operations_research::PathOperator< ignore_path_vars > Class Template Reference

Detailed Description

template<bool ignore_path_vars>
class operations_research::PathOperator< ignore_path_vars >

Base class of the local search operators dedicated to path modifications (a path is a set of nodes linked together by arcs). This family of neighborhoods supposes they are handling next variables representing the arcs (var[i] represents the node immediately after i on a path). Several services are provided:

• arc manipulators (SetNext(), ReverseChain(), MoveChain())
• path inspectors (Next(), Prev(), IsPathEnd())
• path iterators: operators need a given number of nodes to define a neighbor; this class provides the iteration on a given number of (base) nodes which can be used to define a neighbor (through the BaseNode method) Subclasses only need to override MakeNeighbor to create neighbors using the services above (no direct manipulation of assignments).

Definition at line 1531 of file constraint_solveri.h.

#include <constraint_solveri.h>

Inheritance diagram for operations_research::PathOperator< ignore_path_vars >:

Classes
struct	IterationParameters
	Set of parameters used to configure how the neighborhood is traversed. More...
struct	Neighbor

Public Member Functions
	PathOperator (const std::vector< IntVar * > &next_vars, const std::vector< IntVar * > &path_vars, IterationParameters iteration_parameters)
	Builds an instance of PathOperator from next and path variables.
	PathOperator (const std::vector< IntVar * > &next_vars, const std::vector< IntVar * > &path_vars, int number_of_base_nodes, bool skip_locally_optimal_paths, bool accept_path_end_base, std::function< int(int64_t)> start_empty_path_class, std::function< const std::vector< int > &(int, int)> get_incoming_neighbors, std::function< const std::vector< int > &(int, int)> get_outgoing_neighbors)
	~PathOperator () override
virtual bool	MakeNeighbor ()=0
void	EnterSearch () override
void	Reset () override
bool	SkipUnchanged (int index) const override
int64_t	Next (int64_t node) const
	Returns the node after node in the current delta.
int64_t	Prev (int64_t node) const
	Returns the node before node in the current delta.
int64_t	Path (int64_t node) const
int	number_of_nexts () const
	Number of next variables.
Public Member Functions inherited from operations_research::IntVarLocalSearchOperator
	IntVarLocalSearchOperator (const std::vector< IntVar * > &vars, bool keep_inverse_values=false)
	~IntVarLocalSearchOperator () override
bool	HoldsDelta () const override
void	Start (const Assignment *assignment) override
virtual bool	IsIncremental () const
int	Size () const
int64_t	Value (int64_t index) const
IntVar *	Var (int64_t index) const
	Returns the variable of given index.
int64_t	OldValue (int64_t index) const
int64_t	PrevValue (int64_t index) const
void	SetValue (int64_t index, int64_t value)
bool	Activated (int64_t index) const
void	Activate (int64_t index)
void	Deactivate (int64_t index)
bool	ApplyChanges (Assignment *delta, Assignment *deltadelta) const
void	RevertChanges (bool change_was_incremental)
void	AddVars (const std::vector< IntVar * > &vars)
bool	MakeNextNeighbor (Assignment *delta, Assignment *deltadelta) override
	--— Base operator class for operators manipulating IntVars --—
Public Member Functions inherited from operations_research::LocalSearchOperator
	LocalSearchOperator ()
	~LocalSearchOperator () override
virtual const LocalSearchOperator *	Self () const
virtual bool	HasFragments () const
Public Member Functions inherited from operations_research::BaseObject
	BaseObject ()
	BaseObject (const BaseObject &)=delete
	This type is neither copyable nor movable.
BaseObject &	operator= (const BaseObject &)=delete
virtual	~BaseObject ()=default
virtual std::string	DebugString () const

Protected Member Functions
bool	MakeOneNeighbor () override
	This method should not be overridden. Override MakeNeighbor() instead.
virtual void	OnNodeInitialization ()
virtual void	ResetIncrementalism ()
int64_t	BaseNode (int i) const
	Returns the ith base node of the operator.
int64_t	BaseAlternativeNode (int i) const
	Returns the alternative node for the ith base node.
int64_t	BaseSiblingAlternativeNode (int i) const
	Returns the alternative node for the sibling of the ith base node.
int64_t	StartNode (int i) const
	Returns the start node of the ith base node.
int64_t	EndNode (int i) const
	Returns the end node of the ith base node.
const std::vector< int64_t > &	path_starts () const
	Returns the vector of path start nodes.
int	PathClass (int i) const
	Returns the class of the path of the ith base node.
int	PathClassFromStartNode (int64_t start_node) const
virtual bool	RestartAtPathStartOnSynchronize ()
virtual bool	OnSamePathAsPreviousBase (int64_t)
virtual int64_t	GetBaseNodeRestartPosition (int base_index)
virtual void	SetNextBaseToIncrement (int64_t base_index)
virtual bool	ConsiderAlternatives (int64_t) const
int64_t	OldNext (int64_t node) const
int64_t	PrevNext (int64_t node) const
int64_t	OldPrev (int64_t node) const
int64_t	OldPath (int64_t node) const
int	CurrentNodePathStart (int64_t node) const
int	CurrentNodePathEnd (int64_t node) const
bool	MoveChain (int64_t before_chain, int64_t chain_end, int64_t destination)
bool	ReverseChain (int64_t before_chain, int64_t after_chain, int64_t *chain_last)
bool	SwapNodes (int64_t node1, int64_t node2)
	Swaps the nodes node1 and node2.
bool	MakeActive (int64_t node, int64_t destination)
	Insert the inactive node after destination.
bool	MakeChainInactive (int64_t before_chain, int64_t chain_end)
bool	SwapActiveAndInactive (int64_t active, int64_t inactive)
	Replaces active by inactive in the current path, making active inactive.
bool	SwapActiveAndInactiveChains (absl::Span< const int64_t > active_chain, absl::Span< const int64_t > inactive_chain)
void	SetNext (int64_t from, int64_t to, int64_t path)
	Sets 'to' to be the node after 'from' on the given path.
bool	IsPathEnd (int64_t node) const
bool	IsPathStart (int64_t node) const
	Returns true if node is the first node on the path.
bool	IsInactive (int64_t node) const
	Returns true if node is inactive.
virtual bool	InitPosition () const
void	ResetPosition ()
int	AddAlternativeSet (const std::vector< int64_t > &alternative_set)
template<typename PairType>
void	AddPairAlternativeSets (const std::vector< PairType > &pair_alternative_sets)
int64_t	GetActiveInAlternativeSet (int alternative_index) const
	Returns the active node in the given alternative set.
int64_t	GetActiveAlternativeNode (int node) const
	Returns the active node in the alternative set of the given node.
int	GetSiblingAlternativeIndex (int node) const
	Returns the index of the alternative set of the sibling of node.
int	GetAlternativeIndex (int node) const
	Returns the index of the alternative set of the node.
int64_t	GetActiveAlternativeSibling (int node) const
bool	CheckChainValidity (int64_t before_chain, int64_t chain_end, int64_t exclude) const
bool	HasNeighbors () const
Neighbor	GetNeighborForBaseNode (int64_t base_index) const
Protected Member Functions inherited from operations_research::IntVarLocalSearchOperator
int64_t	InverseValue (int64_t index) const
int64_t	OldInverseValue (int64_t index) const
void	AddToAssignment (IntVar *var, int64_t value, bool active, std::vector< int > *assignment_indices, int64_t index, Assignment *assignment) const

Protected Attributes
const int	number_of_nexts_

Friends
class	BaseNodeIterators< PathOperator >
class	AlternativeNodeIterator
class	NodeNeighborIterator

Constructor & Destructor Documentation

PathOperator() [1/2]

template<bool ignore_path_vars>

operations_research::PathOperator< ignore_path_vars >::PathOperator ( const std::vector< IntVar * > & next_vars, const std::vector< IntVar * > & path_vars, IterationParameters iteration_parameters )

inline

Builds an instance of PathOperator from next and path variables.

Definition at line 1563 of file constraint_solveri.h.

PathOperator() [2/2]

template<bool ignore_path_vars>

operations_research::PathOperator< ignore_path_vars >::PathOperator ( const std::vector< IntVar * > & next_vars, const std::vector< IntVar * > & path_vars, int number_of_base_nodes, bool skip_locally_optimal_paths, bool accept_path_end_base, std::function< int(int64_t)> start_empty_path_class, std::function< const std::vector< int > &(int, int)> get_incoming_neighbors, std::function< const std::vector< int > &(int, int)> get_outgoing_neighbors )

inline

Definition at line 1602 of file constraint_solveri.h.

~PathOperator()

template<bool ignore_path_vars>

operations_research::PathOperator< ignore_path_vars >::~PathOperator ( )

inlineoverride

Definition at line 1614 of file constraint_solveri.h.

Member Function Documentation

AddAlternativeSet()

template<bool ignore_path_vars>

int operations_research::PathOperator< ignore_path_vars >::AddAlternativeSet ( const std::vector< int64_t > & alternative_set )

inlineprotected

Handling node alternatives. Adds a set of node alternatives to the neighborhood. No node can be in two alternatives.

Definition at line 1911 of file constraint_solveri.h.

AddPairAlternativeSets()

template<bool ignore_path_vars>

template<typename PairType>

void operations_research::PathOperator< ignore_path_vars >::AddPairAlternativeSets ( const std::vector< PairType > & pair_alternative_sets )

inlineprotected

Adds all sets of node alternatives of a vector of alternative pairs. No node can be in two alternatives.

Definition at line 1925 of file constraint_solveri.h.

BaseAlternativeNode()

template<bool ignore_path_vars>

int64_t operations_research::PathOperator< ignore_path_vars >::BaseAlternativeNode ( int i ) const

inlineprotected

Returns the alternative node for the ith base node.

Definition at line 1686 of file constraint_solveri.h.

BaseNode()

template<bool ignore_path_vars>

int64_t operations_research::PathOperator< ignore_path_vars >::BaseNode ( int i ) const

inlineprotected

Returns the ith base node of the operator.

Definition at line 1684 of file constraint_solveri.h.

BaseSiblingAlternativeNode()

template<bool ignore_path_vars>

int64_t operations_research::PathOperator< ignore_path_vars >::BaseSiblingAlternativeNode ( int i ) const

inlineprotected

Returns the alternative node for the sibling of the ith base node.

Definition at line 1691 of file constraint_solveri.h.

CheckChainValidity()

template<bool ignore_path_vars>

bool operations_research::PathOperator< ignore_path_vars >::CheckChainValidity ( int64_t before_chain, int64_t chain_end, int64_t exclude ) const

inlineprotected

Returns true if the chain is a valid path without cycles from before_chain to chain_end and does not contain exclude. In particular, rejects a chain if chain_end is not strictly after before_chain on the path. Cycles are detected through chain length overflow.

Definition at line 1963 of file constraint_solveri.h.

ConsiderAlternatives()

template<bool ignore_path_vars>

virtual bool operations_research::PathOperator< ignore_path_vars >::ConsiderAlternatives ( int64_t ) const

inlineprotectedvirtual

Indicates if alternatives should be considered when iterating over base nodes.

Reimplemented in operations_research::PairRelocateOperator< ignore_path_vars >.

Definition at line 1739 of file constraint_solveri.h.

CurrentNodePathEnd()

template<bool ignore_path_vars>

int operations_research::PathOperator< ignore_path_vars >::CurrentNodePathEnd ( int64_t node ) const

inlineprotected

Definition at line 1765 of file constraint_solveri.h.

CurrentNodePathStart()

template<bool ignore_path_vars>

int operations_research::PathOperator< ignore_path_vars >::CurrentNodePathStart ( int64_t node ) const

inlineprotected

Definition at line 1761 of file constraint_solveri.h.

EndNode()

template<bool ignore_path_vars>

int64_t operations_research::PathOperator< ignore_path_vars >::EndNode ( int i ) const

inlineprotected

Returns the end node of the ith base node.

Definition at line 1698 of file constraint_solveri.h.

EnterSearch()

template<bool ignore_path_vars>

void operations_research::PathOperator< ignore_path_vars >::EnterSearch ( )

inlineoverridevirtual

Reimplemented from operations_research::LocalSearchOperator.

Definition at line 1616 of file constraint_solveri.h.

GetActiveAlternativeNode()

template<bool ignore_path_vars>

int64_t operations_research::PathOperator< ignore_path_vars >::GetActiveAlternativeNode ( int node ) const

inlineprotected

Returns the active node in the alternative set of the given node.

Definition at line 1941 of file constraint_solveri.h.

GetActiveAlternativeSibling()

template<bool ignore_path_vars>

int64_t operations_research::PathOperator< ignore_path_vars >::GetActiveAlternativeSibling ( int node ) const

inlineprotected

Returns the active node in the alternative set of the sibling of the given node.

Definition at line 1955 of file constraint_solveri.h.

GetActiveInAlternativeSet()

template<bool ignore_path_vars>

int64_t operations_research::PathOperator< ignore_path_vars >::GetActiveInAlternativeSet ( int alternative_index ) const

inlineprotected

Returns the active node in the given alternative set.

Definition at line 1935 of file constraint_solveri.h.

GetAlternativeIndex()

template<bool ignore_path_vars>

int operations_research::PathOperator< ignore_path_vars >::GetAlternativeIndex ( int node ) const

inlineprotected

Returns the index of the alternative set of the node.

Definition at line 1950 of file constraint_solveri.h.

GetBaseNodeRestartPosition()

template<bool ignore_path_vars>

virtual int64_t operations_research::PathOperator< ignore_path_vars >::GetBaseNodeRestartPosition ( int base_index )

inlineprotectedvirtual

Returns the index of the node to which the base node of index base_index must be set to when it reaches the end of a path. By default, it is set to the start of the current path. When this method is called, one can only assume that base nodes with indices < base_index have their final position.

Reimplemented in operations_research::ExchangePathStartEndsAndMakeActiveOperator< ignore_path_vars >, operations_research::MakeChainInactiveOperator< ignore_path_vars >, operations_research::MakePairActiveOperator< ignore_path_vars >, operations_research::PairExchangeRelocateOperator< ignore_path_vars >, operations_research::PairNodeSwapActiveOperator< swap_first, ignore_path_vars >, operations_research::PairRelocateOperator< ignore_path_vars >, operations_research::TwoOpt< ignore_path_vars >, and operations_research::TwoOptWithShortestPathOperator< ignore_path_vars >.

Definition at line 1729 of file constraint_solveri.h.

GetNeighborForBaseNode()

template<bool ignore_path_vars>

Neighbor operations_research::PathOperator< ignore_path_vars >::GetNeighborForBaseNode ( int64_t base_index ) const

inlineprotected

Definition at line 1990 of file constraint_solveri.h.

GetSiblingAlternativeIndex()

template<bool ignore_path_vars>

int operations_research::PathOperator< ignore_path_vars >::GetSiblingAlternativeIndex ( int node ) const

inlineprotected

Returns the index of the alternative set of the sibling of node.

Definition at line 1945 of file constraint_solveri.h.

HasNeighbors()

template<bool ignore_path_vars>

bool operations_research::PathOperator< ignore_path_vars >::HasNeighbors ( ) const

inlineprotected

Definition at line 1978 of file constraint_solveri.h.

InitPosition()

template<bool ignore_path_vars>

virtual bool operations_research::PathOperator< ignore_path_vars >::InitPosition ( ) const

inlineprotectedvirtual

Returns true if the operator needs to restart its initial position at each call to Start()

Definition at line 1902 of file constraint_solveri.h.

IsInactive()

template<bool ignore_path_vars>

bool operations_research::PathOperator< ignore_path_vars >::IsInactive ( int64_t node ) const

inlineprotected

Returns true if node is inactive.

Definition at line 1896 of file constraint_solveri.h.

IsPathEnd()

template<bool ignore_path_vars>

bool operations_research::PathOperator< ignore_path_vars >::IsPathEnd ( int64_t node ) const

inlineprotected

Returns true if node is the last node on the path; defined by the fact that node is outside the range of the variable array.

Definition at line 1890 of file constraint_solveri.h.

IsPathStart()

template<bool ignore_path_vars>

bool operations_research::PathOperator< ignore_path_vars >::IsPathStart ( int64_t node ) const

inlineprotected

Returns true if node is the first node on the path.

Definition at line 1893 of file constraint_solveri.h.

MakeActive()

template<bool ignore_path_vars>

bool operations_research::PathOperator< ignore_path_vars >::MakeActive ( int64_t node, int64_t destination )

inlineprotected

Insert the inactive node after destination.

Definition at line 1829 of file constraint_solveri.h.

MakeChainInactive()

template<bool ignore_path_vars>

bool operations_research::PathOperator< ignore_path_vars >::MakeChainInactive ( int64_t before_chain, int64_t chain_end )

inlineprotected

Makes the nodes on the chain starting after before_chain and ending at chain_end inactive.

Definition at line 1838 of file constraint_solveri.h.

MakeNeighbor()

template<bool ignore_path_vars>

virtual bool operations_research::PathOperator< ignore_path_vars >::MakeNeighbor ( )

pure virtual

Implemented in operations_research::Cross< ignore_path_vars >, operations_research::Exchange< ignore_path_vars >, operations_research::ExchangeAndMakeActiveOperator< ignore_path_vars >, operations_research::ExchangePathStartEndsAndMakeActiveOperator< ignore_path_vars >, operations_research::ExchangeSubtrip< ignore_path_vars >, operations_research::ExtendedSwapActiveOperator< ignore_path_vars >, operations_research::GroupPairAndRelocateOperator< ignore_path_vars >, operations_research::IndexPairSwapActiveOperator< ignore_path_vars >, operations_research::LightPairRelocateOperator< ignore_path_vars >, operations_research::LinKernighan< ignore_path_vars >, operations_research::MakeActiveAndRelocateOperator< ignore_path_vars >, operations_research::MakeActiveOperator< ignore_path_vars >, operations_research::MakeChainInactiveOperator< ignore_path_vars >, operations_research::MakeInactiveOperator< ignore_path_vars >, operations_research::MakePairActiveOperator< ignore_path_vars >, operations_research::MakePairInactiveOperator< ignore_path_vars >, operations_research::MakeRelocateNeighborsOperator< ignore_path_vars >, operations_research::PairExchangeOperator< ignore_path_vars >, operations_research::PairExchangeRelocateOperator< ignore_path_vars >, operations_research::PairNodeSwapActiveOperator< swap_first, ignore_path_vars >, operations_research::PairRelocateOperator< ignore_path_vars >, operations_research::PathLns< ignore_path_vars >, operations_research::Relocate< ignore_path_vars >, operations_research::RelocateAndMakeActiveOperator< ignore_path_vars >, operations_research::RelocateAndMakeInactiveOperator< ignore_path_vars >, operations_research::RelocateExpensiveChain< ignore_path_vars >, operations_research::RelocateSubtrip< ignore_path_vars >, operations_research::SwapActiveChainOperator< ignore_path_vars >, operations_research::SwapActiveOperator< ignore_path_vars >, operations_research::SwapActiveToShortestPathOperator< ignore_path_vars >, operations_research::TSPLns< ignore_path_vars >, operations_research::TSPOpt< ignore_path_vars >, operations_research::TwoOpt< ignore_path_vars >, and operations_research::TwoOptWithShortestPathOperator< ignore_path_vars >.

MakeOneNeighbor()

template<bool ignore_path_vars>

bool operations_research::PathOperator< ignore_path_vars >::MakeOneNeighbor ( )

inlineoverrideprotectedvirtual

This method should not be overridden. Override MakeNeighbor() instead.

Need to revert changes here since MakeNeighbor might have returned false and have done changes in the previous iteration.

Reimplemented from operations_research::IntVarLocalSearchOperator.

Reimplemented in operations_research::RelocateExpensiveChain< ignore_path_vars >, and operations_research::TSPLns< ignore_path_vars >.

Definition at line 1661 of file constraint_solveri.h.

MoveChain()

template<bool ignore_path_vars>

bool operations_research::PathOperator< ignore_path_vars >::MoveChain ( int64_t before_chain, int64_t chain_end, int64_t destination )

inlineprotected

Moves the chain starting after the node before_chain and ending at the node chain_end after the node destination

Definition at line 1769 of file constraint_solveri.h.

Next()

template<bool ignore_path_vars>

int64_t operations_research::PathOperator< ignore_path_vars >::Next ( int64_t node ) const

inline

Returns the node after node in the current delta.

Definition at line 1637 of file constraint_solveri.h.

number_of_nexts()

template<bool ignore_path_vars>

int operations_research::PathOperator< ignore_path_vars >::number_of_nexts ( ) const

inline

Number of next variables.

Definition at line 1657 of file constraint_solveri.h.

OldNext()

template<bool ignore_path_vars>

int64_t operations_research::PathOperator< ignore_path_vars >::OldNext ( int64_t node ) const

inlineprotected

Definition at line 1741 of file constraint_solveri.h.

OldPath()

template<bool ignore_path_vars>

int64_t operations_research::PathOperator< ignore_path_vars >::OldPath ( int64_t node ) const

inlineprotected

Definition at line 1756 of file constraint_solveri.h.

OldPrev()

template<bool ignore_path_vars>

int64_t operations_research::PathOperator< ignore_path_vars >::OldPrev ( int64_t node ) const

inlineprotected

Definition at line 1751 of file constraint_solveri.h.

OnNodeInitialization()

template<bool ignore_path_vars>

virtual void operations_research::PathOperator< ignore_path_vars >::OnNodeInitialization ( )

inlineprotectedvirtual

Called by OnStart() after initializing node information. Should be overridden instead of OnStart() to avoid calling PathOperator::OnStart explicitly.

Definition at line 1676 of file constraint_solveri.h.

OnSamePathAsPreviousBase()

template<bool ignore_path_vars>

virtual bool operations_research::PathOperator< ignore_path_vars >::OnSamePathAsPreviousBase ( int64_t )

inlineprotectedvirtual

Returns true if a base node has to be on the same path as the "previous" base node (base node of index base_index - 1). Useful to limit neighborhood exploration to nodes on the same path.

Todo

(user): ideally this should be OnSamePath(int64_t node1, int64_t node2); it's currently way more complicated to implement.

Reimplemented in operations_research::ExchangeAndMakeActiveOperator< ignore_path_vars >, operations_research::MakeChainInactiveOperator< ignore_path_vars >, operations_research::MakePairActiveOperator< ignore_path_vars >, operations_research::PairExchangeRelocateOperator< ignore_path_vars >, operations_research::PairNodeSwapActiveOperator< swap_first, ignore_path_vars >, operations_research::PairRelocateOperator< ignore_path_vars >, operations_research::Relocate< ignore_path_vars >, operations_research::SwapActiveChainOperator< ignore_path_vars >, operations_research::TwoOpt< ignore_path_vars >, and operations_research::TwoOptWithShortestPathOperator< ignore_path_vars >.

Definition at line 1723 of file constraint_solveri.h.

Path()

template<bool ignore_path_vars>

int64_t operations_research::PathOperator< ignore_path_vars >::Path ( int64_t node ) const

inline

Returns the index of the path to which node belongs in the current delta. Only returns a valid value if path variables are taken into account.

Definition at line 1651 of file constraint_solveri.h.

path_starts()

template<bool ignore_path_vars>

const std::vector< int64_t > & operations_research::PathOperator< ignore_path_vars >::path_starts ( ) const

inlineprotected

Returns the vector of path start nodes.

Definition at line 1700 of file constraint_solveri.h.

PathClass()

template<bool ignore_path_vars>

int operations_research::PathOperator< ignore_path_vars >::PathClass ( int i ) const

inlineprotected

Returns the class of the path of the ith base node.

Definition at line 1702 of file constraint_solveri.h.

PathClassFromStartNode()

template<bool ignore_path_vars>

int operations_research::PathOperator< ignore_path_vars >::PathClassFromStartNode ( int64_t start_node ) const

inlineprotected

Definition at line 1703 of file constraint_solveri.h.

Prev()

template<bool ignore_path_vars>

int64_t operations_research::PathOperator< ignore_path_vars >::Prev ( int64_t node ) const

inline

Returns the node before node in the current delta.

Definition at line 1643 of file constraint_solveri.h.

PrevNext()

template<bool ignore_path_vars>

int64_t operations_research::PathOperator< ignore_path_vars >::PrevNext ( int64_t node ) const

inlineprotected

Definition at line 1746 of file constraint_solveri.h.

Reset()

template<bool ignore_path_vars>

void operations_research::PathOperator< ignore_path_vars >::Reset ( )

inlineoverridevirtual

Reimplemented from operations_research::LocalSearchOperator.

Definition at line 1620 of file constraint_solveri.h.

ResetIncrementalism()

template<bool ignore_path_vars>

virtual void operations_research::PathOperator< ignore_path_vars >::ResetIncrementalism ( )

inlineprotectedvirtual

When entering a new search or using metaheuristics, path operators reactivate optimal routes and iterating re-starts at route starts, which can potentially be out of sync with the last incremental moves. This requires resetting incrementalism.

Reimplemented in operations_research::SwapActiveChainOperator< ignore_path_vars >, and operations_research::TwoOpt< ignore_path_vars >.

Definition at line 1681 of file constraint_solveri.h.

ResetPosition()

template<bool ignore_path_vars>

void operations_research::PathOperator< ignore_path_vars >::ResetPosition ( )

inlineprotected

Reset the position of the operator to its position when Start() was last called; this can be used to let an operator iterate more than once over the paths.

Definition at line 1906 of file constraint_solveri.h.

RestartAtPathStartOnSynchronize()

template<bool ignore_path_vars>

virtual bool operations_research::PathOperator< ignore_path_vars >::RestartAtPathStartOnSynchronize ( )

inlineprotectedvirtual

When the operator is being synchronized with a new solution (when Start() is called), returns true to restart the exploration of the neighborhood from the start of the last paths explored; returns false to restart the exploration at the last nodes visited. This is used to avoid restarting on base nodes which have changed paths, leading to potentially skipping neighbors.

Todo

(user): remove this when automatic detection of such cases in done.

Reimplemented in operations_research::MakePairActiveOperator< ignore_path_vars >, operations_research::PairNodeSwapActiveOperator< swap_first, ignore_path_vars >, and operations_research::TwoOptWithShortestPathOperator< ignore_path_vars >.

Definition at line 1716 of file constraint_solveri.h.

ReverseChain()

template<bool ignore_path_vars>

bool operations_research::PathOperator< ignore_path_vars >::ReverseChain ( int64_t before_chain, int64_t after_chain, int64_t * chain_last )

inlineprotected

Reverses the chain starting after before_chain and ending before after_chain

Definition at line 1793 of file constraint_solveri.h.

SetNext()

template<bool ignore_path_vars>

void operations_research::PathOperator< ignore_path_vars >::SetNext ( int64_t from, int64_t to, int64_t path )

inlineprotected

Sets 'to' to be the node after 'from' on the given path.

Definition at line 1879 of file constraint_solveri.h.

SetNextBaseToIncrement()

template<bool ignore_path_vars>

virtual void operations_research::PathOperator< ignore_path_vars >::SetNextBaseToIncrement ( int64_t base_index )

inlineprotectedvirtual

Set the next base to increment on next iteration. All base > base_index will be reset to their start value.

Definition at line 1734 of file constraint_solveri.h.

SkipUnchanged()

template<bool ignore_path_vars>

bool operations_research::PathOperator< ignore_path_vars >::SkipUnchanged ( int index ) const

inlineoverridevirtual

Todo

(user): Make the following methods protected.

Reimplemented from operations_research::IntVarLocalSearchOperator.

Definition at line 1626 of file constraint_solveri.h.

StartNode()

template<bool ignore_path_vars>

int64_t operations_research::PathOperator< ignore_path_vars >::StartNode ( int i ) const

inlineprotected

Returns the start node of the ith base node.

Definition at line 1696 of file constraint_solveri.h.

SwapActiveAndInactive()

template<bool ignore_path_vars>

bool operations_research::PathOperator< ignore_path_vars >::SwapActiveAndInactive ( int64_t active, int64_t inactive )

inlineprotected

Replaces active by inactive in the current path, making active inactive.

Definition at line 1856 of file constraint_solveri.h.

SwapActiveAndInactiveChains()

template<bool ignore_path_vars>

bool operations_research::PathOperator< ignore_path_vars >::SwapActiveAndInactiveChains ( absl::Span< const int64_t > active_chain, absl::Span< const int64_t > inactive_chain )

inlineprotected

Swaps both chains, making nodes on active_chain inactive and inserting active_chain at the position where inactive_chain was.

Definition at line 1863 of file constraint_solveri.h.

SwapNodes()

template<bool ignore_path_vars>

bool operations_research::PathOperator< ignore_path_vars >::SwapNodes ( int64_t node1, int64_t node2 )

inlineprotected

Swaps the nodes node1 and node2.

Definition at line 1817 of file constraint_solveri.h.

Friends And Related Symbol Documentation

AlternativeNodeIterator

template<bool ignore_path_vars>

friend class AlternativeNodeIterator

friend

Definition at line 2427 of file constraint_solveri.h.

BaseNodeIterators< PathOperator >

template<bool ignore_path_vars>

friend class BaseNodeIterators< PathOperator >

friend

Definition at line 2424 of file constraint_solveri.h.

NodeNeighborIterator

template<bool ignore_path_vars>

friend class NodeNeighborIterator

friend

Definition at line 2428 of file constraint_solveri.h.

Member Data Documentation

number_of_nexts_

template<bool ignore_path_vars>

const int operations_research::PathOperator< ignore_path_vars >::number_of_nexts_

protected

Definition at line 1996 of file constraint_solveri.h.

---

The documentation for this class was generated from the following file:

• ortools/constraint_solver/constraint_solveri.h