riptor of the graph, and whose value type can be written to a stream. The value should be a unique descriptor for each vertex, and will be used to name each node in the Graphviz file (it will be escaped properly for Graphviz output).<br>
<b>Default</b>: If no <code>dynamic_properties</code> object is provided, <tt>get(vertex_index, g)</tt>. Otherwise, a dynamic property map that accesses the property map in <code>dp</code> whose name is given by the <code>node_id</code> parameter.
</blockquote>
<H3>
Example