############################################################################# ## #W README.unitlib The UnitLib package Alexander Konovalov #W Elena Yakimenko ## #H $Id: README.unitlib,v 1.6 2007/03/14 01:32:13 alexk Exp $ ## ############################################################################# The UnitLib Package ------------------- Let KG be a group algebra of a finite p-group G over the field K of characteristic p, and let V(KG) be the normalized unit group of KG. The pc-presentation of the group V(KG) can be computed using the GAP package LAGUNA (http://www.cs.st-andrews.ac.uk/~alexk/laguna.htm), but for groups of orders 64 and bigger this computation will already take a lot of time. The UnitLib package is an extension of the LAGUNA package that is aimed on this problem. It contains the library of normalized unit groups of modular group algebras of finite p-groups over the field of p elements. This allows the user to retrieve the pre-computed group from the library instead of the long-time computation. The group created with UnitLib will have the same properties and attributes as the one computed with LAGUNA. The current version of UnitLib contains normalized unit groups V(KG) for all p-groups of order not greater than 243. Installation and system requirements: UnitLib is designed for GAP4.4 and no compatibility with previous releases of GAP4 is guaranteed. Libraries of normalized unit groups of groups of orders less than 243, except for the order 128, will be available in any operating system. The library for groups of order 128 was compressed using gzip program and, therefore, will be available only in UNIX-type systems (including UNIX- installation in Mac OS X and Cygwin installation in Windows). To work with the library for groups of order 243 you will also need the cURL program (http://curl.haxx.se) to retrieve the data from the UnitLib homepage, and the GAP package QaoS (http://www.gap-system.org/Packages/qaos.html) which provides the GAP function Curl to work with cURL. Because the UnitLib is an extension of the LAGUNA package, you must have the LAGUNA package installed. You can obtain it from the GAP homepage or from http://www.cs.st-andrews.ac.uk/~alexk/laguna.htm. To use the UnitLib online help it is necessary to install the GAP4 package GAPDoc by Frank Luebeck and Max Neunhoeffer, which is available from the GAP homepage or from http://www.math.rwth-aachen.de/~Frank.Luebeck/GAPDoc/. UnitLib is distributed in standard formats (zoo, tar.gz, tar.bz2, -win.zip) and can be obtained the GAP homepage or from its homepage http://www.cs.st-andrews.ac.uk/~alexk/unitlib.htm. To unpack the archive unitlib-2.1.zoo you need the program unzoo, which can be obtained from the GAP homepage http://www.gap-system.org/ (see section `Distribution'). To install UnitLib, copy this archive into the 'pkg' subdirectory of your GAP4.4 installation. Then the subdirectory 'unitlib' containing the package will be created in the 'pkg' directory after the following command: unzoo -x unitlib-2.1.zoo Now you can start GAP and load the UnitLib package using the command: gap> LoadPackage("unitlib"); Alexander Konovalov and Elena Yakimenko March 2007