function [xNew,yNew] = Centralize(x,y)
% x and y are column n-vectors that define the vertices of a polygon P.
% xNew and yNew are the vertices of a polygon obtained by translating
% P so that its centroid is at (0,0).
n = length(x);
% Compute the centroid...
xBar = sum(x)/n; yBar = sum(y)/n;
% Translate the polygon...
xNew = zeros(n,1); yNew = zeros(n,1);
for k= 1:n
xNew(k) = x(k)-xBar; yNew(k) = y(k)-yBar;
end