5 Graph Description Language (GDL) - Absint

4.1.4 Edge Classes - Expose/Hide Edges
The edges of a graph can be partitioned statically into edge classes by providing an integer for each
edge. Edges with the same integer form a class. These edge class numbers appear in the Select
Edge Classes dialog box. Instead of the numbers the GDL specification can provide names for
edge classes, e. g. if a syntax tree with type information is visualized the edge classes could be
“type edges” and “syntax tree edges”.
After selecting Expose/Hide Edges... in the Folding menu the Select Edge Classes dialog
box appears (see Figure 8). The box shows all the edge classes present.
Edges of enabled edge classes and their target nodes are drawn in the graph window. Edges of
disabled edge classes and all nodes accessible via these edges are not drawn and are not considered
in the layout calculation of the graph.
4.1.5 Subgraph
Figure 8: Edge Class Menu
A graph can be partitioned into nested subgraphs. Subgraphs can be defined only statically, i. e. in
the graph specification. In the GDL specification, subgraphs should be specified in such a manner
so that the user can identify subgraphs and summary nodes and thus make use of all the operations
that work on subgraphs.
Operations: Subgraphs can be
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