Author: Harald Lüßen
Date: 10:21:48 03/06/06
Go up one level in this thread
On March 06, 2006 at 06:03:45, giuseppe wrote: >in heinz's book scalable search at pag. 21 there is the UPPER variable uses in >transposition table algorithm. What is it? is returned from the function? > >thank >g.c. In the search() it is initialised with +infinite_val. (Top of fig. 0.8 p. 21) It is lowered if we know a real upper score of this position from the transposition table. (Bottom of fig. 0.8 p. 21) May be it is lowered when we see other limits in the search. Read pages 68 to 70. There the upper value is updated with recognizer results. Alpha and beta give us an interval in which we want to be, score and upper are the interval we find during the search for the current position. Read 0.3.2 Transposition Tables on page 22. Heinz writes: "Eventual fail-high cutoffs later respect this upper bound by returning the minimum of upper and the best score so far as their result." Harald
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.