The ACE package
The ACE package provides functions associated with Todd-Coxeter coset
enumeration by interfacing with the Advanced Coset Enumerator (ACE),
ACE coset enumerator (C) 1995-2001 by George Havas and Colin Ramsay
from within GAP 4.
The GAP interface (package) has been written by Alexander Hulpke and Greg
Gamble. In order to install the ACE package you must get the archive file
ace-XXX.tar.gz, for some version number
XXX, (which includes the C
source code of Havas and Ramsay).
The ACE package provides a mechanism to replace GAP’s usual Todd-Coxeter
coset enumerator by ACE, so that functions that behind the scenes use coset
enumeration will use the ACE enumerator. The ACE enumerator may also be used
explicitly; both non-interactively and interactively. However the package is
used, a plethora of options and strategies are available to assist the
user in avoiding incomplete coset enumerations.
You can download
XXX is the package version
number) from the home page for the ACE package
or via the GAP web site
If you prefer .zip or tar.bz2 to tar.gz archives, substitute the appropriate
suffix in the above paths.
Since the ACE package interfaces to an external binary, it is only usable in
an environment that supports compiling of the binary, e.g. a UNIX or a
Installing the ACE package
To install the ACE package, move the file
ace-XXX.tar.gz into the
directory in which you plan to install ACE. Usually, this will be the
pkg in the hierarchy of your version of GAP 4. (However, it is
also possible to keep an additional
pkg directory in your private
directories, see section “ref:Installing GAP Packages” of the GAP 4
reference manual for details on how to do this.)
ace-XXX.tar.gz, which in most Linux environments can be done
Go to the newly created
is the path to the GAP home directory. So for example if you install
the package in the main `pkg` directory call
In fact `../..` is the default path. So, if this is correct, you may omit
it. This will fetch the architecture type for which GAP has been compiled
last and create a `Makefile`. Now simply call
to compile the binary and to install it in the appropriate place.
Note that the current version of the configuration process only sets up
directory paths. If you need a different compiler or different compiler
options, you need to edit `src/Makefile` prior to calling `make`
If you use this installation of GAP on different hardware platforms you
will have to compile the binary for each platform separately. This is
done by calling `configure` and `make` for the package anew immediately
after compiling GAP itself for the respective architecture. If your
version of GAP is already compiled (and has last been compiled on the
same architecture) you do not need to compile GAP again, it is sufficient
to call the `configure` script in the GAP home directory.
That's it. Now start GAP and type
The ACE banner should appear on the screen.
For details on how to use the ACE package see the package documentation
in the `doc` subdirectory (view either `manual.dvi` via `xdvi` or
`manual.ps` via `ghostview` or `manual.pdf` via a PDF viewer), which
gives information on how to use ACE from within GAP. The ACE user manual
(`ace3001.ps` or `ace3001.pdf`) in the `standalone-doc` directory,
explains how to use the ACE binary (i.e. the C program that is interfaced
with by the package from within GAP) as a stand-alone.
The `src` subdirectory contains a copy of the C source code for ACE. The
only modification are those listed in src/CHANGES. In particular, the
the following bug was fixed on 25 February, 2001.
A bug was discovered in ACE 3.000 on 22 December, 2000 that was
particularly manifested by the Linux gcc compilers listed below. The bug
was reported with fix by Volker Gebhardt (thanks!) and caused a
segmentation fault when ACE output coset representatives. The fix is
incorporated in ACE 3.001 which we now use.
ACE has been compiled successfully with the following C compiler:
gcc version 4.8.4 (Ubuntu 4.8.4-2ubuntu1~14.04.1)
and is presumed to compile with any modern version of C compiler.
If you encounter problems with the ACE binary, please contact one of the
C code authors: George Havas <firstname.lastname@example.org> or Colin Ramsay
If you encounter problems at the GAP level, please submit an issue to
When sending a bug report, remember we will need to be able to reproduce
the problem; so please include:
* The version of GAP you are using; either look at the header when
you start up GAP, or at the gap> prompt type: VERSION;
* The operating system you are using e.g. Linux, macOS, Windows, ...
* The compiler you used to compile ACE and the options you used.
Type: gcc -v or: cc -version, and look in src/Makefile for the
value of CC to find out.
* A script, either in GAP or standalone ACE, that demonstrates the
bug, along with a description of why it's a bug (e.g. by adding
comments to the script - recall, comments, both in GAP or
standalone ACE, begin with a #).
ace directory and call
configure <path> where