ODESystemBasedSpikingNeuron.cpp

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//
// C++ Implementation: ODESystemBasedSpikingNeuron
//
// Description:
//
//
// Author: Thomas Natschläger <tnatschl@lichtenberg>, (C) 2007
//
// Copyright: See COPYING file that comes with this distribution
//
//
#include "ODESystemBasedSpikingNeuron.h"
#include <iostream>

using std::cerr;
using std::endl;

ThreadSpecificRandomDistribution< NormalDistribution > ODESystemBasedSpikingNeuron::noise;

ODESystemBasedSpikingNeuron::ODESystemBasedSpikingNeuron( size_t dim ) : ODESystem( dim ) {
    solver = NULL;
}

int ODESystemBasedSpikingNeuron::init(InitializeInfo *ii) {
    // cerr << "ODESystemBasedSpikingNeuron::init( ): solver=" << solver << endl;
    setSystem( this );
    if( ! solver )
        solver = new odeiv::AdaptiveStepSolver( *this, odeiv::RungeKutta4() );
    //solver = new odeiv::FixedStepSolver( *this, odeiv::RungeKutta4() );
    return 0;
}

ODESystemBasedSpikingNeuron::~ODESystemBasedSpikingNeuron() {
    if( solver )
        delete solver;
}

int ODESystemBasedSpikingNeuron::reset( double dt, double *y0 ) {
        if( ! solver ) 
           init(NULL);
    SingleOutputSpikeSender::reset();
    nStepsInRefr = -1;         /* we are not refractory at the begining */
    clearSynapticInput();
    adjust( dt );
    solver->reset( dt, *this, y0 );
    Vm = y0[0];
    // cerr << "ODESystemBasedSpikingNeuron::reset( double dt, double *y0 ): " << y0[0]<< endl;
    return 0;
}

int ODESystemBasedSpikingNeuron::adjust( double dt ) {
    noise.set( NormalDistribution( 0.0, 1.0 ) );
    return 0;
}

int ODESystemBasedSpikingNeuron::advance( AdvanceInfo const &ai ) {

    I0 = Em / Rm + Isyn + Iinject;
    G0 = 1.0 / Rm + Gsyn;

    if ( Inoise > 0.0 ) {
        I0 += ( noise() * Inoise );
    }

    solver->advance( ai.t.in_sec(), ai.dt.in_sec(), *this );
    copySolverStateToFields();
    Vm = solver->y(0);
    
    bool hasFired = false;

    if ( ( ( --nStepsInRefr ) <= 0 ) && ( Vm >= Vthresh ) ) {
        // Note that the neuron has fired!
        hasFired = true;
        // calc number of steps how long we are refractory
        nStepsInRefr = ( int )( Trefract / ai.dt.in_sec() ) - 1;
    }

    // clear synaptic input for next time step
    clearSynapticInput();

    // Return proper value
    if ( hasFired ) {
        out_port.setSpike( ai );
        return ADVANCEFLAG_HASSPIKED;
    } else {
        return 0;
    }
}

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