code: protected void updateClusterCenters() {
  		// compute the new centers of each cluster
  		for (int i = 0; i < clusters.size; i++) {
  			double mc = memberCount.get(i);
  			double[] w = workClusters.get(i);
  			double[] c = clusters.get(i);
  
  			for (int j = 0; j < w.length; j++) {
  				c[j] = w[j] / mc;
  			}
  		}
  	}
docs: Sets the location of each cluster to the average location of all its members.