Author: Vincent Diepeveen
Date: 08:39:27 01/03/02
Go up one level in this thread
On January 03, 2002 at 11:14:33, Uri Blass wrote: >This is analysis of Crafty under chessbase GUI > >New position >[D]2r1k1r1/2p2pP1/1p5p/p3nP2/3N3B/P1P5/2q3PP/R3R1K1 b - - 0 1 > >Analysis by Crafty 18.12: > >4...Qxc3 5.Rxe5+ > -+ (-2.05) Depth: 1/6 00:00:00 >4...Qxc3 5.Rxe5+ Kd7 6.Re7+ Kd6 > ยต (-1.16) Depth: 2/6 00:00:00 > >I am interested to know what is the remaining depth of Crafty after >every move at depth 2. > >I think that the only relevant extensions of Crafty for the pv is check >extension and one reply to check extension(mate threat is not relevant at depth >2,recapture is not at the same square and no pawn is pushed) > >Does it mean the following? > >1)The remaining depth after 4...Qxc3 is 1 because Qxc3 reduce 1 from the >remaining depth correct. >2)The remaining depth after 5.Rxe5+ is 2 because after this move crafty extends >for 2 reasons(check and single reply) so it add 2 to the remaining depth thanks >toextension and reduce only 1 from the remaining depth as usual. not exactly. cheaper is extending check evasions. So only after Re5 then a move from black triggers extension, not the checking move itself. >3)The remaining depth after 5...Kd7 is 1 right and then check gets detected and the thing extends with 1 ply usually. So then after kd7 the depth is again 1 ply. >4)the remaining depth after 6.Re7+ is again 1(check extension) remaining depth after re7 is 0. Bob is in better position to answer what he does when depth is 0. whether he still extends this or directly triggers qsearch. Older versions directly triggered Qsearch. that's cheapest. Being in check or not, or mated. It doesn't matter for crafty in qsearch. >5)the remaining depth after 6...Kd6 is 0 >6)Crafty has to evaluate and find no good capture for white so the pv ends at >this point >Uri
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.