Author: Robert Hyatt
Date: 11:27:06 10/18/01
Go up one level in this thread
On October 18, 2001 at 14:23:44, Rafael Andrist wrote:
>On October 18, 2001 at 14:20:39, Dann Corbit wrote:
>
>>On October 18, 2001 at 10:47:50, Rafael Andrist wrote:
>>
>>>On October 18, 2001 at 08:51:56, Robert Hyatt wrote:
>>>
>>>>On October 17, 2001 at 17:49:39, Robert Hyatt wrote:
>>>>
>>>>>On October 17, 2001 at 13:05:35, Roy Eassa wrote:
>>>>>
>>>>>>On October 17, 2001 at 13:02:34, Robert Hyatt wrote:
>>>>>>
>>>>>>>On October 17, 2001 at 11:15:12, Robert Hyatt wrote:
>>>>>>>
>>>>>>>>definitely a bug of some sort...
>>>>>>>
>>>>>>>A pretty simple bug in fact. I just fixed it in the 18.12 source and
>>>>>>>re-copied the source to the ftp machine. If you want to try the fix,
>>>>>>>feel free. There was a bad calculation that failed when the king was within
>>>>>>>one square of the rook-file promotion square, and the pawn was within one square
>>>>>>>of the promotion square, and the pawn was to move first...
>>>>>>
>>>>>>
>>>>>>Was the bug only in 18.12, or was it also in previous versions?
>>>>>
>>>>>
>>>>>Been there a while... Nothing has been changed here for several versions. I
>>>>>am completely rewriting the EvaluateDraws() code and have changed the name to
>>>>>EvaluateWinner(). It returns a bitmask of two bits, 01 means white can win
>>>>>only, 10 means black can win only, 11 means either can win, and 00 means dead
>>>>>drawn.
>>>>>
>>>>>It also recognizes a few more cases. I temporarily deleted the 18.12 source
>>>>>as I want to fix this completely as part of the final 18.12 release. I hope to
>>>>>finish it tonight...
>>>>
>>>>
>>>>New version is now available. It at least handles the test position for this
>>>>thread correctly. The search is more "stable" in the endgame as well, now.
>>>
>>>Did you include this KBP-KP case or did you only fix the bug in the evaluation
>>>of KBP-K endgames? Do you also handle cases, where the defending king is near
>>>enough, but can be forced to go away? E.g.
>>>
>>>[D]5k2/8/3K3P/8/8/8/2B5/8 w - - 0 1
>>
>>EPD Kit revision date: 1996.04.21
>>unable to open book file [e:\crafty\release/books.bin].
>>hash table memory = 192M bytes.
>>pawn hash table memory = 80M bytes.
>>EGTB cache memory = 32M bytes.
>>draw score set to 0.00 pawns.
>>choose from book moves randomly (using weights.)
>>choose from 5 best moves.
>>book learning enabled
>>result learning enabled
>>position learning enabled
>>threshold set to 9 pawns.
>>5 piece tablebase files found
>>19045kb of RAM used for TB indices and decompression tables
>>
>>Crafty v18.12
>>
>>White(1): st 60
>>search time set to 60.00.
>>White(1): setboard 5k2/8/3K3P/8/8/8/2B5/8 w - -
>>1. Bb3 Ke8 2. h7 Kd8 3. h8=Q#
>>White(1):
>
>What do you want to say? It's clear that it is very easy using EGTB.
>
>Rafael B. Andrist
No egtb's
2 0.00 0.00 1. Ke6 Kg8
2 0.00 ++ 1. Bb3!!
2 0.00 12.04 1. Bb3 Ke8
2-> 0.00 12.04 1. Bb3 Ke8
3 0.00 ++ 1. Bb3!!
3 0.00 13.05 1. Bb3 Ke8 2. h7 Kd8 3. h8=Q#
3-> 0.00 13.05 1. Bb3 Ke8 2. h7 Kd8 3. h8=Q#
4 0.00 ++ 1. Bb3!!
4 0.00 Mat03 1. Bb3 Ke8 2. h7 Kd8 3. h8=Q#
4-> 0.01 Mat03 1. Bb3 Ke8 2. h7 Kd8 3. h8=Q#
5 0.01 Mat03 1. Bb3 Ke8 2. h7 Kd8 3. h8=Q#
5-> 0.04 Mat03 1. Bb3 Ke8 2. h7 Kd8 3. h8=Q#
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