Name: testsuite::test_spike_poisson_ps - tests if spikes independent of resolution

Synopsis:

(test_spike_poisson_ps) run -&gt; compare with results at other resolutions


Description:

The difference in spike times is exactly 0.0 between 
all resolutions. 
test_spike_poisson_ps_precision.sli 
already verified that spikes are produced and recorded with 
double resolution. 
This script will give identical results almost always, even if the resolution 
is not representable as a double. The main reason for this is that the 
poisson_generator_ps generates spikes without attention to resolution. This 
means that exactly the same sequence of spike times is generated internally 
in the generator independent of resolution. Rounding errors occur, if at all, 
only when the spike time is split into a multiple of the resolution and the 
offset. In this calculation, the resolution enters as a fixed multiple of tics. 
The calculation is reversed in the spike detector, when step-multiple and offset 
are recombined. This splitting and recombination apparently gives reproducible 
results. The only deviation observed was for two spikes at very early times (&lt;0.01 ms) 
and coarse resolution (0.1 ms); total of 388.533 spikes tested. Therefore I 
introduced the check against the 1e-15 relative error limit below. 
If this test fails go back to 
test_spike_poisson_ps_precision.sli 
to check whether poisson_generator_ps can emit spike times at 
double precision or whether spike times are limited to the 
precision of a tic.


Author:

Plesser, Diesmann


FirstVersion:

February 2007


Source:

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