Author: Inmann Werner
Date: 01:13:10 10/08/99
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On October 07, 1999 at 23:40:21, Bruce Moreland wrote: >On October 07, 1999 at 20:45:08, James Robertson wrote: > >>My search currently decides a position is drawn if it has repeated twice. I >>think this is causing my search to sometimes stuff 2nd rep draw values into the >>hash table that can be retrieved for positions with different history's. Is this >>a problem? What do other people do? Could I just not store any draw values in >>the hash table? Should I go to draw by 3rd rep? > >Don't store it, since it can only cause problems if you do. > >But your problems won't end if you don't store these scores, since a large >portion of the tree can potentially be affected by the presence of repetitions. > >The bottom line is that you can't completely solve this problem. What will >happen is that when you re-search a position that failed high, it might fail >low, which you'd think should be impossible. You can't fix this, all you can do >is come up with a way not to explode when it happens. > >bruce Nice description :) I exploded more than one time. I have one line in my code to avoid storing repetition code or allow it, and depending on my "explodes" I change them. It is really ugly. Not storing causes problems, all getting slow, storing sometimes produces trash... If I store it, my program gets better in getting draws in "lost positions" but looses games at other times... GRRR! I tried some thing, which is not bad, but ugly. I give draw by repetition a "special value" and store it to hashtables for sorting. If I disable "storing" I do not loose the move ordering, but it is also ugly, cause it does not work really (clear why?). It is all GRRR! Werner
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