/usr/lib64/python2.7/site-packages/sklearn/utils/validation.py:395 DeprecationWarning

解决:  Passing 1d arrays as data is deprecated in 0.17 and will raise ValueError in 0.19. Reshape your data either using X.reshape(-1, 1) if your data has a single feature or X.reshape(1, -1) if it contains a single sample.

错误信息:C:\Python27\lib\site-packages\sklearn\utils\validation.py:395: DeprecationWarning: Passing 1d arrays as data is deprecated in 0.17 and will raise ValueError in 0.19. Reshape your data either using X.reshape(-1, 1) if your data has a single feature or X.reshape(1, -1) if it contains a single sample.  DeprecationWarning)例子如下：

假设匹萨的直径与价格的数据，这就构成了训练数据，如下表所示：

训练样本	直径（英寸）	价格（美元）
1	6	7
2	8	9
3	10	13
4	14	17.5
5	18	18

用scikit-learn来构建模型。from sklearn.linear_model import LinearRegression# 创建并拟合模型X = [[6], [8], [10], [14], [18]]y = [[7], [9], [13], [17.5], [18]]model = LinearRegression()model.fit(X, y)print('预测一张12英寸匹萨价格：$%.2f' % model.predict([12])[0])

运行结果如下：

/usr/lib64/python2.7/site-packages/sklearn/utils/validation.py:395: DeprecationWarning: Passing 1d arrays as data is deprecated in 0.17 and will raise ValueError in 0.19. Reshape your data either using X.reshape(-1, 1) if your data has a single feature or X.reshape(1, -1) if it contains a single sample.  DeprecationWarning)预测一张12英寸匹萨价格：$13.68

我们将最后一句print改成如下：

print('预测一张12英寸匹萨价格：$%.2f' % model.predict(numpy.array([12]).reshape(-1,1))[0])

运行结果就不再上述错误