## Software available for download

###
Trains: a program for computing train tracks of
surface homeomorphisms

This program is an implementation of Bestvina and Handel's algorithm
for determining train tracks of surface homeomorphisms
(Topology **34** (1995), 109-140). The current version of the
program is for Windows only.

You can download
the executable
and
a help
file containing detailed instructions (which should be placed in
the same directory as the executable). There is also
a pdf
version of the documentation, which is not so conveniently indexed
as the windows help file, but may be better for some purposes.

###
Dynn: a program for working with Dynnikov coordinates

This program is designed for calculations involving the action of
braids on integral laminations and measured foliations on punctured
disks, using Dynnikov's coordinate system. It is available as a
Windows executable (to be run on the command line) only.

You can download
the executable,
and
a PDF
file which contains a very brief summary of Dynnikov's coordinates
together with instructions for running the program.

### Horseshoe Calculator

Here is a horseshoe
calculator which calculates a range of braid type invariants of
horseshoe periodic orbits.

### Prune

This program, which is used for investigating pruning fronts in
Smale's horseshoe, can be
obtained here.

### lg

A little C++ program for calculating the left greedy form of a
positive braid can be
found here.