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Subject: Re: MTD: an observation and a question

Author: martin fierz

Date: 13:01:55 09/13/02

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On September 13, 2002 at 15:07:46, Dieter Buerssner wrote:

>On September 12, 2002 at 18:30:07, martin fierz wrote:
>
>>On September 12, 2002 at 16:50:38, Dieter Buerssner wrote:
>>
>>>On September 12, 2002 at 16:10:38, martin fierz wrote:
>>>
>>>>bestvalue = -mate;
>>>>for all moves do
>>>>  {
>>>>  value = -search(-beta,-alpha,etc);
>>>>  bestvalue = max(value, bestvalue);
>>>   alpha = max(value, alpha);
>>>>  if(value>beta)
>
>Oops. As Uli pointed out, this should of course be >=. But we can blame Robert
>Hyatt for this one :-) I just copy pasted from his post, and you probably did
>the same.

right :-)
i did check back in my code though, just to make sure it was ok there...

aloha
  martin

>>>>     break;
>>>>  }
>>>>return bestvalue;
>>>>
>>>>is there anything wrong with this?
>>>
>>>Pehaps you left it out on purpose - but this code snipped is missing an update
>>>of alpha. For example at the place, I suggested above.
>>
>>hi dieter,
>>
>>you are right, i left it out, half on purpose i guess. it just seemed irrelevant
>>to the return value. but it's in my code - although it's really unnecessary: in
>>MTD you always fail, so you never have to update alpha.
>
>Another oops. I totally forgot the context of the post (which is quite clearly
>shown in the title). I of course totally agree with you.
>
>Cheers,
>Dieter



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