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3-manifolds / SnapPy

SnapPy is a package for studying the topology and geometry of 3-manifolds, with a focus on hyperbolic structures. It is based on the SnapPea kernel written by Jeff Weeks.
https://snappy.computop.org/
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Improvements when using low_index to find covers #104

Closed NathanDunfield closed 1 year ago

NathanDunfield commented 1 year ago
  1. Completely changed heuristic for designating which relators are short.
  2. Major speed up when repeatedly calling Triangulation.cover by not repeatedly calling the kernel function fundamental_group.
  3. Dealt with corner cases when Triangulation.fundamental_group returns the trivial presentation.
  4. Now require version 1.2 of low_index and so removed Triangulation._covers_low_index_old.

The combination of 1 and 2 means that low_index beats the SnapPea kernel in essentially all regimes.