Queue for all spikes arriving into a neuron. More...

#include <slice_ring_buffer.h>

Classes
struct	SpikeInfo
	Information about spike. More...

Public Member Functions
	SliceRingBuffer ()

void	add_spike (const delay rel_delivery, const long_t stamp, const double ps_offset, const double weight)
	Add spike to queue. More...

void	add_refractory (const long_t stamp, const double_t ps_offset)
	Add refractory event to queue. More...

void	prepare_delivery ()
	Prepare for spike delivery in current slice by sorting. More...

void	discard_events ()
	Discard all events in current slice. More...

bool	get_next_spike (const long_t req_stamp, double_t &ps_offset, double_t &weight, bool &end_of_refract)
	Return next spike. More...

void	clear ()
	Clear buffer. More...

void	resize ()
	Resize the buffer according to min_delay and max_delay. More...

Private Attributes
std::vector< std::vector < SpikeInfo > >	queue_
	entire queue, one slot per min_delay block within max_delay More...

std::vector< SpikeInfo > *	deliver_
	slot to deliver from More...

SpikeInfo	refract_
	pseudo-event for return from refractoriness More...

Detailed Description

Queue for all spikes arriving into a neuron.

Spikes are stored unsorted on arrival, but are sorted when prepare_delivery() is called. They can then be retrieved one by one in correct temporal order. Coinciding spikes are combined into one, see get_next_spike().

Data is organized as follows:

The time of the next return from refractoriness is stored in a separate variable and checked explicitly; otherwise, we'd have to re-sort data during updating.
We have a pseudo-ring of Nbuff=ceil((min_del+max_del)/min_del) elements. Each element is a vector storing incoming spikes that are due during a given time slice.

Note

The following assumptions underlie the handling of pseudo-events for return from refractoriness:

There is at most one such event per time step (value of time stamp).

Constructor & Destructor Documentation

nest::SliceRingBuffer::SliceRingBuffer ( )

Member Function Documentation

void nest::SliceRingBuffer::add_refractory	(	const long_t	stamp,
		const double_t	ps_offset
	)

inline

Add refractory event to queue.

The refractory event is actually stored as a pseudo-event.

Parameters

stamp	Delivery time
ps_offset	Precise timing offset of spike time

References assert(), nest::names::max, nest::SliceRingBuffer::SpikeInfo::ps_offset_, refract_, and nest::SliceRingBuffer::SpikeInfo::stamp_.

Referenced by nest::iaf_psc_delta_canon::update().

void nest::SliceRingBuffer::add_spike	(	const delay	rel_delivery,
		const long_t	stamp,
		const double	ps_offset,
		const double	weight
	)

inline

Add spike to queue.

Parameters

rel_delivery	relative delivery time
stamp	Delivery time
ps_offset	Precise timing offset of spike time
weight	Weight of spike.

References assert(), nest::Scheduler::get_slice_modulo(), and queue_.

Referenced by nest::parrot_neuron_ps::handle(), and nest::iaf_psc_delta_canon::handle().

void nest::SliceRingBuffer::clear ( )

Clear buffer.

References nest::names::clear.

Referenced by nest::parrot_neuron_ps::init_buffers_().

void nest::SliceRingBuffer::discard_events ( )

Discard all events in current slice.

References nest::Scheduler::get_slice_modulo().

bool nest::SliceRingBuffer::get_next_spike	(	const long_t	req_stamp,
		double_t &	ps_offset,
		double_t &	weight,
		bool &	end_of_refract
	)

inline

Return next spike.

Parameters

req_stamp	Request spike with this stamp. Queue should never contain spikes with smaller stamps. Spikes with larger stamps are left in queue.
ps_offset	PS-sense offset of spike time
weight	Spike weight
end_of_refract	True if spike is pseudo-spike marking end of refractory period

Returns: true if spike available, false otherwise

Note: If return from refractoriness coincides with a spike, return from refractoriness is returned. If several spikes coincide, the sum of their weights is returned a single spike.

References assert(), deliver_, nest::names::max, nest::SliceRingBuffer::SpikeInfo::ps_offset_, refract_, and nest::SliceRingBuffer::SpikeInfo::stamp_.

Referenced by nest::parrot_neuron_ps::update(), and nest::iaf_psc_delta_canon::update().

void nest::SliceRingBuffer::prepare_delivery ( )

Prepare for spike delivery in current slice by sorting.

References nest::Scheduler::get_slice_modulo().

Referenced by nest::parrot_neuron_ps::update(), and nest::iaf_psc_delta_canon::update().

void nest::SliceRingBuffer::resize ( )

Resize the buffer according to min_delay and max_delay.

References nest::names::clear, nest::Scheduler::get_max_delay(), and nest::Scheduler::get_min_delay().

Referenced by nest::parrot_neuron_ps::init_buffers_().