generated from LufsX/Challenge-kNN
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@@ -41,13 +41,15 @@ name = "李燕如"
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# 这里写自己的代码实现
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# 这里写自己的代码实现
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def classify0(inX, dataSet, labels, k=5):
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import numpy as np
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def classify0(inX, dataSet, labels, k=3):
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# 数据标准化
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# 数据标准化
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dataSet = (dataSet - np.mean(dataSet, axis=0)) / np.std(dataSet, axis=0)
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dataSet = (dataSet - np.mean(dataSet, axis=0)) / np.std(dataSet, axis=0)
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inX = (inX - np.mean(dataSet, axis=0)) / np.std(dataSet, axis=0)
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inX = (inX - np.mean(dataSet, axis=0)) / np.std(dataSet, axis=0)
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# 计算距离
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# 计算距离
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distances = np.sqrt(np.sum((dataSet - inX) ** 2, axis=1))
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distances = [distance.euclidean(inX, x) for x in dataSet]
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# 获取k个最近邻的索引
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# 获取k个最近邻的索引
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k_indices = np.argsort(distances)[:k]
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k_indices = np.argsort(distances)[:k]
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@@ -55,14 +57,16 @@ def classify0(inX, dataSet, labels, k=5):
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# 获取这些样本对应的标签
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# 获取这些样本对应的标签
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k_nearest_labels = labels[k_indices]
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k_nearest_labels = labels[k_indices]
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# 权重分配(距离的倒数)
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# 投票决定分类
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weights = 1 / distances[k_indices]
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result = {}
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weights /= np.sum(weights) # 归一化权重
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for label in k_nearest_labels:
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if label in result:
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result[label] += 1
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else:
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result[label] = 1
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# 加权投票
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# 返回出现次数最多的类别
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prediction = np.argmax(np.bincount(k_nearest_labels, weights=weights))
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return max(result, key=result.get)
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return prediction
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def load_data(file_path):
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def load_data(file_path):
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data = np.loadtxt(file_path, delimiter="\t")
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data = np.loadtxt(file_path, delimiter="\t")
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