Differences between revisions 1 and 2
Revision 1 as of 2007-06-15 00:33:15
Size: 1614
Editor: DavidJoyner
Comment:
Revision 2 as of 2008-11-14 13:41:50
Size: 1614
Editor: anonymous
Comment: converted to 1.6 markup
Deletions are marked like this. Additions are marked like this.
Line 3: Line 3:
 AUTHORS: David Joyner, David Roe[[BR]]  AUTHORS: David Joyner, David Roe<<BR>>

G-module SEP

  • AUTHORS: David Joyner, David Roe

OBJECTIVE

Create

  • 1. a Python class data structure representing a finite rank G-module R, where G is a given group (already defined in SAGE),
  • 2. a Python class representing a group-with-action G on a set X, where X is a given set (or list?).

PROPERTIES

  • 1. The G-module class should be able to:
    • interface with the MeatAxe data types (see section 3.1.2 of the MeatAxe manual),

    • structure inherited by FreeModule class,

    • have default construction of ZZ[G] but allow for constructing F[H], where F is any field and H is a group containing G,
    • implements a G-set X by simply constructing the free abelian group ZZ[X] = ZZ^X,
    • interface with the HAP free ZZ[G]-module data type (Here is some info from HAP's manual: "In order to represent a word w in a free ZG-module M of rank n we use a list of integer pairs w=[ [i1,t1], [i2,t2], ..., [ik,tk] ]. The integers ij lie in the range between -n and n and correspond to the free ZZ[G]-generators of M and their additive inverses. The integers tj are positive and correspond to the group element eltsG[tj]. The (partial) listing eltsG may contain duplicate copies of elements of G.")
    • interface with HAP's FpGModule(A,G) construction when G is a p-group and M = GF(p)[G]
  • 2. The group-with-action class should be able to:
    • implement group actions of a Galois group acting on a field,
    • if R is an instance of the G-module class then G is a group-with-action on R.