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PZChessBot 3.0 - new version chess engine



PZChessBot is a basic negamax engine.
Author: Kevin Lu 

v.3.0 What's Changed

What's Changed
Improve aspiration window logic by @kevlu8 in #51
add a soft time limit in ID loop by @kevlu8 in #52
Add futility pruning by @kevlu8 in #53
Vectorize nnue_eval() by @kevlu8 in #54
add spsa tuned values by @kevlu8 in #55
add gravity for history by @kevlu8 in #56
test adding capture history by @kevlu8 in #57
uncap rfp depth limit by @kevlu8 in #58
bench: 242114 add spsa values by @kevlu8 in #59
Input buckets ue by @kevlu8 in #60
Fix refreshing logic by @kevlu8 in #61
Precompute LMR tables by @kevlu8 in #62
Fix bug in castling handling in zobrist by @kevlu8 in #63
Add pawn correction history by @kevlu8 in #64
Add correction history for material by @kevlu8 in #65
Change network hidden layer size to 512 by @kevlu8 in #66
Change NMP to avoid pruning in non-pawn endgames by @kevlu8 in #67
Add static exchange evaluation in quiescence search by @kevlu8 in #68

STC:
Elo   | 211.83 +- 19.24 (95%)
Conf  | 8.0+0.08s Threads=1 Hash=32MB
Games | N: 1002 W: 602 L: 57 D: 343
Penta | [2, 15, 109, 186, 189]
https://sscg13.pythonanywhere.com/test/405/

LTC:
Elo   | 253.02 +- 18.50 (95%)
Conf  | 60.0+0.60s Threads=1 Hash=128MB
Games | N: 1000 W: 633 L: 11 D: 356
Penta | [0, 6, 65, 230, 199]

PzChessBot 2.0 vs other engines:

Emerald 0.3.02/2+22 Partii
Ironfang 1.02/2+22 Partii
Fridolin 4.00 JA2/2+22 Partii
Freda 1.12/2+22 Partii
Libra-chess 1.0.12/2+22 Partii
Kraken 2025-06-161.5/2+12 Partii
Maelstrom 2.1.01.5/2+12 Partii
Lunar 0.2.11/2+02 Partii
Halogen 130.5/2-12 Partii
Zangdar 4.04 JA0.5/2-12 Partii
Celeris 1.00/2-22 Partii
Fire 100/2-22 Partii
Stormphrax 7.0.00/2-22 Partii
Zangdar 4.040/2-22 Partii
Aku 2025.6.12 JA0/2-22 Partii
PlentyChess 6.0.5 JA0/2-22 Partii
Fire 9.3 JA0/2-22 Partii



Successes of the PZChessBot engine in our tournaments:


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