SnapPy¶
What is SnapPy?¶

SnapPy is a program for studying the topology and geometry of 3-manifolds, with a focus on hyperbolic structures. It runs on Mac OS X, Linux, and Windows, and combines a link editor and 3D-graphics for Dirichlet domains and cusp neighborhoods with a powerful command-line interface based on the Python programming language. You can see it in action, learn how to install it, and watch the tutorial.
News¶
- Version 2.4 (May 2016): New features include:
- Added census of Platonic manifolds.
- Rigorous computation of cusp translations.
- Added decorations to triangulation isomorphism signatures for encoding peripheral curves.
- Faster verification of non-tetrahedral canonical cell decompositions.
- Improvements to the link and planar diagram component, mostly contributed by Malik Obeidin, include:
- Bar-Natan’s super-fast tangle-based algorithm for computing the Alexander polynomial.
- Can now compute the Seifert matrix and express a link as a braid closure.
- Conversion to/from SageMath links and braids.
- Many under-the-hood improvements.
- New Windows installer.
- Complete version history.
Documention¶
Credits¶
Written by Marc Culler, Nathan Dunfield, and Matthias Goerner using the SnapPea kernel written by Jeff Weeks, with contributions from many others. If you use SnapPy in your work, please cite it as described here.
Released under the terms of the GNU General Public License, version 2 or later.
The development of SnapPy was partially supported by grants from the National Science Foundation, including, DMS-0707136, DMS-0906155, DMS-1105476, and DMS-1510204. Any opinions, findings, and conclusions or recommendations expressed on this site are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.