GML-Format for SNDlib
In SNDlib, all problems and solutions are available for download in
(Graph Modelling Language) format, a portable standardised format for graphs.
For viewing, editing and analysing graphs written in GML we recommend
the free Graph
The format of a problem-GML is quite simple. There are nodes and links.
DIRECTED/BIDIRECTED links have source/target arrows, UNDIRECTED
links do not.
The following rules apply to a solution-GML:
- The thickness of a link corresponds to the installed capacity.
- A link which is not contained in the solution topology is
illustrated as a grey-dashed line.
- The color of a link corresponds to its maximum usage (maximum flow /
capacity) in any operating state. The darker the color, the higher
the usage of the link. A black link indicates full use of the
capacity. A light red link is nearly not used in all operating
You can create a GML file out of an SNDlib instance either with
the provided Java classes (see our
or by using the small C program
createGML.c kindly provided by
© 2006 Zuse-Institute Berlin (ZIB)