GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
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#W field.gd Alnuth - ALgebraic NUmber THeory Bettina Eick
#W Bjoern Assmann
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DeclareInfoClass( "InfoAlnuth" );
DeclareRepresentation( "IsBasisOfMatrixField",
IsBasis and IsAttributeStoringRep, [] );
DeclareOperation( "ExponentsOfUnits", [IsNumberField, IsCollection] );
DeclareOperation( "IsPrimitiveElementOfNumberField",
[ IsNumberField, IsObject ] );
DeclareOperation( "RelationLattice", [IsNumberField, IsCollection] );
DeclareProperty( "IsUnitGroup", IsGroup );
DeclareProperty( "IsUnitGroupIsomorphism", IsMapping);
DeclareProperty( "IsNumberFieldByMatrices", IsNumberField );
DeclareProperty( "IsMultGroupByFieldElemsIsomorphism", IsMapping);
DeclareAttribute( "IntegerDefiningPolynomial", IsNumberField );
DeclareAttribute( "IntegerPrimitiveElement", IsNumberField );
DeclareAttribute( "EquationOrderBasis", IsNumberField );
DeclareAttribute( "MaximalOrderBasis", IsNumberField );
DeclareAttribute( "UnitGroup", IsNumberField );
DeclareAttribute( "DefiningPolynomial", IsNumberFieldByMatrices );
DeclareAttribute( "FieldOfUnitGroup", IsGroup );
DeclareGlobalFunction( "FieldOfPolynomial" );
DeclareGlobalFunction( "FieldByMatricesNC" );
DeclareGlobalFunction( "FieldByMatrixBasisNC" );
DeclareGlobalFunction( "FieldByPolynomialNC" );
DeclareGlobalFunction( "FieldByMatrices" );
DeclareGlobalFunction( "FieldByMatrixBasis" );
DeclareGlobalFunction( "FieldByPolynomial" );
DeclareGlobalFunction( "IntersectionOfUnitSubgroups" );
DeclareGlobalFunction( "IntersectionOfTFUnitsByCosets" );
DeclareGlobalFunction( "NormCosetsOfNumberField" );
DeclareGlobalFunction( "IsUnitOfNumberField" );
DeclareGlobalFunction( "RelationLatticeOfTFUnits");
DeclareGlobalFunction( "RelationLatticeModUnits");
DeclareGlobalFunction( "RelationLatticeTF");
DeclareGlobalFunction( "RelationLatticeOfUnits");
DeclareGlobalFunction( "PcpPresentationMultGroupByFieldEl");
DeclareGlobalFunction( "PcpPresentationOfMultiplicativeSubgroup");