Add a useful package (from Source forge) for octave

[CreaPhase.git] / octave_packages / geometry-1.5.0 / geom2d / isPointOnLine.m

diff --git a/octave_packages/geometry-1.5.0/geom2d/isPointOnLine.m b/octave_packages/geometry-1.5.0/geom2d/isPointOnLine.m
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+++ b/octave_packages/geometry-1.5.0/geom2d/isPointOnLine.m
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+%% Copyright (c) 2011, INRA
+%% 2003-2011, David Legland <david.legland@grignon.inra.fr>
+%% 2011 Adapted to Octave by Juan Pablo Carbajal <carbajal@ifi.uzh.ch>
+%%
+%% All rights reserved.
+%% (simplified BSD License)
+%%
+%% Redistribution and use in source and binary forms, with or without
+%% modification, are permitted provided that the following conditions are met:
+%%
+%% 1. Redistributions of source code must retain the above copyright notice, this
+%%    list of conditions and the following disclaimer.
+%%     
+%% 2. Redistributions in binary form must reproduce the above copyright notice, 
+%%    this list of conditions and the following disclaimer in the documentation
+%%    and/or other materials provided with the distribution.
+%%
+%% THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+%% AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+%% IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+%% ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+%% LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
+%% CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+%% SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+%% INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+%% CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+%% ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+%% POSSIBILITY OF SUCH DAMAGE.
+%%
+%% The views and conclusions contained in the software and documentation are
+%% those of the authors and should not be interpreted as representing official
+%% policies, either expressed or implied, of copyright holder.
+
+%% -*- texinfo -*-
+%% @deftypefn {Function File} {@var{b} = } isPointOnLine (@var{point}, @var{line})
+%% Test if a point belongs to a line
+%%
+%%   B = isPointOnLine(POINT, LINE)
+%%   with POINT being [xp yp], and LINE being [x0 y0 dx dy].
+%%   Returns 1 if point lies on the line, 0 otherwise.
+%%
+%%   If POINT is an N*2 array of points, B is a N*1 array of booleans.
+%%
+%%   If LINE is a N*4 array of line, B is a 1*N array of booleans.
+%%
+%%   @seealso {lines2d, points2d, isPointOnEdge, isPointOnRay, angle3Points}
+%% @end deftypefn
+
+function b = isPointOnLine(point, line, varargin)
+ 
+  % extract computation tolerance
+  tol = 1e-14;
+  if ~isempty(varargin)
+      tol = varargin{1};
+  end
+
+  % number of lines and of points
+  Nl = size(line, 1);
+  Np = size(point, 1);
+
+  % adapt the size of inputs
+  x0 = repmat(line(:,1)', Np, 1);
+  y0 = repmat(line(:,2)', Np, 1);
+  dx = repmat(line(:,3)', Np, 1);
+  dy = repmat(line(:,4)', Np, 1);
+  xp = repmat(point(:,1), 1, Nl);
+  yp = repmat(point(:,2), 1, Nl);
+
+  % test if lines are colinear
+  b = abs((xp-x0).*dy-(yp-y0).*dx)./hypot(dx, dy) < tol;
+
+endfunction