GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
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## Polyhedron.gd Convex package Sebastian Gutsche
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## Copyright 2011 Lehrstuhl B für Mathematik, RWTH Aachen
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## Polyhedrons for Convex.
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DeclareCategory( "IsPolyhedron",
IsConvexObject );
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## Structural Elements
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# DeclareAttribute( "ExternalObject",
# IsPolyhedron );
DeclareAttribute( "MainPolytope",
IsPolyhedron );
DeclareAttribute( "VerticesOfMainPolytope",
IsPolyhedron );
DeclareAttribute( "TailCone",
IsPolyhedron );
DeclareAttribute( "RayGeneratorsOfTailCone",
IsPolyhedron );
DeclareAttribute( "HomogeneousPointsOfPolyhedron",
IsPolyhedron );
DeclareAttribute( "LatticePointsGenerators",
IsPolyhedron );
DeclareAttribute( "BasisOfLinealitySpace",
IsPolyhedron );
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## Properties
##
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DeclareProperty( "IsNotEmpty",
IsPolyhedron );
DeclareProperty( "IsBounded",
IsPolyhedron );
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## Constructors
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DeclareOperation( "PolyhedronByInequalities",
[ IsList ] );
DeclareOperation( "Polyhedron",
[ IsPolytope, IsCone ] );
DeclareOperation( "Polyhedron",
[ IsList, IsCone ] );
DeclareOperation( "Polyhedron",
[ IsPolytope, IsList ] );
DeclareOperation( "Polyhedron",
[ IsList, IsList ] );
DeclareOperation( "PolyhedronWithHomogeneousCoordinates",
[ IsList ] );