Author: Robert Hyatt
Date: 09:19:19 05/02/01
Go up one level in this thread
On May 02, 2001 at 11:37:02, Paul wrote: >On May 02, 2001 at 11:21:48, Robert Hyatt wrote: > >>On May 02, 2001 at 10:08:09, JW de Kort wrote: >> >>>dear friends, >>> >>>A few weeks ago i posted a question about cutting my qsearch. With the valuable >>>information you send me i have been able to get a serious reduction for wich i >>>want to thank all to people who helped me realize this. >>> >>>Later i realizes that up till now i have not paid much attention to the move >>>order in the root. The program calculates all the moves and starts the iteration >>>at 1 ply in the order in which the moves are found. If i move is found to be >>>better than all the previous moves tried, this move is placed in front and all >>>the others are shifted one place lower in the order. This gives some kind of >>>ordering after a few iteration. >>> >>>I noticed that mr Hyatt uses a far more advanged methode of ordering but his >>>methode is not clear to me. >>> >>>Also i ask myself if it it worth the effort to try to do a good root move order. >>> >>> >>>I hope some one can help me >>> >>>Thanks in advance >>> >>>Jan Willem >> >> >>Mine is easy to do... and dates back to the early days of Cray Blitz, so it >>has been tested quite extensively... >> >>I save the nodes searched for each root move. For the PV move (the best move >>after iteration N) I set its node count to something larger than any other move, >>then I simply sort on node counts. This puts the PV from iteration N-1 first >>when we do iteration N. If you change your mind at N-1 once, then the original >>best move plus the new best move will have the two highest node counts and they >>will be first. Etc. >> >>Simple and effective. > >I also use nodecounts after reading about it on CCC. But what type do you use >for the counter, an unsigned int? That will overflow after a search of a couple >of hours on these 1M node/s machines we have nowadays, wouldn't it? Or am I >missing something (like a shift right)? > >Groetjes, >Paul I just use an unsigned int at present. 4 billion nodes on a single root move is a bunch of searching. Hopefully by the time it happens we will be on 64 bit processors and the problem won't exist.
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.