diff --git a/function.py b/function.py index 5f6d6a6..34ff048 100644 --- a/function.py +++ b/function.py @@ -38,7 +38,7 @@ name = "吴俊煯" # 这里写自己的代码实现 -def classify0(inX, dataSet, labels,k=4): +def classify0(inX, dataSet, labels,k=3): """ KNN 分类算法。 @@ -50,26 +50,22 @@ def classify0(inX, dataSet, labels,k=4): Returns: - int: 预测的分类标签。 """ - # 确保 k 不大于数据集的大小 - k = min(k, dataSet.shape[0]) + # 计算每个训练样本与输入样本的欧氏距离 + distances = [euclidean_distance(inX, dataSet[i]) for i in range(len(dataSet))] - # 计算测试样本与每个训练样本之间的距离 - diffMat = np.tile(inX, (dataSet.shape[0], 1)) - dataSet - sqDiffMat = diffMat ** 2 - distances = np.sqrt(sqDiffMat.sum(axis=1)) + # 排序并获取索引 + sorted_distances_indices = np.argsort(distances) - # 对距离进行排序,并获取索引 - sortedDistIndicies = distances.argsort() + # 选择前 k 个距离最小的样本 + k_indices = sorted_distances_indices[:k] - # 选择距离最小的k个点 - classCount = {} - for i in range(k): - voteIlabel = labels[sortedDistIndicies[i]] - classCount[voteIlabel] = classCount.get(voteIlabel, 0) + 1 + # 提取这些样本的标签 + k_nearest_labels = [labels[i] for i in k_indices] - # 多数投票 - sortedClassCount = sorted(classCount.items(), key=lambda item: item[1], reverse=True) - return sortedClassCount[0][0] + # 对这些标签进行投票,返回出现次数最多的标签 + from collections import Counter + return Counter(k_nearest_labels).most_common(1)[0][0] + def load_data(file_path): """