Skip to main content
Log in

On the graphical relaxation of the symmetric traveling salesman polytope

  • FULL LENGTH PAPER
  • Published:
Mathematical Programming Submit manuscript

Abstract

The Graphical Traveling Salesman Polyhedron (GTSP) has been proposed by Naddef and Rinaldi to be viewed as a relaxation of the Symmetric Traveling Salesman Polytope (STSP). It has also been employed by Applegate, Bixby, Chvátal, and Cook for solving the latter to optimality by the branch-and-cut method. There is a close natural connection between the two polyhedra. Until now, it was not known whether there are facets in TT-form of the GTSP polyhedron which are not facets of the STSP polytope as well. In this paper we give an affirmative answer to this question for n ≥ 9. We provide a general method for proving the existence of such facets, at the core of which lies the construction of a continuous curve on a polyhedron. This curve starts in a vertex, walks along edges, and ends in a vertex not adjacent to the starting vertex. Thus there must have been a third vertex on the way.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Alevras D. and Padberg M.W. (2001). Linear optimization and Extensions: Problems and Solutions. Springer, Berlin Heidelberg New York

    MATH  Google Scholar 

  2. Applegate, D., Bixby R., Chvátal, V., Cook W.: On the solution of the Traveling Salesman Problem. In: Doc. Math. J. DMV (Extra Volume ICM), pp. 645–656 (1998)

  3. Applegate D., Bixby R., Chvátal V. and Cook W. (2001). TSP cuts which do not conform to the template paradigm. In: Jünger, M. and Naddef, D. (eds) Computational Combinatorial Optimization, pp 261–303. Springer, Berlin Heidelberg New York

    Google Scholar 

  4. Applegate D., Bixby R., Chvátal V. and Cook W. (2003). Implementing the Dantzig-Fulkerson–Johnson algorithm for large Traveling Salesman Problems. Math. Program. Ser. B 97(1–2): 91–153

    MATH  Google Scholar 

  5. Boyd S.C. and Cunningham W.H. (1991). Small Travelling Salesman Polytopes. Math. Oper. Res 16(2): 259–271

    Article  MATH  MathSciNet  Google Scholar 

  6. Carr, R.: Separating over classes of TSP inequalities defined by 0-node lifting in polynomial time. In: Cunningham, W.H., McCormick, S.T., Queyranne M, (eds.), Proc. IPCO V, pp. 460–474, (1996)

  7. Carr R. (2004). Separation algorithms for classes of STSP inequalities arising from a new STSP relaxation. Math. Oper. Res, 29(1): 80–91

    Article  MATH  MathSciNet  Google Scholar 

  8. Christof T., Jünger M. and Reinelt G. (1991). A complete description of the Traveling Salesman Polytope on 8 nodes. OR Letters 10: 497–500

    Article  MATH  Google Scholar 

  9. Christof, T., Löbel, A.: PORTA — a polyhedron representation algorithm, (1998) http://www.iwr.uni-heidelberg.de/groups/comopt/software/PORTA

  10. Christof, T., Reinelt, G.: SmaPo — library of Small Polytopes. http://www.iwr.uni-heidelberg.de/groups/comopt/software/SMAPO/tsp

  11. Christof T. and Reinelt G. (2001). Decomposition and parallelization techniques for enumerating the facets of combinatorial polytopes. Int. J. Comput. Geom. Appl. 11: 423–437

    Article  MATH  MathSciNet  Google Scholar 

  12. Cornuéjols G., Fonlupt J. and Naddef D. (1985). The traveling salesman problem on a graph and some related integer polyhedra. Math. Program. 33: 1–27

    Article  MATH  Google Scholar 

  13. Dantzig G., Fulkerson R. and Johnson S. (1954). Solution of a large-scale traveling salesman problem. Oper. Res. 2: 393–410

    MathSciNet  Google Scholar 

  14. Fleischmann B. (1985). A cutting plane procedure for the travelling salesman problem on road networks. Eur. J. Oper. Res. 21: 307–317

    Article  MATH  MathSciNet  Google Scholar 

  15. Fonlupt J. and Naddef D. (1992). The traveling salesman problem in graphs with some excluded minors. Math. Program. 53(2): 147–172

    Article  MATH  MathSciNet  Google Scholar 

  16. Goemans MX. (1995). Worst-case comparison of valid inequalities for the TSP. Math. Program. 69(2): 335–349

    MathSciNet  Google Scholar 

  17. Goemans MX. and Bertsimas DJ. (1993). Survivable networks, linear programming relaxations and the parsimonious property. Math. Program. 60(2): 145–166

    Article  MathSciNet  Google Scholar 

  18. Grötschel M. and Padberg MW. (1979). On the symmetric travelling salesman problem I: inequalities. Math. Program. 16: 265–280

    Article  MATH  Google Scholar 

  19. Jünger M., Reinelt G. and Rinaldi G. (1995). The traveling salesman problem. In: Ball, M.O., Magnanti, T.L., Monma, C.L., and Nemhauser, G.L. (eds) Handbooks in Operations Research, Management Science, vol. 7, chap. 4, pp 225–330. Elsevier, Amsterdam

    Google Scholar 

  20. Maurras J.F. (1975). Some results on the convex hull of Hamiltonian cycles of symmetric complete graphs. In: Roy, B. (eds) Combinatorial Programming: Methods and Applications, pp 179–190. Reidel, Dordrecht

    Google Scholar 

  21. Naddef D. and Rinaldi G. (1991). The Symmetric Traveling Salesman Polytope and its graphical relaxation: Composition of valid inequalities. Math. Program. 51: 359–400

    Article  MATH  MathSciNet  Google Scholar 

  22. Naddef D. and Rinaldi G. (1993). The graphical relaxation: A new framework for the Symmetric Traveling Salesman Polytope. Math. Program. 58: 53–88

    Article  MATH  MathSciNet  Google Scholar 

  23. Queyranne M. and Wang Y. (1993). Hamiltonian path and Symmetric Travelling Salesman polytopes. Math. Program. 58(1): 89–110

    Article  MATH  MathSciNet  Google Scholar 

  24. Schrijver, A.: Theory of Linear and Integer Programming. Wiley New York (1986)

  25. Theis D.O. (2005). Polyhedra, algorithms for the general routing problem. PhD Thesis, University of Heidelberg, Germany

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Marcus Oswald.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Oswald, M., Reinelt, G. & Theis, D.O. On the graphical relaxation of the symmetric traveling salesman polytope. Math. Program. 110, 175–193 (2007). https://doi.org/10.1007/s10107-006-0060-x

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10107-006-0060-x

Keywords

Mathematics Subject Classification (2000)

Navigation