Objects from the Class
Objects can be created by calls of the form new("EllipticalSymmetry").
  More frequently they are created via the generating function 
  EllipticalSymmetry. Elliptical symmetry for instance leads to 
  a simplification for the computation of optimally robust influence curves.Extends
Class "DistributionSymmetry", directly.
Class "Symmetry", by class "DistributionSymmetry".concept
- elliptical symmetry
 - symmetry