passagemath-lrslib

=============================================================================== passagemath: Reverse search for vertex enumeration and convex hulls with lrslib

passagemath <https://github.com/passagemath/passagemath>__ is open source mathematical software in Python, released under the GNU General Public Licence GPLv2+.

It is a fork of SageMath <https://www.sagemath.org/>__, which has been developed 2005-2025 under the motto “Creating a Viable Open Source Alternative to Magma, Maple, Mathematica, and MATLAB”.

The passagemath fork was created in October 2024 with the following goals:

• providing modularized installation with pip, thus completing a major project started in 2020 in the Sage codebase <https://github.com/sagemath/sage/issues/29705>__,
• establishing first-class membership in the scientific Python ecosystem,
• giving clear attribution of upstream projects <https://groups.google.com/g/sage-devel/c/6HO1HEtL1Fs/m/G002rPGpAAAJ>__,
• providing independently usable Python interfaces to upstream libraries,
• providing platform portability and integration testing services <https://github.com/passagemath/passagemath/issues/704>__ to upstream projects,
• inviting collaborations with upstream projects,
• building a professional, respectful, inclusive community <https://groups.google.com/g/sage-devel/c/xBzaINHWwUQ>__,
• developing a port to Pyodide <https://pyodide.org/en/stable/>__ for serverless deployment with Javascript,
• developing a native Windows port.

Full documentation <https://doc.sagemath.org/html/en/index.html>__ is available online.

passagemath attempts to support all major Linux distributions and recent versions of macOS. Use on Windows currently requires the use of Windows Subsystem for Linux or virtualization.

Complete sets of binary wheels are provided on PyPI for Python versions 3.9.x-3.12.x. Python 3.13.x is also supported, but some third-party packages are still missing wheels, so compilation from source is triggered for those.

About this pip-installable distribution package

This pip-installable distribution passagemath-lrslib provides an interface to lrslib <http://cgm.cs.mcgill.ca/~avis/C/lrs.html>_ by David Avis, an implementation of the reverse search algorithm for vertex enumeration and convex hull problems.

What is included

• Binary wheels on PyPI contain prebuilt copies of lrslib executables.

Examples

Using lrslib programs on the command line::

$ pipx run --pip-args="--prefer-binary" --spec "passagemath-lrslib" sage -sh -c lrs
*lrs:lrslib v.7.1 2021.6.2(64bit,lrslong.h,hybrid arithmetic)

Finding the installation location of an lrslib program::

$ pipx run --pip-args="--prefer-binary" --spec "passagemath-lrslib[test]" ipython

In [1]: from sage.features.lrs import LrsNash

In [2]: LrsNash().absolute_filename()
Out[2]: '/Users/mkoeppe/.local/pipx/.cache/db3f5a0e2996f81/lib/python3.11/site-packages/sage_wheels/bin/lrsnash'

Use with sage.game_theory <https://doc.sagemath.org/html/en/reference/game_theory/index.html>_::

$ pipx run --pip-args="--prefer-binary" --spec "passagemath-lrslib[test]" ipython

In [1]: from sage.all__sagemath_lrslib import *

In [2]: A = matrix([[1, -1], [-1, 1]]); B = matrix([[-1, 1], [1, -1]])

In [3]: matching_pennies = NormalFormGame([A, B])

In [4]: matching_pennies.obtain_nash(algorithm='lrs')
Out[4]: [[(1/2, 1/2), (1/2, 1/2)]]