--- /dev/null
+## Copyright (C) 2000-2012 Paul Kienzle
+##
+## 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 {Command} {} demo @var{name}
+## @deftypefnx {Command} {} demo @var{name} @var{n}
+## @deftypefnx {Function File} {} demo ('@var{name}')
+## @deftypefnx {Function File} {} 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.
+##
+## Examples are stored in the script file, or in a file with the same
+## name but no extension located on Octave's load path. To keep examples
+## separate from regular script code, all lines are prefixed by @code{%!}. Each
+## example must also be introduced by the keyword '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)
+## %! %-------------------------------------------------
+## %! % 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 a simple
+## comment at the end suffices for labeling what is being shown. It is
+## generally not necessary to use @code{disp} or @code{printf} within the demo.
+##
+## Demos are run in a 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 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.
+##
+## Also, because demo evaluates within a function context, you cannot
+## define new functions inside a demo. If you must have function blocks,
+## rather than just anonymous functions or inline functions, you will have to
+## use @code{eval(example('function',n))} to see them. Because eval only
+## evaluates one line, or one statement if the statement crosses
+## multiple lines, you must wrap your demo in "if 1 <demo stuff> endif"
+## with the 'if' on the same line as 'demo'. For example:
+##
+## @example
+## @group
+## %!demo if 1
+## %! function y=f(x)
+## %! y=x;
+## %! endfunction
+## %! f(3)
+## %! endif
+## @end group
+## @end example
+##
+## @seealso{test, example}
+## @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)
+
+ if (nargin < 1 || nargin > 2)
+ print_usage ();
+ endif
+
+ if (nargin < 2)
+ n = 0;
+ elseif (ischar (n))
+ n = str2double (n);
+ endif
+
+ [code, idx] = test (name, "grabdemo");
+ if (isempty (idx))
+ warning ("no demo available for %s", name);
+ return;
+ elseif (n >= length (idx))
+ warning ("only %d demos available for %s", length (idx) - 1, name);
+ return;
+ endif
+
+ if (n > 0)
+ doidx = n;
+ else
+ doidx = 1:length(idx)-1;
+ endif
+ for i = 1:length (doidx)
+ ## Pause between demos
+ if (i > 1)
+ input ("Press <enter> to continue: ", "s");
+ endif
+
+ ## Process each demo without failing
+ try
+ block = code(idx(doidx(i)):idx(doidx(i)+1)-1);
+ ## FIXME: need to check for embedded test functions, which cause
+ ## segfaults, until issues with subfunctions in functions are resolved.
+ embed_func = regexp (block, '^\s*function ', 'once', 'lineanchors');
+ if (isempty (embed_func))
+ ## Use an environment without variables
+ eval (cstrcat ("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__;
+ else
+ error (["Functions embedded in %!demo blocks are not allowed.\n", ...
+ "Use the %!function/%!endfunction syntax instead to define shared functions for testing.\n"]);
+ endif
+ 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
+
+%!demo
+%! t=0:0.01:2*pi; x = sin(t);
+%! plot (t,x)
+%! %-------------------------------------------------
+%! % the figure window shows one cycle of a sine wave
+
+%!error demo ();
+%!error demo (1, 2, 3);
git://git.creatis.insa-lyon.fr / CreaPhase.git / blobdiff