This to inform you there is a new Glaurung, mainly for those interested in experimenting a bit with some different forms of pruning but not up to writing all the code. And I presume there may be some minor improvements in the code since the last version although Tord has not invested much time in writing new stuff and he expects no strength increase over Glaurung 2.1. Have not had the time to take a look at the sources myself. Jim Ablett already made a compile for Windows, thanks Tord and Jim!
Tord Romstad wrote:Hi all,
After the discussion in the thread "Hardware vs Software", where (among other things) the values of recursive null move pruning and late move reductions were discussed, I have made an experimental Glaurung version with UCI options for enabling/disabling null move pruning, late move reductions and the tapered "super qsearch" I use in the transitory phase between the main search and the qsearch. The three new options are called "Late Move Reductions", "Null Move Pruning" and "Super Qsearch", and they all have the default value "true".
The source code and a polyglot.ini file with the new options can be downloaded here.
This Glaurung version is published only for the benefit of those (if any) who wants to experiment with the three new options (setting any of them to "false" will almost certainly reduce the playing strength, but I have no idea by how much). Of course, you are also free to do whatever else you like with this version, but don't expect it to be significantly stronger than Glaurung 2.1. Almost nothing has changed (I don't do chess programming at the moment, and haven't touched my source code since May or June), and the strength should be more or less the same as for 2.1.
Debugging is twice as hard as writing the code in the first
place. Therefore, if you write the code as cleverly as possible, you
are, by definition, not smart enough to debug it.
-- Brian W. Kernighan
This to inform you there is a new Glaurung, mainly for those interested in experimenting a bit with some different forms of pruning but not up to writing all the code. And I presume there may be some minor improvements in the code since the last version although Tord has not invested much time in writing new stuff and he expects no strength increase over Glaurung 2.1. Have not had the time to take a look at the sources myself. Jim Ablett already made a compile for Windows, thanks Tord and Jim!
Tord Romstad wrote:Hi all,
After the discussion in the thread "Hardware vs Software", where (among other things) the values of recursive null move pruning and late move reductions were discussed, I have made an experimental Glaurung version with UCI options for enabling/disabling null move pruning, late move reductions and the tapered "super qsearch" I use in the transitory phase between the main search and the qsearch. The three new options are called "Late Move Reductions", "Null Move Pruning" and "Super Qsearch", and they all have the default value "true".
The source code and a polyglot.ini file with the new options can be downloaded here.
This Glaurung version is published only for the benefit of those (if any) who wants to experiment with the three new options (setting any of them to "false" will almost certainly reduce the playing strength, but I have no idea by how much). Of course, you are also free to do whatever else you like with this version, but don't expect it to be significantly stronger than Glaurung 2.1. Almost nothing has changed (I don't do chess programming at the moment, and haven't touched my source code since May or June), and the strength should be more or less the same as for 2.1.
gerold wrote:
Thanks for the post and thanks to Tord and Jim who is always on
the ball. This is a nice program to learn from.
Best to you,
Gerold.
Yes, Agreed!
"Good decisions come from experience, and experience comes from bad decisions."
__________________________________________________________________
Ted Summers
This version is actually about half a year old (according to my Darcs log, the last change was made on June 10), and contains very little new compared to Glaurung 2.1. The most important change is the addition of a simple evaluation term for space, but because it is completely untested and untuned, it probably doesn't improve the playing strength, and may even harm it a little. I would be extremely surprised if this version performs significantly better than Glaurung 2.1, and not at all surprised if it is slightly weaker.
The reason for releasing this version was a discussion on the "Programming and Technical Discussions" sub-forum, where Bob made some experiments with Crafty to find out how much recursive null move pruning and late move reductions were worth in terms of Elo. Uri thought it would be interesting to see the experiment repeated with Glaurung, so I made a special Glaurung version where null move pruning and LMR can easily be switched on and off.
Testing this version for the CEGT or CCRL rating list or including it in tournaments is probably a waste of time. I don't recommend it, but of course I won't object if somebody wants to try.
