Node patterns, combined with path patterns, define a connected pattern graph. The pattern graph may additionally:

• Combine several path patterns without node pattern.
• Use unconnected part with the separator comma (,).
• Include boolean valued expression as condition.

If several path pattern are used between two node pattern, it is implicitly using any type of node. E.g. Node > > +> Node finds nodes connected with a path of two successor edges, and one branch edge.

Unconnected pattern are defined with a comma. E.g. n1:Node, n2:Node find all pairs of nodes, without imposing any relation between the two. The two nodes will be separately matched, i.e. n1 != n2.

Additional conditions can be used as boolean-valued expression. These expression must be declared between parentheses (( and )). E.g. n:Sphere, (n.diameter == 5) .