Node used in SgUctTree. More...

#include <SgUctTree.h>

Public Member Functions
	SgUctNode (const SgUctMoveInfo &info)
	Initializes node with given move, value and count.
void	AddGameResult (SgUctValue eval)
	Add game result.
void	AddGameResults (SgUctValue eval, SgUctValue count)
	Adds a game result count times.
void	MergeResults (const SgUctNode &node)
	Add other nodes results to this node's.
void	RemoveGameResult (SgUctValue eval)
	Removes a game result.
void	RemoveGameResults (SgUctValue eval, SgUctValue count)
	Removes a game result count times.
SgUctValue	PosCount () const
	Number of times this node was visited.
SgUctValue	MoveCount () const
	Number of times the move leading to this position was chosen.
const SgUctNode *	FirstChild () const
	Get first child.
bool	HasChildren () const
	Does the node have at least one child?
SgUctValue	Mean () const
	Average game result.
bool	HasMean () const
	True, if mean value is defined (move count not zero).
int	NuChildren () const
	Get number of children.
void	SetFirstChild (const SgUctNode *child)
	See FirstChild().
void	SetNuChildren (int nuChildren)
	See NuChildren().
void	IncPosCount ()
	Increment the position count.
void	IncPosCount (SgUctValue count)
	Increment the position count.
void	DecPosCount ()
	Decrement the position count.
void	DecPosCount (SgUctValue count)
	Decrement the position count.
void	SetPosCount (SgUctValue value)
void	InitializeValue (SgUctValue value, SgUctValue count)
	Initialize value with prior knowledge.
void	CopyDataFrom (const SgUctNode &node)
	Copy data from other node.
SgMove	Move () const
	Get move.
SgUctValue	RaveCount () const
	Get RAVE count.
SgUctValue	RaveValue () const
	Get RAVE mean value.
bool	HasRaveValue () const
void	AddRaveValue (SgUctValue value, SgUctValue weight)
	Add a game result value to the RAVE value.
void	RemoveRaveValue (SgUctValue value)
	Removes a rave result.
void	RemoveRaveValue (SgUctValue value, SgUctValue weight)
void	InitializeRaveValue (SgUctValue value, SgUctValue count)
	Initialize RAVE value with prior knowledge.
int	VirtualLossCount () const
void	AddVirtualLoss ()
void	RemoveVirtualLoss ()
SgUctValue	KnowledgeCount () const
	Returns the last time knowledge was computed.
void	SetKnowledgeCount (SgUctValue count)
	Set that knowledge has been computed at count.
bool	IsProven () const
	Returns true if node is a proven node.
bool	IsProvenWin () const
bool	IsProvenLoss () const
SgUctProvenType	ProvenType () const
void	SetProvenType (SgUctProvenType type)
Private Attributes
SgUctStatisticsVolatile	m_statistics
const SgUctNode *volatile	m_firstChild
volatile int	m_nuChildren
volatile SgMove	m_move
SgUctStatisticsVolatile	m_raveValue
	RAVE statistics.
volatile SgUctValue	m_posCount
volatile SgUctValue	m_knowledgeCount
volatile SgUctProvenType	m_provenType
volatile int	m_virtualLossCount

Detailed Description

Node used in SgUctTree.

All data members are declared as volatile to avoid that the compiler re-orders writes, which can break assumptions made by SgUctSearch in lock-free mode (see Lock-free mode in SgUctSearch). For example, the search relies on the fact that m_firstChild is valid, if m_nuChildren is greater zero or that the mean value of the move and RAVE value statistics is valid if the corresponding count is greater zero.

Definition at line 111 of file SgUctTree.h.

Constructor & Destructor Documentation

SgUctNode::SgUctNode ( const SgUctMoveInfo & info )

Initializes node with given move, value and count.

Definition at line 270 of file SgUctTree.h.

Member Function Documentation

void SgUctNode::AddGameResult ( SgUctValue eval )

Add game result.

Parameters:

eval

The game result (e.g. score or 0/1 for win loss)

Definition at line 283 of file SgUctTree.h.

References SgStatisticsVltBase< VALUE, COUNT >::Add(), and m_statistics.

void SgUctNode::AddGameResults	(	SgUctValue	eval,
		SgUctValue	count
	)

Adds a game result count times.

Definition at line 288 of file SgUctTree.h.

References SgStatisticsVltBase< VALUE, COUNT >::Add(), and m_statistics.

void SgUctNode::AddRaveValue	(	SgUctValue	value,
		SgUctValue	weight
	)

Add a game result value to the RAVE value.

See also:: SgUctSearch::Rave().

Definition at line 311 of file SgUctTree.h.

References SgStatisticsVltBase< VALUE, COUNT >::Add(), and m_raveValue.

void SgUctNode::AddVirtualLoss ( )

Definition at line 363 of file SgUctTree.h.

References m_virtualLossCount.

void SgUctNode::CopyDataFrom ( const SgUctNode & node )

Copy data from other node.

Copies all data, apart from the children information (first child and number of children).

Definition at line 326 of file SgUctTree.h.

References m_knowledgeCount, m_move, m_posCount, m_provenType, m_raveValue, m_statistics, and m_virtualLossCount.

Referenced by SgUctTree::ApplyFilter(), SgUctTree::CopySubtree(), and SgUctTree::SetChildren().

void SgUctNode::DecPosCount ( )

Decrement the position count.

See PosCount()

Definition at line 386 of file SgUctTree.h.

References m_posCount.

void SgUctNode::DecPosCount ( SgUctValue count )

Decrement the position count.

See PosCount()

Definition at line 395 of file SgUctTree.h.

References m_posCount.

const SgUctNode * SgUctNode::FirstChild ( ) const

Get first child.

Note:: This information is an implementation detail of how SgUctTree manages nodes. Use SgUctChildIterator to access children nodes.

Definition at line 337 of file SgUctTree.h.

References HasChildren(), m_firstChild, and SG_ASSERT.

Referenced by SgUctTree::MergeChildren(), SgUctSearch::SelectChild(), and SgUctChildIterator::SgUctChildIterator().

bool SgUctNode::HasChildren ( ) const

Does the node have at least one child?

Definition at line 343 of file SgUctTree.h.

References m_nuChildren.

Referenced by SgUctTree::ApplyFilter(), SgUctTreeStatistics::Compute(), SgUctTree::CopySubtree(), SgUctTree::CreateChildren(), SgUctSearch::FindBestChild(), SgUctSearch::FindBestSequence(), SgUctTreeUtil::FindChildWithMove(), FirstChild(), SgUctTree::MergeChildren(), SgUctTreeIterator::operator++(), SgUctSearch::PlayInTree(), SgUctSearch::PrintSearchProgress(), SgUctSearch::SelectChild(), SgUctTree::SetChildren(), and SgUctChildIterator::SgUctChildIterator().

bool SgUctNode::HasMean ( ) const

True, if mean value is defined (move count not zero).

Definition at line 348 of file SgUctTree.h.

References SgStatisticsVltBase< VALUE, COUNT >::IsDefined(), and m_statistics.

Referenced by SgUctSearch::CheckEarlyAbort(), SgUctTreeStatistics::Compute(), SgUctSearch::FindBestChild(), SgUctSearch::GetValueEstimate(), and SgUctSearch::GetValueEstimateRave().

bool SgUctNode::HasRaveValue ( ) const

Definition at line 353 of file SgUctTree.h.

References SgStatisticsVltBase< VALUE, COUNT >::IsDefined(), and m_raveValue.

Referenced by SgUctTreeStatistics::Compute(), SgUctSearch::FindBestChild(), SgUctSearch::GetValueEstimate(), and SgUctSearch::GetValueEstimateRave().

void SgUctNode::IncPosCount ( SgUctValue count )

Increment the position count.

See PosCount()

Definition at line 381 of file SgUctTree.h.

References m_posCount.

void SgUctNode::IncPosCount ( )

Increment the position count.

See PosCount()

Definition at line 376 of file SgUctTree.h.

References m_posCount.

void SgUctNode::InitializeRaveValue	(	SgUctValue	value,
		SgUctValue	count
	)

Initialize RAVE value with prior knowledge.

Definition at line 409 of file SgUctTree.h.

References SgStatisticsVltBase< VALUE, COUNT >::Initialize(), and m_raveValue.

void SgUctNode::InitializeValue	(	SgUctValue	value,
		SgUctValue	count
	)

Initialize value with prior knowledge.

Definition at line 404 of file SgUctTree.h.

References SgStatisticsVltBase< VALUE, COUNT >::Initialize(), and m_statistics.

bool SgUctNode::IsProven ( ) const

Returns true if node is a proven node.

Definition at line 476 of file SgUctTree.h.

References m_provenType.

Referenced by SgUctSearch::CheckAbortSearch(), SgUctTree::CopySubtree(), SgUctSearch::PlayInTree(), and SgUctSearch::PropagateProvenStatus().

bool SgUctNode::IsProvenLoss ( ) const

Definition at line 486 of file SgUctTree.h.

References m_provenType.

Referenced by SgUctSearch::FindBestChild(), and SgUctSearch::PropagateProvenStatus().

bool SgUctNode::IsProvenWin ( ) const

Definition at line 481 of file SgUctTree.h.

References m_provenType.

Referenced by SgUctSearch::CheckAbortSearch(), and SgUctSearch::SelectChild().

SgUctValue SgUctNode::KnowledgeCount ( ) const

Returns the last time knowledge was computed.

Definition at line 466 of file SgUctTree.h.

References m_knowledgeCount.

Referenced by SgUctTree::MergeChildren(), SgUctSearch::NeedToComputeKnowledge(), and SgUctSearch::PlayInTree().

SgUctValue SgUctNode::Mean ( ) const

Average game result.

Requires: HasMean()

Definition at line 414 of file SgUctTree.h.

References m_statistics, and SgStatisticsVltBase< VALUE, COUNT >::Mean().

Referenced by SgUctSearch::CheckEarlyAbort(), SgUctTreeStatistics::Compute(), SgUctSearch::FindBestChild(), SgUctSearch::GetValueEstimate(), SgUctSearch::GetValueEstimateRave(), SgUctSearch::PrintSearchProgress(), SgUctSearch::Search(), and SgUctSearch::SummaryLine().

void SgUctNode::MergeResults ( const SgUctNode & node )

Add other nodes results to this node's.

Definition at line 293 of file SgUctTree.h.

References SgStatisticsVltBase< VALUE, COUNT >::Add(), SgStatisticsVltBase< VALUE, COUNT >::Count(), SgStatisticsVltBase< VALUE, COUNT >::IsDefined(), m_raveValue, m_statistics, and SgStatisticsVltBase< VALUE, COUNT >::Mean().

Referenced by SgUctTree::MergeChildren().

SgMove SgUctNode::Move ( ) const

Get move.

Requires: Node has a move (is not root node)

Definition at line 419 of file SgUctTree.h.

References m_move, SG_ASSERT, and SG_NULLMOVE.

Referenced by SgUctTree::ApplyFilter(), SgUctSearch::CheckCountAbort(), SgUctSearch::FindBestChild(), SgUctSearch::FindBestSequence(), SgUctTreeUtil::FindChildWithMove(), SgUctTree::MergeChildren(), SgUctSearch::PlayInTree(), SgUctSearch::PrintSearchProgress(), SgUctSearch::SummaryLine(), and SgUctSearch::UpdateRaveValues().

SgUctValue SgUctNode::MoveCount ( ) const

Number of times the move leading to this position was chosen.

This count will be different from PosCount(), if prior knowledge initialization is used.

Definition at line 425 of file SgUctTree.h.

References SgStatisticsVltBase< VALUE, COUNT >::Count(), and m_statistics.

Referenced by SgUctSearch::CheckAbortSearch(), SgUctSearch::CheckCountAbort(), SgUctSearch::CheckEarlyAbort(), SgUctTreeStatistics::Compute(), SgUctTree::CopySubtree(), SgUctSearch::FindBestChild(), SgUctSearch::GamesPlayed(), SgUctSearch::GetBound(), SgUctSearch::GetValueEstimate(), SgUctSearch::GetValueEstimateRave(), SgUctTree::MergeChildren(), SgUctSearch::NeedToComputeKnowledge(), SgUctSearch::PlayInTree(), SgUctSearch::PrintSearchProgress(), SgUctSearch::Search(), SgUctSearch::StartSearch(), SgUctSearch::SummaryLine(), and SgUctSearch::WriteStatistics().

int SgUctNode::NuChildren ( ) const

Get number of children.

Note:: This information is an implementation detail of how SgUctTree manages nodes. Use SgUctChildIterator to access children nodes.

Definition at line 430 of file SgUctTree.h.

References m_nuChildren.

Referenced by SgUctTree::ApplyFilter(), SgUctTree::CopySubtree(), SgUctTree::MergeChildren(), SgUctChildIterator::SgUctChildIterator(), and SgUctSearch::StartSearch().

SgUctValue SgUctNode::PosCount ( ) const

Number of times this node was visited.

This corresponds to the sum of MoveCount() of all children. It can be different from MoveCount() of this position, if prior knowledge initialization of the children is used.

Definition at line 435 of file SgUctTree.h.

References m_posCount.

Referenced by SgUctSearch::GetBound(), SgUctTree::MergeChildren(), and SgUctSearch::SelectChild().

SgUctProvenType SgUctNode::ProvenType ( ) const

Definition at line 491 of file SgUctTree.h.

References m_provenType.

SgUctValue SgUctNode::RaveCount ( ) const

Get RAVE count.