
The GAP Character Table Library
===============================

Description
-----------

This is the first release (Version 1.0) of the GAP Character Table Library
as an add-on package for both GAP 3.4 and GAP 4.
Up to GAP 4.2, the library of character tables had been distributed as an
inseparable part of the GAP distribution.
The aims of the restructuring of the code are the following.

- Upgrades of the GAP Character Table Library are now possible,
  independent of GAP releases,
  via the mechanism that has been used already for installing or upgrading
  GAP packages;
  each such upgrade will get a version number.

- The new directory structure provides an environment that is more suitable
  for the further development of the GAP library of character tables.

- It is easy to omit the character table library from the GAP 4 installation
  if one is not interested in it.

There is a manual in the subdirectory `doc' written in plain TeX,
an HTML version is available in the subdirectory `htm'.
It describes the available functions in detail.

If you have found important features missing or if there is a bug,
let us know and we will try to address it in the next version of the
GAP Character Table Library.
Please send a short email to

          Thomas Breuer    <sam@math.rwth-aachen.de>

This holds in particular if you have used the GAP Character Table Library
to solve a problem.

You can also reach the GAP developers by sending an email to the general
GAP email address for problems with GAP:

                     gap-trouble@dcs.st-and.ac.uk


Contents
--------

With this version you should have obtained this README file
and an archive file containing the GAP interface and the data files,
in the following files and directories:

        data            the directory with the data files
        doc             the directory with the TeX version of the manual,
                        and some example files in DVI format
        etc             the directory containing the script `maketbl'
        gap3            the directory with the GAP 3 code
        gap4            the directory with the GAP 4 code
        htm             the directory with the HTML version of the manual,
                        and some example files in HTML format
        init.g          the file that initializes the package
        read.g          the file that reads in the GAP 4 interface
        tst             the directory with some test files


Unpacking
---------

You may have got the GAP Character Table Library as
a zoo archive (filename ends with .zoo)
or a compressed tar archive (filename ends with .tgz).
In each case, use the appropriate command on your system to unpack
the archive.

On UNIX systems the zoo archive may be unpacked by

    zoo x ctbllib.zoo

which will unpack the archive into a directory `ctbllib' in the
current directory. 

On UNIX systems the compressed tar archive may be unpacked by

    tar xzf ctbllib.tgz

or, if tar on your system does not understand the option z, by

    gunzip ctbllib.tgz
    tar xf ctbllib.tar

which will in each case unpack the code into a directory `ctbllib'
in the current directory.

If your system does not have a zoo programme, you can pick up the
C-code for unzoo from the GAP web page and compile it on your system.
For this your system needs to have a C-compiler.
unzoo can be used to unpack the zoo archive, as follows:

    unzoo -x ctbllib.zoo

unpacks the archive into a directory `ctbllib' in the current directory.


Installation for GAP 4.3
------------------------

Installation of the GAP Character Table Library means unpacking the
archive file in an appropriate directory.

For the two ways of installing GAP 4 packages in general,
see the sections "Installing GAP Packages" and
"Installing a GAP Package in your home directory"
in the GAP 4 Reference Manual.

Once you have successfully installed the GAP Character Table Library,
it is usually loaded automatically when GAP is started;
if not then it can be loaded explicitly by typing

gap> RequirePackage( "ctbllib" );
true;
gap>

at the GAP prompt.
Then the functions of the table library are available in the current session.


Installation for GAP 3.4 or GAP 4.2
-----------------------------------

This is not much different from the installation for GAP 4.3,
the library is installed via unpacking the archive file in the `pkg'
directory of the GAP installation.

When GAP 3 or GAP 4.2 is started, the outdated character table library
is installed by default.
For replacing it by the new one, one has to type

gap> RequirePackage( "ctbllib" );
true;
gap>

at the GAP prompt.

If one wants to use the new character table library as the default,
one can put the `RequirePackage' statement into one's .gaprc file
(see the GAP Reference Manual for details).

The value of the global variable `TBLNAME' allows one to decide
which character table library is actually used.
Namely, it ends with "tbl/" if the outdated library is used,
and with "ctbllib/data/" if the new library is used.

The manual of the new character table library is intended for GAP 4.3,
in particular the cross-references refer to the GAP 4.3 Reference Manual.
So when using the new character table library with GAP 3.4 or GAP 4.2,
one should still consult the documentation of the character table library
contained in the Reference Manual of GAP 3.4 or GAP 4.2, respectively.

