Func <double, double> NodeFunc(NodeGene nodeGene)
{
switch (nodeGene.FunctionType)
{
case FunctionType.Identity:
return(x => x);
case FunctionType.Heaviside:
return(x => x > 0 ? 1 : 0);
case FunctionType.Sigmoid:
return(x => 1 / (1 + Exp(-4.9 * x)));
case FunctionType.Sin:
return(Sin);
case FunctionType.Exponent:
return(Exp);
case FunctionType.Log:
return(x => x <= 0 ? 0 : Log(x));
}
throw new ArgumentException();
}
public Chromosome MutateAddNode(
Func <int, int> chooseEdgeGeneTypeIndex,
NodeGene newNodeGene
) =>
Change((e, n) => {
var enabledEdges = EdgeGenes.Where(edge => edge.Value.IsEnabled).Select(edge => edge.Key).ToImmutableList();
if (enabledEdges.Count == 0)
{
return;
}
var edgeGeneType = enabledEdges.ElementAt(chooseEdgeGeneTypeIndex(enabledEdges.Count));
var edgeGene = EdgeGenes[edgeGeneType];
e[edgeGeneType] = edgeGene.Disable();
var newNodeGeneType = new NodeGeneType(NodeGeneType.InnovationIdByParents(edgeGeneType.From, edgeGeneType.To, newNodeGene));
n[newNodeGeneType] = newNodeGene;
e[new EdgeGeneType(edgeGeneType.From, newNodeGeneType)] = new EdgeGene(1, true);
e[new EdgeGeneType(newNodeGeneType, edgeGeneType.To)] = new EdgeGene(edgeGene.Weight, true);
});
public static string InnovationIdByParents(NodeGeneType a, NodeGeneType b, NodeGene nodeGene) => Hash(a.InnovationId + b.InnovationId + nodeGene.GetHashCode());