(C) Graham Ellis 2005-2006


	The HAP package for group cohomology and related functors
        ---------------------------------------------------------

"HAP" is a package for some basic calculations in the cohomology of finite 
and infinite groups. A full description of the library can be found from the 
html file Hap1.7.4/www/index.html .

"HAP" is written almost entirely in the GAP language. A few of HAP's (optional) 
functions rely on Polymake software (available from 
www.math.tu-berlin.de/polymake/) which should be installed so that it starts 
using the command "polymake" at the Linux prompt. A few (oprional) functions
rely on Graphviz software (available from http://www.graphviz.org/).

Please send your bug reports to graham.ellis(at)nuigalway.ie .


                     Installing HAP 
                     --------------

On a Linux machine with GAP (and optionally Polymake) installed, the HAP 
library can be loaded as follows:
 
* First download the file hap1.7.4.tar.gz to the subdirectory "pkg/" of GAP. (If 
you don't have access to this, then create a directory "pkg" in your home 
directory and download the file there.)

* Change to directory "pkg/" and type "gunzip hap1.7.4.tar.gz" followed by 
"tar -xvf hap1.7.4.tar" .

* Start GAP. (If you have created "pkg" in your home directory then start GAP 
with the command "gap -l 'path/homedir;' "   where path/homedir is the path to 
your home directory.)

* In GAP type " LoadPackage("HAP"); " .

* Help on HAP can be found on the HAP home page (a version of which is included in directory "pkg/Hap1.7.4/www" of this distribution).

* Performance can be significantly improved by using a compiled version of the 
HAP library. A compiled version can be created by the following steps.

(1) Change to the directory "pkg/Hap1.7.4/" .
(2) Edit the file "compile" so that: PKGDIR is equal to the path to the 
directory "pkg" where your GAP packages are stored; GACDIR is equal to the 
path to the directory where the GAP compiler "gac" is stored.
(3) Type "./compile" . 

The next time HAP is loaded a compiled version will be loaded.

* Should you want to return to an uncompiled version, change to the directory
"pkg/Hap1.7.4/" and type "./uncompile".
