getLinkage method

double getLinkage(List<int> cluster1, List<int> cluster2)

Calculate linkage between 2 clusters

Clusters contains index of dataset

Implementation

double getLinkage(List<int> cluster1, List<int> cluster2) {
  String hash = cluster1.length > cluster2.length
      ? "$cluster1-$cluster2"
      : "$cluster2-$cluster1";

  if (_cache.containsKey(hash)) return _cache[hash]!;

  List<double> distanceList = [];

  for (int i = 0; i < cluster1.length; i++) {
    for (int j = 0; j < cluster2.length; j++) {
      //get dataset index from the cluster
      distanceList.add(getDistance(cluster1[i], cluster2[j]));
    }
  }

  return _cache[hash] = linkageMeasure!(distanceList);
}