diff --git a/function.py b/function.py index 80ff2f8..5450c89 100644 --- a/function.py +++ b/function.py @@ -47,19 +47,13 @@ from collections import Counter def classify(input_vector, dataSet, labels, k=3): """使用 KNN 算法对输入样本进行分类。""" - # 计算协方差矩阵和其逆矩阵 - cov_matrix = np.cov(dataSet, rowvar=False) - inv_cov_matrix = np.linalg.inv(cov_matrix + 1e-5 * np.eye(cov_matrix.shape[0])) # 添加小常数以防止奇异矩阵 - - # 计算马氏距离 - diffs = input_vector - dataSet - distances = np.sqrt(np.einsum('ij,jk->i', diffs, np.dot(inv_cov_matrix, diffs.T))) - + distances = np.sum((input_vector - dataSet) ** 2, axis=1) sorted_indices = distances.argsort() + k_nearest_distances = distances[sorted_indices[:k]] k_nearest_labels = labels[sorted_indices[:k]] # 计算权重(距离的倒数),避免除以零 - weights = 1 / (distances[sorted_indices[:k]] + 1e-5) + weights = 1 / (k_nearest_distances + 1e-5) # 归一化权重 weights /= weights.sum()