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Subject: Re: Nalimov TB question

Author: Gian-Carlo Pascutto

Date: 01:46:19 11/12/01

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On November 11, 2001 at 19:42:29, Bas Hamstra wrote:

>Is there any documentation about linking Nalimov?

probe.txt, which comes with the generator

>I am not sure what score a probe() should return. I set up a FINE that is a mate
>in 23 (verified on nalimov's online TB site). However, when my probing function
>returns 32756. Some debugging in TBIndex.cpp learns that initially it found 113
>that is then converted to 32756 by macro S_to_L. Doesn't seem right. Shouldn't
>it just return the number of moves to mate eventually? Peeking in Crafty seems
>to indicate so.

I figured out the conversion formula by setting up some positions
and looking at the values I got back until I figured it out.

In Sjeng, it looks like this:

if (tbScore == bev_broken) return KINGCAP;

  EGTBHits++;

  if (tbScore > 0)
  {
        return ((tbScore-bev_mi1)*2+INF-ply-1);
  }
  else if (tbScore < 0)
  {
        return ((tbScore+bev_mi1)*2-INF+ply);
  }
  return 0;

--
GCP



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