diff --git a/function.py b/function.py index f2e302f..81ca379 100644 --- a/function.py +++ b/function.py @@ -72,19 +72,15 @@ def train_logreg(X, y, learning_rate=0.01, iterations=1000): # 初始化权重 weights = np.zeros(X.shape[1]) - # 定义损失函数 - def loss(w): - predictions = sigmoid(np.dot(X, w)) - return -np.mean(y * np.log(predictions) + (1 - y) * np.log(1 - predictions)) + for _ in range(iterations): + # 计算预测值 + predictions = sigmoid(np.dot(X, weights)) + # 计算梯度 + gradient = np.dot(X.T, (predictions - y)) / len(y) + # 更新权重 + weights -= learning_rate * gradient - # 定义梯度函数 - def gradient(w): - predictions = sigmoid(np.dot(X, w)) - return np.dot(X.T, (predictions - y)) / len(y) - - # 使用minimize函数优化 - result = minimize(loss, weights, method='BFGS', jac=gradient) - return result.x + return weights def predict_logreg(inX, weights): """ @@ -113,4 +109,4 @@ if __name__ == "__main__": # 测试单个数据 y_pred = predict_logreg(X_test[11], weights) - print(f"预测结果: {y_pred}, 实际结果: {int(y_test[11])}") # 确保y_test[11]是整数 + print(f"预测结果: {y_pred}, 实际结果: {int(y_test[11])}") \ No newline at end of file