Twister page:

Twister is a program for building triangulations of three-manifolds, from the viewpoint of the mapping class group. The program is now maintained by Mark Bell. The easiest way to run Twister is as a module inside of SnapPy. Please see CompuTop for material on SnapPy (maintained by Nathan Dunfield and Marc Culler) and other topological software.

For those interested, the source code for Twister is available from Bitbucket. Also available there are Python scripts, using Twister and SnapPy, for generating censuses of hyperbolic manifolds.

The material below is out of date -- in particular, you can find much improved versions of the genus two census and the genus one (with two punctures) census at Bitbucket. Other census data is also available there.


  • Here's the download file: twister.tar posted 13/06/2008 (Unix only).
  • To unpack it type "tar -xvf twister.tar" at the command line.
  • For further explanation please read the documentation file format_twister.
  • We have produced a pair of lists. The first contains (probably) all genus two bundles over the circle with monodromy of length ten or less. The second does the same for the pure mapping class group of the twice-holed torus. We used Twister, SnapPea, and the Python front end for Snappea.
  • Please send any questions or comments to me or Tracy Hall.
  • Lots of other low-dimensional software can be found at CompuTop, maintained by Nathan Dunfield.
    Homepage: To my homepage.
    Warwick: Up to the math department webpage.