gap_junction.h

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/*
 *  gap_junction.h
 *
 *  This file is part of NEST.
 *
 *  Copyright (C) 2004 The NEST Initiative
 *
 *  NEST is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  NEST is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with NEST.  If not, see <http://www.gnu.org/licenses/>.
 *
 */
 
#ifndef GAP_JUNCTION_H
#define GAP_JUNCTION_H
 
#include "connection.h"
 
namespace nest
{
 
/* BeginUserDocs: synapse, electrical
 
Short description
+++++++++++++++++
 
Synapse type for gap-junction connections
 
Description
+++++++++++
 
``gap_junction`` is a connector to create gap junctions between pairs of
neurons. Gap junctions are bidirectional connections.  In order to
create one accurate gap-junction connection between neurons i and j
two NEST connections are required: For each created connection a
second connection with the exact same parameters in the opposite
direction is required. NEST provides the possibility to create both
connections with a single call to Connect via the make_symmetric flag.
 
The value of the parameter ``delay`` is ignored for connections of
type ``gap_junction``.
 
See also :footcite:p:`Hahne2015`, :footcite:p:`Mancilla2007`.
 
Sends
+++++
 
GapJunctionEvent
 
References
++++++++++
 
.. footbibliography::
 
See also
++++++++
 
hh_psc_alpha_gap
 
Examples using this model
+++++++++++++++++++++++++
 
.. listexamples:: gap_junction
 
EndUserDocs */
 
void register_gap_junction( const std::string& name );
 
template < typename targetidentifierT >
class gap_junction : public Connection< targetidentifierT >
{
 
public:
  // this line determines which common properties to use
  typedef CommonSynapseProperties CommonPropertiesType;
  typedef Connection< targetidentifierT > ConnectionBase;
 
  static constexpr ConnectionModelProperties properties =
    ConnectionModelProperties::REQUIRES_SYMMETRIC | ConnectionModelProperties::SUPPORTS_WFR;
 
  gap_junction()
    : ConnectionBase()
    , weight_( 1.0 )
  {
  }
 
  std::unique_ptr< SecondaryEvent > get_secondary_event();
 
  // Explicitly declare all methods inherited from the dependent base
  // ConnectionBase. This avoids explicit name prefixes in all places these
  // functions are used. Since ConnectionBase depends on the template parameter,
  // they are not automatically found in the base class.
  using ConnectionBase::get_delay_steps;
  using ConnectionBase::get_rport;
  using ConnectionBase::get_target;
 
  void
  check_connection( Node& s, Node& t, size_t receptor_type, const CommonPropertiesType& )
  {
    GapJunctionEvent ge;
 
    s.sends_secondary_event( ge );
    ge.set_sender( s );
    Connection< targetidentifierT >::target_.set_rport( t.handles_test_event( ge, receptor_type ) );
    Connection< targetidentifierT >::target_.set_target( &t );
  }
 
  bool
  send( Event& e, size_t t, const CommonSynapseProperties& )
  {
    e.set_weight( weight_ );
    e.set_receiver( *get_target( t ) );
    e.set_rport( get_rport() );
    e();
    return true;
  }
 
  void get_status( Dictionary& d ) const;
 
  void set_status( const Dictionary& d, ConnectorModel& cm );
 
  void
  set_weight( double w )
  {
    weight_ = w;
  }
 
  void
  set_delay( double )
  {
    throw BadProperty( "gap_junction connection has no delay" );
  }
 
private:
  double weight_;  
};
 
template < typename targetidentifierT >
constexpr ConnectionModelProperties gap_junction< targetidentifierT >::properties;
 
template < typename targetidentifierT >
void
gap_junction< targetidentifierT >::get_status( Dictionary& d ) const
{
  // We have to include the delay here to prevent
  // errors due to internal calls of
  // this function in SLI/pyNEST
  ConnectionBase::get_status( d );
  d[ names::weight ] = weight_;
  d[ names::size_of ] = static_cast< long >( sizeof( *this ) );
}
 
template < typename targetidentifierT >
std::unique_ptr< SecondaryEvent >
gap_junction< targetidentifierT >::get_secondary_event()
{
  return std::make_unique< GapJunctionEvent >();
}
 
template < typename targetidentifierT >
void
gap_junction< targetidentifierT >::set_status( const Dictionary& d, ConnectorModel& cm )
{
  // If the delay is set, we throw a BadProperty
  if ( d.known( names::delay ) )
  {
    throw BadProperty( "gap_junction connection has no delay" );
  }
 
  ConnectionBase::set_status( d, cm );
  d.update_value( names::weight, weight_ );
}
 
}  // namespace
 
#endif /* #ifndef GAP_JUNCTION_H */