//Constructor
/// <summary>
/// Creates initialized instance
/// </summary>
/// <param name="sourceNeuron">Source neuron</param>
/// <param name="targetNeuron">Target neuron</param>
/// <param name="weight">Synapse initial weight</param>
public BaseSynapse(INeuron sourceNeuron,
INeuron targetNeuron,
double weight
)
{
//Neurons to be connected
SourceNeuron = sourceNeuron;
TargetNeuron = targetNeuron;
//Euclidean distance
Distance = EuclideanDistance.Compute(SourceNeuron.Placement.ReservoirCoordinates, TargetNeuron.Placement.ReservoirCoordinates);
//Weight sign rules
if (SourceNeuron.Role == NeuronCommon.NeuronRole.Input)
{
if (TargetNeuron.TypeOfActivation == ActivationType.Analog)
{
//No change of the weight sign
Weight = weight;
}
else
{
//Target is spiking neuron
//Weight must be always positive
Weight = Math.Abs(weight);
}
}
else
{
//Weight sign is dependent on source neuron role
Weight = Math.Abs(weight) * (SourceNeuron.Role == NeuronCommon.NeuronRole.Excitatory ? 1d : -1d);
}
//Efficacy statistics
EfficacyStat = new BasicStat(false);
return;
}
//Constructor
/// <summary>
/// Creates initialized instance
/// </summary>
/// <param name="sourceNeuron">Source neuron</param>
/// <param name="targetNeuron">Target neuron</param>
/// <param name="weight">Synapse weight</param>
public BaseSynapse(INeuron sourceNeuron,
INeuron targetNeuron,
double weight
)
{
//Neurons to be connected
SourceNeuron = sourceNeuron;
TargetNeuron = targetNeuron;
//Euclidean distance
Distance = EuclideanDistance.Compute(SourceNeuron.Placement.ReservoirCoordinates, TargetNeuron.Placement.ReservoirCoordinates);
//Weight sign and signal range conversion rules
if (SourceNeuron.Role == CommonEnums.NeuronRole.Input)
{
//Source is input neuron
if (TargetNeuron.OutputType == CommonEnums.NeuronSignalType.Spike)
{
//Target is spiking
//Ensure positive weight
Weight = Math.Abs(weight);
//Convert signal to <0,1>
_add = -SourceNeuron.OutputRange.Min;
_div = SourceNeuron.OutputRange.Span;
}
else
{
//Target is also analog
//Weight is unchanged
Weight = weight;
//No signal conversion
_add = 0;
_div = 1;
}
}
else
{
//Source is reservoir neuron
if (SourceNeuron.OutputType == CommonEnums.NeuronSignalType.Spike)
{
//Source reservoir neuron is spiking
if (TargetNeuron.OutputType == CommonEnums.NeuronSignalType.Spike)
{
//Target is also spiking
//Weight dependent on source neuron role
Weight = Math.Abs(weight) * ((SourceNeuron.Role == CommonEnums.NeuronRole.Excitatory) ? 1 : -1);
//No signal conversion
_add = 0;
_div = 1;
}
else
{
//Target is analog
//Weight is unchanged
Weight = weight;
//Convert signal to target neuron range
_add = (TargetNeuron.OutputRange.Min - SourceNeuron.OutputRange.Min);
_div = (SourceNeuron.OutputRange.Span / TargetNeuron.OutputRange.Span);
}
}
else
{
//Source reservoir neuron is analog
if (TargetNeuron.OutputType == CommonEnums.NeuronSignalType.Spike)
{
//Target is spiking
//Weight dependent on source neuron role
Weight = Math.Abs(weight) * ((SourceNeuron.Role == CommonEnums.NeuronRole.Excitatory) ? 1 : -1);
//Convert signal to <0,1>
_add = -SourceNeuron.OutputRange.Min;
_div = SourceNeuron.OutputRange.Span;
}
else
{
//Target is also analog
//Weight is unchanged
Weight = weight;
//No signal conversion
_add = 0;
_div = 1;
}
}
}
//Set Delay to 0 as default. It can be changed later by SetDelay method.
Delay = 0;
//Efficacy statistics
EfficacyStat = new BasicStat(false);
return;
}
//Constructor
/// <summary>
/// Creates initialized instance
/// </summary>
/// <param name="sourceNeuron">Source neuron</param>
/// <param name="targetNeuron">Target neuron</param>
/// <param name="role">Synapse role</param>
/// <param name="synapseCfg">Synapse general configuration</param>
/// <param name="rand">Random object</param>
public Synapse(INeuron sourceNeuron,
INeuron targetNeuron,
SynRole role,
SynapseSettings synapseCfg,
Random rand
)
{
//Neurons to be connected
SourceNeuron = sourceNeuron;
TargetNeuron = targetNeuron;
//Synapse role
Role = role;
//Euclidean distance
Distance = EuclideanDistance.Compute(SourceNeuron.Location.ReservoirCoordinates, TargetNeuron.Location.ReservoirCoordinates);
//The rest
_efficacyComputer = null;
if (TargetNeuron.TypeOfActivation == ActivationType.Spiking)
{
//Spiking target
if (Role == SynRole.Input)
{
DelayMethod = synapseCfg.SpikingTargetCfg.InputSynCfg.DelayMethod;
_maxDelay = synapseCfg.SpikingTargetCfg.InputSynCfg.MaxDelay;
if (SourceNeuron.TypeOfActivation == ActivationType.Analog)
{
//Analog source
Weight = rand.NextDouble(synapseCfg.SpikingTargetCfg.InputSynCfg.AnalogSourceCfg.WeightCfg);
}
else
{
//Spiking source
Weight = rand.NextDouble(synapseCfg.SpikingTargetCfg.InputSynCfg.SpikingSourceCfg.WeightCfg);
_efficacyComputer = PlasticityCommon.GetEfficacyComputer(SourceNeuron,
synapseCfg.SpikingTargetCfg.InputSynCfg.SpikingSourceCfg.PlasticityCfg.DynamicsCfg
);
}
}
else if (Role == SynRole.Excitatory)
{
DelayMethod = synapseCfg.SpikingTargetCfg.ExcitatorySynCfg.DelayMethod;
_maxDelay = synapseCfg.SpikingTargetCfg.ExcitatorySynCfg.MaxDelay;
if (SourceNeuron.TypeOfActivation == ActivationType.Analog)
{
//Analog source
Weight = rand.NextDouble(synapseCfg.SpikingTargetCfg.ExcitatorySynCfg.AnalogSourceCfg.WeightCfg);
}
else
{
//Spiking source
Weight = rand.NextDouble(synapseCfg.SpikingTargetCfg.ExcitatorySynCfg.SpikingSourceCfg.WeightCfg);
_efficacyComputer = PlasticityCommon.GetEfficacyComputer(SourceNeuron,
synapseCfg.SpikingTargetCfg.ExcitatorySynCfg.SpikingSourceCfg.PlasticityCfg.DynamicsCfg
);
}
}
else if (Role == SynRole.Inhibitory)
{
DelayMethod = synapseCfg.SpikingTargetCfg.InhibitorySynCfg.DelayMethod;
_maxDelay = synapseCfg.SpikingTargetCfg.InhibitorySynCfg.MaxDelay;
if (SourceNeuron.TypeOfActivation == ActivationType.Analog)
{
//Analog source
Weight = -rand.NextDouble(synapseCfg.SpikingTargetCfg.InhibitorySynCfg.AnalogSourceCfg.WeightCfg);
}
else
{
//Spiking source
Weight = -rand.NextDouble(synapseCfg.SpikingTargetCfg.InhibitorySynCfg.SpikingSourceCfg.WeightCfg);
_efficacyComputer = PlasticityCommon.GetEfficacyComputer(SourceNeuron,
synapseCfg.SpikingTargetCfg.InhibitorySynCfg.SpikingSourceCfg.PlasticityCfg.DynamicsCfg
);
}
}
else
{
throw new ArgumentException($"Invalid synapse role {role}.", "role");
}
}
else
{
//Analog target
if (Role == SynRole.Input)
{
DelayMethod = synapseCfg.AnalogTargetCfg.InputSynCfg.DelayMethod;
_maxDelay = synapseCfg.AnalogTargetCfg.InputSynCfg.MaxDelay;
if (SourceNeuron.TypeOfActivation == ActivationType.Analog)
{
//Analog source
Weight = rand.NextDouble(synapseCfg.AnalogTargetCfg.InputSynCfg.AnalogSourceCfg.WeightCfg);
}
else
{
//Spiking source
Weight = rand.NextSign() * rand.NextDouble(synapseCfg.AnalogTargetCfg.InputSynCfg.SpikingSourceCfg.WeightCfg);
_efficacyComputer = PlasticityCommon.GetEfficacyComputer(SourceNeuron,
synapseCfg.AnalogTargetCfg.InputSynCfg.SpikingSourceCfg.PlasticityCfg.DynamicsCfg
);
}
}
else if (Role == SynRole.Indifferent)
{
DelayMethod = synapseCfg.AnalogTargetCfg.IndifferentSynCfg.DelayMethod;
_maxDelay = synapseCfg.AnalogTargetCfg.IndifferentSynCfg.MaxDelay;
if (SourceNeuron.TypeOfActivation == ActivationType.Analog)
{
//Analog source
Weight = rand.NextSign() * rand.NextDouble(synapseCfg.AnalogTargetCfg.IndifferentSynCfg.AnalogSourceCfg.WeightCfg);
}
else
{
//Spiking source
Weight = rand.NextSign() * rand.NextDouble(synapseCfg.AnalogTargetCfg.IndifferentSynCfg.SpikingSourceCfg.WeightCfg);
_efficacyComputer = PlasticityCommon.GetEfficacyComputer(SourceNeuron,
synapseCfg.AnalogTargetCfg.IndifferentSynCfg.SpikingSourceCfg.PlasticityCfg.DynamicsCfg
);
}
}
else
{
throw new ArgumentException($"Invalid synapse role {role}.", "role");
}
}
//Source neuron - output data and signal index
_sourceNeuronOutputData = SourceNeuron.OutputData;
_analogSourceSignal = TargetNeuron.TypeOfActivation == ActivationType.Analog;
//Efficacy statistics
EfficacyStat = new BasicStat(false);
Reset(true);
return;
}