private static void Step(Dictionary <int, Vector> data, List <Cluster> clusters)
{
foreach (var cluster in clusters)
{
cluster.Points.Clear();
}
foreach (var point in data)
{
var distances = new List <Tuple <int, double> >();
for (var c = 0; c < clusters.Count; c++)
{
distances.Add(Tuple.Create(c, Euclidean.GetDistance(point.Value, clusters[c].Centroid)));
}
var bestDistance = distances.OrderBy(d => d.Item2).First();
clusters[bestDistance.Item1].Points.Add(point.Value);
}
foreach (var cluster in clusters)
{
if (cluster.Points.Count > 0)
{
cluster.Centroid = CalculateMean(cluster);
}
}
}
private static double SSE(List <Cluster> clusters)
{
foreach (var cluster in clusters)
{
foreach (var point in cluster.Points)
{
point.Distance = Euclidean.GetDistance(cluster.Centroid, point);
}
}
return(clusters.Select(c => c.Points.Select(p => Math.Pow(p.Distance.Value, 2)).Sum()).Average());
}