Mercurial > octave-libtiff
view scripts/testfun/demo.m @ 30564:796f54d4ddbf stable
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 | 7854d5752dd2 |
children |
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######################################################################## ## ## Copyright (C) 2000-2022 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 {} {} demo @var{name} ## @deftypefnx {} {} demo @var{name} @var{n} ## @deftypefnx {} {} demo ("@var{name}") ## @deftypefnx {} {} demo ("@var{name}", @var{n}) ## ## Run example code block @var{n} associated with the function @var{name}. ## ## If @var{n} is not specified, all examples are run. ## ## The preferred location for example code blocks is embedded within the script ## m-file immediately following the code that it exercises. Alternatively, ## the examples may be stored in a file with the same name but no extension ## located on Octave's load path. To separate examples from regular script ## code all lines are prefixed by @code{%!}. Each example must also be ## introduced by the keyword @qcode{"demo"} flush left to the prefix with no ## intervening spaces. The remainder of the example can contain arbitrary ## Octave code. For example: ## ## @example ## @group ## %!demo ## %! t = 0:0.01:2*pi; ## %! x = sin (t); ## %! plot (t, x); ## %! title ("one cycle of a sine wave"); ## %! #------------------------------------------------- ## %! # the figure window shows one cycle of a sine wave ## @end group ## @end example ## ## Note that the code is displayed before it is executed so that a simple ## comment at the end suffices for labeling what is being shown. For plots, ## labeling can also be done with @code{title} or @code{text}. It is generally ## @strong{not} necessary to use @code{disp} or @code{printf} within the demo. ## ## Demos are run in a stand-alone function environment with no access to ## external variables. This means that every demo must have separate ## initialization code. Alternatively, all demos can be combined into a single ## large demo with the code ## ## @example ## %! input ("Press <enter> to continue: ", "s"); ## @end example ## ## @noindent ## between the sections, but this usage is discouraged. Other techniques to ## avoid multiple initialization blocks include using multiple plots with a new ## @code{figure} command between each plot, or using @code{subplot} to put ## multiple plots in the same window. ## ## Finally, because @code{demo} evaluates within a function context it is not ## possible to define new functions within the code. Anonymous functions make ## a good substitute in most instances. If function blocks @strong{must} be ## used then the code @code{eval (example ("function", n))} will allow Octave ## to see them. This has its own problems, however, as @code{eval} only ## evaluates one line or statement at a time. In this case the function ## declaration must be wrapped with @qcode{"if 1 <demo stuff> endif"} where ## @qcode{"if"} is on the same line as @qcode{"demo"}. For example: ## ## @example ## @group ## %!demo if 1 ## %! function y = f(x) ## %! y = x; ## %! endfunction ## %! f(3) ## %! endif ## @end group ## @end example ## ## @seealso{rundemos, example, test} ## @end deftypefn ## FIXME: modify subplot so that gnuplot_has_multiplot == 0 causes it to ## use the current figure window but pause if not plotting in the ## first subplot. function demo (name, n = 0) if (nargin < 1) print_usage (); endif if (ischar (n)) n = str2double (n); endif if (! (isreal (n) && isscalar (n) && n == fix (n))) error ("demo: N must be a scalar integer"); endif ## Paging causes Qt graphics to hang on some demos. page_screen_output (false, "local"); [code, idx] = test (name, "grabdemo"); if (idx == -1) warning ("demo: no function %s found", name); return; elseif (isempty (idx)) warning ("demo: no demo available for %s", name); return; elseif (n >= length (idx)) warning ("demo: only %d demos available for %s", length (idx) - 1, name); return; endif if (n > 0) doidx = n; else doidx = 1:(length (idx) - 1); endif clear_figures (); for i = 1:length (doidx) ## Pause between demos if (i > 1) input ("Press <enter> to continue: ", "s"); clear_figures (); endif ## Process each demo without failing try block = code(idx(doidx(i)):idx(doidx(i)+1)-1); ## Use an environment without variables eval (["function __demo__ ()\n" block "\nendfunction"]); ## Display the code that will be executed before executing it printf ("%s example %d:%s\n\n", name, doidx(i), block); __demo__; catch ## Let the programmer know which demo failed. printf ("%s example %d: failed\n%s\n", name, doidx(i), lasterr ()); end_try_catch clear __demo__; endfor endfunction function clear_figures () ## Prevent proliferation of figure windows. If any figure windows exist, ## close all but one and clear the one remaining. figs = __go_figure_handles__ (); if (! isempty (figs)) if (numel (figs) > 1) figs = sort (figs); figs(1) = []; close (figs); endif clf ("reset"); endif endfunction %!demo %! t = 0:0.01:2*pi; %! x = sin (t); %! plot (t, x); %! title ("one cycle of a sine wave"); %! #------------------------------------------------- %! # the figure window shows one cycle of a sine wave %!error <Invalid call> demo () %!error <N must be a scalar integer> demo ("demo", {1}) %!error <N must be a scalar integer> demo ("demo", ones (2,2)) %!error <N must be a scalar integer> demo ("demo", 1.5) %!warning <no function .* found> demo ("_%NOT_A_FUNCTION%_"); %!warning <only 1 demos available for demo> demo ("demo", 10);