Author: stuart taylor
Date: 17:08:06 09/27/01
Go up one level in this thread
On September 27, 2001 at 18:03:43, Uri Blass wrote: >On September 27, 2001 at 17:45:03, Roy Eassa wrote: > >>On September 27, 2001 at 15:53:35, Uri Blass wrote: >> >>>On September 27, 2001 at 15:23:07, Roy Eassa wrote: >>> >>>>On September 27, 2001 at 14:52:46, Uri Blass wrote: >>>> >>>>>On September 27, 2001 at 14:14:07, K. Burcham wrote: >>>>> >>>>>>takes shredder5 51 seconds to decide on Qh1. 1500 mhz amd >>>>>> >>>>>>Engine: Shredder 5 >>>>>>by Stefan Meyer-Kahlen >>>>>> >>>>>> >>>>>> 1.00 0:27 +9.84 1.dxe4 Rxd5 2.Rxg4 Bxc3 (5.687.141) 205.4 >>>>>> 1.00 0:51 +M1++ 1.Qh1+ (10.192.541) 199.6 >>>>>> 1.00 0:51 +M1 1.Qh1+ (10.192.542) 199.6 >>>>>>best move: Qa1-h1 time: 0:51.058 min n/s: 199.642 nodes: 10.192.560 >>>>>> >>>>>>kburcham >>>>> >>>>>New position >>>>>[D]8/8/pppppppK/NBBR1NRp/nbbrqnrP/PPPPPPPk/8/Q7 w - - 0 1 >>>>> >>>>>Analysis by Goliath Light 1.5: >>>>> >>>>>1.Qh1# >>>>> +- (#101) Depth: 4/31 00:00:15 2874kN >>>>>1.Qh1# >>>>> +- (#1) Depth: 4/31 00:00:15 2874kN >>>>> >>>>>(Blass, Tel-aviv 27.09.2001) >>>>> >>>>>I do not understand the first mate in 101 score >>>>> >>>>>Deep Fritz's analysis after more than 10 minutes of search >>>>> >>>>>New position >>>>>8/8/pppppppK/NBBR1NRp/nbbrqnrP/PPPPPPPk/8/Q7 w - - 0 1 >>>>> >>>>>Analysis by Deep Fritz: >>>>> >>>>>1.dxe4! >>>>> +- (1.56) Depth: 1/2 00:00:00 >>>>> >>>> >>>> >>>>Is there a simple, understandable reason why several "strong" programs take so >>>>long here? (Deep Fritz not seeing the mate in 1 after 10 minutes is >>>>mind-boggling to me!) >>> >>>Yes >>> >>>Deep Fritz probably does a typical computer mistake >>>of searching all the captures first. >>> >>>My guess is that one of the possible lines that >>>Deep fritz searches is for example: >>> >>>1.dxe4 gxf5 2.Rxg4 fxg4 3.Bxd4 Bxa5 4.exf4 cxb5 5.Rxh5 Bxb3 >>>6.fxg4 Kxg4 7.Bxf6 Kxg3 >>> >>>I guess that it is only one of the lines that Deep Fritz see >>>before looking at Qh1# >>> >> >> >>I thought all programs searched everthing one ply first, then two ply, then >>three, etc. If there's a MATE at one ply, then it would find it in a tiny >>fraction of a second, no matter which order it chose to look at the moves, no? >>Or is it doing extensions on other moves, even at ply 1? > >yes >it does a lot of extensions in this kind of positions. >it extend all the logical captures. >usually the number of captures is not big so it can finish the job very fast but >it is not the case in the relevant position. > >Uri When my old Turbo King (of about 1989) was in working order, I tried all kinds of wierd positions, and there was never a mate in two, however complex which needed as much as 2 seconds to solve. Mates came quicker than the search of the complete ply, in many cases. Can anyone with that machine, test it? Or another old machine? I might get mine back into use one day, but only when I have time to look for it etc. S.Taylor
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.