CGAL 5.4  3D Spherical Geometry Kernel

SphericalKernel::GetEquation
Operations  
SphericalKernel::Circle_3  operator() (const SphericalKernel::Circular_arc_3 &a) 
Constructs the circle containing the arc.  
SphericalKernel::Circle_3  operator() (const SphericalKernel::Polynomials_for_circles_3 &p) 
Constructs a circle from an equation.  