61 lines
1.6 KiB
Python
61 lines
1.6 KiB
Python
import random
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from abc import ABC, abstractmethod
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from typing import Self
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import chess
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from chesspp.i_strategy import IStrategy
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class IMctsNode(ABC):
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def __init__(self, board: chess.Board, strategy: IStrategy, parent: Self | None, move: chess.Move | None,
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random_state: random.Random):
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self.board = board
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self.strategy = strategy
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self.parent = parent
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self.children = []
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self.move = move
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self.legal_moves = list(board.legal_moves)
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self.random_state = random_state
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@abstractmethod
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def select(self) -> Self:
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"""
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Selects the next node leaf node in the tree
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:return:
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"""
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pass
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@abstractmethod
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def expand(self) -> Self:
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"""
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Expands this node creating X child leaf nodes, i.e., choose an action and apply it to the board
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:return:
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"""
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pass
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@abstractmethod
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def rollout(self, rollout_depth: int = 20) -> int:
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"""
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Rolls out the node by simulating a game for a given depth.
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Sometimes this step is called 'simulation' or 'playout'.
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:return: the score of the rolled out game
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"""
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pass
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@abstractmethod
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def backpropagate(self, score: float | None = None) -> None:
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"""
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Backpropagates the results of the rollout
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:param score:
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:return:
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"""
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pass
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def update_depth(self, depth: int) -> None:
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"""
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Recursively updates the depth the current node and all it's children
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:param depth: new depth for current node
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:return:
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"""
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