Name: testsuite::test_iaf_psp_normalized - check if PSP can be normalized

Synopsis:

(test_iaf_psp_normalized) run -&gt; 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 &amp; 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., 
&amp; 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:

/var/www/debian/nest/nest-simulator-2.20.0/testsuite/unittests/test_iaf_psp_normalized.sli
