Author: Robert Hyatt
Date: 19:26:53 09/18/05
Go up one level in this thread
On September 18, 2005 at 16:14:10, Uri Blass wrote: >On September 18, 2005 at 15:43:28, Chan Rasjid wrote: > >>On September 18, 2005 at 14:34:56, Uri Blass wrote: >> >>>On September 18, 2005 at 14:12:11, Chan Rasjid wrote: >>> >>>>This means there is NO-MATCH whatsoever with a 1 - 1000x nps difference. >>>>Fruit's seems to sacrifice complicated (undue) evaluation in favour of high nps >>>>and makes the top. >>> >>>I disagree >>> >>>Fruit has a very strong evaluation function. >> >>Firstly, I don't make definite statement but more of a guess, ie seems so to >>me..The one think I have not examined yet in details is Fruit's evaluation. >> >>For your info, I think you made the same observations that I just found and >>more of the secret of Fruit, ie data/structure organization, locality of >>data,etc. eg. After I got the hint, when in domove(), I make(myself) copies of >>board->sq[] for from, to, capture/ep with sqFrom, sqTo, sqCatureEP so that I >>don't have cache jumping back to access board->sq[256]. Then I found Fruit does >>the same. I believe the has an extra board->pos[256] for locality of data within >>cache. >> >> >>Strong evaluation may just mean good evaluation for:- >>1) most basic standard stuffs that definitely do not harm, but gainful >>2) b/r/ QUEEN mobility >>3) attack king / king safety. >> >>Some others have full eval()for every pins. Does Fruit do any pins ? >>If not then probably terms/factor wise, Fruit's evaluation is only professional >>basic. >> >>> >>>Most of the improvement from Fruit1.0 to Fruit2.1 is because of better >>>evaluation. >> >>Of course eval() pays when optimal but after it is near optimal IT CANNOT >>BE IMPROVED FURTHER. You can easily make it pays negative. >>So we cannot be sure the reason Fritz, shredder lost is NOT because they wasted >>critical time in pursuing complicated eval() that pays negative. >>> >> >>>Crafty is faster than Fruit in nodes per second so nodes per second is not the >>>secret of Fruit. >> >>By what factor , x 5 ? >> >>Ask Diepeeven. Crafty has a little evaluation (may be true comparatively ?) >>and on bitboard which is not the way YET(?). >> >>I would bet generally if Crafty is just nps 3 x , it will outdo Fruit, provided >>of course there are no major problems that the chess programming world is not >>aware yet. > >The difference between fruit and Crafty is more than 3:1 speed advantage. > Where are you getting your info? From games I have been playing against Fruit on ICC, it's NPS on the same procesor is faster than mine... Of course it is impossible to verify hardware online, but I can verify NPS since the thing kibitzes... >> >>> >>>Uri >> >>I did this experiment, something like this:- >> >> if (board->ply_nb <= 16)// dont eval if above ply 16 >> eval_piece(board,mat_info,pawn_info,&opening,&endgame);// mobility is here >> >> if (board->ply_nb <= 16)// dont eval if above ply 16 >> eval_king(board,mat_info,&opening,&endgame); >> >> //passers allowed >> eval_passer(board,pawn_info,&opening,&endgame); >> >> if (board->ply_nb <= 16)// dont eval if above ply 16 >> eval_pattern(board,&opening,&endgame);// very simple stuff >> >>Those are fruit's major eval(). >>It did not seem to weaken Fruit at all, wins ruffian,aristarch etc. >> >>Rasjid > >What time control did you use? >At fast time control you do not get 16 plies in most lines. > >Uri
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