Programming

Forum Archive : Programming

 
N-ply algorithm

From:   eXtreme Gammon
Address:   contact@extremegammon.com
Date:   23 January 2011
Subject:   N-ply Algorithm
Forum:   BGonline.org Forums

The N-ply Algorithm is pretty straight forward:

* for each 21 dice,

  + check if player should double (using N-ply) and move the cube position

    * if N=1,

      + Get the cubeless equity from the NN
      + convert to Cubeful using Janowski formula

    * else

      + get the best move using a 1-ply
      + make the move selected
      + do a (N-1)-ply evaluation of the resulting position

* accumulate the result, weighing them (1/36 for double, 2/36 otherwise)

* return to caller

So yes, a 7-ply will check all 21^6=85,766,121 dice possible.
 
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