Author: scott farrell
Date: 23:48:29 11/29/02
Go up one level in this thread
On November 30, 2002 at 01:37:01, Uri Blass wrote: >On November 29, 2002 at 22:34:40, scott farrell wrote: > >>On November 29, 2002 at 21:12:55, Scott Gasch wrote: >> >>>On November 29, 2002 at 17:22:20, Will Singleton wrote: >>> >>>>2rr3k/1p4p1/1P2b2p/p1Bnpp1q/8/Q1P2PP1/P6P/RB3RK1 b - - 0 26 >>>> >>>>Solution times (amd 1.6ghz): >>>> >>>>Yace not in 5 min >>>>Crafty not in 5 min >>>>Aristarch 3:48 min >>>>Gromit 3:12 min >>>>Ruffian 44 sec >>>>CM9000 5 sec >>>> >>> >>>Monsoon fails high in 2:16 and resolves a PV in 4:27. >>> >>> 1u +0.35 00:00:00.02 11 PV= a4 <+0.00> >>> 1u +1.35 00:00:00.05 57 PV= Nf4 <+0.00> >>> 1. +1.35 00:00:00.08 77 PV= Nf4 <+0.00> >>> 2- +0.57 00:00:00.13 190 **FL** -- >>> 2u -0.47 00:00:00.14 302 PV= Ra8 1. Bd3 <+0.00> >>> 2u -0.36 00:00:00.15 380 PV= Rc6 1. Qxa5 <-1.00> >>> 2u -0.10 00:00:00.16 448 PV= Nf6 1. Qxa5 <-1.00> >>> 2. -0.10 00:00:00.21 508 PV= Nf6 1. Qxa5 <-1.00> >>> 3. +0.59 00:00:00.27 1635 PV= Nf6 1. Qxa5 e4 <-1.00> >>> 4u +0.64 00:00:00.31 6748 PV= Rc6 1. Bd3 Nxb6 2. Bxb6 Rxb6 [Q] >>> > 3. Qxa5 [Q] <+0.00> >>> 4. +0.64 00:00:00.38 9055 PV= Rc6 1. Bd3 Nxb6 2. Bxb6 Rxb6 [Q] >>> > 3. Qxa5 [Q] <+0.00> >>> 5+ +1.40 00:00:00.47 22433 Nf6! ++ >>> 5. +1.49 00:00:00.63 42341 PV= Nf6 1. Bd6 Bc4 2. Re1 Qxf3 3. Bxe5 >>> > [Q] <+0.00> >>> 6. +1.52 00:00:00.93 90963 PV= Nf6 1. Bd6 e4 2. fxe4 fxe4 3. Bc2 >>> > <+0.00> >>> 7. +1.77 00:00:01.49 209895 PV= Nf6 1. Bc2 Rd2 2. Rf2 Rxf2 3. Bxf2 >>> > Qxf3 4. Qxa5 [Q] <+0.00> >>> 8. +1.77 00:00:03.82 698640 PV= Nf6 1. Bc2 Rd2 2. Rf2 Rxf2 3. Bxf2 >>> > Qxf3 4. Qxa5 <+0.00> >>> 9+ +2.52 00:00:05.36 994464 Nf6! ++ >>> 9. +2.71 00:00:08.69 1812429 PV= Nf6 1. Bd6 Bc4 2. Rf2 e4 3. g4 Nxg4 >>> > 4. fxg4 Qxg4+ [+] 5. Bg3 Rd1+ >>> > [Q] 6. Kg2 [Q] <-1.00> >>>10. +3.02 00:00:26.78 5824368 PV= Nf6 1. Bd6 Bc4 2. Rf2 e4 3. Bc2 >>> > e3 4. Rg2 Qxf3 5. Re1 <+1.00> >>>11+ +3.77 00:02:16.62 28726569 Nf4! ++ >>>11. +5.19 00:04:27.40 58248289 PV= Nf4 1. gxf4 Rd2 2. Bf2 [threat] >>> > Qxf3 3. Qxa5 Bd5 4. Qxd5 [threat] >>> > Qxd5 5. Bxf5 Rf8 6. c4 Qxc4 [Q] >>> > <+3.00> >> >>How do you guys get this sort of output? > >I also do not understand it. > >Monson finished depth 10 with Nf6 in the pv but I do not see pv for Nf6 at depth >11. > I think they must be doing something like, start depth 11 with a window of say 3.5 to 3.6. This "fails-high" where any one branch can prove it can do atleast as good at 3.6 using soft alpha/better bound, or they actually used say 3.5-3.77. Assuming that fail-low are real fast, and the search ussually fails low, then they ussually dont waste much time. I report fail-low at the root, to see this sort of this, using -INFINITY to INFINITY, you dont get fail low at the root. So after the fail-high, they know atleast one move is dramatically better, but not exatly how much better, or if there is also another real good move which is better. When they re-search, they search with say 3.77-INFINITY. My hashtable/hash alorithm doesn't have data/smarts to do window searches like this. What extra info do I need, I current store the type of bound (a/b/exact), and the score, and do Robert H's fail low/fail hi routine if enough depth. >Does it start analyzing Nf4 and not Nf6 at depth 11? >> >>My engine doesnt report the final move Nf4 until it has fully analysed that >>move, and hence already has the PV. > >I do not understand. > >Do you use normal alpha beta? > >I try to find if other moves are better than the best move that I found. >For that purpose I use a window of 0.01 pawns. > >If they are better I have a fail high and increase the size of the window from >0.01 pawns to something bigger than 0.01 pawns. > We are saying the same thing, I use PVS, but have to have fully searched a move at each ply first. They did something smarter than us. Or are you saying 0.01 pawns from previous iteration, say from ply 10 in this example. >Uri
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