14
votes

I am trying to use Numpy in a Python 2.7.8 script in Windows. So, I download and installed the latest version of Anaconda (I also want to use some of the other tools in Anaconda) to the directory "C:/Anaconda". As default, I checked the boxing asking me if I wanted to add the path to the binary files to the Windows PATH.

After checking PATH, it contains the following: "C:\Anaconda;C:\Anaconda\Scripts".

Then, after installation I open a new Command Prompt, and in the Python envirnoment, I enter "import numpy", but this gives the error: "ImportError: No module named numpy".

What stage have I missed out in the installation process?

***** EDIT *****

I have just noticed that there is no file called "numpy" in either "C:\Anaconda" or "C:\Anaconda\Scripts". But according to the Anaconda website (http://docs.continuum.io/anaconda/pkg-docs.html), the installation should come with Numpy...

***** EDIT *****

It seems that Windows was running Python from an existing version of Python I had installed, which was not associated with NumPy. After deleting this, and running Python from the Anaconda installation, NumPy is now being recognised.

5
Is your Command Prompt a new one, opened after installing Anaconda? - Warren Weckesser
Yes -- a new Command Prompt instance after installation is complete. - Karnivaurus

5 Answers

24
votes

I had the same problem, getting the message "ImportError: No module named numpy".

I'm also using anaconda and found out that I needed to add numpy to the ENV I was using. You can check the packages you have in your environment with the command:

conda list

So, when I used that command, numpy was not displayed. If that is your case, you just have to add it, with the command:

conda install numpy

After I did that, the error with the import numpy was gone

5
votes

Yep you should start anaconda's python in order to use python libs which come with anaconda. Or otherwise you have to manually add anaconda\lib to pythonpath which is less trivial. You can start anaconda's python by a full path:

path\to\anaconda\python.exe

or you can run the following two commands as an admin in cmd to make windows pipe every .py file to anaconda's python:

assoc .py=Python.File
ftype Python.File=C:\path\to\Anaconda\python.exe "%1" %*

after this you'll be able just to call python scripts without specifying the python executable at all.

1
votes

Anaconda folder basically resides in C:\Users\\Anaconda. Try setting the PATH to this folder.

1
votes

Move path\to\anaconda in the PATH above path\to\python

1
votes

The above answers seem to resolve the issue. If it doesn't, then you may also try to update conda using the following command.

conda update conda

And then try to install numpy using

conda install numpy