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update Octave Project Developers copyright for the new year
In files that have the "Octave Project Developers" copyright notice,
update for 2021.
In all .txi and .texi files except gpl.txi and gpl.texi in the
doc/liboctave and doc/interpreter directories, change the copyright
to "Octave Project Developers", the same as used for other source
files. Update copyright notices for 2022 (not done since 2019). For
gpl.txi and gpl.texi, change the copyright notice to be "Free Software
Foundation, Inc." and leave the date at 2007 only because this file
only contains the text of the GPL, not anything created by the Octave
Project Developers.
Add Paul Thomas to contributors.in.
author | John W. Eaton <jwe@octave.org> |
---|---|
date | Tue, 28 Dec 2021 18:22:40 -0500 |
parents | 0a5b15007766 |
children | 597f3ee61a48 |
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######################################################################## ## ## Copyright (C) 1994-2022 The Octave Project Developers ## ## See the file COPYRIGHT.md in the top-level directory of this ## distribution or <https://octave.org/copyright/>. ## ## 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 ## <https://www.gnu.org/licenses/>. ## ######################################################################## ## -*- texinfo -*- ## @deftypefn {} {} image (@var{img}) ## @deftypefnx {} {} image (@var{x}, @var{y}, @var{img}) ## @deftypefnx {} {} image (@dots{}, "@var{prop}", @var{val}, @dots{}) ## @deftypefnx {} {} image ("@var{prop1}", @var{val1}, @dots{}) ## @deftypefnx {} {@var{h} =} image (@dots{}) ## Display a matrix as an indexed color image. ## ## The elements of @var{img} are indices into the current colormap. ## ## @var{x} and @var{y} are optional 2-element vectors, @w{@code{[min, max]}}, ## which specify the coordinates of the centers of the corner pixels. ## If a range is specified as @w{@code{[max, min]}} then the image will be ## reversed along that axis. For convenience, @var{x} and @var{y} may be ## specified as N-element vectors matching the length of the data in @var{img}. ## However, only the first and last elements will be used to determine the axis ## limits. ## ## Multiple property/value pairs may be specified for the image object, but ## they must appear in pairs. ## ## The optional return value @var{h} is a graphics handle to the image. ## ## Implementation Note: The origin (0, 0) for images is located in the ## upper left. For ordinary plots, the origin is located in the lower ## left. Octave handles this inversion by plotting the data normally, ## and then reversing the direction of the y-axis by setting the ## @code{ydir} property to @qcode{"reverse"}. This has implications whenever ## an image and an ordinary plot need to be overlaid. The recommended ## solution is to display the image and then plot the reversed ydata ## using, for example, @code{flipud (ydata)}. ## ## Calling Forms: The @code{image} function can be called in two forms: ## High-Level and Low-Level. When invoked with normal options, the High-Level ## form is used which first calls @code{newplot} to prepare the graphic figure ## and axes. When the only inputs to @code{image} are property/value pairs ## the Low-Level form is used which creates a new instance of an image object ## and inserts it in the current axes. ## ## Graphic Properties: The full list of properties is documented at ## @ref{Image Properties}. ## @seealso{imshow, imagesc, colormap} ## @end deftypefn function h = image (varargin) [hax, varargin, nargin] = __plt_get_axis_arg__ ("image", varargin{:}); chararg = find (cellfun ("isclass", varargin, "char"), 1, "first"); do_new = true; if (nargin == 0) img = get (0, "defaultimagecdata"); x = y = []; elseif (chararg == 1) ## Low-Level syntax do_new = false; x = y = img = []; idx = find (strcmpi (varargin, "cdata"), 1); if (idx) img = varargin{idx+1}; varargin(idx:idx+1) = []; endif idx = find (strcmpi (varargin, "xdata"), 1); if (idx) x = varargin{idx+1}; varargin(idx:idx+1) = []; endif idx = find (strcmpi (varargin, "ydata"), 1); if (idx) y = varargin{idx+1}; varargin(idx:idx+1) = []; endif elseif (nargin == 1 || chararg == 2) img = varargin{1}; x = y = []; elseif (nargin == 2 || chararg == 3) print_usage (); else x = varargin{1}; y = varargin{2}; img = varargin{3}; chararg = 4; endif if (iscomplex (img)) error ("image: IMG data can not be complex"); endif oldfig = []; if (! isempty (hax)) oldfig = get (0, "currentfigure"); endif unwind_protect if (do_new) hax = newplot (hax); elseif (isempty (hax)) hax = gca (); else hax = hax(1); endif htmp = __img__ (hax, do_new, x, y, img, varargin{chararg:end}); unwind_protect_cleanup if (! isempty (oldfig)) set (0, "currentfigure", oldfig); endif end_unwind_protect if (nargout > 0) h = htmp; endif endfunction ## Generic image creation. ## ## The axis values corresponding to the matrix elements are specified in ## @var{x} and @var{y}. function h = __img__ (hax, do_new, x, y, img, varargin) if (! isempty (img)) if (isempty (x)) xdata = []; else xdata = x([1, end])(:).'; # (:).' is a hack to guarantee row vector endif if (isempty (y)) ydata = []; else ydata = y([1, end])(:).'; endif if (numel (x) > 2 && numel (y) > 2) ## Test data for non-linear spacing which is unsupported tol = .01; # 1% tolerance. FIXME: this value was chosen without thought. dx = diff (x); dxmean = (max (x) - min (x)) / (numel (x) - 1); dx = abs ((abs (dx) - dxmean) / dxmean); dy = diff (y); dymean = (max (y) - min (y)) / (numel (y) - 1); dy = abs ((abs (dy) - dymean) / dymean); if (any (dx > tol) || any (dy > tol)) warning (["image: non-linear X, Y data is ignored. " ... "IMG will be shown with linear mapping"]); endif endif endif # ! isempty (img) if (do_new && ! ishold (hax)) ## Set axis properties for new images ## NOTE: Do this before calling __go_image__ so that image is not drawn ## once with default auto-scale axis limits and then a second time ## with tight axis limits. if (! isempty (img)) if (isempty (get (hax, "children"))) axis (hax, "tight"); endif if (ndims (img) == 3) if (isinteger (img)) mn = intmin (img); mx = intmax (img); set (hax, "clim", double ([mn, mx])); endif endif endif # ! isempty (img) set (hax, "view", [0, 90], "ydir", "reverse", "layer", "top", "box", "on"); endif # do_new h = __go_image__ (hax, "cdata", img, "xdata", xdata, "ydata", ydata, "cdatamapping", "direct", varargin{:}); if (do_new && ! ishold (hax) && ! isempty (img) && isscalar (get (hax, "children"))) ## Re-scale axis limits for an image in a new figure or axis. axis (hax, "tight"); endif endfunction %!demo %! clf; %! colormap (jet (21)); %! img = 1 ./ hilb (11); %! x = y = -5:5; %! subplot (2,2,1); %! h = image (x, y, img); %! ylabel ("limits = [-5.5, 5.5]"); %! title ("image (x, y, img)"); %! subplot (2,2,2); %! h = image (-x, y, img); %! title ("image (-x, y, img)"); %! subplot (2,2,3); %! h = image (x, -y, img); %! title ("image (x, -y, img)"); %! ylabel ("limits = [-5.5, 5.5]"); %! subplot (2,2,4); %! h = image (-x, -y, img); %! title ("image (-x, -y, img)"); ## test hidden properties x/ydatamode %!test <*42121> %! hf = figure ("visible", "off"); %! unwind_protect %! nx = 64; ny = 64; %! cdata = rand (ny, nx)*127; %! hi = image (cdata); # x/ydatamode is auto %! assert (get (hi, "xdata"), [1 nx]); %! assert (get (hi, "ydata"), [1 ny]); %! set (hi, "cdata", cdata(1:2:end, 1:2:end)); %! assert (get (hi, "xdata"), [1 nx/2]); %! assert (get (hi, "ydata"), [1 ny/2]); %! %! set (hi, "xdata", [10 100]); # xdatamode is now manual %! set (hi, "ydata", [10 1000]); # ydatamode is now manual %! set (hi, "cdata", cdata); %! assert (get (hi, "xdata"), [10 100]); %! assert (get (hi, "ydata"), [10 1000]); %! %! set (hi, "ydata", []); # ydatamode is now auto %! set (hi, "cdata", cdata(1:2:end, 1:2:end)); %! assert (get (hi, "xdata"), [10 100]); %! assert (get (hi, "ydata"), [1 ny/2]); %! unwind_protect_cleanup %! close (hf); %! end_unwind_protect ## FIXME: Need %!tests for linear %!error <IMG data can not be complex> image ([1, i])