Now showing items 1-4 of 4

    • Automatically improving constraint models in Savile Row 

      Nightingale, Peter; Akgün, Özgür; Gent, Ian P.; Jefferson, Christopher; Miguel, Ian; Spracklen, Patrick (2017-10) - Journal article
      When solving a combinatorial problem using Constraint Programming (CP) or Satisfiability (SAT), modelling and formulation are vital and difficult tasks. Even an expert human may explore many alternatives in modelling a ...
    • Automatically improving constraint models in Savile Row through associative-commutative common subexpression elimination 

      Nightingale, Peter; Akgun, Ozgur; Gent, Ian P.; Jefferson, Christopher; Miguel, Ian (Springer, 2014-09-08) - Conference item
      When solving a problem using constraint programming, constraint modelling is widely acknowledged as an important and difficult task. Even a constraint modelling expert may explore many models and spend considerable time ...
    • Minimal and canonical images 

      Jefferson, Christopher; Jonauskyte, Eliza; Pfeiffer, Markus; Waldecker, Rebecca (2019-03-01) - Journal article
      We describe a family of new algorithms for finding the canonical image of a set of points under the action of a permutation group. This family of algorithms makes use of the orbit structure of the group, and a chain of ...
    • New refiners for permutation group search 

      Jefferson, Christopher; Pfeiffer, Markus; Waldecker, Rebecca (2019-05) - Journal article
      Partition backtrack is the current generic state of the art algorithm to search for subgroups of a given permutation group. We describe an improvement of partition backtrack for set stabilizers and intersections of subgroups ...