ImportError in importing from sklearn: cannot import name check_build

Usually when I get these kinds of errors, opening the __init__.py file and poking around helps. Go to the directory C:Python27libsite-packagessklearn and ensure that there’s a sub-directory called __check_build as a first step. On my machine (with a working sklearn installation, Mac OSX, Python 2.7.3) I have __init__.py, setup.py, their associated .pyc files, and a binary _check_build.so.

Poking around the __init__.py in that directory, the next step I’d take is to go to sklearn/__init__.py and comment out the import statement—the check_build stuff just checks that things were compiled correctly, it doesn’t appear to do anything but call a precompiled binary. This is, of course, at your own risk, and (to be sure) a work around. If your build failed you’ll likely soon run into other, bigger problems.

>>> from sklearn import preprocessing, metrics, cross_validation

Traceback (most recent call last):
  File "<pyshell#6>", line 1, in <module>
    from sklearn import preprocessing, metrics, cross_validation
  File "D:Python27libsite-packagessklearn__init__.py", line 31, in <module>
    from . import __check_build
ImportError: cannot import name __check_build
>>> ================================ RESTART ================================
>>> from sklearn import preprocessing, metrics, cross_validation
>>> 

So, simply try to restart the shell!

After installing numpy , scipy ,sklearn still has error

Solution:

Setting Up System Path Variable for Python & the PYTHONPATH Environment Variable

System Variables: add C:Python34 into path
User Variables: add new: (name)PYTHONPATH (value)C:Python34Libsite-packages;

I had the same issue on Windows. Solved it by installing Numpy+MKL from http://www.lfd.uci.edu/~gohlke/pythonlibs/#numpy (there it’s recommended to install numpy+mkl before other packages that depend on it) as suggested by this answer.

If you use Anaconda 2.7 64 bit, try

conda upgrade scikit-learn

and restart the python shell, that works for me.

Second edit when I faced the same problem and solved it:

conda upgrade scikit-learn

also works for me

None of the other answers worked for me. After some tinkering I unsinstalled sklearn:

pip uninstall sklearn

Then I removed sklearn folder from here: (adjust the path to your system and python version)

C:Users%USERNAME%AppDataRoamingPythonPython36site-packages

And the installed it from wheel from this site: link

The error was there probably because of a version conflict with sklearn installed somewhere else.

I had problems importing SKLEARN after installing a new 64bit version of Python 3.4 from python.org.

Turns out that it was the SCIPY module that was broken, and alos failed when I tried to “import scipy”.

Solution was to uninstall scipy and reinstall it with pip3:

C:> pip uninstall scipy

[lots of reporting messages deleted]

Proceed (y/n)? y
  Successfully uninstalled scipy-1.0.0

C:Users>pip3 install scipy

Collecting scipy
  Downloading scipy-1.0.0-cp36-none-win_amd64.whl (30.8MB)
    100% |████████████████████████████████| 30.8MB 33kB/s
Requirement already satisfied: numpy>=1.8.2 in c:usersjohnmccurdyappdataloca
lprogramspythonpython36libsite-packages (from scipy)
Installing collected packages: scipy
Successfully installed scipy-1.0.0

C:Users>python
Python 3.6.4 (v3.6.4:d48eceb, Dec 19 2017, 06:54:40) [MSC v.1900 64 bit (AMD64)]
 on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import scipy
>>>
>>> import sklearn
>>>

In windows:

I tried to delete sklearn from the shell: pip uninstall sklearn, and re install it but doesn’t work ..

the solution:

1- open the cmd shell.
2- cd c:pythonVERSIONscripts
3- pip uninstall sklearn
4- open in the explorer: C:pythonVERSIONLibsite-packages
5- look for the folders that contains sklearn and delete them ..
6- back to cmd: pip install sklearn

My solution for Python 3.6.5 64-bit Windows 10:

1. pip uninstall sklearn
2. pip uninstall scikit-learn
3. pip install sklearn

No need to restart command-line but you can do this if you want.
It took me one day to fix this bug. Hope this help.

i had the same problem reinstalling anaconda solved the issue for me

For me,
I was upgrading the existing code into new setup by installing Anaconda from fresh with latest python version(3.7)
For this,

from sklearn import cross_validation, 
from sklearn.grid_search import GridSearchCV

to

from sklearn.model_selection import GridSearchCV,cross_validate

no need to uninstall & then re-install sklearn

try this:

from sklearn.model_selection import train_test_split