# Category: Directed graphs

Flow graph (mathematics)
A flow graph is a form of digraph associated with a set of linear algebraic or differential equations: "A signal flow graph is a network of nodes (or points) interconnected by directed branches, repre
Strong connectivity augmentation
Strong connectivity augmentation is a computational problem in the mathematical study of graph algorithms, in which the input is a directed graph and the goal of the problem is to add a small number o
Aczel's anti-foundation axiom
In the foundations of mathematics, Aczel's anti-foundation axiom is an axiom set forth by Peter Aczel, as an alternative to the axiom of foundation in Zermelo–Fraenkel set theory. It states that every
Quiver (mathematics)
In graph theory, a quiver is a directed graph where loops and multiple arrows between two vertices are allowed, i.e. a multidigraph. They are commonly used in representation theory: a representation V
Dependency graph
In mathematics, computer science and digital electronics, a dependency graph is a directed graph representing dependencies of several objects towards each other. It is possible to derive an evaluation
Skew-symmetric graph
In graph theory, a branch of mathematics, a skew-symmetric graph is a directed graph that is isomorphic to its own transpose graph, the graph formed by reversing all of its edges, under an isomorphism
Implication graph
In mathematical logic and graph theory, an implication graph is a skew-symmetric, directed graph G = (V, E) composed of vertex set V and directed edge set E. Each vertex in V represents the truth stat
Random surfing model
The random surfing model is a graph model which describes the probability of a random user visiting a web page. The model attempts to predict the chance that a random internet surfer will arrive at a
Table of vertex-symmetric digraphs
The best known vertex transitive digraphs (as of October 2008) in the directed Degree diameter problem are tabulated below.
Pre-topological order
In the field of computer science, a pre-topological order or pre-topological ordering of a directed graph is a linear ordering of its vertices such that if there is a directed path from vertex u to ve
Directed pseudoforest
No description available.
Polygraph (mathematics)
In mathematics, and particularly in category theory, a polygraph is a generalisation of a directed graph. It is also known as a computad. They were introduced as "polygraphs" by and as "computads" by
Network flow problem
In combinatorial optimization, network flow problems are a class of computational problems in which the input is a flow network (a graph with numerical capacities on its edges), and the goal is to con
Wait-for graph
A wait-for graph in computer science is a directed graph used for deadlock detection in operating systems and relational database systems. In computer science, a system that allows concurrent operatio
Why–because analysis
Why–because analysis (WBA) is a method for accident analysis. It is independent of application domain and has been used to analyse, among others, aviation-, railway-, marine-, and computer-related acc
De Bruijn graph
In graph theory, an n-dimensional De Bruijn graph of m symbols is a directed graph representing overlaps between sequences of symbols. It has mn vertices, consisting of all possible length-n sequences
Propositional directed acyclic graph
A propositional directed acyclic graph (PDAG) is a data structure that is used to represent a Boolean function. A Boolean function can be represented as a rooted, directed acyclic graph of the followi
Kautz graph
The Kautz graph is a directed graph of degree and dimension , which has vertices labeled by allpossible strings of length which are composed of characters chosen froman alphabet containing distinctsym
Transpose graph
In the mathematical and algorithmic study of graph theory, the converse, transpose or reverse of a directed graph G is another directed graph on the same set of vertices with all of the edges reversed
Directed acyclic graph
In mathematics, particularly graph theory, and computer science, a directed acyclic graph (DAG) is a directed graph with no directed cycles. That is, it consists of vertices and edges (also called arc
Strongly connected component
In the mathematical theory of directed graphs, a graph is said to be strongly connected if every vertex is reachable from every other vertex. The strongly connected components of an arbitrary directed
St-connectivity
In computer science, st-connectivity or STCON is a decision problem asking, for vertices s and t in a directed graph, if t is reachable from s. Formally, the decision problem is given by PATH = {⟨D, s
BEST theorem
In graph theory, a part of discrete mathematics, the BEST theorem gives a product formula for the number of Eulerian circuits in directed (oriented) graphs. The name is an acronym of the names of peop
Tournament (graph theory)
A tournament is a directed graph (digraph) obtained by assigning a direction for each edge in an undirected complete graph. That is, it is an orientation of a complete graph, or equivalently a directe
Cause–effect graph
No description available.
Semi-invariant of a quiver
In mathematics, given a quiver Q with set of vertices Q0 and set of arrows Q1, a representation of Q assigns a vector space Vi to each vertex and a linear map V(α): V(s(α)) → V(t(α)) to each arrow α,
New digraph reconstruction conjecture
The reconstruction conjecture of Stanisław Ulam is one of the best-known open problems in graph theory. Using the terminology of Frank Harary it can be stated as follows: If G and H are two graphs on
Feedback arc set
In graph theory and graph algorithms, a feedback arc set or feedback edge set in a directed graph is a subset of the edges of the graph that contains at least one edge out of every cycle in the graph.
Directed graph
In mathematics, and more specifically in graph theory, a directed graph (or digraph) is a graph that is made up of a set of vertices connected by directed edges, often called arcs.