Directed graph - Revision history

Karl Jones at 11:52, 28 May 2016

2016-05-28T11:52:49Z

Karl Jones at 11:51, 28 May 2016

2016-05-28T11:51:36Z

Karl Jones: /* See also */

2016-05-07T18:29:01Z

‎See also

Karl Jones: /* External links */

2016-04-23T11:13:25Z

‎External links

Karl Jones: Created page with "In mathematics, and more specifically in graph theory, a '''directed graph''' (or '''digraph''') is a graph (discrete mathematics), or set of vertices connected by..."

2016-03-10T15:58:01Z

Created page with "In mathematics, and more specifically in graph theory, a '''directed graph''' (or '''digraph''') is a graph (discrete mathematics), or set of vertices connected by..."

New page

In [[mathematics]], and more specifically in [[graph theory]], a '''directed graph''' (or '''digraph''') is a [[graph (discrete mathematics)]], or set of vertices connected by edges, where the edges have a direction associated with them.

== Definition ==

In formal terms, a directed graph is an ordered pair G = (V, A) (sometimes G = (V, E)) where:

* V is a set whose elements are called vertices, nodes, or points;
* A is a set of ordered pairs of vertices, called arrows, directed edges (sometimes simply edges with the corresponding set named E instead of A), directed arcs, or directed lines.

It differs from an ordinary or undirected graph, in that the latter is defined in terms of unordered pairs of vertices, which are usually called edges, arcs, or lines.

A directed graph is called a simple digraph if it has no multiple arrows (two or more edges that connect the same two vertices in the same direction) and no loops (edges that connect vertices to themselves).

A directed graph is called a directed multigraph or multidigraph if it may have multiple arrows (and sometimes loops).

In the latter case the arrow set forms a multiset, rather than a set, of ordered pairs of vertices.

== See also ==

* [[Graph (discrete mathematics)]]
* [[Graph theory]]
* [[Mathematics]]

== External links ==

* [https://en.wikipedia.org/wiki/Directed_graph Directed graph] @ Wikipedia

← Older revision		Revision as of 11:51, 28 May 2016
Line 1:		Line 1:
−	In [[mathematics]], and more specifically in [[graph theory]], a '''directed graph''' (or '''digraph''') is a [[graph (discrete mathematics)]], or set of vertices connected by edges, where the edges have a direction associated with them.	+	[[File:Directed-graph-4-node-digraph.png\|thumb\|Simple directed graph.]]In [[mathematics]], and more specifically in [[graph theory]], a '''directed graph''' (or '''digraph''') is a [[graph (discrete mathematics)]], or set of vertices connected by edges, where the edges have a direction associated with them.

	== Definition ==		== Definition ==

← Older revision		Revision as of 11:13, 23 April 2016
Line 25:		Line 25:

	* [https://en.wikipedia.org/wiki/Directed_graph Directed graph] @ Wikipedia		* [https://en.wikipedia.org/wiki/Directed_graph Directed graph] @ Wikipedia
		+
		+	[[Category:Graph theory]]
		+	[[Category:Mathematics]]

@@ Line 18: / Line 18: @@
 == See also ==
+* [[Coates graph]]
 * [[Game tree]]
 * [[Graph (discrete mathematics)]]
 * [[Graph theory]]
 * [[Mathematics]]
 ==  External links ==