Author: Uri Blass
Date: 04:57:17 07/30/02
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On July 30, 2002 at 07:28:42, Uri Blass wrote: >On July 29, 2002 at 17:39:53, Uri Blass wrote: > ><snipped> >>I am going to write it in valid C but first I need to understand what I need to >>store in the hash tables when the depth is 0 and when to store moves that lead >>to exact scores and how to do it. >> >>Uri > >I think that I know the problem that caused >my program to be slower after adding exact scores. > >The remaining depth when I call qsearch can >be smaller than 0 because of null move pruning >(it was no problem in regular search because >in that case I call qsearch when the remaining depth >is 0 but it was a problem when I tried to probe >the hash tables with the remaining depth. > >I think that I will change the line >val=-alphabeta(depth-4,-beta,-beta+1); >to the line >if (depth>=4) >val=-alphabeta(depth-4,-beta,-beta+1); >else >val=-quies(...) When I think about it again I may extend by more than one ply so even if (depth>=4) may be not exactly the same as without it(in the position that I tested it was the same but I think that there may be cases when it is not the same). I wonder if it may be a good idea to change the order in my alphabeta and first calculate extensions and only later call alphabeta. In that case I can record a more exact depth in the hash tables. Today the exact depth may be dependent on the previous moves and not only on the position (in most cases previous moves do not change but in case that they are captures or pawn to the 7th they may change) Today the varaible depth that I record in the hash tables does not give the full information about the depth because there is another varaible for partial extensions. I do not know if it is a good idea to store the partial extensions because in that case it means that I have less space in the hash tables. Uri
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