eng
Schloss Dagstuhl – Leibniz-Zentrum für Informatik
Open Access Series in Informatics
2190-6807
2010-09-01
74
87
10.4230/OASIcs.ATMOS.2010.74
article
Engineering Time-Dependent Many-to-Many Shortest Paths Computation
Geisberger, Robert
Sanders, Peter
Computing distance tables is important for many logistics problems like the vehicle routing problem (VRP).
While shortest distances from all source nodes in S to all target nodes in T are time-independent, travel times are not.
We present the first efficient algorithms to compute time-dependent travel time tables in large time-dependent road networks.
Our algorithms are based on time-dependent contraction hierarchies (TCH), currently the fastest time-dependent speed-up technique.
The computation of a table is inherently in Theta(|S|*|T|), and therefore inefficient for large tables.
We provide one particular algorithm using only Theta(|S|+|T|) time and space, being able to answer queries two orders of magnitude faster than the basic TCH implementation.
If small errors are acceptable, approximate versions of our algorithms are further orders of magnitude faster.
https://drops.dagstuhl.de/storage/01oasics/oasics-vol014-atmos2010/OASIcs.ATMOS.2010.74/OASIcs.ATMOS.2010.74.pdf
time-dependent
travel time table
algorithm engineering
vrp