逻辑回归模型python代码

逻辑回归是一种常用的分类算法，在Python中可以使用原生Python来实现逻辑回归模型。以下是一个简单的逻辑回归模型的Python代码示例：

import numpy as np

def sigmoid(z):
    return 1 / (1 + np.exp(-z))

def logistic_regression(X, y, num_iterations, learning_rate):
    m, n = X.shape
    theta = np.zeros((n, 1))
    
    for i in range(num_iterations):
        z = np.dot(X, theta)
        h = sigmoid(z)
        
        gradient = np.dot(X.T, (h - y)) / m
        theta -= learning_rate * gradient
        
    return theta

# 使用示例
X = np.array([[1, 2], [3, 4], [5, 6]])
y = np.array([[0], [1], [0]])

num_iterations = 1000
learning_rate = 0.01

theta = logistic_regression(X, y, num_iterations, learning_rate)

print("逻辑回归模型的参数(theta)：")
print(theta)