generated from LufsX/Challenge-kNN
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# function.py
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# function.py
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import numpy as np
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import numpy as np
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from scipy.spatial.distance import mahalanobis
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"""
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"""
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挑战说明:
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挑战说明:
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- 自行编写实现 KNN 分类算法。
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- 自行编写实现 KNN 分类算法。
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@@ -40,7 +40,7 @@ name = "尹家立"
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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=0):
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def classify0(inX, dataSet, labels, k=3):
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"""
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"""
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KNN 分类算法。
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KNN 分类算法。
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@@ -58,9 +58,9 @@ def classify0(inX, dataSet, labels, k=0):
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invCovMat = np.linalg.inv(covMat) # 计算协方差矩阵的逆
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invCovMat = np.linalg.inv(covMat) # 计算协方差矩阵的逆
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# Step 2: 计算马氏距离
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# Step 2: 计算马氏距离
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diffMat = dataSet - inX # 计算差值矩阵
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mahalanobisDist = np.array([
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left = np.dot(diffMat, invCovMat) # 左乘协方差矩阵的逆
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mahalanobis(inX, dataSet[i], invCovMat) for i in range(dataSet.shape[0])
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mahalanobisDist = np.sqrt(np.sum(left * diffMat, axis=1)) # 计算马氏距离
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]) # 使用 scipy 的 mahalanobis 函数计算马氏距离
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# Step 3: 按距离排序,得到索引
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# Step 3: 按距离排序,得到索引
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sortedDistIndices = mahalanobisDist.argsort()
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sortedDistIndices = mahalanobisDist.argsort()
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