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