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<!-- $Id: manual.xml,v 1.27 2008/01/28 16:00:28 alexk Exp $ -->

<!DOCTYPE Book SYSTEM "gapdoc.dtd"

[<!ENTITY Wedderga "<Package>Wedderga</Package>">] >

<Book Name="Wedderga">

<TitlePage>
  <Title>&Wedderga;</Title>
  <Subtitle>Wedderburn Decomposition of Group Algebras</Subtitle>
  <Version>Version 4.3.2</Version>

  <Author>Osnel Broche Cristo 
          <Email>osnel@ufla.br</Email>
          <Address>
          Departamento de Ciências Exatas,
          Universidade Federal de Lavras - UFLA,
          Campus Universitário - Caixa Postal 3037,
          37200-000, Lavras - MG, Brazil          
          </Address>
  </Author>

  <Author>Alexander Konovalov
          <Email>konovalov@member.ams.org</Email>
	      <Homepage>http://www.cs.st-andrews.ac.uk/&tilde;alexk/</Homepage>
          <Address>
          School of Computer Science, University of St Andrews<Br/>
          Jack Cole Building, North Haugh,<Br/>
          St Andrews, Fife, KY16 9SX, Scotland
          </Address> 
  </Author>

  <Author>Aurora Olivieri
          <Email>olivieri@usb.ve</Email>
          <Address>
          Departamento de Matemáticas<Br/>
	      Universidad Simón Bolívar<Br/>
          Apartado Postal 89000, Caracas 1080-A, Venezuela
          </Address> 
  </Author>
  
  <Author>Gabriela Olteanu
          <Email>golteanu@um.es, olteanu@math.ubbcluj.ro</Email>
          <Address>
          Department of Mathematics and Computer Science<Br/>
          North University of Baia Mare<Br/>
          Victoriei 76, 430122 Baia Mare, Romania
          </Address> 
  </Author>
  
  <Author>Ángel del Río
          <Email>adelrio@um.es</Email>
	      <Homepage>http://www.um.es/adelrio</Homepage>
          <Address>
          Departamento de Matemáticas, Universidad de Murcia<Br/>
          30100 Murcia, Spain
          </Address> 
  </Author>  
    
  <Date>January 2008</Date>

<Abstract>

<Index Key="Wedderga package">&Wedderga; package</Index> 
The title ``&Wedderga;'' stands for ``<B>WEDDER</B>burn decomposition of 
<B>G</B>roup <B>A</B>lgebras. This is a &GAP; package to compute the simple 
components of the Wedderburn decomposition of semisimple group algebras of finite 
groups over finite fields and over subfields of finite cyclotomic extensions of the rationals. 
It also contains functions that produce the primitive central idempotents 
of semisimple group algebras. 
Other functions of &Wedderga; allow to construct crossed products over
a group with coefficients in an associative ring with identity and the
multiplication determined by a given action and twisting.

</Abstract>

<Copyright>
  &copyright; 2006-2008 by Osnel Broche Cristo, Alexander Konovalov, Aurora
  Olivieri, Gabriela Olteanu and Ángel del Río.<P/>

  &Wedderga; is free software; you can redistribute it and/or modify it 
  under the terms of the GNU General Public License as published by 
  the Free Software Foundation; either version 2 of the License, or 
  (at your option) any later version. For details, see the FSF's own site
  <URL>http://www.gnu.org/licenses/gpl.html</URL>.<P/>

  If you obtained &Wedderga;, we would be grateful for a short notification
  sent to one of the authors.<P/>

  If you publish a result which was partially obtained with the usage of
  &Wedderga;, please cite it in the following form:<P/>

  O. Broche Cristo, A. Konovalov, A. Olivieri, G. Olteanu and Á. del Río. 
  <E>Wedderga --- Wedderburn Decomposition of Group Algebras, 
  Version 4.3.2;</E> 2008 (<URL>http://www.um.es/adelrio/wedderga.htm</URL>).
</Copyright>
  
<Acknowledgements>
We all are very grateful to Steve Linton for communicating the package and to
the referee for careful testing &Wedderga; and useful suggestions. Also we 
acknowledge very much the members of the &GAP; team: Thomas Breuer, 
Alexander Hulpke, Frank L&#252;beck and many other colleagues 
for helpful comments and advise. We would like also to thank Thomas Breuer 
for the code of <C>PrimitiveCentralIdempotentsByCharacterTable</C> for 
rational group algebras.
<P/> 

On various stages the development of the Wedderga package was supported by 
the following institutions:
<List>
  <Item>University of Murcia;</Item>
  <Item>Francqui Stichting grant ADSI107;</Item>
  <Item>M.E.C. of Romania (CEEX-ET 47/2006);</Item>
  <Item>D.G.I. of Spain;</Item>
  <Item>Fundación Séneca of Murcia;</Item>
  <Item>CAPES and FAPESP of Brazil.</Item>
</List>
We acknowledge with gratitude this support.<P/>

</Acknowledgements>

</TitlePage>

<TableOfContents/>

<Body>

<#Include SYSTEM "intro.xml">
<#Include SYSTEM "decomp.xml">
<#Include SYSTEM "SSP.xml">
<#Include SYSTEM "idempot.xml">
<#Include SYSTEM "crossed.xml"> 
<#Include SYSTEM "auxiliar.xml">
<#Include SYSTEM "theory.xml"> 

</Body>

<Bibliography Databases="manualbib.xml"/>

<TheIndex/>

</Book>