Piece square tables

[Rafael Peña]

Geschrieben von: / Posted by: Rafael Peña at 20 February 2004 00:14:46:

Hi
please, where can i find a good "piece square tables" for add them to my chess engine.
thanks.

[Dann Corbit]

Geschrieben von: / Posted by: Dann Corbit at 20 February 2004 00:30:02:
Als Antwort auf: / In reply to: Piece square tables geschrieben von: / posted by: Rafael Peña at 20 February 2004 00:14:46:

Hi
please, where can i find a good "piece square tables" for add them to my chess engine.

Most people rip them out of TSCP.
However, you might do better by reasoning from first principles.
For instance, take a chessman of any sort, and put it on each square of the board. See how many squares it attacks. That will show you right away that a knight is worst in a corner (for example). The king will look very strong in the center, but it is only a good idea for the endgame. It will also show you that the a and h pawns are weaklings (so much so that it is sometimes worthwhile to double a pawn on the b or g rank in order to get the weak a and h pawns some more force).
Add to these numbers a bonus for:
1. Being past the centerline towards the enemy camp
2. Being close to the enemy king
Probably, you will have more fun working out the numbers for yourself than just using them from someone else.
I have found that my numbers are not like those of other people. But they are similar enough to make good moves.



my ftp site {remove http:// unless you like error messages}

[Tord Romstad]

Geschrieben von: / Posted by: Tord Romstad at 20 February 2004 07:37:44:
Als Antwort auf: / In reply to: Re: Piece square tables geschrieben von: / posted by: Dann Corbit at 20 February 2004 00:30:02:

Probably, you will have more fun working out the numbers for yourself than just
using them from someone else.

Not only will you have more fun this way, I also think you will end up with
better tables. Unless your eval contains nothing except material and piece
square tables, I think it is unlikely that tables taken from another program
will work well in yours. Which numbers work best depends to a great extent
on the rest of your evaluation function. For instance, if you have a good
pawn centre eval which can return big values, you probably don't want to have
very big bonuses for pawns occupying central square in the piece square tables.
But if you don't evaluate the pawn centre at all elsewhere in your eval, the
piece square table should probably have big values for pawns on central squares.
You will probably also find that the numbers which work well in the early
phases of development needs to be adjusted when your evaluation function
grows bigger and better.
Tord

[Uri Blass]

Geschrieben von: / Posted by: Uri Blass at 20 February 2004 09:52:33:
Als Antwort auf: / In reply to: Re: Piece square tables geschrieben von: / posted by: Dann Corbit at 20 February 2004 00:30:02:

Hi
please, where can i find a good "piece square tables" for add them to my chess engine.

Most people rip them out of TSCP.

I do not know what most people do.
I never took them from tscp and I do not think that you know what most people do.
Uri

[Uri Blass]

Geschrieben von: / Posted by: Uri Blass at 20 February 2004 09:59:01:
Als Antwort auf: / In reply to: Re: Piece square tables geschrieben von: / posted by: Tord Romstad at 20 February 2004 07:37:44:

Probably, you will have more fun working out the numbers for yourself than just
using them from someone else.

Not only will you have more fun this way, I also think you will end up with
better tables. Unless your eval contains nothing except material and piece
square tables, I think it is unlikely that tables taken from another program
will work well in yours.

I think that it is unlikely that somebody who asks that question have evaluation (maybe except material).
I started with only a move generator and my first evaluation had only piece square tables.

Uri

[Dann Corbit]

Geschrieben von: / Posted by: Dann Corbit at 20 February 2004 10:01:27:
Als Antwort auf: / In reply to: Re: Piece square tables geschrieben von: / posted by: Uri Blass at 20 February 2004 09:52:33:

Hi
please, where can i find a good "piece square tables" for add them to my chess engine.

Most people rip them out of TSCP.

I do not know what most people do.
I never took them from tscp and I do not think that you know what most people do.

Perhaps I was being a bit facetious.
But I can tell you that it is done a lot.



my ftp site

[Uri Blass]

Geschrieben von: / Posted by: Uri Blass at 20 February 2004 11:08:00:
Als Antwort auf: / In reply to: Re: Piece square tables geschrieben von: / posted by: Dann Corbit at 20 February 2004 10:01:27:

Hi
please, where can i find a good "piece square tables" for add them to my chess engine.

Most people rip them out of TSCP.

I do not know what most people do.
I never took them from tscp and I do not think that you know what most people do.

Perhaps I was being a bit facetious.
But I can tell you that it is done a lot.

I hope that you are wrong but unfortunately you may be right and it is possible that most of the programs are tscp clones or crafty clones or arasan clones or clones of other programs with public source.
Having evaluation tables that are exactly the same as another program suggest that the program is a clone of the second program.
I simply do not think that somebody knows the best tables so the right way to learn from other tables is to understand the idea behind the tables and to generate tables with your numbers and you can be practically sure that you will not get the same numbers as another program.
Uri