Author: Robert Hyatt
Date: 07:03:10 10/14/03
Go up one level in this thread
On October 14, 2003 at 02:28:30, José Carlos wrote: >On October 13, 2003 at 15:02:05, Robert Hyatt wrote: > >>On October 13, 2003 at 12:57:04, José Carlos wrote: >> >>>On October 13, 2003 at 12:03:32, Vincent Diepeveen wrote: >>> >>>>On October 13, 2003 at 11:31:11, Robert Hyatt wrote: >>>> >>>>>On October 13, 2003 at 09:29:47, Vincent Diepeveen wrote: >>>>> >>>>> >>>>>> >>>>>>there are very big differences. >>>>>> >>>>>> >>>>> >>>>>There isn't a big difference if you are only talking about the q-search. >>>>> >>>>>If you do a check, you have to get out and that extends. If you extend >>>>>on the check you don't extend when you get out and that extends. >>>>> >>>>>It is different in the normal part of the search, because if you extend on >>>>>a check you increase depth by one now. You might reach the q-search if you >>>>>wait to extend when you escape check. but in the q-search I don't see how it >>>>>is a "big difference". >>>> >>>>You don't have to apologize for not knowing basic tree math, you're excused. >>>>Had seen already in crafty code that it was done wrong there. >>>> >>>>Yet i had already posted years ago at CCC that if you extend when being checked, >>>>that this is better than when giving the check. >>>> >>>>What delivers more cutoffs for the hashtable: >>>> >>>>A) >>>>Re5+ (5 ply remaining) >>>>Kf7 (5 ply remaining) >>>>Rxa5 (4 ply remaining) >>>> >>>>B) >>>>Re5+ (5 ply remaining) >>>>Kf7 (4 ply remaining) >>>>Rxa5 (4 ply remaining) >>>> >>>>If you can answer that question then you'll know the answer to the basic tree >>>>searching question. >>>> >>>>Best regards, >>>>Vincent >>> >>> >>> Do you cutoff in moves or in positions? >>> If you cutoff in positions, then you have: >>> >>>Extend check: >>> >>>A -Re5+-> B -Kf7-> C -Rxa5-> D >>>5 5 4 3 (depth remaining) >>> >>> >>>Extend out-of-check: >>> >>>A -Re5+-> B -Kf7-> C -Rxa5-> D >>>5 4 4 3 (depth remaining) >>> >>> So the only difference is position B. In the first case you store depth 5 in >>>the hash table, in the sencond case, 4. >>> In principle it seems that extending checks would give more cutoffs due to >>>hash table, but to get to position B you need a checking move, which would >>>extend (increase remaining depth) in the first case, and not extend in the >>>second. >>> The result seems to be that both will work the same, except for leaf nodes, as >>>Bob pointed. >>> >>> José C. >> >> >>Don't fall into his trap. In the q-search, which I _explicitly_ said I was >>talking about exclusively, there is no "depth remaining" to extend. His >>comments are, as always, nonsensical. >> >>If we were talking about the basic search, then things are a bit different. >>But I do it my way there for a reason. It guarantees that I _never_ reach >>the q-search when the side-to-move's king is in check. >> >>But we weren't talking about that case in what I wrote and where Vincent >>responded with a completely random comment. > > But I think he's also wrong for the main search, because for interior nodes, >assuming as Omid pointed, a correct use of the hash table, the result must be >exaclty the same. > I expect Vincent to understand it, but not to admit he was wrong for so many >years. > > José C. Don't ever expect him to admit such a thing. remember the golden rule: "anything Vincent can't do or understand is impossible". Then you will truly understand him and his many idiotic comments.
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.