Winboard Forum

hi,
experimental scorpio version can be downloaded from links below.
i am not sure of engine strength. I have worked very little on the engine so there will only be an elo drop if any. My main aim is to test egbbs.
4 pieces egbb are available. The 5 pieces are 1.6GB in size, if any one
is interested in hosting some of those i will be glad to send them.

http://www.geocities.com/dshawul/scorpio.zip
http://www.geocities.com/dshawul/book.zip
http://www.geocities.com/dshawul/egbb.zip

regards
daniel

Hi Daniel,

Let me check my understanding of egbb if I may.

It is my understanding that egbb is an alternative to egtb by Eugene Nalimov. You have made egbb freely available to other engines, and there are other engines that use them. Do you recall which engines they are?

What, if any, are the advantages of egbb compared to egtb?

-Norm

A tablebase file like Nalimov or Edwards format contains more information.

An EGBB file contains only the game state (won/lost/drawn/broken).

Because the files are smaller, they can often fit entirely into memory. For that reason, they are much faster to access. I have never seen an experiment that indicates regular tablebase files increase the strength of chess engines. It appears that the cost of the lookup is about the same as the value of the information received.

EGBB files, on the other hand, do seem to cause an increase in strength because the lookups are so fast.

I consider to change movei to use the egbb files.

My question is how do I use them.

Unfortunately I could not get them
and read that the page is currently unavailable for viewing.

I remember that I downloaded previous version of scorpio and there were some dll files but I also remember that I read later that probing positions that are not in the tablebases could give wrong draw results.

I also did not see step by step instructions how to use the files(what files to add to my project and what function to use to probe specific tablebase positions).

Uri

Hi Daniel,

"The 5 pieces are 1.6GB in size, if any one
is interested in hosting some of those i will be glad to send them."

You could upload them till 100Mb each file (even splitted files are allowed) to www.r a p i d share.de. It's a free service. To let people know about the possibility of download you can give the list of uploaded files to the forum.

The omissions in the word "rapid" in telling the right url I don't understand. Volker, where is the problem?

Best regards

Hartmut

Do you recall which engines they are?

I have seen the following engines:

- Gambit Fruit
- Latista
- DanaSah
- Atak

I read later that probing positions that are not in the tablebases could give wrong draw results

I have post in the forum a position where it happened me, Daniel seems that it corrected, the one made a new version of the dll.

After hundred of games, I am unable to reach a conclusion with the bitbases, if it plays better or worse. If that I can say that the best test of 100 games was in an occasion with the active egbb. My engine can vary so much in 100 games that it is difficult the conclusions.

I intent to consent to the egbb when the phase of the game is the endgame, so it doesn't affect to the rest of the game.

I am wanting to prove the new bitbases.

Hi all

What, if any, are the advantages of egbb compared to egtb?

They are fast to access. This is only true for the 4 piece tables. All 5 pieces will not fit in to memory. I will be providing an option to pre load
krpkp of kppkp in to ram if necessary. IMO I think that a general lru cache is not as bad as i thought it would be, so there may not be any performance gain on 5 men.
Another advantage is they are small. Mine are not so far very well compressed but i know that Vincent's are *far* smaller than Nalimov's.

I consider to change movei to use the egbb files.
My question is how do I use them.

Uri,thanks for your interest. The earlier bitbases and modified tscp code can be downloaded here.
http://www.geocities.com/dshawul/tscpegbb.zip
http://www.geocities.com/dshawul/egbbdll.dll
This are only for 4 men. The changes in tscp are in eval.c main.c and protos.h. Or you might want to wait until i am done with the 5 pieces which i will provide documentaiton for.

You could upload them till 100Mb each file (even splitted files are allowed) to www.r a p i d share.de. It's a free service. To let people know about the possibility of download you can give the list of uploaded files to the forum.

Thanks for the information. I will try that when i am finished compressing them down to 500/600mb.

I intent to consent to the egbb when the phase of the game is the endgame, so it doesn't affect to the rest of the game.
I am wanting to prove the new bitbases.

Pedro, you shouldnt probe bitbases when there are more than 5 pieces.
You have to keep track of the number of pieces on board all the time and probe only when it is below 5.

regards
Daniel[/quote]

Hello Daniel,

I cannot access your seite since 24 hours. It is permanently
temporarily unavailable
I need to know if you have updated the book?

Guenther

Hi Gunther
I have used more than allowable disk space and
transfer rate,thats why it is "temporarily" unavailable
Yes the book is updated. I will send it by mail.
Daniel

Hello Daniel
I had been unable to make Experimental Scorpio to load 4 pieces egbb tables of Scorpio 1.6. I tried putting them in same folder or using a path.
Also it had been impossible to download the updated book from geocities site.
Please your help.
Pablo

Daniel Shawul wrote:hi,
experimental scorpio version can be downloaded from links below.
i am not sure of engine strength. I have worked very little on the engine so there will only be an elo drop if any. My main aim is to test egbbs.
4 pieces egbb are available. The 5 pieces are 1.6GB in size, if any one
is interested in hosting some of those i will be glad to send them.

http://www.geocities.com/dshawul/scorpio.zip
http://www.geocities.com/dshawul/book.zip
http://www.geocities.com/dshawul/egbb.zip

regards
daniel

I understood that probe_egtb is a function but
I did not understand initially what is the meaning of PPROBE_EGBB

I saw that it is type def and I understand that
typedef declarations do not introduce new types but only introduce new names for existing types.


If I understand correctly then every time when we see

PPROBE_EGBB x

we can replace it by
int (*x)(int player,int w_king,int b_king,
int piece1,int square1,int piece2,int square2);

I understand that we can replace by something else also the line

probe_egbb = (PPROBE_EGBB) GetProcAddress(hmod,"probe_egbb");

I guess that it is by

probe_egbb=((int*)(int player,int w_king,int b_king,int piece1,int square1,int piece2,int square2)) GetProcAddress(hmod,"probe_egbb");

Do I understand correctly?

I am not experienced in using dll files and
I want to understand the code before using it and when I am not sure if I understand correctly I prefer to ask before I continue.

Uri

Hi all

Uri,
you are right PPROBE_EGBB is a pointer to the probe function.
Parameters:
Squares and type of piece , upto 5 pieces.
Return:
an approximate score for the current position.
I use material values 100 350 350 500 975 , and other bonuses are added depending on square of king. So if the score > 0 it is a win , < 0 is a loss 0 = draw, _NOTFOUND is bitbase is not found.

Pablo,
By default,It should work if you put the egbb folder in the same directory as the exe.I will send you the whole file by email.

regards
daniel

[quote="Daniel Shawul"]Hi all

Uri,
you are right PPROBE_EGBB is a pointer to the probe function.
Parameters:
Squares and type of piece , upto 5 pieces.
Return:
an approximate score for the current position.
I use material values 100 350 350 500 975 , and other bonuses are added depending on square of king. So if the score > 0 it is a win , < 0 is a loss 0 = draw, _NOTFOUND is bitbase is not found.

Pablo,
By default,It should work if you put the egbb folder in the same directory as the exe.I will send you the whole file by email.

Daniel
At last at 5:00 AM local time I was able to download from geocities your book and egbb files.
I put the egbb folder in same directory of Scorpio and it load all 4 pieces egbb files.
But when I try to play with Scorpio at Winboard, the engine did not start announcing "egbb\kqqqk.w.cmp not found" ???

I attach herein the winboard.debug file:
"recognized 'normal' (-1) as variant normal
WinBoard 4.2.7 + ScorpioExp
Reset(1, 0) from gameMode 0
recognized 'normal' (-1) as variant normal
GameEnds(0, (null), 2)
StartChildProcess (dir="c:\Wbrd\P-Sk\ScorpioExp") ScorpioExp
1480 >first : xboard
protover 2
1590 <first :
1590 <first : ht 1048576
1590 <first : pht 262144
1590 <first : eht 131072
1590 <first : EgbbProbe 1.0 by Daniel Shawul
1590 <first : Cache Size = 4 Mb (511 entries)
3290 <first : egbb\kqqqk.w.cmp not found
Fatal Error: Failed to start first chess program ScorpioExp on localhost: egbb\kqqqk.w.cmp not found

11530 >first : new
random
11530 >first : level 40 10 0
11530 >first : post
11530 >first : hard
11530 >first : easy
GameEnds(0, (null), 2)
41850 >first : force
41850 >first : quit"

Please your comments,
Pablo

Unfortunately I have no luck in downloading the bitbases.

I remember that I downloaded some bitbases earlier but they did not include all the 4 piece bitbases.

I think to use the bitbases for 4 pieces and nalimov tablebases for 5 pieces but I decided not to start to code it before getting the relevant bitbases.

Uri

I put copies here:
http://cap.connx.com/chess-engines/new- ... h/egbb.zip
http://cap.connx.com/chess-engines/new- ... h/book.zip
http://cap.connx.com/chess-engines/new- ... corpio.zip

My site is also cantankerous, but maybe people can get access to it when they cannot get to D.S.'s site

Hello Daniel,

I have a question regarding the new egbb.
Are those currently only for being used with Scorpio or
can they be used immediately by all other programs,
which support your bitbases too?
I am asking because the new ones have a different format
and I am not sure the supporting programs have to adapt
some changes in their programs?

Best regards,
Guenther

P.S. Thanks for sending the new book via mail

Hi Gunther
Dont start using the new bitbases now.
The dll is only a beta to test some things. I have already finished backward compatibility for those who already supported them. So all of the engines who have supported the old ones
will work with the new ones. If you are interested i can send you the new
egbbdll that works with all. A few test matches between my favourite engines scorpio,gfruit,latista,Dansah? :)
daniel

Daniel Shawul wrote:Hi Gunther
Dont start using the new bitbases now.
The dll is only a beta to test some things. I have already finished backward compatibility for those who already supported them. So all of the engines who have supported the old ones
will work with the new ones. If you are interested i can send you the new
egbbdll that works with all. A few test matches between my favourite engines scorpio,gfruit,latista,Dansah? :)
daniel

Daniel,
Please send me too the egbdll that works with all and tell also where to put it.
Many thanks,
Pablo

<Daniel wrote:>

Hi Gunther
Dont start using the new bitbases now.
The dll is only a beta to test some things. I have already finished backward compatibility for those who already supported them. So all of the engines who have supported the old ones
will work with the new ones. If you are interested i can send you the new
egbbdll that works with all. A few test matches between my favourite engines scorpio,gfruit,latista,Dansah? SmileSmile
daniel

Well, perhaps at the weekend, if you send it to me
BTW the error described by Pablo above (missing file in egbb) is fixed?

Best wishes,
Guenther