Author: Tony Werten
Date: 13:57:49 11/27/01
Go up one level in this thread
On November 27, 2001 at 16:21:37, Michel Langeveld wrote:
>On November 27, 2001 at 05:56:52, Tony Werten wrote:
>
>>On November 27, 2001 at 04:55:14, Tony Werten 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:
>>>>>
>[snipped a lot of nice words]
>
>Yes, this code is better yes. Also I like the idea of handling double pawns as
>passer candidates. But ofcourse this is just a sub optimal algoritm of
>evaluating pawns. For evaluation a real pawn structure evaluation also weak
>pawns must be considered. Weak pawns (In Dutch: zwakke pionnen) are pawns which
>can't be defended anymore by it's own pawns. There's also a term backward pawns
>(In Dutch: Achtergebleven pionnen). And not all backwards pawns are weak.
Of course you need to make the pawnstructure evaluation bigger. But passed pawns
are the best one to start with. Then double, triple, isolated, then the rest of
your engine, then backwards, then if there is nothing more to do passer
candidates.
>
>About the code:
>
>Isn't this the same and shorter (sorry if not I'm very tired now)?
>
This works if you set rank to zero if there is no black pawn. When no white pawn
it should be set to 7. ( and change <= to >=)
>if (whitepawn_rank[currentline] > blackpawnrank[current_line] &&
>(
> current_line = 0 ||
> blackpawn_rank[current_line-1]<whitepawn_rank[current_line])
>)
<=
>&&
>(
> current_line = 7 ||
> blackpawnrank[current_line+1]<whitepawn_rank[current_line])
>)
<=
>{
> //passer found
>}
>
>Now I think longer I think in this position
>[D] 7k/p1pp4/8/8/8/8/PPPP4/7K w - -
>
>White thinks that the A pawn is a passer. This is incorrect.
Should not happen.
if (whitepawn_rank[currentline] > blackpawnrank[current_line]
if 2>6 so the rest is not taken.
Tony
>
>>>AND
>>>(black does not have a pawn on current line OR *1
>>> blackpawn_rank[current_line] < whitepawn_rank[current_line]) *1
>>>AND
>>>(current_line=0 OR
>>> black does have pawn on [current_line-1] OR
>> ^^^
>>oops, not
>>> blackpawn_rank[current_line-1]<=whitepawn_rank[current_line])
>>>AND
>>>(current_line=7 OR
>>> black does have pawn on [current_line+1] OR
>> ^^^
>> not
>>
>>> blackpawn_rank[current_line+1]<=whitepawn_rank[current_line])
>
>regards
>
>Michel
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