CGAL 5.5.2  dD Geometry Kernel

Operations  
template<class ForwardIterator >  
Oriented_side  operator() (ForwardIterator first, ForwardIterator last, const Kernel_d::Point_d &p) 
returns the relative position of point p to the oriented sphere defined by the points in A = tuple [first,last) The order of the points in \( A\) is important, since it determines the orientation of the implicitly constructed sphere. More...  
Oriented_side Kernel_d::Side_of_oriented_sphere_d::operator()  (  ForwardIterator  first, 
ForwardIterator  last,  
const Kernel_d::Point_d &  p  
) 
returns the relative position of point p
to the oriented sphere defined by the points in A = tuple [first,last)
The order of the points in \( A\) is important, since it determines the orientation of the implicitly constructed sphere.
If the points in \( A\) are positively oriented, the positive side is the bounded interior of the sphere.
A
contains \( d+1\) points in \( d\)space. ForwardIterator  has Kernel_d::Point_d as value type. 