eliminationordering : keyword option of the form eliminationordering=true or eliminationordering=false.

Specifies whether an elimination ordering should be returned when G is chordal. The default is false.

usecached : keyword option of the form usecached=true or usecached=false.

Specifies whether previously stored information should be used, if available. The default is true.

The IsChordal(G) command returns true if G is a chordal graph and false otherwise.

An undirected graph G is chordal if every cycle of length 4 or more has a chord, that is, an edge that is not part of the cycle but connects two vertices of the cycle.

Every interval graph is a chordal graph.

Every split graph is a chordal graph.

$\mathrm{with}\left(\mathrm{GraphTheory}\right)\:$

$\mathrm{C4}≔\mathrm{CycleGraph}\left(4\right)$

$\mathrm{C4}≔\mathrm{Graph\; 1:\; an\; undirected\; graph\; with\; 4\; vertices\; and\; 4\; edge(s)}$

$\mathrm{IsChordal}\left(\mathrm{C4}\right)$

$\mathrm{false}$

$\mathrm{K4}≔\mathrm{CompleteGraph}\left(4\right)$

$\mathrm{K4}≔\mathrm{Graph\; 2:\; an\; undirected\; graph\; with\; 4\; vertices\; and\; 6\; edge(s)}$

$\mathrm{IsChordal}\left(\mathrm{K4}\right)$

$\mathrm{true}$

$P≔\mathrm{SpecialGraphs}:-\mathrm{PetersenGraph}\left(\right)$

$P≔\mathrm{Graph\; 3:\; an\; undirected\; graph\; with\; 10\; vertices\; and\; 15\; edge(s)}$

$\mathrm{IsChordal}\left(P\right)$

$\mathrm{false}$

The GraphTheory[IsChordal] command was introduced in Maple 2022.

For more information on Maple 2022 changes, see Updates in Maple 2022.