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Subject: Re: MTD: an observation and a question

Author: Dieter Buerssner

Date: 12:07:46 09/13/02

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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.

>>>     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.


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