octave-nkf: scripts/geometry/convhull.m annotate

annotate scripts/geometry/convhull.m @ 14138:72c96de7a403 stable

maint: update copyright notices for 2012

author	John W. Eaton <jwe@octave.org>
date	Mon, 02 Jan 2012 14:25:41 -0500
parents	7ff0bdc3dc4c
children	11949c9795a0

rev	line source
14138 72c96de7a403 maint: update copyright notices for 2012 John W. Eaton <jwe@octave.org> parents: 13746 diff changeset	1 ## Copyright (C) 2000-2012 Kai Habel
6823 9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	2 ##
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	3 ## This file is part of Octave.
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	4 ##
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	5 ## Octave is free software; you can redistribute it and/or modify it
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	6 ## under the terms of the GNU General Public License as published by
7016 93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6846 diff changeset	7 ## the Free Software Foundation; either version 3 of the License, or (at
93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6846 diff changeset	8 ## your option) any later version.
6823 9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	9 ##
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	10 ## Octave is distributed in the hope that it will be useful, but
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	11 ## WITHOUT ANY WARRANTY; without even the implied warranty of
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	13 ## General Public License for more details.
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	14 ##
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	15 ## You should have received a copy of the GNU General Public License
7016 93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6846 diff changeset	16 ## along with Octave; see the file COPYING. If not, see
93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6846 diff changeset	17 ## <http://www.gnu.org/licenses/>.
6823 9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	18
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	19 ## -- texinfo --
10793 be55736a0783 Grammarcheck the documentation from m-files. Rik <octave@nomad.inbox5.com> parents: 8920 diff changeset	20 ## @deftypefn {Function File} {@var{H} =} convhull (@var{x}, @var{y})
13746 7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	21 ## @deftypefnx {Function File} {@var{H} =} convhull (@var{x}, @var{y}, @var{options})
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	22 ## Compute the convex hull of the set of points defined by the
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	23 ## vectors @var{x} and @var{y}. The hull @var{H} is an index vector into
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	24 ## the set of points and specifies which points form the enclosing hull.
6823 9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	25 ##
13746 7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	26 ## An optional third argument, which must be a string or cell array of strings,
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	27 ## contains options passed to the underlying qhull command.
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	28 ## See the documentation for the Qhull library for details
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	29 ## @url{http://www.qhull.org/html/qh-quick.htm#options}.
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	30 ## The default option is @code{@{"Qt"@}}.
6823 9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	31 ##
13746 7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	32 ## If @var{options} is not present or @code{[]} then the default arguments are
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	33 ## used. Otherwise, @var{options} replaces the default argument list.
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	34 ## To append user options to the defaults it is necessary to repeat the
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	35 ## default arguments in @var{options}. Use a null string to pass no arguments.
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	36 ##
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	37 ## @seealso{convhulln, delaunay, voronoi}
6823 9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	38 ## @end deftypefn
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	39
6826 8618f29520c6 [project @ 2007-08-24 16:02:07 by jwe] jwe parents: 6823 diff changeset	40 ## Author: Kai Habel <kai.habel@gmx.de>
6823 9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	41
13746 7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	42 function H = convhull (x, y, options)
6823 9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	43
6826 8618f29520c6 [project @ 2007-08-24 16:02:07 by jwe] jwe parents: 6823 diff changeset	44 if (nargin != 2 && nargin != 3)
6823 9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	45 print_usage ();
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	46 endif
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	47
13746 7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	48 if (! (isvector (x) && isvector (y) && length (x) == length (y))
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	49 && ! size_equal (x, y))
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	50 error ("convhull: X and Y must be the same size");
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	51 elseif (nargin == 3 && ! (ischar (options) \|\| iscellstr (options)))
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	52 error ("convhull: OPTIONS must be a string or cell array of strings");
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	53 endif
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	54
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	55 if (nargin == 2)
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	56 i = convhulln ([x(:), y(:)]);
6823 9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	57 else
13746 7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	58 i = convhulln ([x(:), y(:)], options);
6823 9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	59 endif
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	60
6826 8618f29520c6 [project @ 2007-08-24 16:02:07 by jwe] jwe parents: 6823 diff changeset	61 n = rows (i);
6823 9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	62 i = i'(:);
6826 8618f29520c6 [project @ 2007-08-24 16:02:07 by jwe] jwe parents: 6823 diff changeset	63 H = zeros (n + 1, 1);
6823 9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	64
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	65 H(1) = i(1);
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	66 next_i = i(2);
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	67 i(2) = 0;
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	68 for k = 2:n
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	69 next_idx = find (i == next_i);
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	70
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	71 if (rem (next_idx, 2) == 0)
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	72 H(k) = i(next_idx);
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	73 next_i = i(next_idx - 1);
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	74 i(next_idx - 1) = 0;
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	75 else
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	76 H(k) = i(next_idx);
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	77 next_i = i(next_idx + 1);
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	78 i(next_idx + 1) = 0;
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	79 endif
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	80 endfor
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	81
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	82 H(n + 1) = H(1);
13746 7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	83
6823 9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	84 endfunction
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	85
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	86
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	87 %!demo
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	88 %! x = -3:0.05:3;
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	89 %! y = abs (sin (x));
9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	90 %! k = convhull (x, y);
13746 7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	91 %! plot (x(k),y(k),"r-;convex hull;", x,y,"b+;points;");
6823 9fddcc586065 [project @ 2007-08-24 08:27:27 by dbateman] dbateman parents: diff changeset	92 %! axis ([-3.05, 3.05, -0.05, 1.05]);
13746 7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	93
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	94 %!testif HAVE_QHULL
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	95 %! x = -3:0.5:3;
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	96 %! y = abs (sin (x));
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	97 %! assert (convhull (x, y), [1;7;13;12;11;10;4;3;2;1])
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	98
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	99 %% FIXME: Need input validation tests
7ff0bdc3dc4c Revamp geometry functions dependent on Qhull (Bug #34604, Bug #33346) Rik <octave@nomad.inbox5.com> parents: 12575 diff changeset	100

Mercurial > octave-nkf

annotate scripts/geometry/convhull.m @ 14138:72c96de7a403 stable