Abstract
We introduce the study of Conditional symmetry breaking in constraint programming. This arises in a sub-problem of a constraint satisfaction problem, where the sub-problem satisfies some condition under which additional symetries hold. Conditional symmetry can cause redundancy in a systematic search for solutions. Breaking this symmetry is an important part of solving a constraint satisfaction problem effectively. We demonstrate experimentally that three methods, well-known for breaking unconditional symmetries, can be applied to conditional symmetries. These are: adding conditional symmetry-breaking constraints, reformulating the problem to remove the symmetry, and augmenting the search process to break the conditional symmetry dynamically through the use of a variant of Symmetry Breaking by Dominance Detection (SBDD).
We thank Alan Frisch and Chris Jefferson. Ian Gent is supported by a Royal Society of Edinburgh SEELLD/RSE Support Research Fellowship. Ian Miguel is supported by a UK Royal Academy of Engineering/EPSRC Research Fellowship. This material is based in part on works supported by the Science Foundation Ireland under Grant No. 00/PI.1/C075.
Preview
Unable to display preview. Download preview PDF.
Similar content being viewed by others
References
Choi, C., Lee, J.H.: On the pruning behavior of minimal combined models for CSPs. In: Proceedings of the Workshop on Reformulating Constraint Satisfaction Problems (2002)
Crawford, J., Ginsberg, M.L., Luks, E., Roy, A.: Symmetry-breaking Predicates for Search Problems. In: Proc. of the 5th KRR, pp. 148–159 (1996)
Fahle, T., Schamberger, S., Sellmann, M.: Symmetry breaking. In: Walsh, T. (ed.) CP 2001. LNCS, vol. 2239, pp. 93–107. Springer, Heidelberg (2001)
Frisch, A.M., Hnich, B., Kiziltan, Z., Miguel, I., Walsh, T.: Global Constraints for Lexicographic Orderings. In: Van Hentenryck, P. (ed.) CP 2002. LNCS, vol. 2470, pp. 93–108. Springer, Heidelberg (2002)
Frisch, A.M., Miguel, I., Walsh, T.: Symmetry and Implied Constraints in the Steel Mill Slab Design Problem. In: Proc. Formul 2001, pp. 8–15 (2001)
Gallian, J.A.: Graph Labeling. The Electronic Journal of Combinatorics, Dynamic Surveys (DS6) (2003), www.combinatorics.org/Surveys
Gent, I.P., Jefferson, C.A., Lynce, I., Miguel, I., Nightingale, P., Smith, B.M., Tarim, A.: Search in the Patience Game Black Hole CP Pod Research Report 10 (2005)
Gent, I.P., Harvey, W., Kelsey, T.W.: Groups and Constraints: Symmetry Breaking During Search. In: Van Hentenryck, P. (ed.) CP 2002. LNCS, vol. 2470, pp. 415–430. Springer, Heidelberg (2002)
Gent, I.P., Harvey, W., Kelsey, T.W., Linton, S.A.: Generic SBDD Using Computational Group Theory. In: Rossi, F. (ed.) CP 2003. LNCS, vol. 2833, pp. 333–347. Springer, Heidelberg (2003)
Gent, I.P., McDonald, I., Smith, B.M.: Conditional Symmetry in the All-Interval Series Problem. In: Proc. SymCon 2003 (2003)
Parlett, D.: The Penguin Book of Patience. Penguin (1980)
Puget, J.-F., Régin, J.-C.: Solving the all-interval problem, Available from http://www.csplib.org
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2005 Springer-Verlag Berlin Heidelberg
About this paper
Cite this paper
Gent, I.P., Kelsey, T., Linton, S.A., McDonald, I., Miguel, I., Smith, B.M. (2005). Conditional Symmetry Breaking. In: van Beek, P. (eds) Principles and Practice of Constraint Programming - CP 2005. CP 2005. Lecture Notes in Computer Science, vol 3709. Springer, Berlin, Heidelberg. https://doi.org/10.1007/11564751_21
Download citation
DOI: https://doi.org/10.1007/11564751_21
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-29238-8
Online ISBN: 978-3-540-32050-0
eBook Packages: Computer ScienceComputer Science (R0)