Author: Stan Arts
Date: 00:53:57 12/03/03
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Hi If you do a nullmove after Qg6 , that means you do a nullmove on the 2nd ply in the search tree allready. Although this seems to give better node-counts, it also gives a lot of problems when I try it in my program. (Missing simple tactics, as you describe) So, in Neurosis I don't use null-move on the first 2 ply. I think this will possibly fix your problem. Greetings and goodluck, Stan Legal moves: 59 Ply Score Time Nodes Best move and expected line ------------------------------------------------------------ 2 -229 5 1039 Nxc6 Qxc6 3 -229 5 1422 Nxc6 Qxc6 Ng4 3 9995 16 7852 Qg6 <M3> < + > Bf5 Qh7+ 3 9997 16 8119 Qg6 <M2> Bf5 Nxf7+ 4 9997 22 12867 Qg6 <M2> Bf5 Nxf7+ 5 9997 44 24910 Qg6 <M2> Bf5 Nxf7+ 6 9997 99 48492 Qg6 <M2> Bf5 Nxf7+ Total nodes:77131 n/sec:45371 (Q-nodes:14297 max depth:11) On December 02, 2003 at 18:32:08, macaroni wrote: >this is the analasys from the re-write of my engine from the first position in >WAC. >[D]2rr3k/pp3pp1/1nnqbN1p/3pN3/2pP4/2P3Q1/PPB4P/R4RK1 w - - 0 1 >-->"WAC001", best=Qg6 >stage=middlegame, playing as WHITE, nullmove is ON, Using >ply=1, value=-200, nodes=113, kNps=0, best=Ne5xc6 >ply=2, value=-200, nodes=2546, kNps=11, best=Ne5xc6 >ply=3, value=-200, nodes=7708, kNps=18, best=Ne5xc6 >ply=4, value=10000, nodes=129225, kNps=88, best=Qg3-g6 >ply=5, value=100, nodes=224379, kNps=105, best=Nf6-e8 >ply=6, value=10000, nodes=658686, kNps=125, best=Qg3-g6 >ply=6, value=10000, nodes=1012767, kNps=129, best=Qg3-g6 > >it's a very easy mate in 2, and the computer, as expected, finds it at ply 4, >but then disregards it at ply 5, for Ne8, which also just about wins. It is >nullmoving that has caused this, is there any way I can avoid this sort of >problem? it arises, because after playing Qg6, it nullmoves, and calls a 1 ply, >or 0 ply search, in both of these searches, black is better by 200 points, it >doesn't fail in the ply 4 search because there is nothing better, it DOES fail >in the ply 5 search because Ne8 is also good, so beta is 100, not -200. >cheers >tor
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