Predicate dependency graph (was using gxref on a single module)

> 
> Next, there is the pack graphml, which writes GraphML files.  Then
> you have tools like Gephi to draw wonderful graphs :-)  If you go that
> way, please send the picture :-)

Nearly there :)

I do this:
------------------------------
write_call_graph_to(Mod,Output) :-
   get_call_graph(Mod,Graph),
   graphml_write_ugraph(Output, nomap, [], Graph).

nomap(id,node(N),A) :- term_to_atom(N,A), writeln(nomap(id,node(N),A)).
-------------------------------
where get_call_graph/2 collects all the edges into a ugraph.
The XML looks sensible, but I don't know GraphML.
Gephi doesn't like it. It says "Invalid GML parsing (SEVERE)".

It does this even with a very simple example that produces this output:
--------------------------------------
<?xml version="1.0" encoding="UTF-8"?>

<graphml
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://graphml.graphdrawing.org/xmlns"
    xsi:schemaLocation="http://graphml.graphdrawing.org/xmlns/1.0/graphml.xsd">
  <graph id="G" edgedefault="directed">
    <node id="1"/>
    <node id="2"/>
    <node id="3"/>
    <node id="4"/>
    <node id="5"/>
    <edge id="e0" source="1" target="3"/>
    <edge id="e1" source="1" target="5"/>
    <edge id="e2" source="2" target="4"/>
    <edge id="e3" source="4" target="5"/>
  </graph>
</graphml>
---------------------------------------
Is it a bug in the graph writing or in Gephi?

Samer.

> 
> 	Cheers --- Jan
> 
> [1] http://www.swi-prolog.org/pldoc/doc/swi/library/prolog_codewalk.pl
>