Trivial Graph Format
Trivial Graph Format (TGF) is a simple text-based adjacency list file format for describing graphs,{{r|rt15}} widely used because of its simplicity.{{r|pitas}}
Format
The format consists of a list of node definitions, which map node IDs to labels, followed by a list of edges, which specify node pairs and an optional edge label. Because of its lack of standardization, the format has many variations.{{r|rt15}} For instance, some implementations of the format require the node IDs to be integers,{{r|kde}} while others allow more general alphanumeric identifiers.
Each node definition is a single line of text starting with the node ID, separated by a space from its label.
The node definitions are separated from the edge definitions by a line containing the "#" character.
Each edge definition is another line of text, starting with the two IDs for the endpoints of the edge separated by a space. If the edge has a label, it appears on the same line after the endpoint IDs.{{r|kde}}
The graph may be interpreted as a directed or undirected graph. For directed graphs, to specify the concept of bi-directionality in an edge, one may either specify two edges (forward and back) or differentiate the edge by means of a label.
Example
A simple graph with two nodes and one edge might look like:
1 First node
2 Second node
1 2 Edge between the two
See also
- yEd, a graph editor that can handle TGF file format.
References
{{reflist|refs=
| last1 = Canabrava | first1 = Tomaz
| last2 = Cord-Landwehr | first2 = Andreas
| contribution = Chapter 4. Import and Export
| contribution-url = https://docs.kde.org/trunk5/en/kdeedu/rocs/import-export.html
| date = April 10, 2016
| title = The Rocs Handbook, Revision Rocs 2.1.50 (Applications 16.04)}}
| last = Pitas | first = Ioannis
| contribution = 1.5 Graph storage formats and visualization
| contribution-url = https://books.google.com/books?id=BvYYCwAAQBAJ&pg=PA14
| isbn = 9781498719056
| page = 14
| publisher = CRC Press
| series = Chapman & Hall/CRC Data Mining and Knowledge Discovery Series
| title = Graph-Based Social Media Analysis
| volume = 39
| year = 2016}}
| last1 = Roughan | first1 = Matthew
| last2 = Tuke | first2 = Jonathan
| contribution = The Hitchhikers Guide to Sharing Graph Data
| contribution-url = http://www.maths.adelaide.edu.au/matthew.roughan/Papers/hitch_hikers_guide.pdf
| date = August 2015
| doi = 10.1109/ficloud.2015.76
| publisher = IEEE
| title = 2015 3rd International Conference on Future Internet of Things and Cloud| s2cid = 14560300
}}
}}
External links
- [http://docs.yworks.com/yfiles/doc/developers-guide/tgf.html Using TGF in the yFiles Graph Drawing library]
- [http://reference.wolfram.com/mathematica/ref/format/TGF.html Using TGF in Wolfram Mathematica]
{{Graph representations}}