Add a useful package (from Source forge) for octave

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

diff --git a/octave_packages/geometry-1.5.0/geom2d/drawCircle.m b/octave_packages/geometry-1.5.0/geom2d/drawCircle.m
new file mode 100644 (file)
index 0000000..7563d56
--- /dev/null
+++ b/octave_packages/geometry-1.5.0/geom2d/drawCircle.m
@@ -0,0 +1,132 @@
+%% 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{h} = } drawCircle (@var{x0}, @var{y0}, @var{r})
+%% @deftypefnx {Function File} {@var{h} = } drawCircle (@var{circle})
+%% @deftypefnx {Function File} {@var{h} = } drawCircle (@var{center}, @var{radius})
+%% @deftypefnx {Function File} {@var{h} = } drawCircle (@dots{}, @var{nstep})
+%% @deftypefnx {Function File} {@var{h} = } drawCircle (@dots{}, @var{name}, @var{value})
+%% Draw a circle on the current axis
+%%
+%%   drawCircle(X0, Y0, R);
+%%   Draw the circle with center (X0,Y0) and the radius R. If X0, Y0 and R
+%%   are column vectors of the same length, draw each circle successively.
+%%
+%%   drawCircle(CIRCLE);
+%%   Concatenate all parameters in a Nx3 array, where N is the number of
+%%   circles to draw.
+%%
+%%   drawCircle(CENTER, RADIUS);
+%%   Specify CENTER as Nx2 array, and radius as a Nx1 array.
+%%
+%%   drawCircle(..., NSTEP);
+%%   Specify the number of edges that will be used to draw the circle.
+%%   Default value is 72, creating an approximation of one point for each 5
+%%   degrees.
+%%
+%%   drawCircle(..., NAME, VALUE);
+%%   Specifies plotting options as pair of parameters name/value. See plot
+%%   documentation for details.
+%%
+%%
+%%   H = drawCircle(...);
+%%   return handles to each created curve.
+%%
+%%   @seealso{circles2d, drawCircleArc, drawEllipse}
+%% @end deftypefn
+
+function varargout = drawCircle(varargin)
+
+  % process input parameters
+  var = varargin{1};
+  if size(var, 2) == 1
+      x0 = varargin{1};
+      y0 = varargin{2};
+      r  = varargin{3};
+      varargin(1:3) = [];
+      
+  elseif size(var, 2) == 2
+      x0 = var(:,1);
+      y0 = var(:,2);
+      r  = varargin{2};
+      varargin(1:2) = [];
+      
+  elseif size(var, 2) == 3
+      x0 = var(:,1);
+      y0 = var(:,2);
+      r  = var(:,3);
+      varargin(1) = [];
+  else
+      error('bad format for input in drawCircle');
+  end
+
+  % ensure each parameter is column vector
+  x0 = x0(:);
+  y0 = y0(:);
+  r = r(:);
+
+  % default number of discretization steps
+  N = 72;
+
+  % check if discretization step is specified
+  if ~isempty(varargin)
+      var = varargin{1};
+      if length(var)==1 && isnumeric(var)
+          N = round(var);
+          varargin(1) = [];
+      end
+  end
+
+  % parametrization variable for circle (use N+1 as first point counts twice)
+  t = linspace(0, 2*pi, N+1);
+  cot = cos(t);
+  sit = sin(t);
+
+  % empty array for graphic handles
+  h = zeros(size(x0));
+
+  % compute discretization of each circle
+  for i = 1:length(x0)
+      xt = x0(i) + r(i) * cot;
+      yt = y0(i) + r(i) * sit;
+
+      h(i) = plot(xt, yt, varargin{:});
+  end
+
+  if nargout > 0
+      varargout = {h};
+  end
+
+endfunction
+