Command: testsuite::test_iaf_ps_dc_accuracy

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Name:
 testsuite::test_iaf_ps_dc_accuracy - test of accuracy of neuron models subject to DC current

Synopsis:
 (test_iaf_ps_dc_accuracy) run -> comparison with analytical solution

Description:

 A DC current is injected for a finite duration. The membrane potential at
 the end of the simulated interval is compared to the theoretical value for
 different computation step sizes.

 Computation step sizes are specified as base 2 values.

 Two different intervals are tested. At the end of the first interval the membrane
 potential still steeply increases. At the end of the second, the membrane 
 potential has within double precision already reached the limit for large t.

 The high accuracy of the neuron models is achieved by the use of Exact Integration [1]
 and an appropriate arrangement of the terms [2]. For small computation step sizes the 
 accuracy at large simulation time decreases because of the accumulation of errors.

 The expected output is documented at the end of the script.
 Individual simulation results can be inspected by uncommented the call 
 to function print_details.

Remarks:

 The script checks whether the kernel can be appropriately configured.
 The script can be used to check whether the accuracy has survived optimization
 by the C++ compiler.

 In case the accuracy is higher than specified by IEEE arithmetics this might
 be due to the use of processor registers. The compiler option   
 -ffloat-store of the gcc compiler ensures that doubles are not stored in 
 registers.

FirstVersion:
 May 2005
Author:
 March 2009, Diesmann
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] Morrison A, Straube S, Plesser H E, & Diesmann M (2007) Exact Subthreshold 
     Integration with Continuous Spike Times in Discrete Time Neural Network 
     Simulations. Neural Computation 19:47--79
SeeAlso:iaf_psc_alpha_canon iaf_psc_alpha_presc iaf_psc_delta_canon testsuite::test_iaf_ps_dc_t_accuracy
Source:
 /home/abuild/rpmbuild/BUILD/nest-2.4.1/testsuite/unittests/test_iaf_ps_dc_accuracy.sli

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