**Pyperplan** is a lightweight STRIPS planner written in Python.

Please note that Pyperplan deliberately prefers clean code over fast
code. It is designed to be used as a teaching or prototyping tool. If
you use it for paper experiments, please state clearly that Pyperplan
does not offer state-of-the-art performance.

It was developed during the planning practical course at
Albert-Ludwigs-Universität Freiburg during the winter term 2010/2011 and
is published under the terms of the GNU General Public License 3
(GPLv3).

Pyperplan supports the following PDDL fragment: STRIPS without action
costs. This file only gives the basic information to get you up and
running. The full documentation can be found in the doc directory. You
can either read the text file documentation.txt directly or run "make"
in the doc directory to convert it to a PDF document.

# Requirements

Pyperplan requires Python >= 3.6. If Python 3 is not installed on your
system, install it with your package manager or download it from
<https://python.org>. For example,

    sudo apt install python3

will install Python 3 on an Ubuntu system.

# Installation

In addition to running the planner directly from a repository clone, you
can install Pyperplan from the Python package index (PyPI):

    pip install pyperplan

This makes the `pyperplan` script available globally or in your [virtual
environment](https://docs.python.org/3/tutorial/venv.html) (recommended).

# Usage

The planner is invoked through the file src/pyperplan.py and accepts two
arguments: a PDDL domain file and a PDDL problem file. Example:

    ./src/pyperplan.py benchmarks/tpp/domain.pddl benchmarks/tpp/task01.pddl

The domain file can be omitted, in which case the planner will attempt
to guess its name based on the problem file. If a plan is found, it is
stored alongside the problem file with a .soln extension.

By default, the planner performs a blind breadth-first search, which
does not scale very well. Heuristic search algorithms are available. For
example, to use greedy-best-first search with the FF heuristic, run

    ./src/pyperplan.py -H hff -s gbf DOMAIN PROBLEM

For a list of available search algorithms and heuristics, run

    ./src/pyperplan.py --help

For more information on using the planner and how to extend it to do
more fancy stuff, see doc/documentation.md.

# FAQs

## PDDL types

Pyperplan follows the semantics that all types other than the universal
supertype object (which is mentioned as such in the PDDL 1.2 paper) need
to be explicitly introduced.

# Contact

Pyperplan is hosted on GitHub: <https://github.com/aibasel/pyperplan>

The original authors of Pyperplan are, in alphabetical order:

  - Yusra Alkhazraji
  - Matthias Frorath
  - Markus Grützner
  - Thomas Liebetraut
  - Manuela Ortlieb
  - Jendrik Seipp
  - Tobias Springenberg
  - Philip Stahl
  - Jan Wülfing

The instructors of the course in which Pyperplan was created were Malte
Helmert and Robert Mattmüller.

If you want to get in touch with us, please contact Robert Mattmüller or
Jendrik Seipp. Their email addresses can easily be found on the web.

# Citing Pyperplan

Please cite Pyperplan using

    @Misc{alkhazraji-et-al-zenodo2020,
      author =       "Yusra Alkhazraji and Matthias Frorath and Markus Gr{\"u}tzner
                      and Malte Helmert and Thomas Liebetraut and Robert Mattm{\"u}ller
                      and Manuela Ortlieb and Jendrik Seipp and Tobias Springenberg and
                      Philip Stahl and Jan W{\"u}lfing",
      title =        "Pyperplan",
      publisher =    "Zenodo",
      year =         "2020",
      doi =          "10.5281/zenodo.3700819",
      url =          "https://doi.org/10.5281/zenodo.3700819",
      howpublished = "\url{https://doi.org/10.5281/zenodo.3700819}"
    }
