Entity

An instance of this is a runnable entity. Input ports correspond to input receptors, Output ports correspond to spike generators, voltage probes etc. Many connections can be made to/from any port. Input ConnectionIDs are unique for an entity, so can be used to look up extra connection information stored inside the entity.

• Entity( Population p, EntityClass e )
  void         init(Population p, int index) 
  Time         handleEvents(EventList el, Time t) 
  void         reset() 
  void         destroy() 
   
  void         sendEvent( PortID c, Event e )  
  void         sendEvent( EntityID deste, PortID destp, Event e )
  void         defaultEventHandler( Event e ) 
  Population   getPopulation() 
  EntityClass  getClass()     
  EntityID     getID()
  
  PopulationTree getPopulationTree(Time t)  
  EntityClasses  getEntityClasses()  
  EventClasses   getEventClasses()  
  EntityClass    lookupEntityClass( String name );
  EntityID       lookupEntity( Time t, String name );
  Population     lookupPopulation( Time t, String name );
   
  void         construct ( Time t, PopulationBuilder p, Callback c)
  void         destroy ( Time t, Population p, Callback c )
  void         connect ( Time t, Projection p, Callback c )
  void         disconnect ( Time t, Projection p, Callback c )
  void         updateEntity( Time t, EntityID e, EntityUpdate eu, Callback c )
  void         queryEntity( Time t, EntityID e, EntityQuery eq, Callback c )
  void         updatePopulation( Time t, Population p, EntityUpdate eu, Callback c )
  void         queryPopulation( Time t, Population p, EntityQuery eq, Callback c )
  void         queryOutputConnections( Time t, PortID p, ConnectionQuery cq, Callback cb );
  
  Vector       getInPortIDs()  
  Vector       getOutPortIDs()  
  PortID       addOutPort(EventClass ec) 
  PortID       addInPort (EventClass ec)  
  Vector       getClassesOfInPort(PortID pid)  
  Vector       getClassesOfOutPort(PortID pid) 
  int          getNumInConnections(PortID inport) 
  int          getNumOutConnections(PortID outport)  
  Vector       getInConnections(PortID inport)  
  void         addOutConnection(PortID outport, Time delay, 
                 EntityID dest, PortID destinport, ConnectionID destconn)
  void         deleteOutConnection(PortID outport, EntityID dest, 
                 PortID destinport, ConnectionID destconn)
  ConnectionID addInConnection(Connection c)
  void         deleteInConnection(ConnectionID cid)
  void         deleteInPort(PortID)
  void         deleteOutPort(PortID)
  
  void         zeroOutputDelay()
  void         resetOutputDelay()
  Time         getMinOutputDelay()  
  Time         getLocalTime()
  

• The crucial method for an entity to implement is handleEvents() which should advance the entity's time to at least t and return the time actually advanced to (which may be later than t, as long as the state can be rewound back to t and no new events are generated after t). reset() and destroy inform an entity that it should reset its simulation time, or remove any allocated storage.

  The entity's minimum output delay is available using getMinOutputDelay(); this will be the minimum delay on any of its output ports, or if there are no output connections, a positive value determined by the kernel. This output delay is imposed on every kernel request the entity makes (i.e. responses to queries, requests to construct and link other entities). If this is not acceptable to the model, the output delay can be zeroed using zeroOutputDelay(), and then unzeroed using resetOutputDelay(). For example, to perform a sequence of queries/responses/new queries at a specific instant of time while a simulation is running, zero the output delay of the population concerned, perform the updates/queries, then reset the output delay.