# Command: testsuite::test_iaf_dc_aligned_automatic

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Name:

    testsuite::test_iaf_dc_aligned_automatic - sli script for test of iaf_neuron resolution independence

Synopsis:

    (test_iaf_dc_aligned_automatic) run -> compare response with reference data

Description:

      test_iaf_dc_aligned_automatic.sli is a modified version of
      test_iaf_dc_aligned_delay.sli .

      The code of this program is now identical to
      test_iaf_dc_aligned_delay.sli. Previous versions used a different
      definition of start which was not independent of the resolution.
      Therefore, an additional device property /on was required.  See
      test_iaf_dc_aligned_automatic.sli for details.

      The documentation below refers to the old definition of start

      The output generated is exactly identical to the output of the
      previous file. The dependence  of the simulation script on the
      computation step size is completely removed by using the capability
      of the DC generator to adjust the required starting time to the
      computation time step. This functionality is implemented in the Device
      base class and, thus, available to all devices.

      Instead of specifying the start time of the generator as in
      test_iaf_dc_aligned_delay.sli, the emission time of the first current
      event is specified. A device can only take action in a step t-h -> t.
      When t-h represents the start time of the device, t is the earliest time
      stamp of an emitted event. In our case the time stamp is the onset of the
      current. Thus, both times can not simultaneously be independent of the
      computation time step h. It is sufficient to specify one of the two measures,
      the other one is computed automatically. Internally, only the start time
      is stored. A warning is issued when both measures are specified because
      a difference other than h would be meaningless and a difference of h may
      not be representable by the two double values. In case both properties are
      specified, on  overrides start. The timer of the device does not rely on
      computing differences between doubles but uses the exact representation of
      time provided by the simulation kernel.

      An inspection of the property dictionary of the DC generator at different
      computation step sizes shows the relationship between DC generator
      on and start.

      h=0.1ms	 h=0.5ms
      <<	 <<
      /start 1.9	 /start 1.5
      /on 2.0	 /on 2.0
      >>	 >>

      No output of the spike detector is visible here because of the short simulation
      time of only 6 ms. Set the simulation time to larger values to verify the
      consistency of voltage meter and spike detector.

      The expected output is documented at the end of the script.

      July 2004,
      updated, Diesmann

      Author:  February 2004, Diesmann, Gewaltig, Plesser

SeeAlso:

- testsuite::test_iaf_dc
- testsuite::test_iaf_dc_aligned
- testsuite::test_iaf_dc_aligned_delay

Source:

    /opt/conda/conda-bld/nest_1510212701067/work/nest-2.14.0/testsuite/unittests/test_iaf_dc_aligned_automatic.sli

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© 2004 The NEST Initiative