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TSP needs more usage info

Open JoelPasvolsky opened this issue 6 years ago • 2 comments

Description Most TSP problems I try fail to produce a minimal route. The parameters and working range of solvable problems should be outlined.

To Reproduce The following alternative weights to the 5-node problem, EdgeView([(0, 1), (0, 2), (0, 3), (1, 2), (1, 3), (2, 3)]), all fail:

  • [{'weight': 22.36}, {'weight': 10.0}, {'weight': 14.14}, {'weight': 20.0}, {'weight': 22.36}, {'weight': 22.36}] produces route: [3, 1, 0] (non-Hamiltonian route)
  • [{'weight': 2.24}, {'weight': 1.0}, {'weight': 1.41}, {'weight': 2.0}, {'weight': 2.24}, {'weight': 2.24}] produces route: [1, 0, 3, 2] (a better answer is [1 2 0 3])
  • [{'weight': 2}, {'weight': 4}, {'weight': 1}, {'weight': 2}, {'weight': 4}, {'weight': 3}] produces route: [3, 2, 1, 0] (a better answer is [2 1 0 3])

Expected behavior More info on range of problem inputs, how to set lagrange, etc

Environment:

  • OS: Windows
  • Python version: 2.7

Additional context @vgoliber

JoelPasvolsky avatar Dec 13 '18 20:12 JoelPasvolsky

Choosing a value for a Lagrange parameter is a topic that is relevant for all of our algorithm tools (not just TSP). I think it would be more appropriate to provide higher level guidance and/or references on this subject as a whole rather than guidance specific to each algorithm.

vgoliber avatar Dec 13 '18 23:12 vgoliber

Agree, @vgoliber, you mentioned having references and some guidance. Please add that here for that general update. Thanks!

JoelPasvolsky avatar Dec 14 '18 00:12 JoelPasvolsky