From 8070dc963753142bb86c4ed698d91fd623ed28e7 Mon Sep 17 00:00:00 2001 From: ziejd2 Date: Thu, 28 Sep 2017 15:04:40 -0500 Subject: BNW using Octave instead of Matlab. This version of BNW should perform the same as the original version. The only difference is that it uses Octave instead of Matlab when running BayesNet Toolbox during parameter learning. I am calling this BNW_1.02. It can be accessed at: compbio.uthsc.edu/BNW_1.02 --- sourcecodes/bnt-master/KPMtools/polygon_centroid.m | 79 ++++++++++++++++++++++ 1 file changed, 79 insertions(+) create mode 100644 sourcecodes/bnt-master/KPMtools/polygon_centroid.m (limited to 'sourcecodes/bnt-master/KPMtools/polygon_centroid.m') diff --git a/sourcecodes/bnt-master/KPMtools/polygon_centroid.m b/sourcecodes/bnt-master/KPMtools/polygon_centroid.m new file mode 100644 index 00000000..f3e3947f --- /dev/null +++ b/sourcecodes/bnt-master/KPMtools/polygon_centroid.m @@ -0,0 +1,79 @@ +function [x0,y0] = centroid(x,y) +% CENTROID Center of mass of a polygon. +% [X0,Y0] = CENTROID(X,Y) Calculates centroid +% (center of mass) of planar polygon with vertices +% coordinates X, Y. +% Z0 = CENTROID(X+i*Y) returns Z0=X0+i*Y0 the same +% as CENTROID(X,Y). + +% Copyright (c) 1995 by Kirill K. Pankratov, +% kirill@plume.mit.edu. +% 06/01/95, 06/07/95 + +% Algorithm: +% X0 = Int{x*ds}/Int{ds}, where ds - area element +% so that Int{ds} is total area of a polygon. +% Using Green's theorem the area integral can be +% reduced to a contour integral: +% Int{x*ds} = -Int{x^2*dy}, Int{ds} = Int{x*dy} along +% the perimeter of a polygon. +% For a polygon as a sequence of line segments +% this can be reduced exactly to a sum: +% Int{x^2*dy} = Sum{ (x_{i}^2+x_{i+1}^2+x_{i}*x_{i+1})* +% (y_{i+1}-y_{i})}/3; +% Int{x*dy} = Sum{(x_{i}+x_{i+1})(y_{i+1}-y_{i})}/2. +% Similarly +% Y0 = Int{y*ds}/Int{ds}, where +% Int{y*ds} = Int{y^2*dx} = +% = Sum{ (y_{i}^2+y_{i+1}^2+y_{i}*y_{i+1})* +% (x_{i+1}-x_{i})}/3. + + % Handle input ...................... +if nargin==0, help centroid, return, end +if nargin==1 + sz = size(x); + if sz(1)==2 % Matrix 2 by n + y = x(2,:); x = x(1,:); + elseif sz(2)==2 % Matrix n by 2 + y = x(:,2); x = x(:,1); + else + y = imag(x); + x = real(x); + end +end + + % Make a polygon closed .............. +x = [x(:); x(1)]; +y = [y(:); y(1)]; + + % Check length ....................... +l = length(x); +if length(y)~=l + error(' Vectors x and y must have the same length') +end + + % X-mean: Int{x^2*dy} ................ +del = y(2:l)-y(1:l-1); +v = x(1:l-1).^2+x(2:l).^2+x(1:l-1).*x(2:l); +x0 = v'*del; + + % Y-mean: Int{y^2*dx} ................ +del = x(2:l)-x(1:l-1); +v = y(1:l-1).^2+y(2:l).^2+y(1:l-1).*y(2:l); +y0 = v'*del; + + % Calculate area: Int{y*dx} .......... +a = (y(1:l-1)+y(2:l))'*del; +tol= 2*eps; +if abs(a)