Amy is a chess playing program like crafty or gnuchess. It probably is a bit stronger than gnuchess and not quite as strong as crafty. It is compatible with xboard, uses endgame table bases and an opening book.

Amy is distributed under the BSD 2-Clause License. You should find a file 'LICENSE' in the Amy distribution containing this license.

Please note that Amy uses table base code developed and copyrighted by Eugene Nalimov. This code is not under the BSD License.

On Un*x or Linux systems this is very simple:

./configure
make

should do it. Make sure to specify compiler options with good optimization, I typically use something like (assuming a bash or ksh shell):

export CFLAGS='-O2 -mpentium -fomit-frame-pointer'
export CXXFLAGS=$CFLAGS
./configure
make

Note that the '-mpentium' option only works with newer versions of gcc/egcs. If you are using an older version, chances are that this option wont work - use '-m486' instead.

On Windows systems:

Thanks to Dann Corbit (dcorbit@solutionsiq.com) Amy will now compile under Windows. Please do not ask me any details about how to get this going.

Amy uses ABDADA as a parallel search algorithm. Please see 'search.c' for reference. To enable ABDADA pass the "--enable-mt" to configure.

Note that you need 'POSIX THREADS' on your system to use the parallel search.

Just type 'Amy'. You can also specify a hashtable size:

Amy -ht 10m

will use 10 MB of hashtables. If you build a parallel version, you can supply the number of processors (or threads rather) Amy should use:

Amy -ht 10m -cpu 2

Note that you can specify these options via an '.amyrc' file, too. See below.

You will need Berkeley DB (see http://www.sleepycat.com). I am using version 2.7.3 - older version might give you trouble. If the Berkeley DB Files are installed in standard locations './configure' will detect Berkeley DB automatically. If it does not, use

./configure --with-tbpath=<path to Berkeley DB>

To create a book from a PGN file, first create the ECO database. At Amy's prompt, type 'eco PGN/eco.pgn'. Verify that it works: Type

new
force
e4
e

the output should be

Eco code is B00 King's pawn opening

You can now use the 'bookup' command to create an opening book from a PGN file:

bookup ClassicGames.pgn

This command will create an opening book from the file "ClassicGames.pgn".

Since book files tend to become very large, you can make them smaller by using the 'flatten' command. Typing

flatten 1

will create a file 'Book2.db' which contains all positions from 'Book.db' which occured more than one time. This typically reduces book size to 1/10th! To use the new book, simply rename it to 'Book.db' and restart Amy.

You want Amy to play King's gambit no longer? No problem! Just create a file containing the lines

e4 e5 f4?

and use

prefs filename

to read it in. Amy comes complete with a file 'Preferences' which avoids some opening traps and known bad lines. Just use

prefs Preferences

to set these.

Starting with version 0.8.4 Amy features a simple version of book learning. It uses the autosave files created by Amy to update the opening book statistics. For this to work, game autosaving must be activated (see section "Setting options via .amyrc").

Create a directory called 'TB' in the distribution directory. Put your tablebase files there. They will be recognized automagically. See also the section on '.amyrc' below.

Amy supports an .amyrc file to set several options. The .amyrc file should be in the current directory when starting amy. Here is a sample .amyrc:

ht=20m

tbpath=/space/TB

cpu=2

autosave=true

Since people using Windows have reported that they have to resort to DOS mode for creating a .amyrc file, Amy also looks for Amy.ini.

• to Dann Corbit for porting Amy to Win32

• to Allen Lake for tuning Amy's timing algorithm