HYPERGRAPH

Hypergraph - A set of nodes (or vertices), say V, plus a set of edges, say E, such that each member of E is a subset of V. When each member of E has exactly 2 nodes, [V,E] is a graph . The hypergraph is a convenient mathematical way to describe relations that involve more than two objects (nodes). One special case is an IIS hypergraph: each node represents an inequality and each edge represents an IIS.