/*
 *  test_gamma_sup_generator.sli
 *
 *  This file is part of NEST.
 *
 *  Copyright (C) 2004 The NEST Initiative
 *
 *  NEST is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  NEST is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with NEST.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

 /* BeginDocumentation
Name: testsuite::test_gamma_sup_generator - sli script for test of gamma_sup_generator output 

Synopsis: (test_gamma_sup_generator) run -> compare spike train statistics with expectations


Description:
 
 test_gamma_sup_generator is a collection of tests which require basic 
 functionality of the generator. It tests
 1) if the firing rate of a superposition is close to the preset one.
 2) if the coefficient of variation of a superposition agrees with theory
 3) if the coefficient of variation of a single process agrees with theory
 4) if the spike trains generated for two different targets differ

 All of these tests are based on random number realizations, which is 
 necessarily so  since the model is stochastic. There is thus a finite 
 probability of test failure, even if everything is fine. The choice of the 
 variable err, which is the allowed relative deviation from the reference value, 
 can be used to make the test more or less strict. Increasing T inside the test 
 functions can also help to get more reliable statistics and a reduced 
 probability of false alarms.
 
 The values are chosen to have a reasonable execution time. False alarms were 
 never observed yet. Since random numbers are preserved through repetitions of
 the simulations, the test should work for sure as long as the random number 
 generation procedure of nest is not changed. If it is changed, failure of the
 test is still very unlikely.
 
 The intention of this script is to make sure that there are no gross errors in
 the main functions of the gamma_sup_generator. 

Remarks:
  This test script was adapted from test_ppd_sup_generator.sli  


Author:  June 2011, Moritz Deger
SeeAlso: gamma_sup_generator, testsuite::test_ppd_sup_generator
*/


/unittest (6688) require
/unittest using


0.2 /err Set


% 1) check for reasonable superposition spike rate
% 2) check if superposition cv agrees with theory

/check_sup_rate_and_cv
{    
   % test parameters
    5 /gamma_shape Set
    10.0 /rate Set
    10000.0 /T Set
    5 /n_proc Set
    1. /h Set

    ResetKernel
    
    << 
      /resolution  h
    >> /kernelparams Set
    
    0 kernelparams SetStatus 
    
    /gamma_sup_generator Create /psg Set

    <<
      /rate  rate
      /gamma_shape gamma_shape
      /n_proc n_proc
    >> /params Set
    
    psg params SetStatus
    
    /spike_detector Create /sd Set

    psg sd Connect
    T Simulate
    
    sd GetStatus /events get /times get /spikes Set

    % rate_sim = size(spikes) / (T*1e-3)
    spikes cva size T 1e-3 mul div /rate_sim Set /spikes_array Set

    % rate_ana = 1./(1./lam + d*1e-3)
    rate n_proc mul /rate_ana Set
    
    % ratio = rate_sim / rate_ana
    rate_sim rate_ana div /ratio Set
    
    % this could fail due to bad luck. However, if it passes once, then it should
    % always do so, since the random numbers are reproducible in NEST.
    1.0 err sub ratio lt
    ratio 1.0 err add lt
    and assert_or_die
    
    %isi = []
    %for i in xrange(1,len(spikes)):
    %    isi.append(spikes[i]-spikes[i-1])
    0.0 /t Set
    spikes cva { dup t sub exch /t Set  } Map /isi Set


    %# compute moments of ISI to get mean and variance
    %isi_m1 = 0. 
    %isi_m2 = 0.
    %for t in isi:
    %    isi_m1 += t
    %    isi_m2 += t**2
    0. /isi_m1 Set
    0. /isi_m2 Set
    isi { dup isi_m1 add /isi_m1 Set dup mul isi_m2 add /isi_m2 Set} forall
    
    %isi_mean = isi_m1 / len(isi)
    %isi_var = isi_m2/ len(isi) - isi_mean**2
    %cvsq = isi_var/isi_mean**2
    isi_m1 isi size exch pop div /isi_mean Set
    isi_m2 isi size exch pop div isi_mean dup mul sub /isi_var Set
    isi_var isi_mean 2 pow  div /cvsq_sim Set

    %theoretical CV**2 for PPD, should match gamma also, see Deger et al 2011, JCNS
    1.0 1.0 gamma_shape sqrt div sub /dbar Set
    1.0 rate div 1e3 mul /mu Set
    mu dbar mul /dead_time Set
    
    1.0 1.0 n_proc add div /cvfact1 Set
    n_proc 1.0 sub 2.0 1.0 dbar sub n_proc 1 add pow mul add /cvfact2 Set
    cvfact1 cvfact2 mul /cvsq_theo Set

    cvsq_sim cvsq_theo div /ratio_cvsq Set 
    1.0 err sub ratio_cvsq leq
    ratio_cvsq 1.0 err add leq
    and assert_or_die
    
} def



%3) check if single process respect isi moments

/check_single_rate_and_isi
{    
   % test parameters
    7 /gamma_shape Set
    15.0 /rate Set
    100000.0 /T Set
    1 /n_proc Set
    1.0 /h Set

    ResetKernel
    
    << 
      /resolution  h
    >> /kernelparams Set
    
    0 kernelparams SetStatus 
    
    /gamma_sup_generator Create /psg Set

    <<
      /rate  rate
      /gamma_shape gamma_shape
      /n_proc n_proc
    >> /params Set
    
    psg params SetStatus
    
    /spike_detector Create /sd Set
    
    psg sd Connect
    T Simulate
    
    sd GetStatus /events get /times get /spikes Set

    % rate_sim = size(spikes) / (T*1e-3)
    spikes cva size T 1e-3 mul div /rate_sim Set /spikes_array Set

    % rate_ana = 1./(1./lam + d*1e-3)
    rate n_proc mul /rate_ana Set
    
    % ratio = rate_sim / rate_ana
    rate_sim rate_ana div /ratio Set
    
    % this could fail due to bad luck. However, if it passes once, then it should
    % always do so, since the random numbers are reproducible in NEST.
    1.0 err sub ratio lt
    ratio 1.0 err add lt
    and assert_or_die
    
    %isi = []
    %for i in xrange(1,len(spikes)):
    %    isi.append(spikes[i]-spikes[i-1])
    % Assert that min(isi)>=d
    0.0 /t Set
    spikes cva { dup t sub exch /t Set  } Map /isi Set
%    isi Rest Min dead_time geq assert_or_die

    %# compute moments of ISI to get mean and variance
    %isi_m1 = 0. 
    %isi_m2 = 0.
    %for t in isi:
    %    isi_m1 += t
    %    isi_m2 += t**2
    0. /isi_m1 Set
    0. /isi_m2 Set
    isi { dup isi_m1 add /isi_m1 Set dup mul isi_m2 add /isi_m2 Set} forall
    
    %isi_mean = isi_m1 / len(isi)
    %isi_var = isi_m2/ len(isi) - isi_mean**2
    %cvsq = isi_var/isi_mean**2
    isi_m1 isi size exch pop div /isi_mean Set
    isi_m2 isi size exch pop div isi_mean dup mul sub /isi_var Set
    isi_var isi_mean 2 pow div /cvsq_sim Set

    %theoretical CV**2, see Deger et al 2011, JCNS
    % here we first match the equivalent PPD and then compute its CV**2
    % this is done because formulas are simpler to remember and code can
    % be reused.
    1.0 1.0 gamma_shape div sqrt sub /dbar Set
    1.0 rate div 1e3 mul /mu Set
    mu dbar mul /dead_time Set

    1.0 rate div /mu Set
    mu dead_time sub /lam Set
    1.0 lam div mu div 2 pow /cvsq_theo Set
    
    cvsq_sim cvsq_theo div /ratio_cvsq Set 
    1.0 err sub ratio_cvsq leq
    ratio_cvsq 1.0 err add leq
    and assert_or_die
    
} def


/check_different_outputs
   {

   % test parameters
    2 /gamma_shape Set
    25.0 /rate Set
    10.0 /T Set
    1000 /n_proc Set
    0.01 /h Set

    ResetKernel
    
    << 
      /resolution  h
    >> /kernelparams Set
    
    0 kernelparams SetStatus 
    
    /gamma_sup_generator Create /psg Set

    <<
      /rate  rate
      /gamma_shape gamma_shape
      /n_proc n_proc
    >> /params Set
    
    psg params SetStatus
    
    /spike_detector Create /sd1 Set
    /spike_detector Create /sd2 Set

    psg sd1 Connect
    psg sd2 Connect
    T Simulate

    %first we check if the spike trains are different
    [sd1 sd2] {[/events /times] get} forall  neq  % spike trains differ
    assert_or_die
    
    %and we also check the rates since we simulated anyway
    sd1 GetStatus /events get /times get /spikes1 Set
    sd2 GetStatus /events get /times get /spikes2 Set
    
    % rate_sim = size(spikes) / (T*1e-3)
    spikes1 cva size T 1e-3 mul div /rate_sim1 Set /spikes_array1 Set
    spikes2 cva size T 1e-3 mul div /rate_sim2 Set /spikes_array2 Set

    % rate_ana = 1./(1./lam + d*1e-3)
    rate n_proc mul /rate_ana Set
    
    % ratio = rate_sim / rate_ana
    rate_sim1 rate_ana div /ratio1 Set
    rate_sim2 rate_ana div /ratio2 Set
    
    % this could fail due to bad luck. However, if it passes once, then it should
    % always do so, since the random numbers are reproducible in NEST.
    1.0 err sub ratio1 lt
    ratio1 1.0 err add lt
    and assert_or_die
    
    1.0 err sub ratio2 lt
    ratio2 1.0 err add lt
    and assert_or_die
} def



check_sup_rate_and_cv
check_single_rate_and_isi
check_different_outputs