GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
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##
## Relative.gd Graded Modules package
##
## Copyright 2008-2010, Mohamed Barakat, University of Kaiserslautern
## Markus Lange-Hegermann, RWTH Aachen
##
## Declarations of procedures for the relative situation.
##
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#
# global functions and operations:
#
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# basic operations:
DeclareOperation( "RelativeRepresentationMapOfKoszulId",
[ IsHomalgModule, IsHomalgRing ] );
DeclareOperation( "RelativeRepresentationMapOfKoszulId",
[ IsHomalgModule ] );
DeclareOperation( "DegreeZeroSubcomplex",
[ IsHomalgComplex, IsHomalgRing ] );
DeclareOperation( "DegreeZeroSubcomplex",
[ IsHomalgComplex ] );