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Subject: Re: Hashkey collisions (typical numbers)

Author: Renze Steenhuisen

Date: 08:12:23 04/07/04

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>As would I.  This has been tested over and over and over.  64 bit signatures
>won't produce signature collisions every 7M nodes without a serious bug or very
>poor random numbers...

Alright, I agree...

I am using TWO-DEEP as a replacement scheme.
    (move the first two the second entry when new data has a higher draft,
     else overwrite second)
Not clearing the hashtable between iteration, just between succeeding searches.

I checked all do_move's and undo_move's by comparing the incremental hashkey
with the fresh-from-scratch generated hashkey before AND after every call,
including NULL-move.

I am using the same random number generator as Crafty is.

I rechecked the values that are used:
Overall:
  ~50%  0's
  ~50%  1's
Per bit-position over all 368 keys (P=48, N=64, B=64, R=64, Q=64, K=64)
all have
  ~50%  0's
  ~50%  1's

I am desperate for help!

Renze



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