Editing Parameters.txt

You can tune Ntest in a number of ways by editing the file parameters.txt.

Line 1: Machine Parameters

The format of the first line is
<RAM for hashtable in MB>  <speed of computer in GHz>
I use 70MB hashtable on a 128 MB machine and 7MB hashtable on a 64MB machine. If the hard drive starts thrashing, you've set it too high.

Lines 2 and 3: Computer 1 and 2

Ntest now has 2 computer player slots, so you can play different books against each other. To specify parameters for computers 1 and 2, you edit the second and third line of params.txt. An example line looks like this:

JA s21 100 -100 0 0 1 1 -1 -1

The parameters are, in order,
coefficient setJA currently.
search paramssee SearchParams
blackDrawValue, whiteDrawValueIn the example, the black draw value is +100 discs (black seeks draws) and the white draw value is -100 discs (white avoids draws). Another popular value is 0, which is the way wzebra works. (Full-strength Zebra has black seeks/avoids draws options just like ntest).
blackRand, whiteRandThese both use my screwy rand system where randomness is 2rand discs, so 0 means 1 disc randomness.
book flagif set to 0, the computer will play without using a book (and will not add the games to book).
negamax flagif set to 1, the computer will check its book for transpositions when it loads it.
display book values for me, opponentif set to 0, will display no book info. -1 to display all info.

Line 4+: Additional options

Additional options can be given below the first 3 lines of parameters.txt, one per line. An example line is
BookWriteFormat 2
which will store the book in compressed format.
Option lineDefaultDescription
BookWriteFormat {#}2 1: store in old uncompressed format.
2: store in compressed format
EdmundLevel {#}1 Edmund level for redoing close games. This is a sum of the following flags:
  • 1 Edmundize probable solve nodes
  • 2 Edmundize midgame nodes
  • 4 Edmundize draw nodes even if a draw has already been played
DrawTreeLimit {draw} {deviation} draw=3.00
deviation=3.50
Sets the maximum value of nodes that will be expanded in draw tree search mode.