Ways to download and install the software

The options, in order of preference, are:

Download the source code and compile it yourself

Download source code in a single file

This is the latest stable version.

Version 1.0.8 atlas_1.0.8.tgz source code for Fokko and atlas including messages and atlas-scripts

Download the source code using git

For users who are not familiar with git, see Help with git to get started with git.

If you choose to use git, you can get the most up-to-date version of the software. Open a terminal window (in the Finder click Macintosh/Applications/Utilities/Terminal). Make sure your git client is relatively new. Version and above should work.

To check your git version, on the command line, do:

git --version

Choose a directory on your machine to store the source code. Use your terminal to navigate into that directory, then type:

git clone

This creates a subdirectory “atlasofliegroups” and stores the files there.

Compiling from source

After you have the source code, cd to the atlasofliegroups directory.

Compiling atlas for the Mac using Homebrew

To compile atlas on a Mac you need to install a C++ compiler (the default Mac compiler is not up to the task). Homebrew is a package manager for the Mac, which is an alternative to the more standard MacPorts. Homebrew is the preferred method. Alternatively see Compiling atlas for the Mac using MacPorts.

Install Homebrew

Go to Homebrew and follow the instructions there to install Homebrew.

(This is a single command /usr/bin/ruby… executed in a terminal window)

Install the C++ compiler

Open a terminal window and give the commands

brew install gcc49


brew install readline

Edit two Makefiles

cd to the directory where you downloaded the source code. Edit the file Makefile to replace CXX = g++ -std=c++0x with:

CXX = /usr/local/Cellar/gcc@4.9/4.9.3_1/bin/g++-4.9 -std=c++0x

The correct path for you might be slightly different from this. cd to /usr/local/Cellar and find a file …/bin/g++… and use this. Also make the following changes: add -L/usr/local/opt/readline/lib to the end of two lines as follows:


LDFLAGS := $(LDFLAGS) $(rl_libs) -L/usr/local/opt/readline/lib


LDFLAGS := $(rl_libs) -L/usr/local/opt/readline/lib


Also make the first change

CXX = /usr/local/Cellar/gcc@4.9/4.9.3_1/bin/g++-4.9 -std=c++0x

to the file ./sources/interpreter/Makefile

Enable readline

Give the command

brew link –force readline

to install some symbolic links necessary for readline


Give the command


To compile atlas and Fokko, with readline.

Other Compilation options:

We recommend compiling with:

make atlas verbose=true optimize=true

The option “verbose” makes atlas print a little more information about what it is doing, like printing a counter during a long Kazhdan-Lusztig computation. The option “optimize” tells the compiler to work hard to make the code as fast as possible; this takes slightly longer to compile, then runs maybe 10% faster.

Other possibilities are:


The option “debug” makes the software report bad things (for example, negative coefficient in a KL polynomial) that aren’t supposed to happen, to detect code problems early.

Installing Fokko and atlas

To install the executables in [installation directory] and put symlinks in [binary directory], type:

make install INSTALLDIR=[installation directory] BINDIR=[binary directory]

The default BINDIR is INSTALLDIR/../bin


To install the executables in /usr/local/atlas, and symlinks in /usr/local/bin, type:

sudo make install INSTALLDIR=/usr/local/atlas

(This example only works up to OS 10.10, and you need root access).


To install the executables in /home/[userid]/software/atlas, and symlinks in /home/userid/bin, type:

make install INSTALLDIR=/home/[userid]/software BINDIR=/home/[userid]/bin

Say you unpacked the software in /home/[userid]/atlas_0.7. To leave the software there, and create symlinks in /home/[userid]/bin, type:

make install

Next: see Running Atlas

Installing cwebx

The software cwebx is needed to compile atlas. If you downloaded a tgz file from the downloads page, you should not need to install cwebx. If you downloaded the software from github using git, then cwebx is included in the directory cwebx, or available from

Running make in the directory cwebx should compile cwebx, and produce the executables cweb/ctanglex and cweb/cweavex. The file sources/interpreter/Makefile tells the compiler to look for these executables. If you move the cwebx directory, or want to use different versions, you must edit this Makefile.

You need to have a working copy of tex in your PATH to run cweavex.

Using Docker

The preferred method is to compile the software from source.

The next choice is using the Docker container system.

This installs a container, which is a self-contained linux environment (similar to a virtual machine) and runs the software in the container. This is less dependent on the details of your system, and is a good option of you have trouble compiling the software yourself. It requires adminsitrative privileges, so is mainly used for personal machines, and not instutional machines under the control of a system administrator.

Install docker (community version) for your system from Double click on the dmg file to install it. This requires typing your password.

Open a terminal window and give the command

docker run -it jeffreyadams/atlasofliegroups

to download the software and run it (it launches atlas and read in the fill The first time you do this it takes up to a few minutes. Subsequent times it is much faster.

To get the latest update, give the command

docker pull jeffreyadams/atlasofliegroups

Download and Install an executable

The best method is to compile from source. As a backup option you can download install an executable file.

Download a copy of the executable, and the atlas-scripts directory here:

Mac compiled atlas_mac_pre_1.01.tgz executable, and messages atlas-scripts directories

Double-click on the file to extract it.

Open a terminal window, and cd to the directory where the files were downloaded.

Make the file executable:

chmod u+x atlas

Run the software with the command:

./atlas  --path=atlas-scripts all

The path argument tells atlas where to find the scripts, and all says to load most of the scripts (not including a few which are under development). (Double-clicking on the file will launch the application, but will not make the atlas-scripts available.)