does k-means clusterer of apache commons math contains a means method?

Question

I have to get the means of a k-means clustering. currently I'm using the apache commons math library which implements a k-means plus plus clustering algorithm. do anybody know, if there is a simple way to get the means after the clustering with this library or have i to implement it by myself?
if not, can you explain me how to calculate it or give me a code example?

Answer 1

The output of the clustering algorithm must at least contain the cluster assignments, i.e. which cluster each point belongs to. If you have that, then the k-means clustering cluster centers are simply given by the mean of the points that belong to each cluster.

Answer 2

The KMeansPlusPlusClusterer (package org.apache.commons.math3.ml.clustering, version 3.2+ ) returns a List of CentroidCluster objects. From a CentroidCluster you can get the cluster center (= mean of cluster points) by calling the getCenter() method.