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Yesterday, Thomas Breuer has already given a first answer to Steve

Linton's question

Is there a comprehensive list of changes from 3.1 to 3.2?

I would like to add to his list a few more remarks concerning changes

and extensions of functions described in the manual chapters "Groups",

"Table of Marks", "Finite Polycyclic Groups", and "Finitely Presented

Groups".

Chapter "Groups" ----------------

Facilities for computing and printing the subgroup lattice of a

given group have been added, and an explicit description of the

respective new functions

Lattice

PrintClassSubgroupLattice

SetPrintLevel

has been added to the manual setcion.

The description of the TableOfMarks function has been removed from

the setcion and moved to an own chapter.

Chapter "Table of Marks" ------------------------

The function TableOfMarks to compute Burnside's table of marks of a

finite group has been changed and extended by several new functions

for handling such tables. The new chapter "Table of Marks" describes

all these functions:

TableOfMarks

Marks

NrSubs

WeightsTom

MatTom

TomMat

DecomposedFixedPointVector

TestTom

DisplayTom

NormalizerTom

IntersectionsTom

IsCyclicTom

FusionCharTableTom

PermCharsTom

MoebiusTom

CyclicExtensionsTom

IdempotentsTom

ClassTypesTom

ClassNamesTom

TomCyclic

TomDihedral

TomFrobenius

Chapter "Finite Polycyclic Groups" ----------------------------------

Since the release of version 3.1 some functions have been renamed or

replaced by global functions:

pQuotient -> PQuotient, PrimeQuotient

pQpresentationSave -> Save

pQpresentationRestore -> PQp

pQpresentationPrint -> Print

pQInit -> InitPQp

pQWeight -> Weight

NextClass -> NextClassPQp

pAbelianQuotient -> FirstClassPQp

DefiningGenerators -> Factorization

They are now properly described in the GAP 3.2 manual release.

Chapter "Finitely presented group" ----------------------------------

This chapter has been extended by six sections which describe new

functions for handling group presentations. As GAP does never allow

to alter any presentation which is part of a group record, we have

introduced so called "presentation records" as a new type of GAP

objects which are permitted to be changed. The functions

PresentationFpGroup

FpGroupPresentation

TzPrintStatus

TzPrintGenerators

TzPrintRelators

TzPrintPresentation

TzPrint

TzPrintLengths

TzPrintPairs

TzPrintOptions

Save

AddGenerator

AddRelator

RemoveRelator

allow to create, administrate, print, or alter such pressentation

records. In particular, Tietze transformations can be applied to

them via the functions

SimplifiedFpGroup

SimplifyPresentation

TzGo

TzGoGo

TzEliminate

TzSearch

TzSearchEqual

TzFindCyclicJoins

TzSubstitute

TzSubstituteCyclicJoins

Moreover, we offer new functions

PresentationSubgroup

PresentationSubgroupMtc

PresentationSubgroupRrs

PresentationNormalClosure

PresentationNormalClosureRrs

DecodeTree

for computing a presentation of a subgroup of a finitely presented

group using the so called Modified Todd-Coxeter method or the

Reduced Reidemeister-Schreier algorithm.

I hope these remarks will be another help in figuring out at least

some features which are new in GAP 3.2 .

Volkmar Felsch

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