Author: Michel Langeveld
Date: 12:43:19 11/27/01
Go up one level in this thread
On November 26, 2001 at 21:42:26, Dann Corbit wrote:
>On November 26, 2001 at 17:55:23, Michel Langeveld wrote:
>
>>On November 25, 2001 at 15:07:16, Tony Werten wrote:
>>
>>>On November 25, 2001 at 11:30:51, Michel Langeveld wrote:
>>>
>>>>Fixed some errors in the passer code...
>>>>
>>>> //grouping rule
>>>> //isolated pawns
>>>> //passers
>>>> //double and triple pawns
>>>> bool whiteGroup = false;
>>>> bool blackGroup = false;
>>>> int whiteGroups = 0;
>>>> int blackGroups = 0;
>>>> bool whiteIsolated = false;
>>>> bool blackIsolated = false;
>>>>
>>>> for (int i=0; i<8; i++)
>>>> {
>>>> if (evalStructure.whitePawnsPlace[i] > 0)
>>>> {
>>>>
>>>> //double pawns
>>>> if (evalStructure.whitePawnsPlace[i] == 2)
>>>> {
>>>> score -= PAWNDOUBLE_PENALTY;
>>>> }
>>>> if (evalStructure.whitePawnsPlace[i] == 3)
>>>> {
>>>> score -= PAWNTRIPLE_PENALTY;
>>>> }
>>>>
>>>> //passer?
>>>> if (evalStructure.blackPawnsPlace[i] == 0)
>>>> {
>>>> if (
>>>> (i != 0 &&
>>>> evalStructure.blackPawnsPlace[i-1] == 0 &&
>>>
>>>connected passed pawns don't pass this test
>>>
>>>> evalStructure.whitePawnsPlace[i-1] > 0 &&
>>>> evalStructure.blackPawnsPlace[i-2] == 0) ||
>>>
>>>How are passed pawns and not having a pawn 2 files away related ? BTW i-2 can
>>>become -1 here, hope your array runs from -1 to 8.
>>
>>I also evaluate pawns 2 further than the current pawn because I had big problems
>>with evaluation the following pawn structure.
>>
>>[D] 8/pppp4/8/8/8/8/P1PP4/8 w - - 0 1
>>
>>How many passed pawns does white have....?
>>
>>p.s.1 yes there's a bounce problem in my code. I programmed it in by purpose to
>>gain some extra speed. But fixed it later again.
>>p.s.2 I'm not sure what you meant by the connected passed pawns comment. Can you
>>give an example?
>
It's just a algoritm to evaluate pawns regardless of where are the kings.
It gives some slight positional bonusses and so it tries to grow to that
position if this is the only positional thing.
You are right that the real answer of a position withotu a search is not all
that. The position of the king is very important. Most of the time in endgame in
the middle of the board is good and in the side or even worse at the corner is
worse.
So maybe a kingsquaretable and this pawn evaluation code solves the epd's of you
at 1 ply search.
Michel
Michel
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.