Classifier

A classifier represents an equivalence relation among the objects of a space. Operations explicate the predicate, return the class of a given object, and return all classes.

Implementations:

• Classifier_Explicit
  User explicitly specifies classes.
• Classifier_First_N
  Similar to Classifier_Transitive, but only builds groups of maximum size n, rather than the full transitive closure.
• Classifier_Transitive
  Groups objects into equivalence classes by transitively following an equivalence predicate (Space_Predicate) through an Ngraph.

• add_class: Classifier_Explicit . Space -> void
  Explicitly adds the class to the set of equivalence classes.
• classes: Classifier -> Classes
  Returns all classes.
• classify: Classifier . Space -> void
  Builds the classifier on the space.
• class_of: Classifier . Obj -> Space
  Returns the class (a space) of the object.
• space: Classifier -> Space
  Returns the classified space.