/// <summary>
/// Calculates the total distance between two graphs, only
/// accounting for vertices.
/// </summary>
protected double TotalVertexDistance(IGraphChromosome g1, IGraphChromosome g2)
{
double nMismatch = 0;
double nMatch = 0;
double totalDist = 0;
foreach (var vert in g1.Vertices)
{
if (g2.ContainsVertex(vert.ID))
{
totalDist += VertexDistance(g2[vert.ID], vert.Value);
nMatch++;
}
else
{
nMismatch++;
}
}
foreach (var vert in g2.Vertices)
{
if (!g1.ContainsVertex(vert.ID))
{
nMismatch++;
}
}
int N = Math.Max(g1.VertexCount, g2.VertexCount);
return((VertexMismatchWeight * nMismatch / N) + (VertexMatchWeight * totalDist / nMatch));
}
protected override IGraphChromosome PerformCrossover(IGraphChromosome p1, IGraphChromosome p2)
{
IList <IChromosome> parents = new IChromosome[2];
// "Disjoint genes are inherited from the more fit parent."
var child = p1.Clone() as IGraphChromosome;
foreach (var vert in p1.Vertices)
{
if (p2.ContainsVertex(vert.ID))
{
parents[0] = vert.Value;
parents[1] = p2[vert.ID];
child[vert.ID] = VertexCrossover.Cross(parents)[0];
}
}
foreach (var edge in p1.Edges)
{
if (p2.ContainsEdge(edge.IDFrom, edge.IDTo))
{
parents[0] = edge.Value;
parents[1] = p2[edge.IDFrom, edge.IDTo];
child[edge.IDFrom, edge.IDTo] = EdgeCrossover.Cross(parents)[0];
}
}
return(child);
}