graph theory In mathematics, graph theory is the study of ''graphs'', which are mathematical structures used to model pairwise relations between objects. A graph in this context is made up of '' vertices'' (also called ''nodes'' or ''points'') which are conne ...

, a BF-graph is a type of directed hypergraph where each

hyperedge This is a glossary of graph theory. Graph theory is the study of graphs, systems of nodes or vertices connected in pairs by lines or edges. Symbols A B ...

is directed either to one particular

vertex Vertex, vertices or vertexes may refer to: Science and technology Mathematics and computer science *Vertex (geometry), a point where two or more curves, lines, or edges meet *Vertex (computer graphics), a data structure that describes the position ...

or away from one particular vertex. In a directed hypergraph, each hyperedge may be directed away from some of its vertices (its ''tails'') and towards some others of its vertices (its ''heads''). A hyperedge that is directed to a single head vertex, and away from all its other vertices, is called a ''B''-arch. Symmetrically, a hyperedge that is directed away from a single tail vertex, and towards all its other vertices, is called an ''F''-arc. A hypergraph with only B-arcs is a B-graph and a hypergraph with only F-arcs is a F-graph.

References

* * Hypergraphs {{graph-stub