docs: public double[] toClusterCenter() {
  		double[] output = new double[this.sumPoints.length + 1];
  		System.arraycopy(this.sumPoints, 0, output, 1, this.sumPoints.length);
  		output[0] = this.numPoints;
  		for (int i = 1; i < output.length; i++) {
  			output[i] /= this.numPoints;
  		}
  		return output;
  	}