Author: Andreas Herrmann
Date: 12:21:11 11/22/02
Go up one level in this thread
On November 22, 2002 at 14:11:40, Tony Werten wrote: >On November 22, 2002 at 12:58:42, Andreas Herrmann wrote: > >>On November 22, 2002 at 11:35:38, Tony Werten wrote: >> >>>On November 22, 2002 at 10:39:16, Uri Blass wrote: >>> >>>>On November 22, 2002 at 10:30:34, Robert Hyatt wrote: >>>> >>>>>On November 22, 2002 at 07:21:13, Uri Blass wrote: >>>>> >>>>>>On November 22, 2002 at 05:50:09, Omid David Tabibi wrote: >>>>>> >>>>>>>Vincent, >>>>>>> >>>>>>>You haven't read the article yet. READ IT. I have described everything I have >>>>>>>done quite clearly, and have presented the results. All the node counts are also >>>>>>>available at my website. >>>>>>> >>>>>>>Regarding your checkmate question: except for the "Mate in 4" and "Mate in 5" >>>>>>>positions which I was interested to know only if the checkmating was found or >>>>>>>not, in all other test positions (ECM, WCS, Neishtadt) the search was conducted >>>>>>>to the mentioned depth even if a checkmate is found at eariler plies. This was >>>>>>>done in order to ensure that the fixed depth results are comparable in terms of >>>>>>>tree size. >>>>>>> >>>>>>>Omid. >>>>>> >>>>>>What do you search after finding a mate? >>>>>>Does genesis search for a shorter mate and in this case does it knows not to >>>>>>search when it get ply that means that no shorter mate can be found? >>>>>> >>>>>>Movei simply stop searching after finishing an iteration with mate score. >>>>>> >>>>>>Uri >>>>> >>>>> >>>>>I would suspect he does like most everyone else. Search until you reach depth >>>>>2*N-1 where N is the mate depth as in mate in 9. I need to search 17 plies to >>>>>verify that no shorter mate than mate in 9 exists... >>>> >>>>I do not know what most do but I do not care after finding a mate to find the >>>>shorter mate. >>>> >>>>The result is the same even if I do not find the shortest mate. >>>>I care only to finish the iteration. >>> >>>You'll care when you add tablebase support. >>> >>>When there are 6 pieces on the board and your program sacrifies his queen to >>>find a checkmate in 123, you'd wish it had searched a bit longer to find the >>>mate in 4. >> >>Hi Tony, >> >>but then you must be in depth 245 to cut the search by checkmate in 123 and >>search abort after 2*N-1. > >No, if you can't find anything better then you take the checkmate in 123. But if >you allocated fe 2 minutes, you can spend that time to find a shorter one. I >started with this idea when I saw Fritz make exactly this mistake. It's not too >bad, it just looks silly. > >> >>In previous versions i have also finished the search after 2*N-1. In my current >>version i finish my search after 2*N+2, because of Nullmove and other pruning >>algos. But it's mainly interresting to search a little bit deeper if there was >>found a mate for the opponent, perhaps in some rare cases a draw will be find 2 >>or 3 plys deeper. >> >>Andreas >> >>PS: Thanks again for your DLL. Works fine :) > >You're welcome. Please don't forget to drop Eugene an email. The dll gives acces >to his tables, so you should let him know/ask permission. (Theoreticly the >latter, practicly the first ) Yes i know. I have asked Eugene last week per email, and have got one day later the permission by him and Andrew. Much thanks to Eugene and Andrew. Andreas > >Tony
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