Base class implementing archiving for node models supporting e-prop plasticity. More...

#include <eprop_archiving_node.h>

Inheritance diagram for nest::EpropArchivingNode< HistEntryT >:

Collaboration diagram for nest::EpropArchivingNode< HistEntryT >:

Public Member Functions
	EpropArchivingNode ()
	Constructs a new EpropArchivingNode object.

	EpropArchivingNode (const EpropArchivingNode &n)
	Constructs a new EpropArchivingNode object by copying another EpropArchivingNode object.

void	register_eprop_connection () override
	Registers an eprop connection.

void	initialize_update_history () override
	Initializes the update history.

void	write_update_to_history (const long t_previous_update, const long t_current_update, const bool is_flush_event, const bool previous_was_flush_event) override
	Registers the current update in the update history and deregisters the previous update.

void	require_eprop_history_entry (const typename std::vector< HistEntryT >::iterator eprop_hist_it, const long time_step) const
	Requires that an e-prop history iterator points to the expected time step.

std::vector< HistEntryEpropUpdate >::iterator	get_update_history (const long time_step)
	Retrieves the update history entry for a specific time step.

std::vector< HistEntryT >::iterator	get_eprop_history (const long time_step)
	Retrieves the eprop history entry for a specified time step.

void	erase_used_eprop_history () override
	Erases the used eprop history for `bsshslm_2020` models.

void	erase_used_eprop_history (const long t_spike, const long t_spike_previous) override
	Erases the used eprop history.

double	get_eprop_history_duration () const
	Retrieves eprop history size.

long	get_eprop_isi_trace_cutoff () const
	Retrieves the eprop ISI trace cutoff.

Public Member Functions inherited from nest::Node
	Node ()

	Node (Node const &)

virtual	~Node ()

virtual Node *	clone () const
	This function creates a new object by calling the derived class' copy constructor and returning its pointer.

virtual bool	has_proxies () const
	Returns true if the node has proxies on remote threads.

virtual bool	supports_urbanczik_archiving () const
	Returns true if the node supports the Urbanczik-Senn plasticity rule.

virtual bool	local_receiver () const
	Returns true if the node only receives events from nodes/devices on the same thread.

virtual bool	one_node_per_process () const
	Returns true if the node exists only once per process, but does not have proxies on remote threads.

virtual bool	is_off_grid () const
	Returns true if the node sends/receives off-grid events.

virtual bool	is_proxy () const
	Returns true if the node is a proxy node.

std::string	get_name () const
	Return class name.

virtual std::string	get_element_type () const
	Return the element type of the node.

size_t	get_node_id () const
	Return global Network ID.

int	get_model_id () const
	Return model ID of the node.

bool	is_frozen () const
	Returns true if node is frozen, i.e., shall not be updated.

bool	node_uses_wfr () const
	Returns true if the node uses the waveform relaxation method.

void	set_node_uses_wfr (const bool)
	Sets node_uses_wfr_ member variable (to be able to set it to "true" for any class derived from Node)

void	init ()
	Initialize node prior to first simulation after node has been created.

virtual void	pre_run_hook ()=0
	Re-calculate dependent parameters of the node.

virtual void	calibrate_time (const TimeConverter &)
	Re-calculate time-based properties of the node.

virtual void	post_run_cleanup ()
	Cleanup node after Run.

virtual void	finalize ()
	Finalize node.

virtual void	update (Time const &, const long, const long)=0
	Advance the state of the node in time through the given interval.

virtual bool	wfr_update (Time const &, const long, const long)
	Advance the state of the node in time through the given interval (see Node::update() for more details).

virtual void	set_status (const Dictionary &)=0
	Change properties of the node according to the entries in the dictionary.

virtual void	get_status (Dictionary &) const =0
	Export properties of the node by setting entries in the status dictionary.

virtual size_t	send_test_event (Node &receiving_node, size_t receptor_type, synindex syn_id, bool dummy_target)
	Send an event to the receiving_node passed as an argument.

virtual size_t	handles_test_event (SpikeEvent &, size_t receptor_type)
	Check if the node can handle a particular event and receptor type.

virtual size_t	handles_test_event (WeightRecorderEvent &, size_t receptor_type)

virtual size_t	handles_test_event (RateEvent &, size_t receptor_type)

virtual size_t	handles_test_event (DataLoggingRequest &, size_t receptor_type)

virtual size_t	handles_test_event (CurrentEvent &, size_t receptor_type)

virtual size_t	handles_test_event (ConductanceEvent &, size_t receptor_type)

virtual size_t	handles_test_event (DoubleDataEvent &, size_t receptor_type)

virtual size_t	handles_test_event (DSSpikeEvent &, size_t receptor_type)

virtual size_t	handles_test_event (DSCurrentEvent &, size_t receptor_type)

virtual size_t	handles_test_event (GapJunctionEvent &, size_t receptor_type)

virtual size_t	handles_test_event (InstantaneousRateConnectionEvent &, size_t receptor_type)

virtual size_t	handles_test_event (DiffusionConnectionEvent &, size_t receptor_type)

virtual size_t	handles_test_event (DelayedRateConnectionEvent &, size_t receptor_type)

virtual size_t	handles_test_event (LearningSignalConnectionEvent &, size_t receptor_type)

virtual size_t	handles_test_event (SICEvent &, size_t receptor_type)

virtual void	sends_secondary_event (GapJunctionEvent &ge)
	Required to check, if source neuron may send a SecondaryEvent.

virtual void	sends_secondary_event (InstantaneousRateConnectionEvent &re)
	Required to check, if source neuron may send a SecondaryEvent.

virtual void	sends_secondary_event (DiffusionConnectionEvent &de)
	Required to check, if source neuron may send a SecondaryEvent.

virtual void	sends_secondary_event (DelayedRateConnectionEvent &re)
	Required to check, if source neuron may send a SecondaryEvent.

virtual void	sends_secondary_event (LearningSignalConnectionEvent &re)
	Required to check if source node may send a LearningSignalConnectionEvent.

virtual void	sends_secondary_event (SICEvent &sic)
	Required to check if source node may send a SICEvent.

virtual void	register_stdp_connection (double, double)
	Register a STDP connection.

virtual long	get_shift () const
	Retrieves the temporal shift of the signal.

virtual bool	is_eprop_recurrent_node () const
	Checks if the node is part of the recurrent network and thus not a readout neuron.

virtual void	handle (SpikeEvent &e)
	Handle incoming spike events.

virtual void	handle (WeightRecorderEvent &e)
	Handle incoming weight recording events.

virtual void	handle (RateEvent &e)
	Handler for rate events.

virtual void	handle (DataLoggingRequest &e)
	Handler for universal data logging request.

virtual void	handle (DataLoggingReply &e)
	Handler for universal data logging request.

virtual void	handle (CurrentEvent &e)
	Handler for current events.

virtual void	handle (ConductanceEvent &e)
	Handler for conductance events.

virtual void	handle (DoubleDataEvent &e)
	Handler for DoubleData events.

virtual void	handle (GapJunctionEvent &e)
	Handler for gap junction events.

virtual void	handle (InstantaneousRateConnectionEvent &e)
	Handler for rate neuron events.

virtual void	handle (DiffusionConnectionEvent &e)
	Handler for rate neuron events.

virtual void	handle (DelayedRateConnectionEvent &e)
	Handler for delay rate neuron events.

virtual void	handle (LearningSignalConnectionEvent &e)
	Handler for learning signal connection events.

virtual void	handle (SICEvent &e)
	Handler for slow inward current events (SICEvents).

virtual double	get_Ca_minus () const
	Return the Ca_minus value at time Ca_t which corresponds to the time of the last update in Calcium concentration which is performed each time a Node spikes.

virtual double	get_synaptic_elements (std::string) const
	Get the number of synaptic element for the current Node at Ca_t which corresponds to the time of the last spike.

virtual int	get_synaptic_elements_vacant (std::string) const
	Get the number of vacant synaptic element for the current Node Return 0 if not overridden.

virtual int	get_synaptic_elements_connected (std::string) const
	Get the number of connected synaptic element for the current Node.

virtual std::map< std::string, double >	get_synaptic_elements () const
	Get the number of all synaptic elements for the current Node at time t.

virtual void	update_synaptic_elements (double)
	Triggers the update of all SynapticElements stored in the synaptic_element_map_.

virtual void	decay_synaptic_elements_vacant ()
	Is used to reduce the number of synaptic elements in the node through time.

virtual void	connect_synaptic_element (std::string, int)
	Is used to update the number of connected synaptic elements (SynapticElement::z_connected_) when a synapse is formed or deleted.

virtual double	get_K_value (double t)
	return the Kminus value at t (in ms).

virtual double	get_LTD_value (double t)

virtual void	get_K_values (double t, double &Kminus, double &nearest_neighbor_Kminus, double &Kminus_triplet)
	write the Kminus, nearest_neighbor_Kminus, and Kminus_triplet values at t (in ms) to the provided locations.

virtual void	get_history (double t1, double t2, std::deque< histentry >::iterator start, std::deque< histentry >::iterator finish)
	return the spike history for (t1,t2].

virtual void	get_LTP_history (double t1, double t2, std::deque< histentry_extended >::iterator start, std::deque< histentry_extended >::iterator finish)

virtual void	get_urbanczik_history (double t1, double t2, std::deque< histentry_extended >::iterator start, std::deque< histentry_extended >::iterator finish, int)

virtual double	get_C_m (int comp)

virtual double	get_g_L (int comp)

virtual double	get_tau_L (int comp)

virtual double	get_tau_s (int comp)

virtual double	get_tau_syn_ex (int comp)

virtual double	get_tau_syn_in (int comp)

virtual void	compute_gradient (const long t_spike, const long t_spike_previous, double &z_previous_buffer, double &z_bar, double &e_bar, double &e_bar_reg, double &epsilon, double &weight, const CommonSynapseProperties &cp, WeightOptimizer *optimizer, bool is_flush_event, bool previous_was_flush_event, double &sum_grad, long &remaining_steps_until_cutoff, long &decay_steps)
	Compute gradient change for eprop synapses.

virtual double	compute_gradient (std::vector< long > &presyn_isis, const long t_previous_update, const long t_previous_trigger_spike, const double kappa, const bool average_gradient)
	Compute gradient change for eprop synapses.

virtual void	event_hook (DSSpikeEvent &)
	Modify Event object parameters during event delivery.

virtual void	event_hook (DSCurrentEvent &)

void	set_thread (size_t)
	Store the number of the thread to which the node is assigned.

size_t	get_thread () const
	Retrieve the number of the thread to which the node is assigned.

void	set_vp (size_t)
	Store the number of the virtual process to which the node is assigned.

size_t	get_vp () const
	Retrieve the number of the virtual process to which the node is assigned.

void	set_model_id (int)
	Set the model id.

void	set_initialized ()
	Execute post-initialization actions in node models.

virtual SignalType	sends_signal () const

virtual SignalType	receives_signal () const

Dictionary	get_status_base ()
	Return a dictionary with the node's properties.

void	set_status_base (const Dictionary &)
	Set status dictionary of a node.

bool	is_model_prototype () const
	Returns true if node is model prototype.

void	set_thread_lid (const size_t)
	set thread local index

size_t	get_thread_lid () const
	get thread local index

virtual void	set_local_device_id (const size_t lsdid)
	Sets the local device id.

virtual size_t	get_local_device_id () const
	Gets the local device id.

void	set_tmp_nc_index (size_t index)
	Set index in node collection; required by ThirdOutBuilder.

size_t	get_tmp_nc_index ()
	Return and invalidate index in node collection; required by ThirdOutBuilder.

Public Member Functions inherited from nest::FlushEventMechanism
	FlushEventMechanism ()
	Default constructor.

	FlushEventMechanism (const FlushEventMechanism &n)
	Copy constructor.

virtual	~FlushEventMechanism ()=default
	Destructor.

void	set_last_event_time (const long last_event_time)
	Sets the time the neuron last sent an event (spike or flush event).

long	get_last_event_time () const
	Gets the last time the neuron sent an event (spike or flush event).

void	pre_run_hook ()
	Re-calculates dependent parameters.

bool	flush_event_is_due (const long current_time) const
	Checks if a flush event is due at the current time.

void	get_status (Dictionary &d) const
	Retrieves parameters and adds them to the status dictionary.

void	set_status (const Dictionary &d, Node *node, const bool check_eprop_constraint=false)
	Sets and validates parameters from the status dictionary.

Public Member Functions inherited from nest::IgnoreAndSpikeMechanism
	IgnoreAndSpikeMechanism ()
	Default constructor.

	IgnoreAndSpikeMechanism (const IgnoreAndSpikeMechanism &n)
	Copy constructor.

virtual	~IgnoreAndSpikeMechanism ()=default
	Virtual destructor.

bool	spike_event_is_due (bool emit_dynamic_spike)
	Updates spike schedule and returns whether a spike should be emitted.

void	get_status (Dictionary &d) const
	Retrieves parameters and adds them to the status dictionary.

void	set_status (const Dictionary &d, Node *node)
	Sets and validates parameters from the status dictionary.

Protected Member Functions
virtual long	model_dependent_history_shift_ () const =0
	Returns the correct shift for history depending on whether it is a normal or a bsshslm_2020 model.

Protected Member Functions inherited from nest::Node
virtual void	init_state_ ()
	Configure state variables depending on runtime information.

virtual void	init_buffers_ ()
	Configure persistent internal data structures.

virtual void	set_initialized_ ()

Model &	get_model_ () const

void	set_frozen_ (bool frozen)
	Mark node as frozen.

template<typename ConcreteNode >
const ConcreteNode &	downcast (const Node &)
	Auxiliary function to downcast a Node to a concrete class derived from Node.

Protected Attributes
size_t	eprop_indegree_
	Number of incoming eprop synapses.

double	eprop_isi_trace_cutoff_
	Time interval from the previous spike until the cutoff of e-prop update computation between two spikes (ms).

std::vector< HistEntryEpropUpdate >	update_history_
	History of updates still needed by at least one synapse.

std::vector< HistEntryT >	eprop_history_
	History of dynamic variables needed for e-prop plasticity.

const long	offset_gen_ = 1
	Offset since generator signals start from time step 1.

const long	delay_in_rec_ = 1
	Transmission delay from input to recurrent neurons.

const long	delay_rec_out_ = 1
	Transmission delay from recurrent to output neurons.

const long	delay_out_norm_ = 1
	Transmission delay between output neurons for normalization.

const long	delay_out_rec_ = 1
	Transmission delay from output neurons to recurrent neurons.

Protected Attributes inherited from nest::FlushEventMechanism
double	flush_event_send_interval_
	Interval since previous event after which a flush event is sent (ms).

long	flush_event_send_interval_steps_
	Interval since previous event after which a flush event is sent (steps).

long	last_event_time_
	Time of last spike or flush event (steps).

Additional Inherited Members
Public Attributes inherited from nest::Node
DeprecationWarning	deprecation_warning
	Member of DeprecationWarning class to be used by models if parameters are deprecated.

Detailed Description

template<typename HistEntryT>
class nest::EpropArchivingNode< HistEntryT >

Base class implementing archiving for node models supporting e-prop plasticity.

Base class implementing an intermediate archiving node model for node models supporting e-prop plasticity according to Bellec et al. (2020) and supporting additional biological features described in Korcsak-Gorzo et al. (2025).

A node which archives the history of dynamic variables, the firing rate regularization, and update times needed to calculate the weight updates for e-prop plasticity. It further provides a set of get, write, and set functions for these histories and the hardcoded shifts to synchronize the factors of the plasticity rule.

Template Parameters

HistEntryT The type of history entry.

Constructor & Destructor Documentation

◆ EpropArchivingNode() [1/2]

template<typename HistEntryT >

nest::EpropArchivingNode< HistEntryT >::EpropArchivingNode ( )

Constructs a new EpropArchivingNode object.

◆ EpropArchivingNode() [2/2]

template<typename HistEntryT >

nest::EpropArchivingNode< HistEntryT >::EpropArchivingNode ( const EpropArchivingNode< HistEntryT > & n )

Constructs a new EpropArchivingNode object by copying another EpropArchivingNode object.

Parameters

n	The other object to copy.

Member Function Documentation

◆ erase_used_eprop_history() [1/2]

template<typename HistEntryT >

void nest::EpropArchivingNode< HistEntryT >::erase_used_eprop_history ( )

overridevirtual

Erases the used eprop history for bsshslm_2020 models.

Erases e-prop history entries for update intervals during which no spikes were sent to the target neuron, and any entries older than the earliest time stamp required by the first update in the history.

Reimplemented from nest::Node.

References nest::SimulationManager::get_eprop_update_interval(), nest::Time::get_steps(), nest::kernel(), and nest::KernelManager::simulation_manager.

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◆ erase_used_eprop_history() [2/2]

template<typename HistEntryT >

void nest::EpropArchivingNode< HistEntryT >::erase_used_eprop_history	(	const long	t_spike,
		const long	t_spike_previous
	)

overridevirtual

Erases the used eprop history.

Erases e-prop history entries between the last and penultimate updates if they exceed the inter-spike interval trace cutoff and any entries older than the earliest time stamp required by the first update.

Parameters

t_spike	The time step of the current spike.
t_spike_previous	The time step of the previous spike.

Reimplemented from nest::Node.

◆ get_eprop_history()

template<typename HistEntryT >

std::vector< HistEntryT >::iterator nest::EpropArchivingNode< HistEntryT >::get_eprop_history ( const long time_step )

Retrieves the eprop history entry for a specified time step.

Parameters

time_step The time step.

Returns: An iterator pointing to the eprop history entry for the specified time step.

◆ get_eprop_history_duration()

template<typename HistEntryT >

double nest::EpropArchivingNode< HistEntryT >::get_eprop_history_duration ( ) const

inline

Retrieves eprop history size.

Retrieves the size of the eprop history buffer.

Returns: The duration of the eprop history buffer (ms).

References nest::Time::get_ms(), and nest::Time::get_resolution().

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◆ get_eprop_isi_trace_cutoff()

template<typename HistEntryT >

long nest::EpropArchivingNode< HistEntryT >::get_eprop_isi_trace_cutoff ( ) const

inline

Retrieves the eprop ISI trace cutoff.

Retrieves the time interval from the previous spike until the cutoff of e-prop update computation between two spikes (ms).

Returns: The eprop ISI trace cutoff (steps).

References nest::EpropArchivingNode< HistEntryT >::eprop_isi_trace_cutoff_, and nest::Time::get_steps().

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◆ get_update_history()

template<typename HistEntryT >

std::vector< HistEntryEpropUpdate >::iterator nest::EpropArchivingNode< HistEntryT >::get_update_history ( const long time_step )

Retrieves the update history entry for a specific time step.

Parameters

time_step The time step.

Returns: An iterator pointing to the update history for the specified time step.

◆ initialize_update_history()

template<typename HistEntryT >

void nest::EpropArchivingNode< HistEntryT >::initialize_update_history ( )

overridevirtual

Initializes the update history.

The time for the first entry of the update history is set to the neuron specific shift for bsshslm_2020 models and to the negative transmission delay from the recurrent to the output layer otherwise.

Exceptions

IllegalConnection

Reimplemented from nest::Node.

◆ model_dependent_history_shift_()

template<typename HistEntryT >

virtual long nest::EpropArchivingNode< HistEntryT >::model_dependent_history_shift_ ( ) const

protectedpure virtual

Returns the correct shift for history depending on whether it is a normal or a bsshslm_2020 model.

Returns: The history shift (steps).

Implemented in nest::EpropArchivingNodeReadout< hist_shift_required >, nest::EpropArchivingNodeReadout< false >, nest::EpropArchivingNodeReadout< true >, nest::EpropArchivingNodeRecurrent< hist_shift_required >, nest::EpropArchivingNodeRecurrent< false >, and nest::EpropArchivingNodeRecurrent< true >.

◆ register_eprop_connection()

template<typename HistEntryT >

void nest::EpropArchivingNode< HistEntryT >::register_eprop_connection ( )

overridevirtual

Registers an eprop connection.

Exceptions

IllegalConnection

Reimplemented from nest::Node.

◆ require_eprop_history_entry()

template<typename HistEntryT >

void nest::EpropArchivingNode< HistEntryT >::require_eprop_history_entry	(	const typename std::vector< HistEntryT >::iterator	eprop_hist_it,
		const long	time_step
	)		const

Requires that an e-prop history iterator points to the expected time step.

Parameters

eprop_hist_it	Iterator into the e-prop history.
time_step	The expected time step.

Exceptions

KernelException if the iterator is at the end or points to a different time step.

◆ write_update_to_history()

template<typename HistEntryT >

void nest::EpropArchivingNode< HistEntryT >::write_update_to_history	(	const long	t_previous_update,
		const long	t_current_update,
		const bool	is_flush_event,
		const bool	previous_was_flush_event
	)

overridevirtual

Registers the current update in the update history and deregisters the previous update.

Parameters

t_previous_update	The time step of the previous update.
t_current_update	The time step of the current update.
eprop_isi_trace_cutoff	The cutoff value for the eprop inter-spike interval trace (optional, default: 0).

template<typename HistEntryT >

double nest::EpropArchivingNode< HistEntryT >::eprop_isi_trace_cutoff_

protected

Time interval from the previous spike until the cutoff of e-prop update computation between two spikes (ms).

Referenced by nest::EpropArchivingNode< HistEntryT >::get_eprop_isi_trace_cutoff().

◆ offset_gen_

template<typename HistEntryT >

const long nest::EpropArchivingNode< HistEntryT >::offset_gen_ = 1

protected

Offset since generator signals start from time step 1.

◆ update_history_

template<typename HistEntryT >

std::vector< HistEntryEpropUpdate > nest::EpropArchivingNode< HistEntryT >::update_history_

protected

History of updates still needed by at least one synapse.

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

	NEST main@caf0ae8

Public Member Functions

Protected Member Functions

Protected Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ EpropArchivingNode() [1/2]

◆ EpropArchivingNode() [2/2]

Member Function Documentation

◆ erase_used_eprop_history() [1/2]

◆ erase_used_eprop_history() [2/2]

◆ get_eprop_history()

◆ get_eprop_history_duration()

◆ get_eprop_isi_trace_cutoff()

◆ get_update_history()

◆ initialize_update_history()

◆ model_dependent_history_shift_()

◆ register_eprop_connection()

◆ require_eprop_history_entry()

◆ write_update_to_history()

Member Data Documentation

◆ delay_in_rec_

◆ delay_out_norm_

◆ delay_out_rec_

◆ delay_rec_out_

◆ eprop_history_

◆ eprop_indegree_

◆ eprop_isi_trace_cutoff_

◆ offset_gen_

◆ update_history_