gr1py

gr1py is an enumerative (or concrete) reactive synthesis tool for the GR(1) fragment of LTL. It is pure Python.

Installation

Releases are available from the Python Package Index <https://pypi.org/>_ at https://pypi.org/project/gr1py/ To get it from there and check the version, try ::

pip install gr1py gr1py -V

pip <https://pip.pypa.io>_ should get dependencies for you if you do not have them. They are

• PLY (https://www.dabeaz.com/ply/)

If it is available, NetworkX (https://networkx.github.io/) will be used. However, it is not required. A simple built-in class for directed graphs will be used if NetworkX is not found.

If you want to hack on gr1py, clone the repository from https://github.com/slivingston/gr1py.git

Current CI server report <https://github.com/slivingston/gr1py/actions/workflows/main.yml>_:

.. image:: https://github.com/slivingston/gr1py/actions/workflows/main.yml/badge.svg :alt: build status from GitHub Actions

Examples

Besides the Python package, a script named gr1py is installed that provides access to several routines from the command-line. Consider the file named examples/arbiter3.spc that is included in the source release. To check that the specification defined by it can be realized, try ::

gr1py -r examples/arbiter3.spc

To synthesize a winning strategy and dump it in the Graphviz DOT format, try ::

gr1py -t dot examples/arbiter3.spc > arbiter3-fsm.dot dot -Tsvg -O arbiter3-fsm.dot

where the second command uses the program dot (part of Graphviz) to create an SVG file, likely named arbiter3-fsm.dot.svg; e.g., the file can be displayed using a Web browser or Inkscape.

A summary of command-line usage can be obtained by grpy -h.

Input formats

The default input format is that of gr1c (http://scottman.net/2012/gr1c).

Output formats

These are selected from the command-line using the -t switch. Each corresponds to a function in gr1py.output.

• json : gr1c JSON <https://tulip-control.github.io/gr1c/md_formats.html#gr1cjson>_
• dot : Graphviz dot <https://www.graphviz.org>_

Feedback and contributing

Bug reports, feature requests, and comments can be submitted via the project issue tracker <https://github.com/slivingston/gr1py/issues>_ or via email to the authors.

Code contributions are welcome. To avoid redundant effort, please check for an existing issue or other indication of prior or intended work before starting. When ready for review, send a pull request <https://github.com/slivingston/gr1py/pulls>_.

License

This is free software released under the terms of the BSD 3-Clause License <https://opensource.org/licenses/BSD-3-Clause>_. There is no warranty; not even for merchantability or fitness for a particular purpose. Consult LICENSE for copying conditions.