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Subject: Re: question for Bob Hyatt about iterate.c

Author: Robert Hyatt

Date: 08:46:41 11/26/03

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On November 26, 2003 at 00:53:50, Matthew McKnight wrote:

>Hi Bob,
>
>iterate.c
>
>In the iterative deepening algorithm, where you adjust your alpha and beta
>values for researching, i notice this fragment:
>
>
>        else if (value <= root_alpha) {
>   -----> if (!(root_moves[0].status&2)) {
>            root_moves[0].status&=255-128;
>            root_moves[0].nodes=0;
>            root_moves[0].status|=1;
>   ----->   if (root_moves[0].status&2) root_beta=MATE+1;
>
>            ..... //code omitted
>          }
>          else break;
>        }
>
>I drew arrows to the lines in question.  Correct me if I'm wrong, but isn't this
>a contradiction?  How will root_beta=MATE+1 ever be executed?  I'm looking for
>ideas on adjusting alpha/beta at the root, as my current scheme seems poor.  Is
>there something here I don't understand?
>
>Matt


The second if will obviously never be true.  Where that came from I don't know
but I'll look at it carefully tonight to see what the original intent was...



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