diff --git a/function.py b/function.py index a7eb05f..7f86f51 100644 --- a/function.py +++ b/function.py @@ -7,9 +7,12 @@ name = "张钦诚" def classify0(inX, dataSet, labels, k=5): inX = np.array(inX) + # 计算欧氏距离的平方,避免开平方以提高效率 distances = np.sum((dataSet - inX) ** 2, axis=1) + # 获取距离最小的k个样本的索引 nearest_indices = np.argpartition(distances, k)[:k] nearest_labels = labels[nearest_indices] + # 统计k个最近邻中出现次数最多的标签 label_count = Counter(nearest_labels) return label_count.most_common(1)[0][0] @@ -20,8 +23,12 @@ def load_data(file_path): return features, labels def standardize(train_data, test_data): + """ + 对训练数据和测试数据进行标准化处理。 + """ mean = np.mean(train_data, axis=0) std = np.std(train_data, axis=0) + # 防止标准差为零 std[std == 0] = 1 train_standardized = (train_data - mean) / std test_standardized = (test_data - mean) / std @@ -31,17 +38,24 @@ if __name__ == "__main__": train_file = "datingTrainSet2.tsv" test_file = "datingTestSet2.tsv" + # 加载训练数据 train_data, train_labels = load_data(train_file) + # 加载测试数据 test_data, test_labels = load_data(test_file) + # 数据标准化 train_data, test_data = standardize(train_data, test_data) + # 测试样本 test_sample = [65915, 3.868359, 0.128078] + # 标准化测试样本 test_sample = (np.array(test_sample) - np.mean(train_data, axis=0)) / np.std(train_data, axis=0) + # 预测标签 predicted_label = classify0(test_sample, train_data, train_labels) print(f"预测的分类标签: {predicted_label}") + # 计算准确率 predictions = np.array([classify0(sample, train_data, train_labels) for sample in test_data]) accuracy = np.mean(predictions == test_labels) * 100 print(f"准确率: {accuracy:.2f}%")