In the mathematical discipline of graph theory, a graph C is a covering graph of another graph G if there is a covering map from the vertex set of C to the vertex set of G. A covering map f is a surjection and a local isomorphism: the neighbourhood of a v vertex in C is mapped bijectively onto the neighbourhood of f(v) in G.
The term lift is often used synonymous for a covering graph of a connected graph.
Note that a covering in graph theory may also refer to an unrelated concept, a subset of vertices that touches all edges.
Read more about Covering Graph: Definition, Examples, Double Cover, Universal Cover, Voltage Graphs
Famous quotes containing the words covering and/or graph:
“Three forms I see on stretchers lying, brought out there untended
lying,
Over each the blanket spread, ample brownish woolen blanket,
Gray and heavy blanket, folding, covering all.”
—Walt Whitman (1819–1892)
“In this Journal, my pen is a delicate needle point, tracing out a graph of temperament so as to show its daily fluctuations: grave and gay, up and down, lamentation and revelry, self-love and self-disgust. You get here all my thoughts and opinions, always irresponsible and often contradictory or mutually exclusive, all my moods and vapours, all the varying reactions to environment of this jelly which is I.”
—W.N.P. Barbellion (1889–1919)