An Implementation of the Bestvina-Handel Algorithm for Surface Homeomorphisms

摘要

Bestvina and Handel have found an effective algorithm that determines whethera given homeomorphism of an orientable, possibly punctured surface ispseudo-Anosov. We present a software package in Java that realizes thisalgorithm for surfaces with one puncture. Moreover, the package allows the userto define homeomorphisms in terms of Dehn twists, and in the pseudo-Anosov caseit generates images of train tracks in the sense of Bestvina-Handel.