CapAndHomalg.jl 

Simplified access to the repositories of the GitHub organization homalg-project

Documentation	Build Status	GitHub Actions

Introduction

The Julia package CapAndHomalg provides simplified access to the repositories of the GAP packages hosted on the GitHub organization homalg-project, most of which are based on the

• CAP project,
• homalg project.

These are open source GAP multi-package projects for constructive category theory and homological algebra with applications to module theory of commutative and non-commutative algebras and algebraic geometry.

Installation

Install Julia

To install Julia follow the first Steps 0 and 1 on our installation page.

Install CapAndHomalg.jl

Then start julia in a terminal and add the package CapAndHomalg:

julia> using Pkg; Pkg.add("CapAndHomalg")

julia> using CapAndHomalg

For more information on the included GAP packages see the documentation.

The correctness of the installation and the availability of the functionality can at any time be tested using

julia> using Pkg; Pkg.test("CapAndHomalg")

After each update of the Julia package GAP a rebuild is (probably) necessary:

julia> using Pkg; Pkg.build("CapAndHomalg")

Software dependency

CapAndHomalg relies on the

computer algebra systems	through the Julia packages
GAP	Gap.jl
Singular	Singular_jll.jl

all of which are components of the computer algebra system OSCAR.

Some of the bundled packages use the GAP packages

• IO
• ferret
• json
• QPA2

and the

third party software	through the GAP packages	and the Julia packages
Graphviz	dot-format generating code like in Digraphs	Graphviz_jll.jl
4ti2	4ti2Interface	lib4ti2_jll.jl

General Disclaimer

The software comes with absolutely no warranty and will most likely have errors. If you use it for computations, please check the correctness of the result very carefully.

This software is licensed under the LGPL, version 3, or any later version.

Funding

The development of this package and many of the GAP packages hosted on the GitHub organization homalg-project was partially funded by the DFG (German Research Foundation) through the

• Special Priority Project SPP 1489,
• Transregional Collaborative Research Centre SFB-TRR 195.