The module has been successfully installed but then it's not found when imported? - Python

Question

I'm trying to use the graphviz Python module and I've run into this problem: I pip installed it in my command prompt, but it's not showing up in IPython. I have additionally a Python 3.5 (32-bit) interpreter where it IS showing up, but I'm trying to figure out how to have it installed so it works in IPython.

I've been recommended to include the sys.path for each of the interpreters.

Anyone have any ideas as to how I'd change it?

Answer 1

Try using virtual environments.

   $ virtualenv -p python3 `/path/to/venv/dir`
   $ . `/path/to/venv/dir/bin/activate`
   (venv) $ # indicates virtual env is configured
   (venv) $ which pip python3
   (venv) $ pip install whatever
   (venv) $ python3 script.py

Answer 2

Your system python is 3.5.2 While IPython appears to be using 3.6 based on the sys.path output.

Try pip3.6 install graphviz

Answer 3

It is quite common to have such cases when there are multiple installations of python.

From the snapshot, we can infer that python 3.5 is default for the system and python 3.6 is installed for the specific user (Oliver Jr).

Installing any module without setting path variable will result in installing the module in default python (python 3.5)

Inorder to use the module in python 3.6, set the path variable as

SET PATH=C:\Users\Oliver Jr\Anaconda>;%PATH%;

Check if default python version is changed to python 3.6 by using

python --version

Then install the module using

pip install graphviz

You can also install using C:\UsersOliver Jr\Anaconda\bin\pip install graphviz

Answer 4

Try to list out installed packages in your python:

$pip freeze

Usually it happened because of PYTHONPATH problem. Did you try to reinstall your iPython? Maybe it was installed using different version of python.

$pip uninstall ipython
$pip install ipython

I tried using Python 3.6.3, it works well. Or you can try;

$pip3.6 install graphviz

Answer 5

You have 2 Python installations - one ordinary, as downloadable from https://www.python.org, installed in C:\Python; and another one, the self-contained Anaconda installation C:\Users\Oliver Jr\Anaconda.

You have installed Graphviz in the former - the standard Python distribution that resides in C:\Python, but you've installed IPython in Anaconda!

Since I suspect that you'd much prefer Anaconda over the standard Python as it makes installing scientific and mathematical packages on Windows much easier, you'd probably want to install it in your Anaconda distribution:

conda install -c anaconda graphviz 

Answer 6

Can't test it now, but what if install graphviz from IPython with "!":

! pip install graphviz

And restart IPython.

Answer 7

Try this:

conda install -c conda-forge python-graphviz

Or this: Conda comes with its own pip. Do

conda install pip

Then find the pip executable and run that directly (i.e /path/to/anacondapip install graphviz)