Confused by futility pruning
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hgm
- Posts: 27814
- Joined: Fri Mar 10, 2006 10:06 am
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- Full name: H G Muller
Re: Confused by futility pruning
I don't think that pruning at d>3 can be called futility pruning. Even at d=3 the more commony used term is 'razoring'.
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metax
- Posts: 344
- Joined: Wed Sep 23, 2009 5:56 pm
- Location: Germany
Re: Confused by futility pruning
As far as I know, razoring is something completely different, namely evaluate all moves, sort them in decreasing order, and stop searching once the evaluation of a move is < alpha. This is much riskier than futility pruning, especially at higher depths.
Another definition of razoring is to do a qsearch if the static evaluation is much below alpha, and if the result of the qsearch does not exceed alpha, the branch is pruned. According to the chess programming wiki this is called 'Hyatt's Razoring', but as far as I know he does no longer do this.
Another definition of razoring is to do a qsearch if the static evaluation is much below alpha, and if the result of the qsearch does not exceed alpha, the branch is pruned. According to the chess programming wiki this is called 'Hyatt's Razoring', but as far as I know he does no longer do this.