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# areIsomorphic -- determines whether two graphs are isomorphic

- Usage:
    `b = areIsomorphic(G, H)`
    `G == H`
    `b = areIsomorphic(S, T)`
    `b = areIsomorphic(S, H)`
    `S == H`
    `b = areIsomorphic(G, T)`
    `G == T`
- Inputs:
  - G, a graph,
  - H, a graph,
  - S, a string,
  - T, a string,
- Outputs:
  - b, a Boolean value, whether the two graphs are isomorphic

## Description

A very efficient method for determining whether two graphs (of the same format) are isomorphic.

    i1 : R = QQ[a..e];

    i2 : areIsomorphic(cycle R, graph {a*c, c*e, e*b, b*d, d*a})

    o2 = true

    i3 : areIsomorphic(cycle R, completeGraph R)

    o3 = false

    i4 : cycle R == "Dhc"

    o4 = true

## See also

- Example: Checking for isomorphic graphs
- removeIsomorphs -- removes all isomorphs from a list of graphs

## Ways to use areIsomorphic:

- `areIsomorphic(Graph,Graph)`
- `areIsomorphic(Graph,String)`
- `areIsomorphic(String,Graph)`
- `areIsomorphic(String,String)`

## For the programmer

The object areIsomorphic is a method function.

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/Nauty.m2:639:0.