Pathfinding Algorithms for Mutating Weight Graphs

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Pathfinding Algorithms for Mutating Weight Graphs

• Haitao Mao
• Computer Systems Lab 2007-2008

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The Pathfinding Problem

• Given a weighted graph, its weight mutation
  history, a start vertex, and a destination
  vertex, find the best vertex to move to next

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Sample Input

• 5 7 0 4 5 (vertices, edges, start vertex, end
  vertex, history length)?
• 0 1 2 (first vertex, second vertex, edge
  weight)?
• 2.2 (history at a timestep for this edge)?
• 4 more history points
• Data for the other 6 edges of the graph
• Random Input Generator written this quarter

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Algorithms

• Preliminaries
• First algorithm (core)?
• Second algorithm (randomized distance)?
• Third algorithm (randomized distance with more
  complicated but not necessarily better heuristic)?

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Some very crude results

• Used random input generator to get input
• Two sizes (13, 500)?
• Not very varied graph structure in input data set

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Data

• Dijkstra 5.75 46.34
• First alg 4.32 28.46
• Second 4.25 24.09
• Third 4.07 25.95

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Next quarter

• More testing!
• More refinement of algorithm if necessary
• Writing up stuff