(ns code.learners.kmeans.k_means_classifier
  (:use (code.utils utils)) 
  (:use (incanter core)))

;return nearest cluster

(defn find-nearest-cluster [one clusters dist]
  (let [cluster-centroids (map #(centroid %) clusters)	
        cluster-w-centroids (map #(vector %1 %2) cluster-centroids clusters)
        nearest-cluster-centroid (second 
        												 	(first 
        												 		(sort-by 
        												 			first 
        												 				(map #(vector (dist one %) %) 
        												 					cluster-centroids))))
        nearest-cluster (second 
        									(first 
        										(filter #(= nearest-cluster-centroid 
        																(first %)) 
        											cluster-w-centroids)))]
    nearest-cluster))

;classify one test

(defn k-means-classifier [one clusters dist]
  (let [nearest-cluster (find-nearest-cluster one clusters dist)]
   (if (= (nrow nearest-cluster) 1) (last nearest-cluster)
       (let [kn (+ 1 (int (Math/sqrt (nrow nearest-cluster))))
             k-nearest (map 
             					 	second 
             					 		(take kn 
             					 					(sort-by 
             					 						first 
             					 							(map #(vector (dist one %) %) 
             					 								nearest-cluster))))
             klass (last (Transpose k-nearest))
             classification (k-majority klass)]
         classification))))