Re: [Bug-gnubg] SGF Double Analysis Format

[Guido Flohr]

On Tue, 2012-08-21 at 20:25 -0400, Ryan McKinnon wrote:
> I can clearly see that it's a 2ply evaluation, and note the wins,
> gammons, backgammons, and opponent's gammons and backgammons.  The
> item 0.243145 appears to be the cubeless equity, but I'm not sure how
> can I can calculate the cubeful no double and double/take equities

I forgot to answer your actual question. ;)

These values are computed in eval.c, FindCubeDecision().  The computed
equities/probabilities are then fed into FindBestCubeDecision() which
selects the proper cube action based on the equities/probabilities and
the current stand in the match (cube owner, dead cube,
pre-/post-Crawford, etc.).

The float[4] array arDouble holds the result.  The indices are explained
in eval.h:

/* Cubeful evalutions */
typedef enum {
  OUTPUT_OPTIMAL = 0,
  OUTPUT_NODOUBLE ,
  OUTPUT_TAKE,
  OUTPUT_DROP,
  N_CUBEFUL_OUTPUTS
} CubefulOutputs;

The two-dimensional array arOutput[2][7] contains the 14 last float
values from the DA property in the SGF file.

Guido
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