Author: Andreas Herrmann
Date: 17:13:11 09/09/03
Go up one level in this thread
On September 09, 2003 at 17:20:52, Jose Santos wrote: >Hi again, > >>So, are you saying that a pure minmax search delivers the same values ? > >Yes, that's what I'm saying and I'm pretty sure about it (unfortunately). > >>How about the node counts in either case ? > >What do you mean by this ? how many nodes I search for each move ? >Here is it at ply 4 (first is the move, second is the score, third is the number >of boards analyzed to determine it, without alpha-beta cuts). > >G1-F3 -220 9754 >G1-H3 -220 8883 >B1-A3 -220 8885 >B1-C3 -184 9757 >H2-H3 -184 8457 >H2-H4 -184 9329 >G2-G3 -184 9347 >G2-G4 -184 9328 >F2-F3 -184 8457 >F2-F4 -184 8929 >E2-E3 -184 13280 >E2-E4 0 13308 >D2-D3 0 11961 >D2-D4 0 12437 >C2-C3 0 9347 >C2-C4 0 9818 >B2-B3 0 9347 >B2-B4 0 9332 >A2-A3 0 8457 >A2-A4 0 9329 > >>That's hard to believe for me. IMHO, grouping the scores like in your case >>above, looks to me very much like a consequence of alpha-beta. > >Yes, I know. I also couldn't believe on it, that's why I made this post. > >>If in your case, alpha-beta and minmax-pure deliver the same set of scores on >>the root level, then something is definitely going wrong. > >Yes... but it doesn't play stupidly bad (altought it's not very good either). If >you are curious you can download latest version here: >http://ctp.di.fct.unl.pt/~jcas/chess/chesswin32.exe >I've also done a Linux version: >http://ctp.di.fct.unl.pt/~jcas/chess/chesslinux.exe >Win32 version is more recent. Both are just console for now, I've done a GUI >yet. > >Regards, > > Jose Santos Hi Jose, welcome to the chess programmer community. I have just added your download links to my new link page for Pascal/Delphi chess programmers http://wbholmes.de/links_pascal.htm. I hope your links are not temporary. To your problem: Perhaps an error in your AlphaBeta algorythm. You should post a part of it here for a better help. Andreas
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.