# Command: testsuite::test_iaf_psp_normalized

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Name:

    testsuite::test_iaf_psp_normalized - check if PSP can be normalized

Synopsis:

    (test_iaf_psp_normalized) run -> compare response with desired outcome

Description:

      The script computes the peak location of the PSP analytically for a
      neuron model with an alpha-shaped post-synaptic current (PSC) [1]. In case
      the GNU Scientific Library (GSL) is not present the peak location is
      found by searching for the root of the derivative of the PSP. We then
      compute the peak value for a PSC with unit amplitude and show how the
      synaptic weight can be adjusted to cause a PSP of a specific
      amplitiude. Finally, we check whether the simulation indeed generates
      a PSP of the desired amplitude.

      In application code the test for the availability of the GSL is not
      necessary because NEST has a built in version of the LambertWm1 which
      automatically replaces the GSL function if required. This removes the
      need to specify the derivative of the function of interest, here the
      PSP, in application code.  A further alternative is used in
      test_lambertw where knowledge of the range of values of the
      non-principal branch of the Lambert-W function [-1,-\infty) is
      exploited to find the inverse of x*exp(x) by bisectioning.

References:

      [1] Rotter S & Diesmann M (1999) Exact simulation of time-invariant linear
      systems with applications to neuronal modeling. Biologial Cybernetics
      81:381-402.
      [2] Galassi, M., Davies, J., Theiler, J., Gough, B., Jungman, G., Booth, M.,
      & Rossi, F. (2006). GNU Scientific Library Reference Manual (2nd Ed.).
      Network Theory Limited.

      Author:  July 2009, Diesmann

SeeAlso:

- testsuite::test_iaf_psp_peak
- testsuite::test_iaf_psp
- testsuite::test_lambertw
- LambertWm1

Source:

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

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