/usr/share/gap/lib/teachmod.g is in gap-libs 4r6p5-3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 | #############################################################################
##
#W teachmod.g GAP library Alexander Hulpke
##
##
#Y Copyright (C) 2008 The GAP Group
##
## This file contains rotines that enable simplified display and turn on
## some naive routines, which are primarily of interest in a teaching
## context. It is made part of the general system to ensure it will be
## always installed with GAP.
##
## FFE Display
InstallMethod(ViewObj,true,[IsFFE],100,
function(x)
local p,d;
if TEACHMODE<>true then
TryNextMethod();
fi;
d:=DegreeFFE(x);
p:=Characteristic(x);
if d=1 then
Print("ZmodnZObj(",Int(x),",",p,")");
else
Print("Z(",p^d,")^",LogFFE(x,Z(p^d)));
fi;
end);
InstallMethod(String,true,[IsFFE],100,
function(x)
local p,d;
if TEACHMODE<>true then
TryNextMethod();
fi;
d:=DegreeFFE(x);
p:=Characteristic(x);
if d=1 then
return Concatenation("ZmodnZObj(",String(Int(x)),",",String(p),")");
else
return Concatenation("Z(",String(p^d),")^",String(LogFFE(x,Z(p^d))));
fi;
end);
InstallMethod( ZmodnZObj, "for prime residues convert to GF(p)",
[ IsInt, IsPosInt ],100,
function( residue, n )
if TEACHMODE<>true then
TryNextMethod();
fi;
if not IsPrimeInt(n) then
return ZmodnZObj( ElementsFamily( FamilyObj( ZmodnZ( n ) )), residue );
else
return residue*Z(n)^0;
fi;
end );
## Cyclotomics display
## Careful, this can affect the rationals!
InstallMethod(ViewObj,true,[IsCyc],100,
function(x)
local a,p, d, e, b, i;
if IsRat(x) or TEACHMODE<>true or Conductor(x)=4 then
TryNextMethod();
fi;
a:=Quadratic(x,true);
if a=fail then
TryNextMethod();
fi;
Print(a.display);
end);
# basic constructors -- if teaching mode they will default to fp groups
#############################################################################
##
#F AbelianGroup( [<filt>, ]<ints> ) . . . . . . . . . . . . . abelian group
##
BindGlobal( "AbelianGroup", function ( arg )
if Length(arg) = 1 then
if ForAny(arg[1],x->x=0) or TEACHMODE=true then
return AbelianGroupCons( IsFpGroup, arg[1] );
else
return AbelianGroupCons( IsPcGroup, arg[1] );
fi;
elif IsOperation(arg[1]) then
if Length(arg) = 2 then
return AbelianGroupCons( arg[1], arg[2] );
elif Length(arg) = 3 then
return AbelianGroupCons( arg[1], arg[2], arg[3] );
fi;
fi;
Error( "usage: AbelianGroup( [<filter>, ]<ints> )" );
end );
#############################################################################
##
#F CyclicGroup( [<filt>, ]<n> ) . . . . . . . . . . . . . . . cyclic group
##
BindGlobal( "CyclicGroup", function ( arg )
if Length(arg) = 1 then
if arg[1]=infinity or TEACHMODE=true then
return CyclicGroupCons(IsFpGroup,arg[1]);
fi;
return CyclicGroupCons( IsPcGroup, arg[1] );
elif IsOperation(arg[1]) then
if Length(arg) = 2 then
return CyclicGroupCons( arg[1], arg[2] );
elif Length(arg) = 3 then
return CyclicGroupCons( arg[1], arg[2], arg[3] );
fi;
fi;
Error( "usage: CyclicGroup( [<filter>, ]<size> )" );
end );
#############################################################################
##
#F DihedralGroup( [<filt>, ]<n> ) . . . . . . . dihedral group of order <n>
##
BindGlobal( "DihedralGroup", function ( arg )
if Length(arg) = 1 then
if TEACHMODE=true then
return DihedralGroupCons( IsFpGroup, arg[1] );
else
return DihedralGroupCons( IsPcGroup, arg[1] );
fi;
elif IsOperation(arg[1]) then
if Length(arg) = 2 then
return DihedralGroupCons( arg[1], arg[2] );
elif Length(arg) = 3 then
return DihedralGroupCons( arg[1], arg[2], arg[3] );
fi;
fi;
Error( "usage: DihedralGroup( [<filter>, ]<size> )" );
end );
#############################################################################
##
#F ElementaryAbelianGroup( [<filt>, ]<n> ) . . . . elementary abelian group
##
BindGlobal( "ElementaryAbelianGroup", function ( arg )
if Length(arg) = 1 then
if TEACHMODE=true then
return ElementaryAbelianGroupCons( IsFpGroup, arg[1] );
else
return ElementaryAbelianGroupCons( IsPcGroup, arg[1] );
fi;
elif IsOperation(arg[1]) then
if Length(arg) = 2 then
return ElementaryAbelianGroupCons( arg[1], arg[2] );
elif Length(arg) = 3 then
return ElementaryAbelianGroupCons( arg[1], arg[2], arg[3] );
fi;
fi;
Error( "usage: ElementaryAbelianGroup( [<filter>, ]<size> )" );
end );
|