C++ Reference
C++ Reference: Routing
Detailed Description
The following constraint ensures that incompatibilities and requirements between types are respected.
It verifies both "hard" and "temporal" incompatibilities. Two nodes with hard incompatible types cannot be served by the same vehicle at all, while with a temporal incompatibility they can't be on the same route at the same time. The VisitTypePolicy of a node determines how visiting it impacts the type count on the route.
For example, for
- three temporally incompatible types T1 T2 and T3
- 2 pairs of nodes a1/r1 and a2/r2 of type T1 and T2 respectively, with
- a1 and a2 of VisitTypePolicy TYPE_ADDED_TO_VEHICLE
- r1 and r2 of policy ADDED_TYPE_REMOVED_FROM_VEHICLE
- 3 nodes A, UV and AR of type T3, respectively with type policies TYPE_ADDED_TO_VEHICLE, TYPE_ON_VEHICLE_UP_TO_VISIT and TYPE_SIMULTANEOUSLY_ADDED_AND_REMOVED the configurations UV --> a1 --> r1 --> a2 --> r2, a1 --> r1 --> a2 --> r2 --> A and a1 --> r1 --> AR --> a2 --> r2 are acceptable, whereas the configurations a1 --> a2 --> r1 --> ..., or A --> a1 --> r1 --> ..., or a1 --> r1 --> UV --> ... are not feasible.
It also verifies same-vehicle and temporal type requirements. A node of type T_d with a same-vehicle requirement for type T_r needs to be served by the same vehicle as a node of type T_r. Temporal requirements, on the other hand, can take effect either when the dependent type is being added to the route or when it's removed from it, which is determined by the dependent node's VisitTypePolicy. In the above example:
- If T3 is required on the same vehicle as T1, A, AR or UV must be on the same vehicle as a1.
- If T2 is required when adding T1, a2 must be visited before a1, and if r2 is also visited on the route, it must be after a1, i.e. T2 must be on the vehicle when a1 is visited: ... --> a2 --> ... --> a1 --> ... --> r2 --> ...
- If T3 is required when removing T1, T3 needs to be on the vehicle when r1 is visited: ... --> A --> ... --> r1 --> ... OR ... --> r1 --> ... --> UV --> ...
Public Member Functions | |
TypeRegulationsConstraint (const RoutingModel &model) | |
void | Post () override |
This method is called when the constraint is processed by the solver. More... | |
void | InitialPropagate () override |
This method performs the initial propagation of the constraint. More... | |
std::string | DebugString () const override |
void | PostAndPropagate () |
Calls Post and then Propagate to initialize the constraints. More... | |
virtual void | Accept (ModelVisitor *const visitor) const |
Accepts the given visitor. More... | |
bool | IsCastConstraint () const |
Is the constraint created by a cast from expression to integer variable? More... | |
virtual IntVar * | Var () |
Creates a Boolean variable representing the status of the constraint (false = constraint is violated, true = constraint is satisfied). More... | |
Solver * | solver () const |
void | FreezeQueue () |
This method freezes the propagation queue. More... | |
void | UnfreezeQueue () |
This method unfreezes the propagation queue. More... | |
void | EnqueueDelayedDemon (Demon *const d) |
This method pushes the demon onto the propagation queue. More... | |
void | EnqueueVar (Demon *const d) |
void | ExecuteAll (const SimpleRevFIFO< Demon * > &demons) |
void | EnqueueAll (const SimpleRevFIFO< Demon * > &demons) |
void | set_action_on_fail (Solver::Action a) |
void | reset_action_on_fail () |
This method clears the failure callback. More... | |
void | set_variable_to_clean_on_fail (IntVar *v) |
Shortcut for variable cleaner. More... | |
virtual std::string | name () const |
Object naming. More... | |
void | set_name (const std::string &name) |
bool | HasName () const |
Returns whether the object has been named or not. More... | |
virtual std::string | BaseName () const |
Returns a base name for automatic naming. More... | |
Constructor & Destructor Documentation
◆ TypeRegulationsConstraint()
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explicit |
Member Function Documentation
◆ Accept()
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virtualinherited |
Accepts the given visitor.
Reimplemented in Pack.
◆ BaseName()
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virtualinherited |
Returns a base name for automatic naming.
Reimplemented in BooleanVar.
◆ DebugString()
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overridevirtualinherited |
Reimplemented from PropagationBaseObject.
Reimplemented in Pack, and GlobalVehicleBreaksConstraint.
◆ EnqueueAll()
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inherited |
◆ EnqueueDelayedDemon()
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inlineinherited |
This method pushes the demon onto the propagation queue.
It will be processed directly if the queue is empty. It will be enqueued according to its priority otherwise.
Definition at line 3192 of file constraint_solver.h.
◆ EnqueueVar()
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inlineinherited |
Definition at line 3193 of file constraint_solver.h.
◆ ExecuteAll()
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inherited |
◆ FreezeQueue()
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inlineinherited |
This method freezes the propagation queue.
It is useful when you need to apply multiple modifications at once.
Definition at line 3183 of file constraint_solver.h.
◆ HasName()
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inherited |
Returns whether the object has been named or not.
◆ InitialPropagate()
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overridevirtual |
This method performs the initial propagation of the constraint.
It is called just after the post.
Implements Constraint.
◆ IsCastConstraint()
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inherited |
Is the constraint created by a cast from expression to integer variable?
◆ name()
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virtualinherited |
Object naming.
◆ Post()
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overridevirtual |
This method is called when the constraint is processed by the solver.
Its main usage is to attach demons to variables.
Implements Constraint.
◆ PostAndPropagate()
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inherited |
Calls Post and then Propagate to initialize the constraints.
This is usually done in the root node.
◆ reset_action_on_fail()
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inlineinherited |
This method clears the failure callback.
Definition at line 3206 of file constraint_solver.h.
◆ set_action_on_fail()
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inlineinherited |
Definition at line 3200 of file constraint_solver.h.
◆ set_name()
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inherited |
◆ set_variable_to_clean_on_fail()
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inlineinherited |
Shortcut for variable cleaner.
Definition at line 3209 of file constraint_solver.h.
◆ solver()
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inlineinherited |
Definition at line 3179 of file constraint_solver.h.
◆ UnfreezeQueue()
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inlineinherited |
This method unfreezes the propagation queue.
All modifications that happened when the queue was frozen will be processed.
Definition at line 3187 of file constraint_solver.h.
◆ Var()
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virtualinherited |
Creates a Boolean variable representing the status of the constraint (false = constraint is violated, true = constraint is satisfied).
It returns nullptr if the constraint does not support this API.
The documentation for this class was generated from the following file: