protected void buildNode(PMML pmml, Context shared_context, Element node,
Vertex vertex, DirectedGraph<Vertex, Edge> graph)
throws PatternException {
// build a list of parameters from which the predicate will be evaluated
Schema schema = pmml.getSchema();
String[] param_names = schema.getParamNames();
List<String> params = new ArrayList<String>();
for (int i = 0; i < param_names.length; i++)
params.add(param_names[i]);