sklearn警告--DeprecationWarning

版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/qq_22073849/article/details/80830880

from sklearn.cross_validation import train_test_split

/Users/zjx/anaconda3/lib/python3.6/site-packages/sklearn/cross_validation.py:41: DeprecationWarning: This module was deprecated in version 0.18 in favor of the model_selection module into which all the refactored classes and functions are moved. Also note that the interface of the new CV iterators are different from that of this module. This module will be removed in 0.20.
“This module will be removed in 0.20.”, DeprecationWarning)

翻译：该模块在0.18版本中被弃用，支持所有重构的类和函数都被移动到的model_selection模块。 另请注意，新的CV迭代器的接口与本模块的接口不同。 此模块将在0.20中删除。

解决办法：将“from sklearn.cross_validation import train_test_split” 改为“from sklearn.model_selection import train_test_split”

>>> import numpy as np
>>> from sklearn.model_selection import train_test_split
>>> X, y = np.arange(10).reshape((5, 2)), range(5)
>>> X
array([[0, 1],
       [2, 3],
       [4, 5],
       [6, 7],
       [8, 9]])
>>> list(y)
[0, 1, 2, 3, 4]

>>> X_train, X_test, y_train, y_test = train_test_split(
...     X, y, test_size=0.33, random_state=42)
...
>>> X_train
array([[4, 5],
       [0, 1],
       [6, 7]])
>>> y_train
[2, 0, 3]
>>> X_test
array([[2, 3],
       [8, 9]])
>>> y_test
[1, 4]

>>> train_test_split(y, shuffle=False)
[[0, 1, 2], [3, 4]]

Parameters:

*arrays : sequence of indexables with same length / shape[0] Allowed inputs are lists, numpy arrays, scipy-sparse matrices or pandas dataframes. test_size : float, int, None, optional If float, should be between 0.0 and 1.0 and represent the proportion of the dataset to include in the test split. If int, represents the absolute number of test samples. If None, the value is set to the complement of the train size. By default, the value is set to 0.25. The default will change in version 0.21. It will remain 0.25 only if train_size is unspecified, otherwise it will complement the specified train_size. train_size : float, int, or None, default None If float, should be between 0.0 and 1.0 and represent the proportion of the dataset to include in the train split. If int, represents the absolute number of train samples. If None, the value is automatically set to the complement of the test size. random_state : int, RandomState instance or None, optional (default=None) If int, random_state is the seed used by the random number generator; If RandomState instance, random_state is the random number generator; If None, the random number generator is the RandomState instance used by np.random. shuffle : boolean, optional (default=True) Whether or not to shuffle the data before splitting. If shuffle=False then stratify must be None. stratify : array-like or None (default is None) If not None, data is split in a stratified fashion, using this as the class labels.

Returns:

splitting : list, length=2 * len(arrays) List containing train-test split of inputs. New in version 0.16: If the input is sparse, the output will be a scipy.sparse.csr_matrix. Else, output type is the same as the input type.

参考文章：
http://scikit-learn.org/stable/modules/generated/sklearn.model_selection.train_test_split.html