`isisomorphic`

Tests whether two graphs have the same structure.

Category: Mathematics > Graph and Network Algorithms

Syntax

tf = isisomorphic(G1, G2)

Returns true if the graphs are isomorphic.

Description

Two graphs are isomorphic when the nodes of one can be renamed so that its edges become exactly the edges of the other. Node labels do not matter, only the pattern of connections. Different numbers of nodes or edges, or different degree counts, rule out isomorphism immediately.

To find the renaming itself, use isomorphism.

Input arguments

G1, G2: Two graphs of the same kind: both graph or both digraph.

Output arguments

tf: Logical scalar.

Example

Same shape, different labels

A = graph([1 2], [2 3]);
B = graph([1 3], [3 2]);
C = graph([1 2 3], [2 3 1]);
isisomorphic(A, B)
isisomorphic(A, C)

Output

ans = logical
   1
ans = logical
   0

isisomorphic