planar matroid
Смотреть что такое "planar matroid" в других словарях:
Matroid — In combinatorics, a branch of mathematics, a matroid ( /ˈmeɪ … Wikipedia
Tutte polynomial — This article is about the Tutte polynomial of a graph. For the Tutte polynomial of a matroid, see Matroid. The polynomial x4 + x3 + x2y is the Tutte polynomial of the Bull graph. The red line shows the intersection with the plane … Wikipedia
Duality (mathematics) — In mathematics, a duality, generally speaking, translates concepts, theorems or mathematical structures into other concepts, theorems or structures, in a one to one fashion, often (but not always) by means of an involution operation: if the dual… … Wikipedia
Dual graph — G′ is the dual graph of G In mathematics, the dual graph of a given planar graph G is a graph which has a vertex for each plane region of G, and an edge for each edge in G joining two neighboring regions, for a certain embedding of G. The term… … Wikipedia
K-set (geometry) — In discrete geometry, a k set of a finite point set S in the Euclidean plane is a subset of k elements of S that can be strictly separated from the remaining points by a line. More generally, in Euclidean space of higher dimensions, a k set of a… … Wikipedia
Arboricity — The arboricity of an undirected graph is the minimum number of forests into which its edges can be partitioned. Equivalently it is the minimum number of spanning trees needed to cover all the edges of the graph.ExampleThe figure shows the… … Wikipedia
Wheel graph — infobox graph name = Wheel graph image caption = Several examples of wheel graphs vertices = n edges = 2( n − 1) chromatic number = 3 if n is odd 4 if n is even chromatic index = In the mathematical discipline of graph theory, a wheel graph W n… … Wikipedia
Pseudoforest — A 1 forest (a maximal pseudoforest), formed by three 1 trees In graph theory, a pseudoforest is an undirected graph[1] in which every connected component has at most one cycle. That is, it is a system of vertices and edges connecting pairs of ve … Wikipedia
Greedoid — In combinatorics, a greedoid is a type of set system. It arises from the notion of the matroid, which was originally introduced by Whitney in 1935 to study planar graphs and was later used by Edmonds to characterize a class of optimization… … Wikipedia
Edge coloring — A 3 edge coloring of the Desargues graph. In graph theory, an edge coloring of a graph is an assignment of “colors” to the edges of the graph so that no two adjacent edges have the same color. For example, the figure to the right shows an edge… … Wikipedia
Minor (graph theory) — In graph theory, an undirected graph H is called a minor of the graph G if H is isomorphic to a graph that can be obtained by zero or more edge contractions on a subgraph of G. The theory of graph minors began with Wagner s theorem that a graph… … Wikipedia
