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 GNU LGPL 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:

Peter Eades, Ian Fogg, David Kelly,
SPREMB: A System for Developing Graph Algorithms,
Congressus Numerantium,
Volume 66, December 1988.

Stephen Skiena,
Implementing Discrete Mathematics:
Combinatorics and Graph Theory in Mathematica,
Addison Wesley, 1990.
Source Code:

coxeter.grf,
a GRF file created by one test and read by another.
Last revised on 07 September 2022