  
  [1X2 [33X[0;0Y[5XUnitLib[105X[101X[1X functions[133X[101X
  
  [33X[0;0YSince  the main purpose of [5XUnitLib[105X is the date storage, it has only two main
  user  functions  to  read  the  description of [22XV(KG)[122X for the given catalogue
  number  of  [22XG[122X in the Small Groups Library of the [5XGAP[105X system, and to save the
  description  of  [22XV(KG)[122X  if  the  user would like to store it for the further
  usage for the group which is not contained in the library.[133X
  
  [33X[0;0YTo use the [5XUnitLib[105X package first you need to load it as follows:[133X
  
  [4X[32X  Example  [32X[104X
    [4X[28X[128X[104X
    [4X[25Xgap>[125X [27XLoadPackage("unitlib");[127X[104X
    [4X[28X----------------------------------------------------------------------------[128X[104X
    [4X[28XLoading  UnitLib 3.1.0 (The library of normalized unit groups of modular group algebras)[128X[104X
    [4X[28Xby Alexander Konovalov (http://www.cs.st-andrews.ac.uk/~alexk/) and[128X[104X
    [4X[28X   Elena Yakimenko.[128X[104X
    [4X[28XHomepage: http://www.cs.st-andrews.ac.uk/~alexk/unitlib/[128X[104X
    [4X[28X----------------------------------------------------------------------------[128X[104X
    [4X[28Xtrue[128X[104X
    [4X[28X[128X[104X
  [4X[32X[104X
  
  [33X[0;0YUnder  Windows,  a  warning  will be displayed about non-availability of the
  library of normalized unit groups for groups of orders 128.[133X
  
  [33X[0;0YExamples  below  contain  some functions from the [5XLAGUNA[105X package [BKRS], see
  their description in the [5XLAGUNA[105X manual ([14XLAGUNA: LAGUNA package[114X).[133X
  
  
  [1X2.1 [33X[0;0YMainFunctions[133X[101X
  
  [1X2.1-1 PcNormalizedUnitGroupSmallGroup[101X
  
  [29X[2XPcNormalizedUnitGroupSmallGroup[102X( [3Xs[103X, [3Xn[103X ) [32X function
  [6XReturns:[106X  [33X[0;10YPcGroup[133X
  
  [33X[0;0YLet [3Xs[103X be a power of prime [22Xp[122X and [3Xn[103X is an integer from [10X[ 1 .. NrSmallGroups(s)
  ][110X.  Then  [10XPcNormalizedUnitGroupSmallGroup([3Xs[103X[10X,[3Xn[103X[10X)[110X  returns  the normalized unit
  group [22XV(KG)[122X of the modular group algebra [22XKG[122X, where [22XG[122X is [10XSmallGroup([3Xs[103X[10X,[3Xn[103X[10X)[110X (see
  [2XSmallGroup[102X  ([14XReference:  SmallGroup  for  group order and index[114X)) and [22XK[122X is a
  field of [22Xp[122X elements.[133X
  
  [4X[32X  Example  [32X[104X
    [4X[28X[128X[104X
    [4X[25Xgap>[125X [27XPcNormalizedUnitGroupSmallGroup(128,161);[127X[104X
    [4X[28X<pc group of size 170141183460469231731687303715884105728 with 127 generators>[128X[104X
    [4X[28X[128X[104X
  [4X[32X[104X
  
  [33X[0;0YThe  result returned by [10XPcNormalizedUnitGroupSmallGroup[110X is equivalent to the
  following:[133X
  
  [4X[32X  Example  [32X[104X
    [4X[28X                                                                         [128X[104X
    [4X[25Xgap>[125X [27XG := SmallGroup( s, n );[127X[104X
    [4X[25Xgap>[125X [27Xp := PrimePGroup( G );[127X[104X
    [4X[25Xgap>[125X [27XK := GF( p );[127X[104X
    [4X[25Xgap>[125X [27XKG := GroupRing( K, G );[127X[104X
    [4X[25Xgap>[125X [27XPcNormalizedUnitGroup( KG );[127X[104X
    [4X[28X                                                                               [128X[104X
  [4X[32X[104X
  
  [33X[0;0YNevertheless,  [10XPcNormalizedUnitGroupSmallGroup[110X  is  not  just a shortcut for
  such computation. It reads the description of the normalized unit group from
  the  [5XUnitLib[105X  library and then reconstructs all its necessary attributes and
  properties.  Thus,  if  you would like to obtain the group algebra [22XKG[122X or the
  field [22XK[122X and the group [22XG[122X, you should extract them from [22XV(KG)[122X, which should be
  constructed first.[133X
  
  [4X[32X  Example  [32X[104X
    [4X[28X[128X[104X
    [4X[25Xgap>[125X [27XV:=PcNormalizedUnitGroup(GroupRing(GF(2),SmallGroup(8,3)));[127X[104X
    [4X[28X<pc group of size 128 with 7 generators>[128X[104X
    [4X[25Xgap>[125X [27XV1:=PcNormalizedUnitGroupSmallGroup(8,3);                   [127X[104X
    [4X[28X<pc group of size 128 with 7 generators>[128X[104X
    [4X[25Xgap>[125X [27XV1=V;     # two isomorphic groups but not identical objects[127X[104X
    [4X[28Xfalse[128X[104X
    [4X[25Xgap>[125X [27XIdGroup(V)=IdGroup(V1);[127X[104X
    [4X[28Xtrue[128X[104X
    [4X[25Xgap>[125X [27XIsomorphismGroups(V,V1);[127X[104X
    [4X[28X[ f1, f2, f3, f4, f5, f6, f7 ] -> [ f1, f2, f3, f4, f5, f6, f7 ][128X[104X
    [4X[25Xgap>[125X [27XKG:=UnderlyingGroupRing(V1);  # now the correct way[127X[104X
    [4X[28X<algebra-with-one over GF(2), with 3 generators>[128X[104X
    [4X[25Xgap>[125X [27XV1=PcNormalizedUnitGroup(KG); # V1 is an attribute of KG[127X[104X
    [4X[28Xtrue[128X[104X
    [4X[25Xgap>[125X [27XK:=UnderlyingField(KG);[127X[104X
    [4X[28XGF(2)[128X[104X
    [4X[25Xgap>[125X [27XG:=UnderlyingGroup(KG);     [127X[104X
    [4X[28X<pc group of size 8 with 3 generators>[128X[104X
    [4X[28X[128X[104X
  [4X[32X[104X
  
  [33X[0;0YMoreover,  the  original  group  [22XG[122X  can  be  embedded into the output of the
  [10XPcNormalizedUnitGroupSmallGroup[110X, as it is shown in the next example:[133X
  
  [4X[32X  Example  [32X[104X
    [4X[28X[128X[104X
    [4X[25Xgap>[125X [27Xf:=Embedding(G,V1); [127X[104X
    [4X[28X[ f1, f2, f3 ] -> [ f2, f1, f3 ][128X[104X
    [4X[25Xgap>[125X [27Xg:=List(GeneratorsOfGroup(G), x -> x^f ); [127X[104X
    [4X[28X[ f2, f1, f3 ][128X[104X
    [4X[25Xgap>[125X [27XG1:=Subgroup(V1,g);[127X[104X
    [4X[28XGroup([ f2, f1, f3 ])[128X[104X
    [4X[25Xgap>[125X [27XIdGroup(G1);[127X[104X
    [4X[28X[ 8, 3 ][128X[104X
    [4X[28X[128X[104X
  [4X[32X[104X
  
  [33X[0;0YIf  the  first argument [3Xs[103X (the order of a group) is not a power of prime, an
  error  message  will appear. If [3Xs[103X is bigger than 243, you will get a warning
  telling that the library does not contain [22XV(KG)[122X for [22XG[122X of such order, and you
  can use only data that you already stored in your [11Xunitlib/userdata[111X directory
  with the help of the function [2XSavePcNormalizedUnitGroup[102X ([14X2.1-2[114X).[133X
  
  [33X[0;0YIt  is  worth to mention that for some groups of order 243, the construction
  of  the  normalized  unit  group  using  [10XPcNormalizedUnitGroupSmallGroup[110X may
  already  require  some noticeable amount of time. For example, it took about
  166  seconds  of CPU time to compute [10XPcNormalizedUnitGroupSmallGroup(243,30)[110X
  on Intel Xeon 3.4 GHz with 2048 KB cache.[133X
  
  [1X2.1-2 SavePcNormalizedUnitGroup[101X
  
  [29X[2XSavePcNormalizedUnitGroup[102X( [3XG[103X ) [32X function
  [29X[2XParSavePcNormalizedUnitGroup[102X( [3XG[103X ) [32X function
  [6XReturns:[106X  [33X[0;10Ytrue[133X
  
  [33X[0;0YLet  [3XG[103X  be  a finite [22Xp[122X-group of order [22Xs[122X from the Small Groups Library of the
  [5XGAP[105X  system,  constructed  with  the help of [10XSmallGroup(s,n)[110X (see [2XSmallGroup[102X
  ([14XReference:    SmallGroup    for    group    order    and    index[114X)).   Then
  [10XSavePcNormalizedUnitGroup([3XG[103X[10X)[110X  creates  the  file  with  the name of the form
  [11Xus_n.g[111X  in the directory [11Xunitlib/userdata[111X, and returns [9Xtrue[109X if this file was
  successfully generated. This file contains the description of the normalized
  unit  group  [22XV(KG)[122X  of  the group algebra of the group [3XG[103X over the field of [22Xp[122X
  elements.[133X
  
  [33X[0;0YIf  the  order  of  [3XG[103X  is greater than 243, after this you can construct the
  group  [22XV(KG)[122X  using [2XPcNormalizedUnitGroupSmallGroup[102X ([14X2.1-1[114X) similarly to the
  previous  section.  The  preliminary warning will be displayed, telling that
  for  such orders you can use only those groups that were already computed by
  the  user  and  saved to the [11Xunitlib/userdata[111X directory. If there will be no
  such  file  there,  you will get an error message, otherwise the computation
  will begin.[133X
  
  [33X[0;0YIf  the order of [3XG[103X is less or equal to 243, then the file will be created in
  the  [11Xunitlib/userdata[111X  directory,  but [5XUnitLib[105X will continue to use the file
  with  the  same name from the appropriate directory in [11Xunitlib/data[111X. You can
  compare these two files to make it sure that they are the same.[133X
  
  [33X[0;0Y[12XNOTE THAT:[112X[133X
  
  [33X[0;0Y1. The argument should be the underlying group [22XG[122X and not the normalized unit
  group [22XV(KG)[122X.[133X
  
  [33X[0;0Y2.  The  argument  should  be  a  group  from  the  [5XGAP[105X Small Groups Library
  constructed with the help of [10XSmallGroup(s,n)[110X, otherwise the date consistency
  may be lost.[133X
  
  [33X[0;0Y[2XParSavePcNormalizedUnitGroup[102X  works  in  the same way, but uses the function
  [10XParPcNormalizedUnitGroup[110X  to  parallelise  the  computation  using  the  [5XGAP[105X
  package [5XSCSCP[105X.[133X
  
  [4X[32X  Example  [32X[104X
    [4X[28X[128X[104X
    [4X[25Xgap>[125X [27XSavePcNormalizedUnitGroup( SmallGroup( 256, 56092 ) );[127X[104X
    [4X[28Xtrue[128X[104X
    [4X[25Xgap>[125X [27XPcNormalizedUnitGroupSmallGroup( 256, 56092 );[127X[104X
    [4X[28XWARNING : the library of V(KG) for groups of order [128X[104X
    [4X[28X256 is not available yet !!! [128X[104X
    [4X[28XYou can use only groups from the unitlib/userdata directory [128X[104X
    [4X[28Xin case if you already computed their descriptions [128X[104X
    [4X[28X(See the manual for SavePcNormalizedUnitGroup).[128X[104X
    [4X[28X#I  Description of V(KG) for G=SmallGroup(256,[128X[104X
    [4X[28X56092) accepted, started its generation...[128X[104X
    [4X[28X<pc group of size [128X[104X
    [4X[28X57896044618658097711785492504343953926634992332820282019728792003956564819968[128X[104X
    [4X[28X  with 255 generators>[128X[104X
    [4X[28X[128X[104X
  [4X[32X[104X
  
