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Subject: Re: Question about Crafty output (Bob??)

Author: Robert Hyatt

Date: 05:40:11 04/20/05

Go up one level in this thread


On April 20, 2005 at 01:57:21, Jeremiah Penery wrote:

>On April 19, 2005 at 21:44:53, Les Fernandez wrote:
>
>>On April 19, 2005 at 21:20:27, Jeremiah Penery wrote:
>>
>>>On April 19, 2005 at 01:43:24, Les Fernandez wrote:
>>>
>>>>On April 19, 2005 at 00:41:36, Les Fernandez wrote:
>>>>
>>>>>On April 18, 2005 at 22:39:01, Robert Hyatt wrote:
>>>>>
>>>>>>On April 18, 2005 at 16:43:58, Les Fernandez wrote:
>>>>>>
>>>>>>>Can someone explain to me the differences in the following outputs by Crafty.
>>>>>>>These are some of the scenarios I came across.
>>>>>>>
>>>>>>>ce 1; pv;
>>>>>>>ce 0; pv;
>>>>>>>pv;
>>>>>>>ce 0;
>>>>>>>ce 1;
>>>>>>>
>>>>>>>Thanks,
>>>>>>>
>>>>>>>Les
>>>>>>
>>>>>>I don't know what that is.  the ce 1 usually means that one side is material
>>>>>>ahead, but the position is dead drawn.  ce 0 usually means equal material
>>>>>>draw...
>>>>>
>>>>>Hi Bob,
>>>>>
>>>>>Maybe I will post one position for each of the above outputs to see if you can
>>>>>qualify it Tuesday evening.  Thanks for your input.
>>>>>
>>>>>Les
>>>>
>>>>Decided to get them posted tonight <S>
>>>>
>>>>Here they are (actual output)
>>>>
>>>>k1K5/8/8/1R6/8/8/8/8 b - - acd 1; acn 1; acs 1; ce 0; pv Ka7;
>>>>k1K5/6R1/8/8/8/8/8/8 b - - acd 1; acn 1; acs 1; ce 1; pv;
>>>>k1K5/8/8/8/8/8/8/R7 b - - acd 1; acn 1; acs 1; ce -32767; pv;
>
>Ok, I looked more closely at these positions.  The second position has no legal
>moves, so it's a stalemate with no possible PV.  I don't know why the ce would
>be 1, however.  In the third position, black is already mated, so has no legal
>moves.  I'm looking through the source (I assume you're using Crafty compiled
>with the EPD support) to try and figure out why the first position isn't being
>analyzed properly (I get the same output as you did on my machine).


I responded to this yesterday, but somehow it didn't make it due to some sort of
network glitch I apparently overlooked.

Remember that crafty scores actual draws at -1, 0 and +1.  +1 means that the
position is a dead draw, but white is ahead in material.  This is an artifact of
"swindle mode" since given the choice of a draw with material down, or a draw
with material up, I want to be material up hoping my opponent will make a
mistake if he doesn't have endgame tables...

so the ce 1 just means that white is up material, in a dead drawn position.



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