The ε-Approximation of the Time-Dependent Shortest Path Problem Solution for All Departure Times

František Kolovský, Jan Ježek, Ivana Kolingerová
2019 ISPRS International Journal of Geo-Information  
In this paper, the shortest paths search for all departure times (profile search) are discussed. This problem is called a time-dependent shortest path problem (TDSP) and is suitable for time-dependent travel-time analysis. Particularly, this paper deals with the ε -approximation of profile search computation. The proposed algorithms are based on a label correcting modification of Dijkstra's algorithm (LCA). The main idea of the algorithm is to simplify the arrival function after every
more » ... step so that the maximum relative error is maintained. When the maximum relative error is 0.001, the proposed solution saves more than 97% of breakpoints and 80% of time compared to the exact version of LCA. Furthermore, the runtime can be improved by other 15% to 40% using heuristic splitting of the original departure time interval to several subintervals. The algorithms we developed can be used as a precomputation step in other routing algorithms or for some travel time analysis.
doi:10.3390/ijgi8120538 fatcat:q2ayzyu7jnfzvbbk6iwbhsrwhm