Download ScrZebra


ScrZebra is an abbreviation of SCRiptable endgame solver ZEBRA. It is a standalone program which runs in a command window under Windows 95/98/ME/NT/2000/XP or Linux and solves a list of positions WLD or for exact score. The same endgame solver as in WZebra is used.


The Othello endgame script format was devised by Raphael Schreiber , Stéphane Nicolet and myself and is as follows:

As an example, consider the following minimalistic example file:

% Here's a bunch of lopsided positions
XO---XXX-OOO-OOO-OOOOOO---OOXO---OOXOOO-OOXOOOOOXXXXX---XXXXXX--    X  % Comment for position 1
OOOOOOOOOOOOOOOXOXOXXXX-OOOOXX-OOOOOXX--OOXXO---OX--XO--X-------    X  % Do close positions exist in Othello?
XXOOOOOO-XXXXX-O-XXXXXXOOXOOXXOXOOXOXOXXOXOOOO--O-XO------------    X  % Comment for position 3
---O-----OOOO---XO-OOO--XOOOOO-XXOXXXOO-XOOXXOOOOOXOXXO-OXOOOOO-    X  
-----------------------O--OOOOO---OOOOOXOOOOXXXX--XXOOXX--XX-O-X    X
--XXXXX---XXXX---OOOXX---OOXXXX--OOXXXO-OOOOXOO----XOX----XXXXX-    O  % Ah! This one is closer.
% End of the endgame script


The action taken by the program when given an input file in the above format is as follows:


Four possible outputs corresponding to the input above are:


To run scrZebra, download the Windows or Linux archive below and unpack it into a directory which contains the file coeffs2.bin which you either can download separately here or copy from the WZebra directory if you already have downloaded WZebra 2.0 or higher from this page.

NameSizeLast changedContents
scrz.zip 165kB October 2, 2006 Windows
scrzl.tar.gz 320kB January 3, 2003 Linux

The archive contains the following files:
NameContents
scrzebra.exeThe solver.
ffotest.scrScript file for the FFO test.

Note: The latest scrZebra uses MMX instructions and hence does not run on the oldest Pentium processors.


scrZebra is run from a command window and the syntax is as follows:

  scrzebra [-e <echo output?>]
           [-h <hash size>]
           [-wld <wld only>]
           [-line <store line?>]
           [-b <use opening book?>]
           -script <input script> <output file>
The basic mode of operation, solving a set of positions for exact score, can be performed as follows:
  scrzebra -script mygames.scr mygames.out

The command-line options can be given in any order and are interpreted as follows:

-e <echo Zebra output?> optional
This switch controls if the board positions and Zebra's intermediate results are output when the script is analyzed; -e 1 (default) enables output while -e 0 disables it.

-h <hash table size> optional
The number of bytes in the hash table is 16*2^N if -h N is given. Default is N=18, i.e., a 4MB hash table.

-wld <wld only?> optional
This switch toggles if the positions are solved WLD or for exact score; -wld 0 (default) gives exact score while -wld 1 gives WLD only.

-line <store line?> optional
This switches toggles if optimal (when solving for exact score) or semi-optimal (when solving WLD) lines are written to the output file as described below. -line 1 enables this mode of operation while -line 0 (default) disables it.

-b <use opening book?> optional
This switches specifies if the opening book file book.bin will be read and its contents used when solving. Default is not to read the book file, corresponding to -b 0, while -b 1 enables use of the book.

-script <input script> <output file>
This mandatory switch specifies the script containing positions to solve and the output file to which the results are written.


Legal stuff

The program is freeware and may be copied freely as long as no modifications are made. It may not be used for any commercial purposes without the explicit consent of its creator.


Last modified October 2, 2006 by Gunnar Andersson

gunnar@radagast.se