# Command: cont_delay_synapse

NEST HelpDesk | Command Index | NEST Quick Reference

Name:

    cont_delay_synapse - Synapse type for continuous delays

Description:

      cont_delay_synapse relaxes the condition that NEST only implements delays
      which are an integer multiple of the time step h. A continuous delay is
      decomposed into an integer part (delay_) and a double (delay_offset_) so
      that the actual delay is given by  delay_*h	- delay_offset_. This can be
      combined with off-grid spike times.

      Example:
      0 << /resolution 1.0 >> SetStatus

      /sg /spike_generator << /precise_times true /spike_times [ 2.0 5.5 ] >> Create
      def
      /n  /iaf_psc_delta_canon Create def
      /sd /spike_detector << /precise_times true /record_to [ /memory ] >> Create
      def

      /cont_delay_synapse << /weight 100. /delay 1.7 >> SetDefaults
      sg n /cont_delay_synapse Connect
      n sd Connect

      10 Simulate

      sd GetStatus /events/times :: ==   %  --> <. 3.7 7.2 .>

Transmits:

    SpikeEvent, RateEvent, CurrentEvent, ConductanceEvent,
      DoubleDataEvent

Remarks:

      All delays set by the normal NEST Connect function will be rounded, even when
      using cont_delay_connection. To set non-grid delays, you must either

      1) set the delay as synapse default, as in the example above
      2) set the delay for each synapse after the connections have been created,
      e.g.,

      sg n 100. 1.0 /cont_delay_synapse Connect
      << /source [ sg ] /synapse_model /cont_delay_synapse >> GetConnections
      { << /delay 1.7 >> SetStatus }
      forall

      Alternative 1) is much more efficient, but all synapses then will have the
      same delay.
      Alternative 2) is slower, but allows individual delay values.

      Continuous delays cannot be shorter than the simulation resolution.

References:

    none

Author:

    Abigail Morrison

FirstVersion:

    June 2007

SeeAlso:

- synapsedict
- static_synapse
- iaf_psc_alpha_canon

Source:

    /opt/conda/conda-bld/nest_1531570948828/work/models/cont_delay_connection.h

NEST HelpDesk | Command Index | NEST Quick Reference

© 2004 The NEST Initiative