Improved physarum polycephalum shortest path algorithm with preconditioned iterative methods

Keskiner, Hamide Hande
Algorithms for finding the shortest path has many applications in Computer Science, or in other areas of science and engineering. Network optimizations, artificial intelligence and robotics are just a few examples where efficient computation of the shortest path is needed. Various algorithms have been proposed to solve this fundamental problem. Physarum Solver is biologically inspired method that deals with this problem. In the end, a sparse linear system needs to be solved at each iteration of the algorithm. Direct and iterative solvers are two main classes of algorithms for solving sparse linear systems. Direct solvers are robust but they could consume a lot memory due to fill-in. In this thesis, Physarum Polycephalum Shortest Path algorithm is improved using preconditioned iterative methods. We study the convergence behavior as well as memory consumption of various solvers and preconditioners. We show that preconditioned iterative solvers are quite robust and requires much less memory and solution time.


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Citation Formats
H. H. Keskiner, “Improved physarum polycephalum shortest path algorithm with preconditioned iterative methods,” M.S. - Master of Science, Middle East Technical University, 2015.