D:/Home/Programs/iSpike/src/NeuronSim/IzhikevichNeuronSim.cpp

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#include <iSpike/NeuronSim/IzhikevichNeuronSim.hpp>
#include <iSpike/ISpikeException.hpp>
#include <iSpike/Log/Log.hpp>

#include <algorithm>

using namespace ispike;


IzhikevichNeuronSim::IzhikevichNeuronSim() :
        numNeurons(0),
        aParam(0.1),
        bParam(0.2),
        cParam(-65.0),
        dParam(2.0)
{
        ;
}


IzhikevichNeuronSim::IzhikevichNeuronSim(size_t numNeurons,
                double a, double b, double c, double d) :
        numNeurons(numNeurons),
        aParam(a),
        bParam(b),
        cParam(c),
        dParam(d),
        vArray(numNeurons, c),
        uArray(numNeurons, b*c),
        iArray(numNeurons, 0.0),
        firedArray(numNeurons, false)
{
        ;
}



/*--------------------------------------------------------------------*/
/*---------                 PUBLIC METHODS                     -------*/
/*--------------------------------------------------------------------*/

void IzhikevichNeuronSim::initialize(size_t numNeurons){

        LOG(LOG_DEBUG)<<"Initializing neuron simulator with "<<numNeurons<<" neurons.";
        this->numNeurons = numNeurons;

        vArray.clear();
        uArray.clear();
        iArray.clear();
        firedArray.clear();

        vArray.resize(numNeurons, cParam);
        uArray.resize(numNeurons, bParam * cParam);
        iArray.resize(numNeurons, 0.0);
        firedArray.resize(numNeurons, false);
}


void IzhikevichNeuronSim::setInputCurrent(unsigned index, double current){
        if(index >= numNeurons) {
                throw ISpikeException("IzhikevichNeuronSim: Index is out of range.");
        }
        iArray[index] = current;
}


void IzhikevichNeuronSim::step(){

        //Clear spikes and fired array
        spikeVector.clear();
        std::fill(firedArray.begin(), firedArray.end(), false);

        //Calculate state of neurons
        for(unsigned n = 0; n < numNeurons; ++n) {
                for(unsigned t=0; t<4; ++t) {
                        if(!firedArray[n]) {
                                vArray[n] += 0.25 * ((0.04* vArray[n] + 5.0) * vArray[n] + 140.0 - uArray[n] + iArray[n]);
                                uArray[n] += 0.25 * (aParam * (bParam * vArray[n] - uArray[n]));
                                firedArray[n] = vArray[n] >= 30.0;
                        }
                }
                iArray[n] = 0.0;

                //Neuron has fired -add spike to buffer
                if(firedArray[n]) {
                        vArray[n] = cParam;
                        uArray[n] += dParam;
                        spikeVector.push_back(n);
                }
        }
}