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Subject: Re: not using nullmove?

Author: Uri Blass

Date: 04:15:24 02/18/04

Go up one level in this thread

On February 18, 2004 at 06:38:33, Uri Blass wrote:

>On February 18, 2004 at 05:37:41, Tord Romstad wrote:
>>On February 17, 2004 at 20:55:13, Dann Corbit wrote:
>>>Here's a dumb idea:
>>>Write a program to scan a Nalimov database, but throw away everything except
>>>won/lost/drawn/broken (needs 2 bits per reflected board position to store the
>>>outcome state).
>>>Then write a table.
>>There are two problems with following this approach:
>>1. If you just use a table, you risk to miss the opportunity to discover
>>   principles which can be useful even in more complicated endgames.
>>2. The memory requirements are big.  A few MBs of RAM may not seem like a
>>   lot on modern computers, but it is not very aesthetically pleasing to
>>   use so much memory in order to do something as simple as evaluating
>>   KRKP endgames.  Besides, some of us (or at least one of us) want to
>>   port our engines to Palm OS and similar platforms, where memory is
>>   limited.
>I think that the first problem is KPK
>I still have 1843 positions white to move (pawns in a-d file) that the
>evaluation that I have now returns do not know.
>I wonder if your evaluation knows to detect win or draw in the following
>positions(I think the second position may be more easy to generalize a rule
>based on it):
>[D]8/k7/8/8/8/2P5/K7/8 w - - 0 1
>[D]8/8/1k6/8/8/3P4/K7/8 w - - 0 1
>[D]8/k7/8/8/8/3P4/K7/8 w - - 0 1

Note that I solved all 3 positions by adding 2 rules but I may be interested in
rules that people find because they may include more cases and help to make the
code smaller.


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