Notice: patsy is no longer under active development. As of August 2021, Matthew Wardrop (@matthewwardrop) and Tomás Capretto (@tomicapretto) have taken on responsibility from Nathaniel Smith (@njsmith) for keeping the lights on, but no new feature development is planned. The spiritual successor of this project is Formulaic, and we recommend those interested in new feature development contribute there. Those whose use-cases continue to be met by patsy can continue using this package with increased confidence that things will continue to work as is for the foreseeable future.

Patsy is a Python library for describing statistical models (especially linear models, or models that have a linear component) and building design matrices. Patsy brings the convenience of R "formulas" to Python.

• Documentation: https://patsy.readthedocs.io/
• Downloads: http://pypi.python.org/pypi/patsy/
• Code and issues: https://github.com/pydata/patsy
• Mailing list: [email protected] (http://groups.google.com/group/pydata)

• Python (2.6, 2.7, or 3.3+)
• six
• numpy
• Optional:
  • pytest/pytest-cov: needed to run tests
  • scipy: needed for spline-related functions like bs

pip install patsy (or, for traditionalists: python setup.py install)

2-clause BSD, see LICENSE.txt for details.