Arasan 17.1

[jdart]

Arasan 17.1 is available from http://www.arasanchess.org.

Changes in Arasan 17.1:
1) Scoring changes: connected passer code, knight and bishop
piece square tables, new king safety scoring.
2) Add special-case eval code for K vs K+R and K vs K+Q endgames.
3) Bug fix: validate hash move in q-search before using it.
4) Changes to handling of book selectivity option.
5) Adjust variable strength option so bottom end of strength scale
is lower (will blunder sometimes).
6) Increase ply depth in reduced strength mode for very low material
endgames (engine was having difficulty mating in these cases
even at moderate strength settings). This also fixes some
problems with playing into stalemate.
7) Better handling of out-of-memory errors when allocating hashtable.
8) GUI fix: initialize all engine options at start of game. Fixes
problem with resignation setting not being obeyed.
9) GUI fix: clear any previous game result and other details after
loading a position file.

This version also has significant changes to the opening book. Overall it is measurably stronger than 17.0 but it is not a huge difference.

--Jon

[Graham Banks]

Thanks Jon. Hope you're right about it being stronger.

[F.Huber]

Arasan 17.1 is available from http://www.arasanchess.org.

Thanks, but 'arasanx-32.exe' is once again a 64-bit version (in the installer and in the ZIP file).

Franz

[jdart]

Should be fixed now - please try downloading again.

My only box with XP 32-bit died so I can't even test this stuff anymore.

--Jon

[F.Huber]

Should be fixed now - please try downloading again.

Yes, now it's the correct 32-bit engine again (at least in the ZIP package).

Thanks,
Franz

[Norbert Raimund Leisner]

Windows Installer v17.1 runs on XP SP3 32-bit too

20 years chess programming of Arasan, congratulations Jon!

Norbert

[Sylwy]

Overall it is measurably stronger than 17.0 but it is not a huge difference.

--Jon

Sorry, extremely sorry !

See,please:

http://www.talkchess.com/forum/viewtopi ... 31&t=50060

Silvian R

[Graham Banks]

Overall it is measurably stronger than 17.0 but it is not a huge difference.

--Jon

Sorry, extremely sorry !

See,please:

http://www.talkchess.com/forum/viewtopi ... 31&t=50060

Silvian R

They're pretty close in strength, so it's a bit early to know for sure which of the two is slightly stronger.