * scripts/plot/util/__actual_axis_position__.m, scripts/plot/util/__default_plot_options__.m, scripts/plot/util/__gnuplot_drawnow__.m, scripts/plot/util/__next_line_color__.m, scripts/plot/util/__next_line_style__.m, scripts/plot/util/__plt_get_axis_arg__.m, scripts/plot/util/__pltopt__.m, scripts/plot/util/allchild.m, scripts/plot/util/ancestor.m, scripts/plot/util/axes.m, scripts/plot/util/cla.m, scripts/plot/util/clf.m, scripts/plot/util/close.m, scripts/plot/util/closereq.m, scripts/plot/util/colstyle.m, scripts/plot/util/copyobj.m, scripts/plot/util/figure.m, scripts/plot/util/findall.m, scripts/plot/util/findfigs.m, scripts/plot/util/findobj.m, scripts/plot/util/gca.m, scripts/plot/util/gcbf.m, scripts/plot/util/gcbo.m, scripts/plot/util/gcf.m, scripts/plot/util/gco.m, scripts/plot/util/ginput.m, scripts/plot/util/gnuplot_binary.in, scripts/plot/util/graphics_toolkit.m, scripts/plot/util/hdl2struct.m, scripts/plot/util/hggroup.m, scripts/plot/util/hold.m, scripts/plot/util/isaxes.m, scripts/plot/util/isfigure.m, scripts/plot/util/ishghandle.m, scripts/plot/util/ishold.m, scripts/plot/util/isprop.m, scripts/plot/util/linkprop.m, scripts/plot/util/meshgrid.m, scripts/plot/util/ndgrid.m, scripts/plot/util/newplot.m, scripts/plot/util/print.m, scripts/plot/util/printd.m, scripts/plot/util/private/__add_default_menu__.m, scripts/plot/util/private/__fltk_ginput__.m, scripts/plot/util/private/__fltk_print__.m, scripts/plot/util/private/__ghostscript__.m, scripts/plot/util/private/__gnuplot_get_var__.m, scripts/plot/util/private/__gnuplot_ginput__.m, scripts/plot/util/private/__gnuplot_has_feature__.m, scripts/plot/util/private/__gnuplot_has_terminal__.m, scripts/plot/util/private/__gnuplot_open_stream__.m, scripts/plot/util/private/__gnuplot_print__.m, scripts/plot/util/private/__gnuplot_version__.m, scripts/plot/util/private/__go_draw_axes__.m, scripts/plot/util/private/__go_draw_figure__.m, scripts/plot/util/private/__print_parse_opts__.m, scripts/plot/util/private/__tight_eps_bbox__.m, scripts/plot/util/refresh.m, scripts/plot/util/refreshdata.m, scripts/plot/util/saveas.m, scripts/plot/util/shg.m, scripts/plot/util/struct2hdl.m, scripts/plot/util/subplot.m: Moved from plot to subdir util. * etc/HACKING: Updated directory structure info. * scripts/Makefile.am, scripts/plot/appearance/module.mk, scripts/plot/draw/module.mk, scripts/plot/util/module.mk: Added new directories to build system.
author Rik <rik@octave.org>
date Fri, 04 Oct 2013 17:09:08 -0700
parents scripts/plot/contourc.m@56e72e8d1aba
children d63878346099
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/scripts/plot/draw/contourc.m	Fri Oct 04 17:09:08 2013 -0700
@@ -0,0 +1,171 @@
+## Copyright (C) 2003-2012 Shai Ayal
+##
+## 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{c}, @var{lev}] =} contourc (@var{z})
+## @deftypefnx {Function File} {[@var{c}, @var{lev}] =} contourc (@var{z}, @var{vn})
+## @deftypefnx {Function File} {[@var{c}, @var{lev}] =} contourc (@var{x}, @var{y}, @var{z})
+## @deftypefnx {Function File} {[@var{c}, @var{lev}] =} contourc (@var{x}, @var{y}, @var{z}, @var{vn})
+## Compute contour lines (isolines of constant Z value).
+##
+## The matrix @var{z} contains height values above the rectangular grid
+## determined by @var{x} and @var{y}.  If only a single input @var{z} is
+## provided then @var{x} is taken to be @code{1:rows (@var{z})} and @var{y} is
+## taken to be @code{1:columns (@var{z})}.
+##
+## The optional input @var{vn} is either a scalar denoting the number of
+## contour lines to compute or a vector containing the Z values where lines
+## will be computed.  When @var{vn} is a vector the number of contour lines
+## is @code{numel (@var{vn})}.  However, to compute a single contour line
+## at a given value use @code{@var{vn} = [val, val]}.  If @var{vn} is omitted
+## it defaults to 10.
+##
+## The return value @var{c} is a 2x@var{n} matrix containing the
+## contour lines in the following format
+##
+## @example
+## @group
+## @var{c} = [lev1, x1, x2, @dots{}, levn, x1, x2, ...
+##      len1, y1, y2, @dots{}, lenn, y1, y2, @dots{}]
+## @end group
+## @end example
+##
+## @noindent
+## in which contour line @var{n} has a level (height) of @var{levn} and
+## length of @var{lenn}.
+##
+## The optional return value @var{lev} is a vector with the Z values of
+## of the contour levels.
+##
+## Example:
+##
+## @example
+## @group
+## x = 0:2;
+## y = x;
+## z = x' * y;
+## contourc (x, y, z, 2:3)
+##    @result{}   2.0000   2.0000   1.0000   3.0000   1.5000   2.0000
+##         2.0000   1.0000   2.0000   2.0000   2.0000   1.5000
+## @end group
+## @end example
+## @seealso{contour, contourf, contour3, clabel}
+## @end deftypefn
+
+## Author: Shai Ayal <shaiay@users.sourceforge.net>
+
+function [c, lev] = contourc (varargin)
+
+  if (nargin < 1 || nargin > 4)
+    print_usage ();
+  endif
+
+  if (nargin == 1)
+    z = varargin{1};
+    x = 1:columns (z);
+    y = 1:rows (z);
+    vn = 10;
+  elseif (nargin == 2)
+    z = varargin{1};
+    x = 1:columns (z);
+    y = 1:rows (z);
+    vn = varargin{2};
+  elseif (nargin == 3)
+    x = varargin{1};
+    y = varargin{2};
+    z = varargin{3};
+    vn = 10;
+  elseif (nargin == 4)
+    x = varargin{1};
+    y = varargin{2};
+    z = varargin{3};
+    vn = varargin{4};
+  endif
+
+  if (! ismatrix (z) || ! ismatrix (x) || ! ismatrix (y))
+    error ("contourc: X, Y, and Z must be matrices");
+  endif
+
+  if (isscalar (vn))
+    vv = linspace (min (z(:)), max (z(:)), vn+2)(2:end-1);
+  else
+    vv = unique (sort (vn));
+  endif
+
+  if (isvector (x) && isvector (y))
+    cdat = __contourc__ (x(:)', y(:)', z, vv);
+  elseif (! any (bsxfun (@minus, x, x(1,:))(:))
+          && ! any (bsxfun (@minus, y, y(:,1))(:)))
+    ## x,y are uniform grid (such as from meshgrid)
+    cdat = __contourc__ (x(1,:), y(:,1)', z, vv);
+  else
+    ## Data is sampled over non-uniform mesh.
+    ## Algorithm calculates contours for uniform grid
+    ## and then interpolates values back to the non-uniform mesh.
+
+    ## Uniform grid for __contourc__.
+    [nr, nc] = size (z);
+    ii = 1:nc;
+    jj = 1:nr;
+
+    cdat = __contourc__ (ii, jj, z, vv);
+
+    ## Map the contour lines from index space (i,j)
+    ## back to the original grid (x,y)
+    i = 1;
+
+    while (i < columns (cdat))
+      clen = cdat(2, i);
+      idx = i + (1:clen);
+
+      ci = cdat(1, idx);
+      cj = cdat(2, idx);
+
+      ## Due to rounding errors, some elements of ci and cj
+      ## can fall out of the range of ii and jj and
+      ## interp2 would return NA for those values.
+      ## The permitted range is enforced here:
+
+      ci = max (ci, 1); ci = min (ci, nc);
+      cj = max (cj, 1); cj = min (cj, nr);
+
+      cdat(1, idx) = interp2 (ii, jj, x, ci, cj);
+      cdat(2, idx) = interp2 (ii, jj, y, ci, cj);
+
+      i += clen + 1;
+    endwhile
+  endif
+
+  if (nargout > 0)
+    c = cdat;
+    lev = vv;
+  endif
+
+endfunction
+
+
+%!test
+%! x = 0:2;
+%! y = x;
+%! z = x' * y;
+%! c_exp = [2, 1, 1, 2, 2, 3, 1.5, 2; 4, 2, 2, 1, 1, 2, 2, 1.5];
+%! lev_exp = [2 3];
+%! [c_obs, lev_obs] = contourc (x, y, z, 2:3);
+%! assert (c_obs, c_exp, eps);
+%! assert (lev_obs, lev_exp, eps);
+