                   README file for the Gpd package
                   ===============================

Version 1.42, 15th February 2016  

Introduction
------------
This package allows for the computation of finite groupoids: both connected,
and with several components.  Graphs of groups and graphs of groupoids are
also constructed, allowing the calculation of normal forms for Free Products
with Amalgamation and for HNN extensions when the initial groups have
rewriting systems.

History
-------
Version 1.001 was called GraphGpd, and  formed part of 
Emma Moore's PhD thesis in December 2000.
Version 1.002 was prepared for the GAP 4.4 release in January 2004,
and deposited in the incoming directory on the St Andrews ftp server.
In the spring of 2006 the package was renamed Gpd and extensively 
rewritten, with documentation in GAPDoc format.
Version 1.01 was deposited in June 2006. 
Gpd became an accepted GAP package in May 2015. 
The latest version, 1.42, was released on 15th February 2016 for GAP 4.8. 
(In this temporary version there have been a number of changes of function 
name, such as IsDigraph becoming GpdIsDigraph. 
This is in order to avoid conflicts with the new Digraphs package.
Further changes will be made once the Digraphs package becomes part 
of the GAP distribution.) 
A more detailed history is included as Chapter 8 of the manual, 
and in the file CHANGES.

Distribution
------------
The Gpd package is distributed with the accepted GAP packages: see
     http://www.gap-system.org/Packages/gpd.html
It may also be obtained from the Bangor ftp pages for
Computational Higher-dimensional Discrete Algebra at:
  http://pages.bangor.ac.uk/~mas023/chda/gpd/

Copyright
---------
The Gpd package is Copyright {\copyright} Chris Wensley and Emma Moore, 
2000--2016. 
Gpd is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version. 
For details, see \URL{http://www.gnu.org/licenses/gpl.html}

Installation
------------
1) unpack `gpd-1.42.tar.gz' in the `pkg' subdirectory of the GAP root
   directory.
2) From within GAP load the package with:
gap> LoadPackage("gpd");
true
3) The documentation is in the `doc' subdirectory.
4) To run the test file read testall.g from the gpd/tst/ directory. 

Contact
-------
If you have a question relating to Gpd, encounter any problems, or have a suggestion for extending the package in any way, please 
 - email c.d.wensley@bangor.ac.uk 
 - or report an issue at https://github.com/gap-packages/gpd/issues/new 

