1 %% Copyright (c) 2011, INRA
2 %% 2003-2011, David Legland <david.legland@grignon.inra.fr>
3 %% 2011 Adapted to Octave by Juan Pablo Carbajal <carbajal@ifi.uzh.ch>
5 %% All rights reserved.
6 %% (simplified BSD License)
8 %% Redistribution and use in source and binary forms, with or without
9 %% modification, are permitted provided that the following conditions are met:
11 %% 1. Redistributions of source code must retain the above copyright notice, this
12 %% list of conditions and the following disclaimer.
14 %% 2. Redistributions in binary form must reproduce the above copyright notice,
15 %% this list of conditions and the following disclaimer in the documentation
16 %% and/or other materials provided with the distribution.
18 %% THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 %% AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 %% IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 %% ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22 %% LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 %% CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 %% SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 %% INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 %% CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 %% ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 %% POSSIBILITY OF SUCH DAMAGE.
30 %% The views and conclusions contained in the software and documentation are
31 %% those of the authors and should not be interpreted as representing official
32 %% policies, either expressed or implied, of copyright holder.
35 %% @deftypefn {Function File} {@var{circle} = } createCircle (@var{p1}, @var{p2}, @var{p3})
36 %% @deftypefnx {Function File} {@var{circle} = } createCircle (@var{p1}, @var{p2})
37 %% Create a circle from 2 or 3 points.
39 %% Creates the circle passing through the 3 given points.
40 %% C is a 1x3 array of the form: [XC YX R].
42 %% When two points are given, creates the circle whith center @var{p1} and passing
43 %% throuh the point @var{p2}.
45 %% Works also when input are point arrays the same size, in this case the
46 %% result has as many lines as the point arrays.
51 %% % Draw a circle passing through 3 points.
55 %% circle = createCircle(p1, p2, p3);
56 %% figure; hold on; axis equal; axis([0 50 0 50]);
57 %% drawPoint([p1 ; p2; p3]);
58 %% drawCircle(circle);
61 %% @seealso{circles2d, createDirectedCircle}
64 function circle = createCircle(varargin)
67 % inputs are the center and a point on the circle
72 r = hypot((p2(:,1)-x0), (p2(:,2)-y0));
75 % inputs are three points on the circle
80 % compute circle center
81 line1 = medianLine(p1, p2);
82 line2 = medianLine(p1, p3);
83 point = intersectLines(line1, line2);
88 r = hypot((p1(:,1)-x0), (p1(:,2)-y0));
91 % create array for returning result
97 %! privpath = [fileparts(which('geom2d_Contents')) filesep() 'private'];
100 %! addpath (privpath,'-end')
105 %! circle = createCircle(p1, p2, p3);
106 %! assertEqual(exp, circle);
107 %! circle = createCircle(p3, p1, p2);
108 %! assertEqual(exp, circle);
109 %! circle = createCircle(p2, p3, p1);
110 %! assertEqual(exp, circle);
111 %! rmpath (privpath);
114 %! addpath (privpath,'-end')
119 %! p1 = [p1; p1+10; p1+20; p1-5];
120 %! p2 = [p2; p2+10; p2+20; p2-5];
121 %! p3 = [p3; p3+10; p3+20; p3-5];
122 %! exp = repmat(exp, 4, 1) + [0 0 0;10 10 0;20 20 0;-5 -5 0];
123 %! circle = createCircle(p1, p2, p3);
124 %! assertEqual(exp, circle);
125 %! circle = createCircle(p3, p1, p2);
126 %! assertEqual(exp, circle);
127 %! circle = createCircle(p2, p3, p1);
128 %! assertEqual(exp, circle);
129 %! rmpath (privpath);