Controller.cs

using UnityEngine;
using System.Collections;
using System.Collections.Generic;
using Accord.MachineLearning.Structures;

public class Controller : MonoBehaviour {

	private readonly Dictionary<Vector3, Informer> map = new Dictionary<Vector3, Informer>();

	private readonly KDTree<Informer> tree = new KDTree<Informer> (); 

	public void RegisterInformer(Informer informer) {
		var position = informer.transform.position;
		map.Add (position, informer);
		Debug.Log ("Informer added at: " + position);

		tree.Add (position, informer);
	}
}