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Join the Game Theory Discord <https://github.com/drvinceknight/equilibriumexplorers> server to chat -- direct invite link <https://discord.gg/NfTAkhAeyc>_.

Axelrod =======

Goals

---

A Python library with the following principles and goals:

• Enabling the reproduction of previous Iterated Prisoner's Dilemma research

as easily as possible.

• Creating the de-facto tool for future Iterated Prisoner's Dilemma

research.

• Providing as simple a means as possible for anyone to define and contribute

new and original Iterated Prisoner's Dilemma strategies.

• Emphasizing readability along with an open and welcoming community that

is accommodating for developers and researchers of a variety of skill levels.

Features

---

With Axelrod you:

• have access to over 200 strategies

<https://axelrod.readthedocs.io/en/stable/reference/strategyindex.html>, including original and classics like Tit For Tat and Win Stay Lose Shift. These are extendable through parametrization and a collection of strategy transformers.

• can create head to head matches

<https://axelrod.readthedocs.io/en/stable/tutorials/newtogametheoryandorpython/match.html>_ between pairs of strategies.

• can create tournaments

<https://axelrod.readthedocs.io/en/stable/tutorials/newtogametheoryandorpython/tournament.html>_ over a number of strategies.

• can study population dynamics through Moran processes

<https://axelrod.readthedocs.io/en/stable/tutorials/newtogametheoryandorpython/moran.html>_ and an infinite population model <https://axelrod.readthedocs.io/en/stable/how-to/runaxelrodsecologicalvariant.html>.

• can analyse detailed results of tournaments

<https://axelrod.readthedocs.io/en/stable/tutorials/newtogametheoryandorpython/summarisingtournaments.html> and matches.

• can visualise results

<https://axelrod.readthedocs.io/en/stable/tutorials/newtogametheoryandorpython/visualisingresults.html> of tournaments.

.. image:: http://axelrod.readthedocs.io/en/stable/images/demostrategies_boxplot.svg :height: 300 px :align: center

• can reproduce a number of contemporary research topics such as fingerprinting <https://axelrod.readthedocs.io/en/stable/how-to/fingerprint.html>_ of

strategies and morality metrics <https://axelrod.readthedocs.io/en/stable/how-to/calculatemoralitymetrics.html>_.

.. image:: https://github.com/Axelrod-Python/Axelrod-fingerprint/raw/master/assets/Tricky_Defector.png :height: 300 px :align: center

The library has 100% test coverage and is extensively documented. See the documentation for details and examples of all the features: http://axelrod.readthedocs.org/

An open reproducible framework for the study of the iterated prisoner's dilemma <http://openresearchsoftware.metajnl.com/article/10.5334/jors.125/>_: a peer reviewed paper introducing the library (22 authors).

Installation

---

The library is tested on Python versions 3.8, 3.9, and 3.10.

The simplest way to install is::

$ pip install axelrod

To install from source::

$ git clone https://github.com/Axelrod-Python/Axelrod.git $ cd Axelrod $ python setup.py install

Quick Start

---

The following runs a basic tournament::

>>> import axelrod as axl >>> players = [s() for s in axl.demo_strategies] # Create players >>> tournament = axl.Tournament(players, seed=1) # Create a tournament >>> results = tournament.play() # Play the tournament >>> results.ranked_names ['Defector', 'Grudger', 'Tit For Tat', 'Cooperator', 'Random: 0.5']

Examples

---

• https://github.com/Axelrod-Python/tournament is a tournament pitting all the

strategies in the repository against each other.

• https://github.com/Axelrod-Python/Axelrod-notebooks contains a set of example

Jupyter notebooks.

• https://github.com/Axelrod-Python/Axelrod-fingerprint contains fingerprints

(data and plots) of all strategies in the library.

Contributing

---

All artisanal contributions are welcome!

Code Generation Policy:

We do not accept any content that has been created with the assistance of generative code tools.

You can find helpful instructions about contributing in the documentation: https://axelrod.readthedocs.io/en/stable/how-to/contributing/index.html

Publications

---

You can find a list of publications that make use of or cite the library on the citations <https://github.com/Axelrod-Python/Axelrod/blob/master/citations.md>_ page.

Contributors

---

The library has had many awesome contributions from many great contributors <https://github.com/Axelrod-Python/Axelrod/graphs/contributors>_. The Core developers of the project are:

• drvinceknight <https://github.com/drvinceknight>_
• gaffney2010 <https://github.com/gaffney2010>_
• marcharper <https://github.com/marcharper>_
• meatballs <https://github.com/meatballs>_
• nikoleta-v3 <https://github.com/Nikoleta-v3>_

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