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Department of Mathematics
The City College of New York
NAC 8/133
Convent Ave at 138th Street
New York, NY 10031

Phone: (212) 650-5346
Fax: (212) 650-6294

CCNY :: Division of Science :: Mathematics

Department of Mathematics


XTrain is a Java 1.5 implementation of the Bestvina-Handel algorithm for homeomorphisms of surfaces with one puncture. Moreover, XTrain also computes triangulations of mapping tori of surface homeomorphisms, suitable for Jeff Weeks's program SnapPea. Surface homeomorphisms can be entered as a composition of Dehn twists with respect to a great variety of curves, or in terms of the induced automorphism of the fundamental group. XTrain was covered in depth here and here.

XTrain is written in Java and should run on all major operating systems. Just download the file xtrain.jar (attached below) and double-click on it to launch XTrain. XTrain is covered by the GNU General Public License. Please don't hesitate to contact me if you have any questions.

Advanced features

Click here for information on some advanced features of XTrain.

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