Package ai.nettogrof.battlesnake.treesearch

Class AbstractMCTS

java.lang.Object

ai.nettogrof.battlesnake.treesearch.AbstractSearch

ai.nettogrof.battlesnake.treesearch.AbstractBestFirstSearch

ai.nettogrof.battlesnake.treesearch.AbstractMCTS

All Implemented Interfaces:

Runnable

Direct Known Subclasses:

AbstractRoyaleSearch, AbstractSquadSearch, AbstractStandardSearch, ConstrictorSearch

public abstract class AbstractMCTS
extends AbstractBestFirstSearch

This abstract MCTS search, provide basic method use in any search using MCTS type of search

Version:

Spring 2021

Author:

carl.lajeunesse

Field Summary

Fields inherited from class ai.nettogrof.battlesnake.treesearch.AbstractSearch

cont, height, root, rules, startTime, timeout, width

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractMCTS()	Sole constructor.

Method Summary

Modifier and Type	Method	Description
protected void	executeMCTS()	Execute the MCTS search
private void	fillMCTSList(gnu.trove.list.array.TFloatArrayList upward, gnu.trove.list.array.TFloatArrayList down, gnu.trove.list.array.TFloatArrayList left, gnu.trove.list.array.TFloatArrayList right, AbstractNode node)	This method fill 4 list (one for each direction ) with the score of each node based on the move direction
protected List<AbstractNode>	getMCTSBestPath(AbstractNode node)	This method is use to find the next leaf node to explore using MCTS algo
private float	mctsScore(AbstractNode parentNode, AbstractNode childNode)	Calculation of the Upper Confident Bound score.

Methods inherited from class ai.nettogrof.battlesnake.treesearch.AbstractBestFirstSearch

getBestChild, getbestChildValue, getBestPath, mergeList, updateFullListNode, updateListNode

Methods inherited from class ai.nettogrof.battlesnake.treesearch.AbstractSearch

addMove, checkHeadToHead, createSnakeInfo, freeSpace, generateChild, generateChild, generateSnakeInfoDestination, getSmallestChild, kill, merge, moveSnake, stopSearching

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.lang.Runnable

run

Constructor Detail

AbstractMCTS

protected AbstractMCTS()

Sole constructor. (For invocation by subclass constructors, typically implicit.)

Method Detail

getMCTSBestPath

protected List<AbstractNode> getMCTSBestPath(AbstractNode node)

This method is use to find the next leaf node to explore using MCTS algo

Parameters:

node - The root node

Returns:

List of node from the leaf to the root

mctsScore

private float mctsScore(AbstractNode parentNode,
                        AbstractNode childNode)

Calculation of the Upper Confident Bound score.

Parameters:

parentNode - the parent node

childNode - the child node which is the score is calculated

Returns:

float of the score.

fillMCTSList

private void fillMCTSList(gnu.trove.list.array.TFloatArrayList upward,
                          gnu.trove.list.array.TFloatArrayList down,
                          gnu.trove.list.array.TFloatArrayList left,
                          gnu.trove.list.array.TFloatArrayList right,
                          AbstractNode node)

This method fill 4 list (one for each direction ) with the score of each node based on the move direction

Parameters:

upward - float array list

down - float array list

left - float array list

right - float array list

node - parent node

executeMCTS

protected void executeMCTS()

Execute the MCTS search