Author: Ross Boyd
Date: 01:56:05 09/02/04
Go up one level in this thread
On September 01, 2004 at 19:56:30, GeoffW wrote: >On September 01, 2004 at 18:20:20, Robert Hyatt wrote: > >>On September 01, 2004 at 00:51:47, Stuart Cracraft wrote: >> >>>I know this is a long shot throwing this out there without much more >>>info, but perhaps I'll get lucky and someone has seen this before. >>>It's appeared on this bulletin board about 6 years ago. >>> >>>[D]4r1k1/p1qr1p2/2pb1Bp1/1p5p/3P1n1R/1B3P2/PP3PK1/2Q4R w - - bm Qxf4; id >>>"WAC.141"; >>> > >This was an interesting post as I have just been adding mate threat extensions >to my program and fixing a bug or several at the same time. > >One of the things I noticed that was a little puzzling was the +2 > >if (value == -MATE + ply + 2) > mate_threat = 1; > >For my program it needs to be +1 to make this work correctly. I discussed this >with Ross (Trace) and it was +1 for him too, yet for Stuart and Crafty that >needs to be +2, still havent explained that one ? > Hi Geoff, I think one possibility is this... I don't increment 'ply' when null-moving... (i decrement remaining depth, of course) That may explain why Crafty works with +1 and TRACE works with +2. In fact, that may point out a capital search bug in TRACE. My nullmoves 'corrupt' the true value of ply. Not good. And it explains some odd search behaviours. Also, I cannot test if (ply & 1) to see if the side to move is a particular colour. I will fix this in the next week or so and see if it helps. Oooooohhh.... I have a good feeling about this... Ross
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.