Knn算法解决海伦约会问题代码python及其环境要求

以下是使用Python实现的KNN算法解决海伦约会问题的示例代码：

import numpy as np
import operator

def create_dataset():
    # 海伦约会数据集
    group = np.array([[1.0, 1.1], [1.0, 1.0], [0, 0], [0, 0.1]])
    labels = ['A', 'A', 'B', 'B']
    return group, labels

def classify0(inX, dataset, labels, k):
    # KNN分类算法
    dataset_size = dataset.shape[0]
    diff_mat = np.tile(inX, (dataset_size, 1)) - dataset
    sq_diff_mat = diff_mat ** 2
    sq_distances = sq_diff_mat.sum(axis=1)
    distances = sq_distances ** 0.5
    sorted_dist_indices = distances.argsort()
    class_count = {}
    for i in range(k):
        vote_label = labels[sorted_dist_indices[i]]
        class_count[vote_label] = class_count.get(vote_label, 0) + 1
    sorted_class_count = sorted(class_count.items(),
                                key=operator.itemgetter(1), reverse=True)
    return sorted_class_count[0][0]

if __name__ == '__main__':
    group, labels = create_dataset()
    result = classify0([0, 0], group, labels, 3)
    print(result)

该代码可以在Python 2.x或Python 3.x环境中运行，只需要安装NumPy库即可。可以使用以下命令安装NumPy库：

pip install numpy