/**
* 执行KNN算法，获取测试元组的类别
*
* @param list 训练数据集
* @param test 测试元组
* @param k 设定的K值
* @return 测试元组的类别
*/
public String knn(List<List<Double>> list, List<Double> test, int k) {
PriorityQueue<KNNNode> pq = new PriorityQueue<KNNNode>(k, comparator);
for (int i = 0; i < k; i++) {
List<Double> trainTuple = list.get(i);
Double c = trainTuple.get(0);
KNNNode node = new KNNNode(i, getDistance(test, trainTuple), c);
pq.add(node);
}
for (int i = 0; i < list.size(); i++) {
List<Double> t = list.get(i);
double distance = getDistance(test, t);
KNNNode top = pq.peek();
if (top.getDistance() > distance) {
pq.remove();
pq.add(new KNNNode(i, distance, t.get(0)));
}
}
return getMostClass(pq);
}
