intersectionGraph Class Reference
[Graph series]

k-subset intersection graphs with cardinality restrictions on the intersection of adjacent subsets More...

#include <sparseGraph.h>

Inheritance diagram for intersectionGraph:

sparseGraph abstractGraph abstractMixedGraph managedObject goblinRootObject

Public Member Functions

 intersectionGraph (TNode groundSetCardinality, TNode subsetCardinality, TNode minimumIntersection, TNode maximumIntersection, goblinController &_CT=goblinDefaultContext) throw ()

Detailed Description

k-subset intersection graphs with cardinality restrictions on the intersection of adjacent subsets


Constructor & Destructor Documentation

intersectionGraph TNode  groundSetCardinality,
TNode  subsetCardinality,
TNode  minimumIntersection,
TNode  maximumIntersection,
goblinController _CT = goblinDefaultContext
throw ()
 

k-subset intersection graphs with cardinality restrictions on the intersection of adjacent subsets

Parameters:
groundSetCardinality The ground set cardinality
subsetCardinality The subset cardinality
minimumIntersection A lower bound on the intersection cardinality of adjacent subsets
maximumIntersection An upper bound on the intersection cardinality of adjacent subsets
_CT The controller object to manage the created graph
The node set of this graph consists from all subsets of a certain ground set with a given subsetCardinality. Of the ground set, only the groundSetCardinality is specified. Two graph nodes are adjacent if the intersection cardinality of the corresponding subsets is in the range [minimumIntersection,maximumIntersection].

The drawing shows the nodes on concentric circles with node indices increasing from the center point to the exterior circle. The nodes on the k-th circle represent the subset which can be built from the first subsetCardinality + k ground set elements - actually containing the k-th element.

This construction covers several known graph classes:

  • Complete graphs, taking minimumIntersection = maximumIntersection = 0 and subsetCardinality = 1. But prefer denseGraph for its efficent data structures.
  • Triangular graphs, taking minimumIntersection = maximumIntersection = 1 and subsetCardinality = 2. But prefer triangularGraph to obtain symmetric drawings.
  • Kneser graphs, taking minimumIntersection = maximumIntersection = 0
  • Generalized Kneser graphs, taking minimumIntersection = 0
  • Johnson graphs, taking minimumIntersection = maximumIntersection = subsetCardinality-1