Detailed Description

This is the base class for building an Lns operator.

An Lns fragment is a collection of variables which will be relaxed. Fragments are built with NextFragment(), which returns false if there are no more fragments to build. Optionally one can override InitFragments, which is called from LocalSearchOperator::Start to initialize fragment data.

Here's a sample relaxing one variable at a time:

class OneVarLns : public BaseLns { public: OneVarLns(const std::vector<IntVar*>& vars) : BaseLns(vars), index_(0) {} virtual ~OneVarLns() {} virtual void InitFragments() { index_ = 0; } virtual bool NextFragment() { const int size = Size(); if (index_ < size) { AppendToFragment(index_); ++index_; return true; } else { return false; } }

private: int index_; };

Definition at line 1260 of file constraint_solveri.h.

Public Member Functions
	BaseLns (const std::vector< IntVar * > &vars)

	~BaseLns () override

virtual void	InitFragments ()

virtual bool	NextFragment ()=0

void	AppendToFragment (int index)

int	FragmentSize () const

bool	HasFragments () const override

bool	MakeNextNeighbor (Assignment delta, Assignment deltadelta) override
	Redefines MakeNextNeighbor to export a simpler interface. More...

bool	HoldsDelta () const override

void	Start (const Assignment *assignment) override
	This method should not be overridden. More...

virtual bool	IsIncremental () const

int	Size () const

const int64_t &	Value (int64_t index) const
	Returns the value in the current assignment of the variable of given index. More...

IntVar *	Var (int64_t index) const
	Returns the variable of given index. More...

virtual bool	SkipUnchanged (int index) const

const int64_t &	OldValue (int64_t index) const

void	SetValue (int64_t index, const 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 incremental)

void	AddVars (const std::vector< IntVar * > &vars)

virtual void	Reset ()

virtual const LocalSearchOperator *	Self () const

virtual std::string	DebugString () const

Protected Member Functions
bool	MakeOneNeighbor () override
	This method should not be overridden. Override NextFragment() instead. More...

bool	IsInverseValue (int64_t index) const

int64_t	InverseValue (int64_t index) const

int64_t	OldInverseValue (int64_t index) const

void	SetInverseValue (int64_t index, int64_t value)

void	SetOldInverseValue (int64_t index, int64_t value)

void	MarkChange (int64_t index)
	OnStart() should really be protected, but then SWIG doesn't see it. More...

Protected Attributes
std::vector< IntVar * >	vars_

std::vector< int64_t >	values_

std::vector< int64_t >	old_values_

std::vector< int64_t >	prev_values_

std::vector< int >	assignment_indices_

Bitset64	activated_

Bitset64	was_activated_

SparseBitset	changes_

SparseBitset	delta_changes_

bool	cleared_

IntVarLocalSearchHandler	var_handler_

Constructor & Destructor Documentation

◆ BaseLns()

BaseLns ( const std::vector< IntVar * > & vars )

explicit

Definition at line 101 of file local_search.cc.

◆ ~BaseLns()

~BaseLns ( )

override

Definition at line 104 of file local_search.cc.

Member Function Documentation

◆ Activate()

void Activate ( int64_t index )

inlineinherited

Definition at line 850 of file constraint_solveri.h.

◆ Activated()

bool Activated ( int64_t index ) const

inlineinherited

Definition at line 849 of file constraint_solveri.h.

◆ AddVars()

void AddVars ( const std::vector< IntVar * > & vars )

inlineinherited

Definition at line 895 of file constraint_solveri.h.

◆ AppendToFragment()

void AppendToFragment ( int index )

Definition at line 121 of file local_search.cc.

◆ ApplyChanges()

bool ApplyChanges	(	Assignment *	delta,
		Assignment *	deltadelta
	)		const

inlineinherited

Definition at line 858 of file constraint_solveri.h.

◆ Deactivate()

void Deactivate ( int64_t index )

inlineinherited

Definition at line 854 of file constraint_solveri.h.

◆ DebugString()

virtual std::string DebugString ( ) const

inlinevirtualinherited

Reimplemented in Trace, LocalSearchMonitorMaster, PropagationBaseObject, Decision, DecisionBuilder, ProfiledDecisionBuilder, Demon, Constraint, IntVarIterator, SolutionCollector, OptimizeVar, SearchLimit, RegularLimit, SequenceVar, Assignment, Pack, CallMethod0< T >, CallMethod1< T, P >, CallMethod2< T, P, Q >, CallMethod3< T, P, Q, R >, DelayedCallMethod0< T >, DelayedCallMethod1< T, P >, DelayedCallMethod2< T, P, Q >, LocalSearchFilterManager, PropagationMonitor, LocalSearchMonitor, BooleanVar, SearchLog, ArrayWithOffset< T >, DemonProfiler, IfThenElseCt, PiecewiseLinearExpr, TwoOpt, Relocate, Exchange, Cross, MakeActiveOperator, RelocateAndMakeActiveOperator, MakeActiveAndRelocate, MakeInactiveOperator, RelocateAndMakeInactiveOperator, MakeChainInactiveOperator, SwapActiveOperator, ExtendedSwapActiveOperator, TSPOpt, TSPLns, LinKernighan, PathLns, NeighborhoodLimit, LocalSearchProfiler, FindOneNeighbor, LocalSearchPhaseParameters, Dimension, GlobalVehicleBreaksConstraint, MakeRelocateNeighborsOperator, MakePairActiveOperator, MakePairInactiveOperator, PairRelocateOperator, LightPairRelocateOperator, PairExchangeOperator, PairExchangeRelocateOperator, SwapIndexPairOperator, IndexPairSwapActiveOperator, FilteredHeuristicPathLNSOperator, RelocatePathAndHeuristicInsertUnperformedOperator, FilteredHeuristicExpensiveChainLNSOperator, FilteredHeuristicCloseNodesLNSOperator, RelocateExpensiveChain, PairNodeSwapActiveOperator< swap_first >, RelocateSubtrip, ExchangeSubtrip, IntVarFilteredDecisionBuilder, and SymmetryManager.

Definition at line 3173 of file constraint_solver.h.

◆ FragmentSize()

int FragmentSize ( ) const

Definition at line 127 of file local_search.cc.

◆ HasFragments()

bool HasFragments ( ) const

inlineoverridevirtual

Reimplemented from LocalSearchOperator.

Definition at line 1268 of file constraint_solveri.h.

◆ HoldsDelta()

bool HoldsDelta ( ) const

inlineoverridevirtualinherited

Reimplemented from LocalSearchOperator.

Definition at line 817 of file constraint_solveri.h.

◆ InitFragments()

void InitFragments ( )

virtual

Definition at line 119 of file local_search.cc.

◆ InverseValue()

int64_t InverseValue ( int64_t index ) const

inlineprotectedinherited

Definition at line 1066 of file constraint_solveri.h.

◆ IsIncremental()

virtual bool IsIncremental ( ) const

inlinevirtualinherited

Reimplemented in TwoOpt.

Definition at line 833 of file constraint_solveri.h.

◆ IsInverseValue()

bool IsInverseValue ( int64_t index ) const

inlineprotectedinherited

Definition at line 1061 of file constraint_solveri.h.

◆ MakeNextNeighbor()

bool MakeNextNeighbor	(	Assignment *	delta,
		Assignment *	deltadelta
	)

overridevirtualinherited

Redefines MakeNextNeighbor to export a simpler interface.

The calls to ApplyChanges() and RevertChanges() are factored in this method, hiding both delta and deltadelta from subclasses which only need to override MakeOneNeighbor(). Therefore this method should not be overridden. Override MakeOneNeighbor() instead.

Implements LocalSearchOperator.

Reimplemented in SwapIndexPairOperator, IndexPairSwapActiveOperator, and PairNodeSwapActiveOperator< swap_first >.

Definition at line 76 of file local_search.cc.

◆ MakeOneNeighbor()

bool MakeOneNeighbor ( )

overrideprotectedvirtual

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

Reimplemented from IntVarLocalSearchOperator.

Definition at line 106 of file local_search.cc.

◆ MarkChange()

void MarkChange ( int64_t index )

inlineprotectedinherited

OnStart() should really be protected, but then SWIG doesn't see it.

So we make it public, but only subclasses should access to it (to override it).

Definition at line 919 of file constraint_solveri.h.

◆ NextFragment()

virtual bool NextFragment ( )

pure virtual

◆ OldInverseValue()

int64_t OldInverseValue ( int64_t index ) const

inlineprotectedinherited

Definition at line 1068 of file constraint_solveri.h.

◆ OldValue()

const int64_t & OldValue ( int64_t index ) const

inlineinherited

Definition at line 844 of file constraint_solveri.h.

◆ Reset()

virtual void Reset ( )

inlinevirtualinherited

Reimplemented in PathOperator.

Definition at line 798 of file constraint_solveri.h.

◆ RevertChanges()

void RevertChanges ( bool incremental )

inlineinherited

Definition at line 882 of file constraint_solveri.h.

◆ Self()

virtual const LocalSearchOperator * Self ( ) const

inlinevirtualinherited

Definition at line 800 of file constraint_solveri.h.

◆ SetInverseValue()

void SetInverseValue	(	int64_t	index,
		int64_t	value
	)

inlineprotectedinherited

Definition at line 1072 of file constraint_solveri.h.

◆ SetOldInverseValue()

void SetOldInverseValue	(	int64_t	index,
		int64_t	value
	)

inlineprotectedinherited

Definition at line 1076 of file constraint_solveri.h.

◆ SetValue()

void SetValue	(	int64_t	index,
		const int64_t &	value
	)

inlineinherited

Definition at line 845 of file constraint_solveri.h.

◆ Size()

int Size ( ) const

inlineinherited

Definition at line 834 of file constraint_solveri.h.

◆ SkipUnchanged()

virtual bool SkipUnchanged ( int index ) const

inlinevirtualinherited

Reimplemented in PathOperator.

Definition at line 843 of file constraint_solveri.h.

◆ Start()

void Start ( const Assignment * assignment )

inlineoverridevirtualinherited

This method should not be overridden.

Override OnStart() instead which is called before exiting this method.

Implements LocalSearchOperator.

Definition at line 820 of file constraint_solveri.h.

◆ Value()

const int64_t & Value ( int64_t index ) const

inlineinherited

Returns the value in the current assignment of the variable of given index.

Definition at line 837 of file constraint_solveri.h.

◆ Var()

IntVar * Var ( int64_t index ) const

inlineinherited

Returns the variable of given index.

Definition at line 842 of file constraint_solveri.h.

Member Data Documentation

◆ activated_

Bitset64 activated_

protectedinherited

Definition at line 929 of file constraint_solveri.h.

◆ assignment_indices_

std::vector<int> assignment_indices_

mutableprotectedinherited

Definition at line 928 of file constraint_solveri.h.

◆ changes_

SparseBitset changes_

protectedinherited

Definition at line 931 of file constraint_solveri.h.

◆ cleared_

bool cleared_

protectedinherited

Definition at line 933 of file constraint_solveri.h.

◆ delta_changes_

SparseBitset delta_changes_

protectedinherited

Definition at line 932 of file constraint_solveri.h.

◆ old_values_

std::vector<int64_t > old_values_

protectedinherited

Definition at line 926 of file constraint_solveri.h.

◆ prev_values_

std::vector<int64_t > prev_values_

protectedinherited

Definition at line 927 of file constraint_solveri.h.

◆ values_

std::vector<int64_t > values_

protectedinherited

Definition at line 925 of file constraint_solveri.h.

◆ var_handler_

IntVarLocalSearchHandler var_handler_

protectedinherited

Definition at line 934 of file constraint_solveri.h.

◆ vars_

std::vector<IntVar *> vars_

protectedinherited

Definition at line 924 of file constraint_solveri.h.

◆ was_activated_

Bitset64 was_activated_

protectedinherited

Definition at line 930 of file constraint_solveri.h.

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

Detailed Description

Public Member Functions

Protected Member Functions

Protected Attributes

Constructor & Destructor Documentation

◆ BaseLns()

◆ ~BaseLns()

Member Function Documentation

◆ Activate()

◆ Activated()

◆ AddVars()

◆ AppendToFragment()

◆ ApplyChanges()

◆ Deactivate()

◆ DebugString()

◆ FragmentSize()

◆ HasFragments()

◆ HoldsDelta()

◆ InitFragments()

◆ InverseValue()

◆ IsIncremental()

◆ IsInverseValue()

◆ MakeNextNeighbor()

◆ MakeOneNeighbor()

◆ MarkChange()

◆ NextFragment()

◆ OldInverseValue()

◆ OldValue()

◆ Reset()

◆ RevertChanges()

◆ Self()

◆ SetInverseValue()

◆ SetOldInverseValue()

◆ SetValue()

◆ Size()

◆ SkipUnchanged()

◆ Start()

◆ Value()

◆ Var()

Member Data Documentation

◆ activated_

◆ assignment_indices_

◆ changes_

◆ cleared_

◆ delta_changes_

◆ old_values_

◆ prev_values_

◆ values_

◆ var_handler_

◆ vars_

◆ was_activated_