Author: Dann Corbit
Date: 21:32:04 09/12/03
Go up one level in this thread
On September 12, 2003 at 21:39:10, scott farrell wrote: >On September 12, 2003 at 15:34:41, Dann Corbit wrote: > >>On September 12, 2003 at 15:23:02, Omid David Tabibi wrote: >> >>>On September 12, 2003 at 13:46:42, Dann Corbit wrote: >>> >>>>This has the source code, and Visual Studio.NET 2003 solution file: >>>>ftp://cap.connx.com/chess-engines/new-approach/CRAFTY_Mpc.ZIP >>> >>>Have you tried running it on some tactical test suits? >> >>Yes. It clearly hurts tactical performance at fast time control. > >(I got the ftp to work, windows couldnt do it, but wget on linux was fine) > >Is it just the section headed probcut? I see no comments for mpc or >multi-probe-cut. > >Can you give me a short English run down on what you are achieving? I read the >essay you pointed to as well. As far as I can work out the paper, and your code >does: >1. reduce depth searches as a proxy for deeper ones >2. uses a bound that is harder to prove/cut, but my C skills are not good enough >to fathom this: > bound = rint((pa->t * pa->s + beta - pa->b) / pa->a); >3. The depth reduction changes depending how deep you are in the tree >depth - (depth / INCPLY - pa->d) * INCPLY >4. is it recursive (it looks like it to me). > > >My implementation is different, so maybe its a different idea, multi-probe-cut. >This is roughly what I do: > >1.try null move first >2. try IID if no good move from hash >3. generate all moves, and order all moves >4. try MultiProbeCut which is: >4a. iterate first 6 moves from sorted list >4b. doMove >4c. search at beta, beta+1 (ZWS search at beta) at depth -2 >4d. undoMove >4e. if I get 2 fail-hi, then fail high >4f. if multiprobe fails, re-order moves with new knowledge >5. start iterating all moves, normal searching with PVS etc. > >I'd been interested if you think this is similar, I think its 2 different ideas >witha simlar name. I did not make the changes (except a few tweaks to make it run under Win32). All the crafty mods were by Mr Buro.
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.