ApplicationsFinite group actionsOrbit-enumeration in SYMMETRICAOrbit-construction in SYMMETRICA

Orbit-construction in SYMMETRICA

Now let me describe some procedures for computing complete lists (so called transversals) of standard representatives for a given group action. For doing this it is convenient to replace an arbitrary group action GX on an n-set by a similar action of a permutation group H£Sn on the set {1,...,n} . Then the smallest element of an orbit w is considered to be the standard representative of w.

The idea for these routines is the following. Input a permutation group and a set, where this group is acting on. The program then computes a list of all orbit representatives. Such algorithms were used to determine all graphs on k points [11][10], all different resonance structures of the fullerene C60 [7] or all k-motives in music theory [4][3].

At first it is described how to input permutation groups, then the various group actions are discussed.

  • Generators of permutation groups
  • Generators of induced actions
  • Special routines for wreath products
  • Some further generators
  • Actions of the form GX
  • Action on the domain of functions

  • harald.fripertinger@kfunigraz.ac.at,
    last changed: November 19, 2001

    ApplicationsFinite group actionsOrbit-enumeration in SYMMETRICAOrbit-construction in SYMMETRICA