grf_io

grf_io, a Python code which reads or writes a GRF file containing information about an abstract graph.

The file includes information about

• adjacency, that is, which nodes are connected to a given node;
• embedding, that is, how to place each node in the unit square so that a drawing of the graph is visually pleasing and "readable".

Licensing:

The computer code and data files described and made available on this web page are distributed under the MIT license

Languages:

grf_io is available in a C++ version and a FORTRAN90 version and a MATLAB version and a Python version.

Related Data and Programs:

graffiti, a dataset directory which contains 195 abstract graphs, with adjacency and embedding information, stored in the GRF format.

grf, a data directory which contains a description of the GRF format and some examples.

Reference:

1. Peter Eades, Ian Fogg, David Kelly,
   SPREMB: A System for Developing Graph Algorithms,
   Congressus Numerantium,
   Volume 66, December 1988.
2. Stephen Skiena,
   Implementing Discrete Mathematics: Combinatorics and Graph Theory in Mathematica,
   Addison Wesley, 1990.

Source Code:

• grf_io.py, the source code.
• grf_io.sh, runs all the tests.
• grf_io.txt, the output file.
• coxeter.grf, a GRF file created by one test and read by another.

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Last revised on 07 September 2022