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Contraction of Timetable Networks with Realistic Transfers

  • Robert Geisberger
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6049)

Abstract

We contribute a fast routing algorithm for timetable networks with realistic transfer times. In this setting, our algorithm is the first one that successfully applies precomputation based on node contraction: gradually removing nodes from the graph and adding shortcuts to preserve shortest paths. This reduces query times to 0.5 ms with preprocessing times below 4 minutes on all tested instances, even on continental networks with 30 000 stations. We achieve this by an improved contraction algorithm and by using a station graph model. Every node in our graph has a one-to-one correspondence to a station and every edge has an assigned collection of connections. Also, our graph model does not require parallel edges.

Keywords

route planning public transit algorithm engineering 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Robert Geisberger
    • 1
  1. 1.Karlsruhe Institute of Technology (KIT)KarlsruheGermany

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