/// <inheritdoc/>
public void MutateWeight(EncogRandom rnd, NEATLinkGene linkGene,
double weightRange)
{
double delta = rnd.NextGaussian() * _sigma;
double w = linkGene.Weight + delta;
w = NEATPopulation.ClampWeight(w, weightRange);
linkGene.Weight = w;
}
/// <summary>
/// Called for each node in the progrmam. If this is a const node, then
/// mutate it according to the frequency and sigma specified.
/// </summary>
/// <param name="rnd">Random number generator.</param>
/// <param name="node">The node to mutate.</param>
private void MutateNode(EncogRandom rnd, ProgramNode node)
{
if (node.Template == StandardExtensions.EXTENSION_CONST_SUPPORT)
{
if (rnd.NextDouble() < _frequency)
{
ExpressionValue v = node.Data[0];
if (v.IsFloat)
{
double adj = rnd.NextGaussian()*_sigma;
node.Data[0] = new ExpressionValue(v.ToFloatValue()
+ adj);
}
}
}
foreach (ITreeNode n in node.ChildNodes)
{
var childNode = (ProgramNode) n;
MutateNode(rnd, childNode);
}
}
