public IPoints RunClusterAlgo(ClusterInfo clusterInfo)
{
// Skip points outside the grid
IPoints filtered = clusterInfo.IsFilterData ? FilterDataset(Dataset, Grid) : Dataset;
// Put points in buckets
foreach (var p in filtered.Data)
{
var idxy = GetPointMappedIds(p, Grid, DeltaX, DeltaY);
var idx = idxy[0];
var idy = idxy[1];
// Bucket id
var id = GetId(idx, idy);
// Bucket exists, add point
if (BucketsLookup.ContainsKey(id))
{
BucketsLookup[id].Points.Add(p);
}
// New bucket, create and add point
else
{
var bucket = new Bucket(idx, idy, id);
bucket.Points.Add(p);
BucketsLookup.Add(id, bucket);
}
}
// Calculate centroid for all buckets
SetCentroidForAllBuckets(BucketsLookup.Values);
// Merge if gridpoint is to close
if (AlgoConfig.DoMergeGridIfCentroidsAreCloseToEachOther) MergeClustersGrid();
if (AlgoConfig.DoUpdateAllCentroidsToNearestContainingPoint) UpdateAllCentroidsToNearestContainingPoint();
// Check again
// Merge if gridpoint is to close
if (AlgoConfig.DoMergeGridIfCentroidsAreCloseToEachOther
&& AlgoConfig.DoUpdateAllCentroidsToNearestContainingPoint)
{
MergeClustersGrid();
// And again set centroid to closest point in bucket
UpdateAllCentroidsToNearestContainingPoint();
}
return GetClusterResult(Grid);
}
// Update centroid location to nearest point,
// e.g. if you want to show cluster point on a real existing point area
// O(n)
public void UpdateCentroidToNearestContainingPoint(Bucket bucket)
{
if (bucket == null || bucket.Centroid == null ||
bucket.Points == null || bucket.Points.Count == 0)
{
return;
}
var closest = GetClosestPoint(bucket.Centroid, bucket.Points);
bucket.Centroid.X = closest.X; // no normalize, points are already normalized by default
bucket.Centroid.Y = closest.Y;
}