Author: Uri Blass
Date: 05:07:02 12/17/02
Go up one level in this thread
On December 17, 2002 at 07:59:21, JW de Kort wrote: >On December 17, 2002 at 07:53:15, Uri Blass wrote: > >>On December 17, 2002 at 07:30:02, JW de Kort wrote: >> >>>On December 17, 2002 at 07:07:46, Uri Blass wrote: >>> >>>>On December 17, 2002 at 06:31:50, JW de Kort wrote: >>>> >>>>>On December 17, 2002 at 05:45:28, Uri Blass wrote: >>>>> >>>>>>On December 17, 2002 at 05:34:31, JW de Kort wrote: >>>>>> >>>>>>>On December 17, 2002 at 05:09:31, Gian-Carlo Pascutto wrote: >>>>>>> >>>>>>>>On December 17, 2002 at 04:15:26, JW de Kort wrote: >>>>>>>> >>>>>>>>>Hi, >>>>>>>>> >>>>>>>>>Currently i'am using a piecelist to keep track of the locations of the pieces in >>>>>>>>>my 0x88 based program. Iám thinking about removing this list and replacing it by >>>>>>>>>a bitboard to keep track of the piecelocations of white pieces and black pieces. >>>>>>>>>I'am wondering of anybody else does this (i think some one will) and if this is >>>>>>>>>a good improvement to spees up my engine which is terrably slow. I have good >>>>>>>>>expierences with other bitboards in my program. I already use bitboard to do the >>>>>>>>>pawn evaluations and i'am thinkin about gradually removing the 0x88 stuff to >>>>>>>>>replace it with bitboards >>>>>>>>> >>>>>>>>>any help appreciated >>>>>>>> >>>>>>>>Have you used a profiler to check where the program is spending most of its >>>>>>>>time? >>>>>>>> >>>>>>>>-- >>>>>>>>GCP >>>>>>> >>>>>>>Indeed i did. Most of its time is pend in the evualation code but that is nomal. >>>>>> >>>>>>I do not think that this is normal >>>>>>Amir ban said that only 20% of the time is spent on the evaluation code of >>>>>>Junior. >>>>>> >>>>>>The question is also what you define as evaluation code. >>>>>> >>>>>>I have arrays that are used in the evaluation and I update them when I make >>>>>>moves. >>>>>> >>>>>>Should I include the time that I update the array as part of my evaluation code. >>>>>>even if the arrays are used not only for evaluation but also for extension >>>>>>rules? >>>>>> >>>>>>Uri >>>>> >>>>>Dear Uri, >>>>> >>>>>I do not dream of comparing my program to Junior. I managed to cut the time >>>>>spend evaluating by using lazy evaluation. No my program does not do a full >>>>>evaluation in a large number of positions. >>>>> >>>>>If i would do what you did i would not include the time spend updating as part >>>>>of the time spend evaluating. >>>>> >>>>>Regards >>>>> >>>>>JWK >>>> >>>>By that definition today I use less than 5% of the time in evaluation. >>>>My evaluation includes only the following factors: >>>>1)piece square table >>>>2)mobility when I use only the number of moves that both sides have(this >>>>evaluation can be improved but it clearly help my program and I believe that it >>>>is more important than knowledge about pawn structure). >>>>3)double pawns(I use special arrays that are updated during making move for it) >>>>4)some secret factor that is easy to evaluate for my program. >>> >>>I have no exact percentage but i estimate about 50% is spend evaluating. I use >>>1) also, 2) i do not because i am afraid it is to costly to calculate but i will >>>try it soon, 3( i also have plus a number of other pawn factors, en 4) i also >>>have some extra features like devolpment etc. >>> >>> >>> >>> >>> >>> >>>> >>>>I believe that secret 4 is something that no program or almost no program knows >>>>to evaluate and I do not want to lose my relative advantage. >>> >>>You are right about this. >>> >>> >>> >>> >>> >>> >>> >>> >>>> >>>>I have also secrets in my search algorithm but at the same time I also do stupid >>>>things that no top program does(for example I do not use hash table efficientely >>>>and I do not have some productive extensions that crafty have) so my search is >>>>still clearly inferior to the search of the top programs. >>>> >>> >>>The same goes for my program. My hashtable is not used efficiently but iam happy >>>that is does work at all. >>> >>> >>> >>> >>> >>> >>>>My program can often beat crafty in tactics but I am not going to say that >>>>it is better than crafty in tactics inspite of the fact that it may be better >>>>than crafty in the GCP test suite(comparison in the gcp test suite is unfair >>>>because movei trains on this suite and I decided about changes in my search >>>>algorithm in some cases from learning the reason that movei failed). >>> >>>I have not jet matches up my program agains Crafty. >> >>I also do not play games with it against crafty and I meant to say that it often >>is better than crafty in test positions. > >Sorry, i miss understood, but never the less it is a good result that i hope to >achieve also one day. Why don't you play Crafty? > > >BTW"Is your engine available to the public? It would be nice to test my engine >against. The latest version is not available but old movei is available and is clearly better than tscp and probably slightly better than gerbil so you can use it for testing. > > > > > > > > >> >>> >>> >>> >>> >>> >>> >>> >>>> >>>>My target is of course to do it playing better but if I have some trick to make >>>>it clearly faster in some positions without making it slower in other positions >>>>then this trick is probably productive trick also in games(I also test in games >>>>to verify that I did not do something bad in my search rules). >>> >>>Can you be more specific? >> >>I can give one example >> >>I have an array that tell me if a piece is pinned(I use that array in my move >>generator that generates only legal moves) so there is no problem for me to >>check if the queen of the side to move is pinned. > >I'am thinking about implementing something like that but in 0x88 i think it is >very difficult. Do you use 0x88 or bitboards? I do not use bitboards but I also do not use 0x88. I use array of 64 squares. a1 is 0 and h8 is 63. For every square I use a 32 bit number to store information about the directions that a square is attacked in my attack tables(16 for white and 16 for black). Uri
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