By default, graphs in Maple 2017 are drawn using a grayscale color scheme.

You can now control many aspects of how a graph is drawn.  The colors, line weights, and font choices can be specified with the stylesheet option.  For details, see Graph Drawing Options.

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

You can use the graph drawing settings from previous versions of Maple by specifying stylesheet="legacy".  Animations and 3-D graph renderings currently do not support the stylesheet option.

The new commands GraphTheory[CanonicalGraph], GraphTheory[Eccentricity], and GraphTheory[Radius] enable the construction of new graph normal forms and the computation of quantities from graphs.

The CanonicalGraph command constructs a version of the input graph in which the vertices have been reordered such that the resulting graph is in a canonical form. The output is canonical in the sense that any two graphs $G$ and $H$ are isomorphic if and only if $\mathrm{AdjacencyMatrix}\left(\mathrm{CanonicalGraph}\left(G\right)\right) \=\mathrm{AdjacencyMatrix}\left(\mathrm{CanonicalGraph}\left(H\right)\right)$. In this example, the Foster cage graph and the Meringer graph serve as examples of graphs which are both cage graphs with the same number of vertices and edges, but are nevertheless not isomorphic.

$\mathrm{CanonicalGraph}\left(\mathrm{SpecialGraphs}:-\mathrm{FosterCageGraph}\left(\right)\right)$

$\mathrm{CanonicalGraph}\left(\mathrm{SpecialGraphs}:-\mathrm{MeringerGraph}\left(\right)\right)$

$\mathrm{EqualEntries}\left( \mathrm{AdjacencyMatrix}\left(\right)\, \mathrm{AdjacencyMatrix}\left( \right)\right)$

The new command Eccentricity computes the eccentricity of the graph at a specified vertex or, if not specified, computes the list of eccentricities at each vertex. The eccentricity of a vertex $v$ is the maximum graph distance between $v$ and any other vertex in the graph.

$\mathrm{Eccentricity}\left( \mathrm{SpecialGraphs}:-\mathrm{HoffmanGraph}\left(\right) \right)$

The maximum eccentricity over the entire graph is known as the graph diameter and can be computed with GraphTheory[Diameter] (also available in previous Maple versions).$\mathrm{Diameter}\left( \mathrm{SpecialGraphs}:-\mathrm{HoffmanGraph}\left(\right)\right)$

The minimum eccentricity over the entire graph is known as the graph radius, and it can be computed directly using the new command Radius:

$\mathrm{Radius}\left( \mathrm{SpecialGraphs}:-\mathrm{HoffmanGraph}\left(\right)\right)$

The general-purpose commands Import and Export as well as the GraphTheory commands GraphTheory[ImportGraph], GraphTheory[ExportGraph], and GraphTheory[ConvertGraph] now support the Digraph6 graph format.  The Digraph6 format is a concise text-based format for serializing a directed graph.

For more information on supported graph-theoretic formats in Maple, see Formats.

The SpecialGraphs subpackage now includes built-in commands to generate the following special graphs: