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operations_research::LightPairRelocateOperator Class Reference

#include <routing_neighborhoods.h>

Inheritance diagram for operations_research::LightPairRelocateOperator:
operations_research::PathOperator operations_research::IntVarLocalSearchOperator operations_research::LocalSearchOperator operations_research::BaseObject

Public Member Functions

 LightPairRelocateOperator (const std::vector< IntVar * > &vars, const std::vector< IntVar * > &secondary_vars, std::function< int(int64_t)> start_empty_path_class, std::function< const std::vector< int > &(int, int)> get_neighbors, const std::vector< PickupDeliveryPair > &pairs, std::function< bool(int64_t)> force_lifo=nullptr)
 
 LightPairRelocateOperator (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, std::function< bool(int64_t)> force_lifo=nullptr)
 
 ~LightPairRelocateOperator () 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
 
IntVarVar (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 LocalSearchOperatorSelf () 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.
 
BaseObjectoperator= (const BaseObject &)=delete
 
virtual ~BaseObject ()
 

Additional Inherited Members

- Protected Member Functions inherited from operations_research::PathOperator
bool MakeOneNeighbor () override
 This method should not be overridden. Override MakeNeighbor() instead.
 
virtual void OnNodeInitialization ()
 
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 bool RestartAtPathStartOnSynchronize ()
 
virtual bool OnSamePathAsPreviousBase (int64_t base_index)
 
virtual int64_t GetBaseNodeRestartPosition (int base_index)
 
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
 
- Protected Attributes inherited from operations_research::PathOperator
const int number_of_nexts_
 
const bool ignore_path_vars_
 

Detailed Description

Operator which moves a pair of nodes to another position where the first node of the pair must be before the second node on the same path. The default behavior of the operator is to insert the first node after the first node of another pair, and the second node after the other pair's second node. This results in a FIFO behavior. The behavior can be overridden for each path to enforce a LIFO behavior (the second node gets inserted before the other pair's second node). This is specified using the force_lifo callback which takes the start node of a path as argument; if the callback returns true then the LIFO behavior will be enforced, otherwise it's FIFO.

Todo
(user): Add a version which inserts the first node before the other pair's first node; there are many redundant neighbors if done blindly.

Definition at line 283 of file routing_neighborhoods.h.

Constructor & Destructor Documentation

◆ LightPairRelocateOperator() [1/2]

operations_research::LightPairRelocateOperator::LightPairRelocateOperator ( const std::vector< IntVar * > & vars,
const std::vector< IntVar * > & secondary_vars,
std::function< int(int64_t)> start_empty_path_class,
std::function< const std::vector< int > &(int, int)> get_neighbors,
const std::vector< PickupDeliveryPair > & pairs,
std::function< bool(int64_t)> force_lifo = nullptr )

Definition at line 441 of file routing_neighborhoods.cc.

◆ LightPairRelocateOperator() [2/2]

operations_research::LightPairRelocateOperator::LightPairRelocateOperator ( 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,
std::function< bool(int64_t)> force_lifo = nullptr )

Definition at line 457 of file routing_neighborhoods.cc.

◆ ~LightPairRelocateOperator()

operations_research::LightPairRelocateOperator::~LightPairRelocateOperator ( )
inlineoverride

Definition at line 297 of file routing_neighborhoods.h.

Member Function Documentation

◆ DebugString()

std::string operations_research::LightPairRelocateOperator::DebugString ( ) const
inlineoverridevirtual

Reimplemented from operations_research::BaseObject.

Definition at line 300 of file routing_neighborhoods.h.

◆ MakeNeighbor()

bool operations_research::LightPairRelocateOperator::MakeNeighbor ( )
overridevirtual
Note
MoveChain will return false if it is a no-op (moving the chain to its current position). However we want to accept the move if at least node or sibling gets moved to a new position. Therefore we want to be sure both MoveChains are called and at least one succeeds.

Special case handling relocating the first node of a pair "before" the first node of another pair. Limiting this to relocating after the start of the path as other moves will be mostly equivalent to relocating "after".

Todo
(user): extend to relocating before the start of sub-tours (when all pairs have been matched).

Not inserting before a pair node: insert sibling after node.

Depending on the lifo status of the path, insert sibling before or after destination_sibling since node is being inserted before next(destination).

Relocating the first node of a pair "after" the first node of another pair.

Todo
(user): Add support for lifo for neighbor-based move.

Implements operations_research::PathOperator.

Definition at line 466 of file routing_neighborhoods.cc.


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