func randomNonRecurrentOutbound(neuron *ng.Neuron) *ng.OutboundConnection {
for i := 0; i < len(neuron.Outbound); i++ {
randIndex := RandomIntInRange(0, len(neuron.Outbound))
outbound := neuron.Outbound[randIndex]
if neuron.IsConnectionRecurrent(outbound) {
continue
} else {
return outbound
}
}
return nil
}
func NeuronRemoveBias(neuron *ng.Neuron) (bool, MutateResult) {
if neuron.Bias != 0 {
neuron.Bias = 0
return true, nil
}
return false, nil
}
func NeuronAddBias(neuron *ng.Neuron) (bool, MutateResult) {
if neuron.Bias == 0 {
neuron.Bias = RandomBias()
return true, nil
}
return false, nil
}
func possiblyPerturbBias(neuron *ng.Neuron, probability float64, saturationBounds []float64) bool {
didPerturb := false
if rand.Float64() < probability {
bias := neuron.Bias
perturbedBias := perturbParameter(bias, saturationBounds)
neuron.Bias = perturbedBias
logg.LogTo("DEBUG", "bias %v -> %v", bias, perturbedBias)
didPerturb = true
}
return didPerturb
}
func verifyWeightsModified(neuron, neuronCopy *ng.Neuron) bool {
foundModifiedWeight := false
// make sure the weights have been modified for at least
// one of the inbound connections
originalInboundMap := neuron.InboundUUIDMap()
copyInboundMap := neuronCopy.InboundUUIDMap()
for uuid, connection := range originalInboundMap {
connectionCopy := copyInboundMap[uuid]
for i, weight := range connection.Weights {
weightCopy := connectionCopy.Weights[i]
if weight != weightCopy {
foundModifiedWeight = true
break
}
}
}
return foundModifiedWeight
}
func neuronAddInlinkFrom(neuron *ng.Neuron, sourceNodeId *ng.NodeId) *ng.InboundConnection {
cortex := neuron.Cortex
// create weight vector
weightVectorLength := 1
if sourceNodeId.NodeType == ng.SENSOR {
sensor := cortex.FindSensor(sourceNodeId)
weightVectorLength = sensor.VectorLength
}
weights := randomWeights(weightVectorLength)
// make an inbound connection sourceNodeId <- neuron
connection := neuron.ConnectInboundWeighted(sourceNodeId, weights)
// make an outbound connection sourceNodeId -> neuron
chosenConnector := cortex.FindConnector(sourceNodeId)
ng.ConnectOutbound(chosenConnector, neuron)
return connection
}
func NeuronMutateActivation(neuron *ng.Neuron) (bool, MutateResult) {
encodableActivations := ng.AllEncodableActivations()
for i := 0; i < 100; i++ {
// pick a random activation function from list
randomIndex := ng.RandomIntInRange(0, len(encodableActivations))
chosenActivation := encodableActivations[randomIndex]
// if we chose a different activation than current one, use it
if chosenActivation.Name != neuron.ActivationFunction.Name {
neuron.ActivationFunction = chosenActivation
return true, nil
}
}
// if we got this far, something went wrong
return false, nil
}