How to Solve ModuleNotFoundError: No module named ‘sklearn.cross_validation’

In Python, libraries can have updates that result in changes to the names of modules, classes, and functions. If you are using Scikit-Learn and attempt to import the cross-validation module you will raise the error: ModuleNotFoundError: No module named ‘sklearn.cross_validation’.

This tutorial will go through how to solve this problem with the help of a code example.

ModuleNotFoundError: No module named ‘sklearn.cross_validation’

Solution

You may get this error when trying to access a method from the cross-validation module, for example:

from sklearn.cross_validation import train_test_split

Which will raise the error:

---------------------------------------------------------------------------
ModuleNotFoundError                       Traceback (most recent call last)
1 from sklearn.cross_validation import train_test_split

ModuleNotFoundError: No module named 'sklearn.cross_validation'

All of the methods previously under cross-validation are now under model_selection. Therefore, you need to import train_test_split from sklearn.model_selection. Let’s look at the revised code:

from sklearn.model_selection import train_test_split

This import statement will not raise the modulenotfounderror and you can use the train_test_split helper function.

If you are not able to import the Scikit-Learn library at all, go to the following article to solve this problem: How to Solve Python ModuleNotFoundError: no module named ‘sklearn’.

Summary

Congratulations on reading to the end of this tutorial! The error ModuleNotFoundError: No module named ‘sklearn.cross_validation’ occurs when you try to import functions or classes from the cross_validation module instead of model_selection module. The cross_validation module no longer exists in Scikit-Learn.

For similar problems, you can search for the function or class you want to use in the Scikit-Learn API Reference. You will be able to find which module the class or function you want belongs to.

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Have fun and happy researching!