
The GAP 4 package `Alnuth'
==========================

This package provides an interface between GAP 4 and KANT respectively
KASH, the shell of the computational algebraic number theory system KANT. By
now the interface can only be used on a Linux system. KASH itself is not part
of this package.  It has to be obtained and installed independently of this
package. Alnuth works with KASH version 2.4 or higher.


Getting and installing Kash
===========================

KASH is available at

           http://www.math.tu-berlin.de/~kant/download.html

Note that you have to download two files for a complete installation
of KASH. For the installation of version 2.5 of KASH on a Linux
system you would do the following steps:

--- Download the files
    kash_2.5.common.tar.gz and kash_2.5.3.linux.tar.gz
    into the same directory on your system.
 
--- Unpack the files using tar.  This will create a directory
    KASH_2.5 containing among other files the KASH executable called
    kash.

The place where KASH is located in your system is independent of the place
where the Alnuth-package is installed.


Installing this package
=======================
 
This package is available at

           http://www.icm.tu-bs.de/ag_algebra/software/assmann/Alnuth
 
in form of a gzipped tar-archive or as an uncompressed tar-archive.
 
There are two ways of installing the package. If you have permission
to add files to the installation of GAP 4 on your system you may
install the Alnuth-package into the `pkg' subdirectory of the GAP
installation tree.  If you do not have the permission to do that you
may install the Alnuth-package in your private area. In the latter case you
need to have a directory named pkg in your private area (for details see
74.1 Installing a GAP Package in the reference manual). 

--- Now move the alnuth.tar.gz of alnuth.tar file into the directory pkg
    and unpack it:

    bash> tar xfz alnuth.tar.gz        # for the gzipped tar-archive
    bash> tar xf alnuth.tar         # for the uncompressed tar-archive

--- Adjust the path of the executable for KASH

    The package needs to know where the executable for KASH is. In the default
    setting Alnuth will check if there is an executable called `kash' in your
    search path. 
    
    If you do not want to use the default setting, then there are three other
    possibilities.

    If you are able to edit the file `pkg/alnuth/defs.g' you can change the line

    BindGlobal( "KANTEXEC", Filename( DirectoriesSystemPrograms( ), "kash" ));

    to something like

    BindGlobal( "KANTEXEC", "mykash/kash -l mykash/lib" );

    where `mykash' needs to be replaced with the directory where KASH
    was installed.

    Like always you can also change your personal `.gaprc' file (see 3.4 The
    .gaprc file) for setting the variable KANTEXEC to a proper value. To do
    this add the command line mentioned above to `.gaprc'.

    The third possibility is to change the path to the executable within GAP
    using one of the two functions `SetKantExecutable' and
    `SetKantExecutablePermanently'.

    You will find more detailed expalanations in the manual.
 
  
Loading and testing the package
===============================

To use this package you have to request it explicitly. This is done by calling

    gap> LoadPackage("alnuth");
    Loading Alnuth 1.0 ...
    true
    gap>

Once the package is loaded, it is possible to check the correct installation
by running the test suite of the package.

    gap> ReadPackage( "Alnuth", "tst/testall.g" );









