GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
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##
## ExternalSystem.gd ConvexForHomalg package Sebastian Gutsche
##
## Copyright 2011-2012 Lehrstuhl B für Mathematik, RWTH Aachen
##
## Declares Methods for an external CAS
##
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####################################
##
## Cone Methods
##
####################################
DeclareOperation( "EXT_CREATE_CONE_BY_RAYS",
[ IsList ] );
DeclareOperation( "EXT_CREATE_CONE_BY_RAYS_UNSAVE",
[ IsList ] );
DeclareOperation( "EXT_CREATE_CONE_BY_INEQUALITIES",
[ IsList ] );
DeclareOperation( "EXT_CREATE_CONE_BY_EQUALITIES_AND_INEQUALITIES",
[ IsList, IsList ] );
DeclareOperation( "EXT_CREATE_DUAL_CONE_OF_CONE",
[ IsExternalObject ] );
DeclareOperation( "EXT_RAYS_IN_FACETS",
[ IsExternalObject ] );
####################################
##
## Fan Methods
##
####################################
DeclareOperation( "EXT_FAN_BY_CONES",
[ IsList ] );
DeclareOperation( "EXT_FAN_BY_RAYS_AND_CONES",
[ IsList, IsList ] );
DeclareOperation( "EXT_FAN_BY_RAYS_AND_CONES_UNSAVE",
[ IsList, IsList ] );
####################################
##
## Polytope Methods
##
####################################
DeclareOperation( "EXT_CREATE_POLYTOPE_BY_POINTS",
[ IsList ] );
DeclareOperation( "EXT_CREATE_POLYTOPE_BY_INEQUALITIES",
[ IsList ] );
####################################
##
## Property Functions
##
####################################
DeclareOperation( "EXT_IS_POINTED_CONE",
[ IsExternalObject ] );
DeclareOperation( "EXT_IS_SMOOTH_CONE",
[ IsExternalObject ] );
DeclareOperation( "EXT_IS_VERY_AMPLE_POLYTOPE",
[ IsExternalObject ] );
DeclareOperation( "EXT_IS_COMPLETE_FAN",
[ IsExternalObject ] );
DeclareOperation( "EXT_IS_POINTED_FAN",
[ IsExternalObject ] );
DeclareOperation( "EXT_IS_SMOOTH_FAN",
[ IsExternalObject ] );
DeclareOperation( "EXT_IS_SIMPLICIAL_CONE",
[ IsExternalObject ] );
DeclareOperation( "EXT_IS_SIMPLICIAL_POLYTOPE",
[ IsExternalObject ] );
DeclareOperation( "EXT_IS_SIMPLE_POLYTOPE",
[ IsExternalObject ] );
DeclareOperation( "EXT_IS_LATTICE_POLYTOPE",
[ IsExternalObject ] );
DeclareOperation( "EXT_IS_NOT_EMPTY_POLYTOPE",
[ IsExternalObject ] );
DeclareOperation( "EXT_IS_NORMAL_POLYTOPE",
[ IsExternalObject ] );
DeclareOperation( "EXT_IS_REGULAR_FAN",
[ IsExternalObject ] );
####################################
##
## Attribute Functions
##
####################################
DeclareOperation( "EXT_AMBIENT_DIM_OF_CONE",
[ IsExternalObject ] );
DeclareOperation( "EXT_DIM_OF_CONE",
[ IsExternalObject ] );
DeclareOperation( "EXT_LATTICE_POINTS_OF_POLYTOPE",
[ IsExternalObject ] );
DeclareOperation( "EXT_RAYS_OF_FAN",
[ IsExternalObject ] );
DeclareOperation( "EXT_RAYS_IN_MAXCONES_OF_FAN",
[ IsExternalObject ] );
DeclareOperation( "EXT_VERTICES_OF_POLYTOPE",
[ IsExternalObject ] );
DeclareOperation( "EXT_NORMALFAN_OF_POLYTOPE",
[ IsExternalObject ] );
DeclareOperation( "EXT_DIM_OF_FAN",
[ IsExternalObject ] );
DeclareOperation( "EXT_AMBIENT_DIM_OF_FAN",
[ IsExternalObject ] );
DeclareOperation( "EXT_IS_FULL_DIMENSIONAL_CONE",
[ IsExternalObject ] );
DeclareOperation( "EXT_IS_FULL_DIMENSIONAL_FAN",
[ IsExternalObject ] );
DeclareOperation( "EXT_DRAW",
[ IsExternalObject ] );
DeclareOperation( "EXT_DEFINING_INEQUALITIES_OF_CONE",
[ IsExternalObject ] );
DeclareOperation( "EXT_FACET_INEQUALITIES_OF_POLYTOPE",
[ IsExternalObject ] );
DeclareOperation( "EXT_VERTICES_IN_FACETS",
[ IsExternalObject ] );
DeclareOperation( "EXT_INT_LATTICE_POINTS",
[ IsExternalObject ] );
DeclareOperation( "EXT_IS_BOUNDED_POLYTOPE",
[ IsExternalObject ] );
DeclareOperation( "EXT_CREATE_POLYTOPE_BY_HOMOGENEOUS_POINTS",
[ IsList ] );
DeclareOperation( "EXT_HOMOGENEOUS_POINTS_OF_POLYTOPE",
[ IsExternalObject ] );
DeclareOperation( "EXT_TAIL_CONE_OF_POLYTOPE",
[ IsExternalObject ] );
DeclareOperation( "EXT_MINKOWSKI_SUM",
[ IsExternalObject, IsExternalObject ] );
DeclareOperation( "EXT_LINEAR_SUBSPACE",
[ IsExternalObject ] );
DeclareOperation( "EXT_EQUALITIES_OF_CONE",
[ IsExternalObject ] );
DeclareOperation( "EXT_STELLAR_SUBDIVISION",
[ IsExternalObject, IsExternalObject ] );
DeclareOperation( "EXT_INTERSECTION_OF_CONES",
[ IsExternalObject, IsExternalObject ] );
DeclareOperation( "EXT_INTERSECTION_OF_POLYTOPES",
[ IsExternalObject, IsExternalObject ] );
DeclareOperation( "EXT_EQUALITIES_OF_POLYTOPE",
[ IsExternalObject ] );
DeclareOperation( "EXT_LATTICE_POINTS_GENERATORS",
[ IsExternalObject ] );
DeclareOperation( "EXT_F_VECTOR",
[ IsExternalObject ] );
####################################
#
# Recover Methods
#
####################################
DeclareOperation( "EXT_GENERATING_RAYS_OF_CONE",
[ IsExternalObject ] );
DeclareOperation( "EXT_HILBERT_BASIS_OF_CONE",
[ IsExternalObject ] );