Hi,<br><br>&nbsp;&nbsp;&nbsp; I try to write my graph to std::cout with boost::write_graphviz.<br>&nbsp;&nbsp;&nbsp; In the example boost/libs/graph/example/graphviz.cpp, <br>&nbsp;&nbsp;&nbsp; the graph used is a&nbsp; <br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; boost::adjacency_list&lt;vecS, vecS, directedS,
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; property&lt;vertex_name_t, std::string&gt;,<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; property&lt;edge_weight_t, double&gt; &gt;<br><br>&nbsp;&nbsp;&nbsp; and all work fine.<br><br><br>&nbsp;&nbsp;&nbsp; my graph is a 
<br><br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; boost::adjacency_list&lt;listS, listS, bidirectedS,<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; property&lt;my_vertex_t, my_vertex&gt;,<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; property&lt;my_edge_t, my_edge&gt;,<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; property&lt;my_graph_t, my_graph&gt; ,<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; listS &gt;<br>
<br>&nbsp;&nbsp;&nbsp; If a do &quot;write_graphviz(std::cout, g);&quot;<br>&nbsp;&nbsp;&nbsp; I have a very big error.&nbsp; (why BGL didn&#39;t use boost concept check ???)<br>&nbsp;&nbsp;&nbsp; I search in boost code and i found !!!<br>&nbsp;&nbsp;&nbsp; In the file boost/graph/graphviz.hpp line 257&nbsp;&nbsp;&nbsp; (boost 
1.34)<br>&nbsp;&nbsp;&nbsp; &quot;out &lt;&lt; get(vertex_id, *i);&quot;<br><br><br>&nbsp;&nbsp;&nbsp; so write_graphviz function get the vertex property with the tag of type vertex_id.<br><br>&nbsp;&nbsp;&nbsp; By default, the type vertex_id is the enum boost::vertex_index 
<br>&nbsp;&nbsp;&nbsp;&nbsp; which do reference to the type boost::vertex_index_t;<br><br>&nbsp;&nbsp; This property is <span onclick="dr4sdgryt(event)">intrinsically</span> in the type boost::adjacency_list&lt;vecS, vecS&gt;<br>&nbsp;&nbsp;&nbsp;&nbsp; because the vertex_descriptor is the index of the vertex. And so all work fine with
<br>&nbsp;&nbsp;&nbsp;&nbsp; the function write_graphviz<br><br>&nbsp;&nbsp; With the type boost::adjacency_list&lt;vecS, listS&gt;, this property is not available. TOOOOOO<br><br>&nbsp;&nbsp; In the complete signature function :<br>&nbsp;&nbsp; void write_graphviz(std::ostream &amp;, const VertexListGraph &amp; g
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; vertexPropertyWrite vpw,<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; EdgePropertyWriter epw,<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; GraphPropertyWriter gpw,<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; VertexID vertex_id);
<br><br><br>&nbsp;&nbsp;&nbsp; I can give the property_tag to used in the function.<br>&nbsp;&nbsp;&nbsp; But, <span onclick="dr4sdgryt(event)">In opposition to </span>other BGL algorithm which accept an external PropertyMap,  <br>&nbsp;&nbsp;&nbsp; this property must be in the graph. And I don&#39;t want to add a index property.
<br><br><br>&nbsp;&nbsp; Question :<br>&nbsp;&nbsp; &nbsp;&nbsp; How to use write_graphviz algorithm with boost::adjacency_list&lt;listS, listS&gt; ?<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Is there a magic boost property tag to use with a boost::adjacency_list&lt;listS, listS&gt;
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; like the boost::vertex_index_t tag and the boost::adjacency_list&lt;vecS, vecS&gt;<br><br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; is there another solution ??<br><br>Thank<br>David Callu<br><br><span onclick="dr4sdgryt(event)">&nbsp;&nbsp;&nbsp; </span><br>&nbsp;&nbsp; 
<br><br>