Download Instructions

On a Linux machine with GAP installed, the HAP library can be loaded as follows:

Changes Log

Version 1.4 was released on 03/05/2006.

Version 1.5 was released on 12/06/2006. GAP types were introduced for resolutions, chain complexes etc. and methods for PrintObj and ViewObj were introduced.  The functions Homology and Cohomology where changed to GAP operations. A Linux shell script "compile" for creating a GAC compiled version of the HAP functions was added. The performance of the functions NonabelianTensorSquare() and ResolutionPrimePowerGroup() was improved. Functions  ResolutionSubnormalSeries(), ResolutionAlmostCrystalGroup() and ResolutionAlmostCrystalQuotient() were added.

Version 1.6 was released on 15/08/2006. The functions Honology(), Cohomology() and PrimePartDerivedFunctor() have been speeded up.  Graphviz is now used to visualize Coxeter diagrams, Graphs of groups and Cayley graphs. The functions ResolutionGraphOfGroups(), ChevalleyEilenbergComplex(), LieAlgebraHomology, LowerCentralSeriesLieAlgebra(), ModPCohomologyRing(), ModPRingGenerators have been included.

Version 1.7 was released on 01/09/2006. The functions Epicentre() and IsGraphOfGroups() were renamed EpiCentre() and GraphofGroupsTest() due to name clashes arising from recent modifications to GAP.  A minor modification was made to the functions NonabelianTensorSquare() and ThirdHomotopyGroupOfSuspensionB() so that they run on nilpotent infinite groups when the NQ package is loaded.

Version 1.7.1 was released on 27/11/2006. The function HomologyPB() was added. This relies on the Simplicial Homology GAP package. It uses probabilistic methods to compute homology.

Version 1.7.3 was released on 7/03/2007. The efficiency of the code for the function ResolutionPrimePowerGroup() was improved. Also, a bug in the function  ThirdHomotopyGroupSuspensionB() was fixed.

Version 1.7.4 was released on 10/04/2007. A bug was fixed in the function NonabelianTensorProduct(). The bug caused incorrect answers. Also, the function PoincareSeries() was added.

Version 1.8 was released on 16/08/2007. A bug in the function ModPCohomologyRing() was fixed. The efficiency of the function Prank() was improved. The efficiency of the function ModPRingGenerators was improved. A contracting homotopy was added to the output of the function ResolutionPrimePowerGroup(). Quite a few additions were made to the list of functions for FpG-modules.  The function RandomHomomorphismOfFpGModules() still gives an incorrect output! The function GroupCohomology() was added. The output of GroupHomology(G,n,p) was changed from an integer to a list (in keeping with the output from GroupHomology(G,n) ). The manual/web pages were revamped.

Version 1.8.4 includes some functions for parallel computations, and some functions for Topological Data Analysis.

Version 1.8.6 includes some functions for topological data analysis. The function ModPCohomologyRing() has be speeded up. There is also now a function for the cover of a (non-nilpotent) Lie algebra.

Version 1.8.8 includes the notion of a cocycle with coefficients in a G-module (= abelian G-outer group group). It contains a function for writing a resolution to a file. It also contains the beginning of functionality for handling homological algebra at the abstract level of abelian categories.