#include <routing_neighborhoods.h>

Inheritance diagram for operations_research::MakePairActiveOperator:

Public Member Functions
	MakePairActiveOperator (const std::vector< IntVar * > &vars, const std::vector< IntVar * > &secondary_vars, std::function< int(int64_t)> start_empty_path_class, const std::vector< PickupDeliveryPair > &pairs)

	~MakePairActiveOperator () override

bool	MakeNeighbor () override

std::string	DebugString () const override

Public Member Functions inherited from operations_research::PathOperator
	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_neighbors)

	~PathOperator () 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 ()

Protected Member Functions
bool	MakeOneNeighbor () override

bool	OnSamePathAsPreviousBase (int64_t) override

int64_t	GetBaseNodeRestartPosition (int base_index) override

bool	RestartAtPathStartOnSynchronize () override

Protected Member Functions inherited from operations_research::PathOperator
bool	MakeOneNeighbor () override
	This method should not be overridden. Override MakeNeighbor() instead.

int64_t	BaseNode (int i) const
	Returns the ith base node of the operator.

int	BaseAlternative (int i) const
	Returns the alternative for the ith base node.

int64_t	BaseAlternativeNode (int i) const
	Returns the alternative node for the ith base node.

int	BaseSiblingAlternative (int i) const
	Returns the alternative for the sibling of 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 void	SetNextBaseToIncrement (int64_t base_index)

virtual bool	ConsiderAlternatives (int64_t base_index) 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	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.

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.

int64_t	GetActiveAlternativeSibling (int node) const

bool	CheckChainValidity (int64_t before_chain, int64_t chain_end, int64_t exclude) const

bool	HasNeighbors () const

int	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

Additional Inherited Members
Protected Attributes inherited from operations_research::PathOperator
const int	number_of_nexts_

const bool	ignore_path_vars_

Detailed Description

Pair-based neighborhood operators, designed to move nodes by pairs (pairs are static and given). These neighborhoods are very useful for Pickup and Delivery problems where pickup and delivery nodes must remain on the same route.

Todo

(user): Add option to prune neighbords where the order of node pairs is violated (ie precedence between pickup and delivery nodes).

(user): Move this to local_search.cc if it's generic enough.

(user): Detect pairs automatically by parsing the constraint model; we could then get rid of the pair API in the RoutingModel class.

Operator which inserts pairs of inactive nodes into a path. Possible neighbors for the path 1 -> 2 -> 3 with pair (A, B) inactive (where 1 and 3 are first and last nodes of the path) are: 1 -> [A] -> [B] -> 2 -> 3 1 -> [B] -> 2 -> [A] -> 3 1 -> [A] -> 2 -> [B] -> 3 1 -> 2 -> [A] -> [B] -> 3

Note: this operator does not explicitly insert the nodes of a pair one after the other which forbids the following solutions: 1 -> [B] -> [A] -> 2 -> 3 1 -> 2 -> [B] -> [A] -> 3 which can only be obtained by inserting A after B.

Definition at line 163 of file routing_neighborhoods.h.

Constructor & Destructor Documentation

◆ MakePairActiveOperator()

operations_research::MakePairActiveOperator::MakePairActiveOperator	(	const std::vector< IntVar * > &	vars,
		const std::vector< IntVar * > &	secondary_vars,
		std::function< int(int64_t)>	start_empty_path_class,
		const std::vector< PickupDeliveryPair > &	pairs )

Definition at line 240 of file routing_neighborhoods.cc.

◆ ~MakePairActiveOperator()

operations_research::MakePairActiveOperator::~MakePairActiveOperator ( )

inlineoverride

Definition at line 169 of file routing_neighborhoods.h.

Member Function Documentation

◆ DebugString()

std::string operations_research::MakePairActiveOperator::DebugString ( ) const

inlineoverridevirtual

Reimplemented from operations_research::BaseObject.

Definition at line 171 of file routing_neighborhoods.h.

◆ GetBaseNodeRestartPosition()

int64_t operations_research::MakePairActiveOperator::GetBaseNodeRestartPosition ( int base_index )

overrideprotectedvirtual

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.

Base node 1 must be after base node 0 if they are both on the same path.

Reimplemented from operations_research::PathOperator.

Definition at line 287 of file routing_neighborhoods.cc.

◆ MakeNeighbor()

bool operations_research::MakePairActiveOperator::MakeNeighbor ( )

overridevirtual

Inserting the second node of the pair before the first one which ensures that the only solutions where both nodes are next to each other have the first node before the second (the move is not symmetric and doing it this way ensures that a potential precedence constraint between the nodes of the pair is not violated).

Implements operations_research::PathOperator.

Definition at line 272 of file routing_neighborhoods.cc.

◆ MakeOneNeighbor()

bool operations_research::MakePairActiveOperator::MakeOneNeighbor ( )

overrideprotectedvirtual

Creates a new neighbor. It returns false when the neighborhood is completely explored.

Todo: (user): make it pure virtual, implies porting all apps overriding MakeNextNeighbor() in a subclass of IntVarLocalSearchOperator.

Todo: (user): Make this a pure virtual.

Reimplemented from operations_research::IntVarLocalSearchOperator.

Definition at line 252 of file routing_neighborhoods.cc.

◆ OnSamePathAsPreviousBase()

bool operations_research::MakePairActiveOperator::OnSamePathAsPreviousBase ( int64_t base_index )

inlineoverrideprotectedvirtual

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.

Both base nodes have to be on the same path since they represent the nodes after which unactive node pairs will be moved.

Reimplemented from operations_research::PathOperator.

Definition at line 175 of file routing_neighborhoods.h.

◆ RestartAtPathStartOnSynchronize()

bool operations_research::MakePairActiveOperator::RestartAtPathStartOnSynchronize ( )

inlineoverrideprotectedvirtual

Required to ensure that after synchronization the operator is in a state compatible with GetBaseNodeRestartPosition.

Reimplemented from operations_research::PathOperator.

Definition at line 185 of file routing_neighborhoods.h.

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

ortools/constraint_solver/routing_neighborhoods.h
ortools/constraint_solver/routing_neighborhoods.cc

Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ MakePairActiveOperator()

◆ ~MakePairActiveOperator()

Member Function Documentation

◆ DebugString()

◆ GetBaseNodeRestartPosition()

◆ MakeNeighbor()

◆ MakeOneNeighbor()

◆ OnSamePathAsPreviousBase()

◆ RestartAtPathStartOnSynchronize()