Pajek NET

Pajek NET files (extension .net) are plain text files representing network topology. This format focuses on the graph structure (nodes and edges); attribute support is limited — typically only labels are reliably imported by Gephi.

Nodes

Nodes are declared after the *Vertices N line where N is the number of nodes. Each node line contains a numeric identifier and an optional quoted label.

*Vertices 82670
1 "entity"
2 "thing"
3 "anything"
4 "something"
5 "nothing"
6 "whole"

When nodes have no labels, the importer relies on the vertices count and generates numbered identifiers:

*Vertices 2536

Edges

Edges can be described either as a list of node pairs (with the *arcs or *edges marker) or as adjacency lists (*edgeslist).

Pair list example (*arcs):

*arcs
4244 107
4244 238
4244 4292
4247 107
4248 1
4248 54

Edge weights can be added as a third column:

*arcs
4244 107 5

Adjacency list example (*edgeslist):

*edgeslist
4941 386 395 451
1 3553 3586 3587 3637
2 3583
3 4930
4 88
5 13 120

Additional information

• Lines starting with % are treated as comments.
• Pajek files may contain extra visual attributes (e.g. x_fact, y_fact, ic) but Gephi typically only imports the label.

Sample

*Vertices 9
*Edges
1 2
1 9
2 9
2 3
2 8
3 8
3 4
4 5
4 7
5 7
5 6
6 4