|
# SPDX-License-Identifier: GPL-2.0-or-later
# Modules: A homalg based package for the Abelian category of finitely presented modules over computable rings
#
# Implementations
#
## Declaration stuff for sets of relations.
####################################
#
# representations:
#
####################################
# a new representation for the GAP-category IsSetsOfRelations:
DeclareRepresentation( "IsSetsOfRelationsRep",
IsSetsOfRelations,
[ "ListOfPositionsOfKnownSetsOfRelations" ] );
####################################
#
# families and types:
#
####################################
# a new family:
BindGlobal( "TheFamilyOfHomalgSetsOfRelations",
NewFamily( "TheFamilyOfHomalgSetsOfRelations" ) );
# a new type:
BindGlobal( "TheTypeHomalgSetsOfRelations",
NewType( TheFamilyOfHomalgSetsOfRelations,
IsSetsOfRelationsRep ) );
####################################
#
# methods for operations:
#
####################################
InstallMethod( PositionOfLastStoredSetOfRelations,
"for sets of relations",
[ IsSetsOfRelationsRep ],
function( rels )
return Length( rels!.ListOfPositionsOfKnownSetsOfRelations );
end );
####################################
#
# constructor functions and methods:
#
####################################
InstallGlobalFunction( CreateSetsOfRelationsForLeftModule,
function( arg )
local relations;
if Length( arg ) = 1 then
relations := rec( ListOfPositionsOfKnownSetsOfRelations := [ 1 ],
1 := arg[1] );
elif IsString( arg[1] ) and Length( arg[1] ) > 2 and LowercaseString( arg[1]{[1..3]} ) = "unk" then
relations := rec( ListOfPositionsOfKnownSetsOfRelations := [ 1 ],
1 := "unknown relations" );
else
relations := rec( ListOfPositionsOfKnownSetsOfRelations := [ 1 ],
1 := HomalgRelationsForLeftModule( arg[1], arg[2] ) );
fi;
## Objectify:
Objectify( TheTypeHomalgSetsOfRelations, relations );
return relations;
end );
InstallGlobalFunction( CreateSetsOfRelationsForRightModule,
function( arg )
local relations;
if Length( arg ) = 1 then
relations := rec( ListOfPositionsOfKnownSetsOfRelations := [ 1 ],
1 := arg[1] );
elif IsString( arg[1] ) and Length( arg[1] ) > 2 and LowercaseString( arg[1]{[1..3]} ) = "unk" then
relations := rec( ListOfPositionsOfKnownSetsOfRelations := [ 1 ],
1 := "unknown relations" );
else
relations := rec( ListOfPositionsOfKnownSetsOfRelations := [ 1 ],
1 := HomalgRelationsForRightModule( arg[1], arg[2] ) );
fi;
## Objectify:
Objectify( TheTypeHomalgSetsOfRelations, relations );
return relations;
end );
####################################
#
# View, Print, and Display methods:
#
####################################
InstallMethod( ViewObj,
"for sets of relations",
[ IsSetsOfRelationsRep ],
function( o )
local l;
l := Length( o!.ListOfPositionsOfKnownSetsOfRelations );
Print( "<A set containing " );
if l = 1 then
Print( "a single set " );
else
Print( l, " sets " );
fi;
Print( "of relations of a homalg module>" );
end );
[ Dauer der Verarbeitung: 0.29 Sekunden
(vorverarbeitet)
]
|
