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Subject: Re: Crafty Node Count Question

Author: Mike Byrne

Date: 19:28:57 11/12/04

Go up one level in this thread


On November 12, 2004 at 22:20:14, Uri Blass wrote:

>On November 12, 2004 at 22:04:34, Mike Byrne wrote:
>
>>sel 0 0 , ext set to 0
>>
>>sd=1
>>
>>Black(1): new
>>White(1): g
>>              time surplus   0.00  time limit 22.50 (3:30)
>>              depth   time  score   variation (1)
>>                1     0.00   0.16   1. Nf3
>>                1->   0.01   0.16   1. Nf3
>>              time=0.01  cpu=0%  mat=0  n=60  fh=100%  nps=10K
>>              ext-> chk=0 cap=0 pp=0 1rep=0 mate=0
>>              predicted=0  nodes=60  evals=20  50move=0
>>              endgame tablebase-> probes=0  hits=0
>>              SMP->  split=0  stop=0  data=0/128  cpu=0.00  elap=0.01
>>
>>White(1): Nf3
>>              time used:   0.01
>>
>>-> why 60 nodes here?
>>
>>( thought it would be 20)
>
>I can only guess that maybe the same node is searched again with different
>window.
>
>>
>>same settings, sd=2
>>
>>Black(1): new
>>White(1): sd 2
>>search depth set to 2.
>>White(1): g
>>              time surplus   0.00  time limit 22.50 (3:30)
>>              depth   time  score   variation (1)
>>                1     0.00   0.16   1. Nf3
>>                1->   0.02   0.16   1. Nf3
>>                2     0.02  -0.14   1. Nf3 Nc6
>>                2->   0.02  -0.14   1. Nf3 Nc6
>>              time=0.02  cpu=0%  mat=0  n=119  fh=100%  nps=10K
>>              ext-> chk=0 cap=0 pp=0 1rep=0 mate=0
>>              predicted=0  nodes=119  evals=59  50move=0
>>              endgame tablebase-> probes=0  hits=0
>>              SMP->  split=0  stop=0  data=0/128  cpu=0.00  elap=0.02
>>
>>White(1): Nf3
>>              time used:   0.02
>>Black(1):
>>
>>-> why 119 nodes here
>>
>>I thought it would be 400.
>
>No reason for 400
>alphabeta with no pruning and extensions means that you save time by not
>searching illogical lines and after finding that 1.Nf3 is 0.14 pawns for black
>and finding that 1.a3 e5 is 0.20 pawns for black you save time by not searching
>1.a3 d5 because 1.a3 is not better for white than 0.2 pawns for black and
>finding it's exact score is waste of time.
>
>Uri


thanks ...



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