void
nest::pp_psc_delta::update( Time const& origin, const long_t from, const long_t to )
{
assert( to >= 0 && ( delay ) from < kernel().connection_builder_manager.get_min_delay() );
assert( from < to );
for ( long_t lag = from; lag < to; ++lag )
{
S_.y3_ = V_.P30_ * ( S_.y0_ + P_.I_e_ ) + V_.P33_ * S_.y3_ + B_.spikes_.get_value( lag );
double_t q_temp_ = 0;
for ( uint_t i = 0; i < S_.q_elems_.size(); i++ )
{
S_.q_elems_[ i ] = V_.Q33_[ i ] * S_.q_elems_[ i ];
q_temp_ += S_.q_elems_[ i ];
}
S_.q_ = q_temp_;
if ( S_.r_ == 0 )
{
// Neuron not refractory
// Calculate instantaneous rate from transfer function:
// rate = c1 * y3' + c2 * exp(c3 * y3')
// Adaptive threshold leads to effective potential V_eff instead of y3
double_t V_eff;
V_eff = S_.y3_ - S_.q_;
double_t rate = ( P_.c_1_ * V_eff + P_.c_2_ * std::exp( P_.c_3_ * V_eff ) );
if ( rate > 0.0 )
{
ulong_t n_spikes = 0;
if ( P_.dead_time_ > 0.0 )
{
// Draw random number and compare to prob to have a spike
if ( V_.rng_->drand() <= -numerics::expm1( -rate * V_.h_ * 1e-3 ) )
{
n_spikes = 1;
}
}
else
{
// Draw Poisson random number of spikes
V_.poisson_dev_.set_lambda( rate * V_.h_ * 1e-3 );
n_spikes = V_.poisson_dev_.ldev( V_.rng_ );
}
if ( n_spikes > 0 ) // Is there a spike? Then set the new dead time.
{
// Set dead time interval according to paramters
if ( P_.dead_time_random_ )
{
S_.r_ = Time( Time::ms( V_.gamma_dev_( V_.rng_ ) / V_.dt_rate_ ) ).get_steps();
}
else
S_.r_ = V_.DeadTimeCounts_;
for ( uint_t i = 0; i < S_.q_elems_.size(); i++ )
{
S_.q_elems_[ i ] += P_.q_sfa_[ i ] * n_spikes;
}
// And send the spike event
SpikeEvent se;
se.set_multiplicity( n_spikes );
kernel().event_delivery_manager.send( *this, se, lag );
// set spike time for STDP to work,
// see https://github.com/nest/nest-simulator/issues/77
for ( uint_t i = 0; i < n_spikes; i++ )
{
set_spiketime( Time::step( origin.get_steps() + lag + 1 ) );
}
// Reset the potential if applicable
if ( P_.with_reset_ )
{
S_.y3_ = 0.0;
}
} // S_.y3_ = P_.V_reset_;
} // if (rate > 0.0)
}
else // Neuron is within dead time
{
--S_.r_;
}
// Set new input current
S_.y0_ = B_.currents_.get_value( lag );
// Voltage logging
B_.logger_.record_data( origin.get_steps() + lag );
}
}
void
nest::pp_pop_psc_delta::update( Time const& origin, const long_t from, const long_t to )
{
assert( to >= 0 && ( delay ) from < kernel().connection_builder_manager.get_min_delay() );
assert( from < to );
for ( long_t lag = from; lag < to; ++lag )
{
S_.h_ = S_.h_ * V_.P33_ + V_.P30_ * ( S_.y0_ + P_.I_e_ ) + B_.spikes_.get_value( lag );
// get_thetas_ages
std::vector< double_t > tmp_vector;
double_t integral = 0;
tmp_vector.clear();
for ( uint_t i = 0; i < V_.eta_kernel_.size(); i++ )
{
tmp_vector.push_back( V_.eta_kernel_[ i ]
* S_.n_spikes_past_[ ( S_.p_n_spikes_past_ + i ) % S_.n_spikes_past_.size() ] * V_.h_
* 0.001 );
integral += tmp_vector[ i ];
}
S_.thetas_ages_.clear();
S_.thetas_ages_.push_back( integral );
for ( uint_t i = 1; i < V_.eta_kernel_.size(); i++ )
S_.thetas_ages_.push_back( S_.thetas_ages_[ i - 1 ] - tmp_vector[ i - 1 ] );
for ( uint_t i = 0; i < V_.eta_kernel_.size(); i++ )
S_.thetas_ages_[ i ] += V_.theta_kernel_[ i ];
S_.thetas_ages_.push_back( 0 );
// get_escape_rate
for ( uint_t i = 0; i < S_.rhos_ages_.size(); i++ )
S_.rhos_ages_[ i ] = P_.rho_0_ * std::exp( ( S_.h_ + S_.thetas_ages_[ i ] ) / P_.delta_u_ );
double p_argument;
// generate_spikes
for ( uint_t i = 0; i < S_.age_occupations_.size(); i++ )
{
if ( S_.age_occupations_[ ( S_.p_age_occupations_ + i ) % S_.age_occupations_.size() ] > 0 )
{
p_argument = -numerics::expm1( -S_.rhos_ages_[ i ] * V_.h_
* 0.001 ); // V_.h_ is in ms, S_.rhos_ages_ is in Hz
if ( p_argument > V_.min_double_ )
{
V_.binom_dev_.set_p_n( p_argument,
S_.age_occupations_[ ( S_.p_age_occupations_ + i ) % S_.age_occupations_.size() ] );
S_.n_spikes_ages_[ i ] = V_.binom_dev_.ldev( V_.rng_ );
}
else
{
S_.n_spikes_ages_[ i ] = 0;
}
}
else
S_.n_spikes_ages_[ i ] = 0;
}
S_.p_n_spikes_past_ = ( S_.p_n_spikes_past_ - 1 + S_.n_spikes_past_.size() )
% S_.n_spikes_past_.size(); // shift to the right
int_t temp_sum = 0;
for ( uint_t i = 0; i < S_.n_spikes_ages_.size(); i++ ) // cumulative sum
temp_sum += S_.n_spikes_ages_[ i ];
S_.n_spikes_past_[ S_.p_n_spikes_past_ ] = temp_sum;
// update_age_occupations
for ( uint_t i = 0; i < S_.age_occupations_.size(); i++ )
S_.age_occupations_[ ( S_.p_age_occupations_ + i ) % S_.age_occupations_.size() ] -=
S_.n_spikes_ages_[ i ];
int_t last_element_value =
S_.age_occupations_[ ( S_.p_age_occupations_ - 1 + S_.age_occupations_.size() )
% S_.age_occupations_.size() ]; // save the last element
S_.p_age_occupations_ = ( S_.p_age_occupations_ - 1 + S_.age_occupations_.size() )
% S_.age_occupations_.size(); // shift to the right
S_.age_occupations_[ ( S_.p_age_occupations_ - 1 + S_.age_occupations_.size() )
% S_.age_occupations_.size() ] += last_element_value;
S_.age_occupations_[ S_.p_age_occupations_ ] = S_.n_spikes_past_[ S_.p_n_spikes_past_ ];
// Set new input current
S_.y0_ = B_.currents_.get_value( lag );
// Voltage logging
B_.logger_.record_data( origin.get_steps() + lag );
// test if S_.n_spikes_past_[S_.p_n_spikes_past_]!=0, generate spike and send this number as the
// parameter
if ( S_.n_spikes_past_[ S_.p_n_spikes_past_ ] > 0 ) // Is there any spike?
{
SpikeEvent se;
se.set_multiplicity( S_.n_spikes_past_[ S_.p_n_spikes_past_ ] );
kernel().event_delivery_manager.send( *this, se, lag );
}
}
}