GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
#############################################################################
##
## Basic.gd MatricesForHomalg package Mohamed Barakat
##
## Copyright 2007-2008 Lehrstuhl B für Mathematik, RWTH Aachen
##
## Declarations of homalg basic procedures.
##
#############################################################################
####################################
#
# global functions and operations:
#
####################################
# basic operations:
DeclareOperation( "BasisOfRows",
[ IsHomalgMatrix ] );
DeclareOperation( "BasisOfRows",
[ IsHomalgMatrix, IsHomalgMatrix ] );
DeclareOperation( "BasisOfColumns",
[ IsHomalgMatrix ] );
DeclareOperation( "BasisOfColumns",
[ IsHomalgMatrix, IsHomalgMatrix ] );
## this implicitly declares [ IsHomalgMatrix, IsHomalgMatrix ]
DeclareOperation( "DecideZero",
[ IsRingElement, IsHomalgMatrix ] );
DeclareOperation( "DecideZero",
[ IsRingElement, IsHomalgRingRelations ] );
DeclareOperation( "DecideZero",
[ IsHomalgMatrix, IsList ] );
DeclareOperation( "DecideZero",
[ IsHomalgMatrix ] );
DeclareOperation( "SyzygiesOfRows",
[ IsHomalgMatrix ] );
DeclareOperation( "SyzygiesOfRows",
[ IsHomalgMatrix, IsHomalgMatrix ] );
DeclareOperation( "LazySyzygiesOfRows",
[ IsHomalgMatrix, IsHomalgMatrix ] );
DeclareOperation( "SyzygiesOfColumns",
[ IsHomalgMatrix ] );
DeclareOperation( "SyzygiesOfColumns",
[ IsHomalgMatrix, IsHomalgMatrix ] );
DeclareOperation( "LazySyzygiesOfColumns",
[ IsHomalgMatrix, IsHomalgMatrix ] );
DeclareOperation( "ReducedSyzygiesOfRows",
[ IsHomalgMatrix ] );
DeclareOperation( "ReducedSyzygiesOfRows",
[ IsHomalgMatrix, IsHomalgMatrix ] );
DeclareOperation( "ReducedSyzygiesOfColumns",
[ IsHomalgMatrix ] );
DeclareOperation( "ReducedSyzygiesOfColumns",
[ IsHomalgMatrix, IsHomalgMatrix ] );
DeclareOperation( "SyzygiesBasisOfRows",
[ IsHomalgMatrix ] );
DeclareOperation( "SyzygiesBasisOfColumns",
[ IsHomalgMatrix ] );
DeclareOperation( "SyzygiesBasisOfRows",
[ IsHomalgMatrix, IsHomalgMatrix ] );
DeclareOperation( "SyzygiesBasisOfColumns",
[ IsHomalgMatrix, IsHomalgMatrix ] );
DeclareOperation( "RightDivide",
[ IsHomalgMatrix, IsHomalgMatrix ] );
DeclareOperation( "LeftDivide",
[ IsHomalgMatrix, IsHomalgMatrix ] );
DeclareOperation( "RightDivide",
[ IsHomalgMatrix, IsHomalgMatrix, IsHomalgMatrix ] );
DeclareOperation( "LeftDivide",
[ IsHomalgMatrix, IsHomalgMatrix, IsHomalgMatrix ] );
DeclareOperation( "GenerateSameRowModule",
[ IsHomalgMatrix, IsHomalgMatrix ] );
DeclareOperation( "GenerateSameColumnModule",
[ IsHomalgMatrix, IsHomalgMatrix ] );
# global functions:
DeclareGlobalFunction( "BestBasis" );
DeclareGlobalFunction( "SimplerEquivalentMatrix" );