Author: Robert Hyatt
Date: 05:45:12 09/08/02
Go up one level in this thread
On September 07, 2002 at 23:44:37, scott farrell wrote: >On September 07, 2002 at 22:51:46, Robert Hyatt wrote: > >>On September 07, 2002 at 02:48:10, scott farrell wrote: >> >>>On September 06, 2002 at 21:38:23, Robert Hyatt wrote: >>>> >>>>Exactly how long does it take you to find the mate if _you_ play the >>>>rook move yourself? I mean you play the move and let your program search >>>>the resulting position here... >>>> >>>>Then we can figure out if your extensions are working by seeing how >>>>deep you have to go to find that mate from the white side after black >>>>blows it... >>> >>>The results of the rook search is below. >>> >>>I think I found it - my extensions when there is a nullthreat (ie. when the >>>nullmove returns <= -INFINITY) seemed to cause this search to go the entire >>>brute force distance of 12 plies to see the mate in 6. I am caching the >>>nullthreat in the hashtable as well. >> >> >>Here is a big question. How are you storing "depth" in the hash table? >> >>IE you aren't first adjusting for extensions and then storing that??? If >>so that's a bug... >> > >I am storing with depth as realdepth+extensions. I am using fractional depths, >and store the depth including the fractional part. > >I think that is correct I am not sure what you mean. But the answer is to look at your search code, and pick a position and ply where you are going to probe the hash table when you enter search. remember that number. Now assume you don't get a hit, so do a normal search, and look at the two ways to get out of search: (1) you get a fail high; (2) you don't. Make _sure_ that at each of those two places, you store the _same_ depth you used when you probed the table at the start of this search. If not, you have a problem...
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.