|
#############################################################################
##
## This file is part of recog, a package for the GAP computer algebra system
## which provides a collection of methods for the constructive recognition
## of groups.
##
## This files's authors include Max Neunhöffer, Ákos Seress.
##
## Copyright of recog belongs to its developers whose names are too numerous
## to list here. Please refer to the COPYRIGHT file for details.
##
## SPDX-License-Identifier: GPL-3.0-or-later
##
##
## Some corrections to the library.
##
#############################################################################
# Here I collect some hacks that are necessary with the current GAP,
# they should be removed some day:
InstallOtherMethod( ExtractSubMatrix, "hack: for lists of compressed vectors",
[ IsList, IsList, IsList ],
function( m, poss1, poss2 )
local i,n;
n := [];
for i in poss1 do
Add(n,ShallowCopy(m[i]{poss2}));
od;
if IsFFE(m[1,1]) then
ConvertToMatrixRep(n);
fi;
return n;
end );
InstallMethod( PseudoRandom, "for a group object with generators, use func",
[ IsGroup and HasGeneratorsOfGroup ], 1,
function( g )
local l;
# FIXME: get rid of this hackish override of PseudoRandom,
# and define our own operation instead (say, RECOG_PseuoRandom)?!
# Or at least change pseudorandomfunc to an attribute, so that
# the filter of this method can be turned into something like
# IsGroup and HasPseudoRandomFunc
if IsBound(g!.pseudorandomfunc) and Length(g!.pseudorandomfunc) > 0 then
l := Length(g!.pseudorandomfunc);
return CallFuncList(g!.pseudorandomfunc[l].func,
g!.pseudorandomfunc[l].args);
fi;
TryNextMethod();
end );
# Randomize methods for non-compressed vectors, to support fields with more
# than 256 elements; needed by RECOG.RuleOutSmallProjOrder
InstallOtherMethod( Randomize, "for a mutable FFE vector",
[ IsFFECollection and IsPlistRep and IsMutable ],
v -> Randomize(GlobalMersenneTwister, v));
InstallOtherMethod( Randomize, "for a mutable FFE vector and a random source",
[ IsFFECollection and IsPlistRep and IsMutable, IsRandomSource ],
{ v, rs } -> Randomize(rs, v) );
InstallOtherMethod( Randomize, "for a random source and a mutable FFE vector",
[ IsRandomSource, IsFFECollection and IsPlistRep and IsMutable ],
function( rs, v )
local f,i;
f := DefaultField(v);
for i in [1..Length(v)] do v[i] := Random(rs,f); od;
return v;
end );
[ Dauer der Verarbeitung: 0.28 Sekunden
(vorverarbeitet)
]
|
