CGAL 5.4.4  2D and 3D Linear Geometry Kernel

AdaptableFunctor
(with three arguments)CGAL::Weighted_point_2<Kernel>
ComputePowerProduct_2
for the definition of power distance. Operations  
Comparison_result  operator() (const Kernel::Point_2 &p, const Kernel::Weighted_point_2 &q, const Kernel::Weighted_point_2 &r) 
compares the power distance between p and q to the power distance between p and r .  