Gull 3 Linux+Syzygy and Fathom released.

[basil00]

Gull 3 Linux+Syzygy is now available from here: https://github.com/basil00/Gull

This is a completely new implementation of Gull syzygy, and is not related to the previous syzygy patch.

Gull+syzygy showed improvement over straight non-syzygy Gull:

Code: Select all

Gull 5-man syzygy (4000 games) using 60"+0.4" 2-threads:
Score: +673-565=2762
Winning fraction: 0.5135
Elo difference: +9.38304
LOS: 0.998928

The syzygy patch uses a new mini-project called Fathom available here:
https://github.com/basil00/Fathom

Fathom is a standalone version of Ronald de Man's syzygy probing code. The original probing code depended on Stockfish functionality, and this must be replaced in order to integrate into a different engine. This is not so easy for an engine like Gull, which is different and does not have well-documented code.

Fathom aims to ease integration by making the probing code engine-independent. Basic integration is therefore reduced to three API calls: initialization, WDL-probe during search, and root-probe at the root.

As an example, the Gull Fathom patch is here: https://github.com/basil00/Gull/commit/ ... efdccaec0c

Although Fathom can be engine independent, some functionality can be replaced by the engine's code for better efficiency. This is optional, see the Gull patch above for an example.

Fathom can also be used for other projects, e.g. syzygy tablebase adjudication. This may be useful for GUIs. The Fathom repository also includes a stand-alone command-line tool for mapping FEN position strings to table-base results.

[Ferdy]

Thanks for sharing.

[cdani]

Nice work! Thanks!

[Jesse Gersenson]

Way to go Basil! And, Thanks.

[whereagles]

LOS = statistical level of significance?

[basil00]

LOS = statistical level of significance?

LOS = Likelihood Of Superiority.

[whereagles]

thx.

[MikeB]

Gull 3 Linux+Syzygy is now available from here: https://github.com/basil00/Gull

This is a completely new implementation of Gull syzygy, and is not related to the previous syzygy patch.

Gull+syzygy showed improvement over straight non-syzygy Gull:

Code: Select all

Gull 5-man syzygy (4000 games) using 60"+0.4" 2-threads:
Score: +673-565=2762
Winning fraction: 0.5135
Elo difference: +9.38304
LOS: 0.998928

The syzygy patch uses a new mini-project called Fathom available here:
https://github.com/basil00/Fathom

Fathom is a standalone version of Ronald de Man's syzygy probing code. The original probing code depended on Stockfish functionality, and this must be replaced in order to integrate into a different engine. This is not so easy for an engine like Gull, which is different and does not have well-documented code.

Fathom aims to ease integration by making the probing code engine-independent. Basic integration is therefore reduced to three API calls: initialization, WDL-probe during search, and root-probe at the root.

As an example, the Gull Fathom patch is here: https://github.com/basil00/Gull/commit/ ... efdccaec0c

Although Fathom can be engine independent, some functionality can be replaced by the engine's code for better efficiency. This is optional, see the Gull patch above for an example.

Fathom can also be used for other projects, e.g. syzygy tablebase adjudication. This may be useful for GUIs. The Fathom repository also includes a stand-alone command-line tool for mapping FEN position strings to table-base results.

Mac compile also works. Thx. Is it supposed to use 5 man syzygy - does not seem to picking that up? 4 man syzygy table bases are working.

[d] 4k3/8/8/8/7q/8/3Q4/R3K3 w Q - 3 1 if playing white, does not pick up mate score. Komodo here will show mate score. I have syzygy table base in two different directories - could that be an issue? Here is the polyglot.ini:

Code: Select all

[PolyGlot]


[Engine]

SyzygyPath=/volumes/RAMDisk/tablebases:/applications/tablebases

[stuwph]

yes, cool new toy

Compiling under Windows for me needed inserting #include <intrin.h> at top of windows.h to avoid an "__cpuid was not declared in this scope" error

After some first tests it looks that syzygy for now only works up to 5men, initializing 6men makes the engine crash, at least in Chessbase and Arena gui.

And the "SyzygyPath" option doesn't show up in Chessbase, however it does in Arena.

It will be great fun if you extend your nice work further on!
besides my skills in doing that are way too limited...

[stuwph]

inserting #include <intrin.h> at top of windows.h

-> at top in windows.cpp