isdag

Determine if graph is acyclic

Syntax

tf = isdag(G)

Description

tf = isdag(G) returns logical 1 (true) if G is a directed acyclic graph; otherwise, it returns logical 0 (false).

Examples

Determine if Directed Graph is Acyclic

Create and plot a directed graph, and then test the graph to determine if it is acyclic.

s = [1 1 2 2 3 3 4 4 4 5];
t = [2 3 4 5 6 7 8 9 10 4];
G = digraph(s,t)

G = 
  digraph with properties:

    Edges: [10×1 table]
    Nodes: [10×0 table]

plot(G)

tf = isdag(G)

tf = logical
   1

Input Arguments

G — Input graph

digraph object

Input graph, specified as a digraph object. Use digraph to create a directed graph object.

Example: G = digraph([1 2],[2 3])

More About

Directed Acyclic Graph (DAG)

A directed graph is acyclic if it contains no cycles. That is, starting at any node in the graph, no sequence of edges exists that can be followed to loop back to that starting node. As a result, directed acyclic graphs do not contain any self-loops.

Version History

Introduced in R2015b