kate/BadFish
1
0
Fork 0
mirror of https://github.com/sockspls/badfish synced 2025-04-30 00:33:09 +00:00
Code Issues Releases Wiki Activity

Document why initing eval tables

Browse source 
Instead of hard-code the weights in a big table,
we prefer to calculate them out of few parameters
at startup. This allows to keep low the number of
independent parameters and hence is good for tuning
and for a better insight in the meaning of the numbers.

No functional change.
This commit is contained in:
Marco Costalba 2014-10-13 09:23:21 +02:00 • committed by Joona Kiiski
parent 89d9db2979
commit 480682b670
1 changed files with 10 additions and 5 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

15
src/pawns.cpp
View file

@ -194,19 +194,24 @@ namespace {
namespace Pawns {
/// init() initializes some tables used by evaluation. Instead of hard-coded
/// tables, when makes sense, we prefer to calculate them with a formula to
/// reduce independent parameters and to allow easier tuning and better insight.
void init()
{
const int c[RANK_NB] = {0, 6, 15, 10, 57, 75, 135, 258};
static const int Seed[RANK_NB] = { 0, 6, 15, 10, 57, 75, 135, 258 };
for (Rank r = RANK_2; r <= RANK_7; ++r)
for (int opposed = false; opposed <= true; ++opposed)
for (int phalanx = false; phalanx <= true; ++phalanx)
for (int opposed = 0; opposed <= 1; ++opposed)
for (int phalanx = 0; phalanx <= 1; ++phalanx)
for (Rank r = RANK_2; r < RANK_8; ++r)
{
int bonus = c[r] + (phalanx ? (c[r + 1] - c[r]) / 2 : 0);
int bonus = Seed[r] + (phalanx ? (Seed[r + 1] - Seed[r]) / 2 : 0);
Connected[opposed][phalanx][r] = make_score(bonus / 2, bonus >> opposed);
}
}
/// probe() takes a position as input, computes a Entry object, and returns a
/// pointer to it. The result is also stored in a hash table, so we don't have
/// to recompute everything when the same pawn structure occurs again.