By default the DrawGraph command draws the edges and vertices of the graph with the same set of style options. The command StyleVertex, allows you to specify individual styles for specified vertices overriding the default or a previously set style.

Given only a graph G and a vertex or vertices V, StyleVertex marks the specified vertices to be rendered with the default highlight style.

The simplest way to customize the rendering is to give C, a color for the vertex. The colors C can be given in any form understood by Maple. See ColorTools/Formats for details. When the color of the vertex is set the color of the vertex label is set automatically to an appropriately contrasting grayscale.

If V is a list or Array of vertices then a list of colors or stylesheets is used to associate a different color or style to each member.

By default, this command modifies G and returns nothing. If you supply the option inplace = false, then instead the changes are applied to a copy of G, and that copy is returned.

More precise control of the style can be set using stylesheet options. The stylesheet options are understood as modifiers to the default highlight style. So, for example, if a color is not specified the default highlight color is used. If the stylesheet option and a color C are both given, the color C is ignored.

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

$\mathrm{K5}≔\mathrm{CompleteGraph}\left(5\right)$

$\mathrm{K5}≔\mathrm{Graph\; 1:\; an\; undirected\; graph\; with\; 5\; vertices\; and\; 10\; edge(s)}$

$\mathrm{StyleVertex}\left(\mathrm{K5}\,1\,\mathrm{color}=''Red''\right)$

$\mathrm{DrawGraph}\left(\mathrm{K5}\right)$

$\mathrm{StyleVertex}\left(\mathrm{K5}\,\left\{1\,3\right\}\,\mathrm{color}=''DodgerBlue''\right)$

$\mathrm{DrawGraph}\left(\mathrm{K5}\right)$

$\mathrm{StyleVertex}\left(\mathrm{K5}\,\left\{1\,3\right\}\,\mathrm{font}=\left[''Courier''\,''bold''\,14\right]\,\mathrm{thickness}=3\right)$

$\mathrm{DrawGraph}\left(\mathrm{K5}\right)$

$G≔\mathrm{Graph}\left(\left\{\left\{1\,2\right\}\,\left\{1\,3\right\}\,\left\{2\,3\right\}\,\left\{3\,4\right\}\,\left\{4\,5\right\}\,\left\{4\,6\right\}\,\left\{5\,6\right\}\right\}\right)$

$G≔\mathrm{Graph\; 2:\; an\; undirected\; graph\; with\; 6\; vertices\; and\; 7\; edge(s)}$

$A≔\mathrm{ArticulationPoints}\left(G\right)$

$A≔\left[3\,4\right]$

$H≔\mathrm{StyleVertex}\left(G\,A\,\mathrm{color}=''Magenta''\,\mathrm{border}=\mathrm{false}\,\mathrm{fontstyle}=''bold''\,\mathrm{inplace}=\mathrm{false}\right)$

$H≔\mathrm{Graph\; 3:\; an\; undirected\; graph\; with\; 6\; vertices\; and\; 7\; edge(s)}$

$\mathrm{DrawGraph}\left(H\right)$

$\mathrm{DrawGraph}\left(G\right)$

$\mathrm{StyleVertex}\left(G\,\left[1\,5\right]\,\left[\mathrm{color}=''Fill\; Spring\; Blue''\right]\,\left[\mathrm{color}=''Fill\; Spring\; Yellow''\right]\right)$

$\mathrm{DrawGraph}\left(G\right)$

$\mathrm{StyleVertex}\left(G\,\left[2\,3\right]\,\left[\left[\mathrm{fontstyle}=''italic''\right]\,\left[\mathrm{fontstyle}=''bold''\right]\right]\right)$

$\mathrm{DrawGraph}\left(G\right)$

The GraphTheory[StyleVertex] command was introduced in Maple 2020.

For more information on Maple 2020 changes, see Updates in Maple 2020.