Do I need to install Jupyter notebook in every virtual environment?

Question

I isolate my data science projects into virtual environments using pipenv. However, running a Jupyter notebok does not access the local environment and uses the default IPyKernel. I've seen that you can register virtual environments from within the environment, but this requires installing the ipykernel package which itself requires Jupyter!

Is there anyway to avoid this and just use a single Jupyter install for all virtual environments?

Answer 1

I found that there are few problems when reinstall jupyter for each environment separately: i.e. pip install jupyter jupyterlab in new environments.

I had multiple issues (with and without Conda), where Jupyter would install packages to a different python environment when you use !pip install a_package_name within a cell. The shell environment still kept track of the non-environment python, and you can tell this by comparing the outputs of !which python and

import sys
sys.executable

Therefore, when you tried to import the package, it would not be available, because the cells used the environment python/ kernel (as it detected the venv directory).

Answer 2

Generally, you'd install jupyter once and do the following in your virtual environments:

pip install ipykernel  
python -m ipykernel install --user

This isn't enough when you're running multiple Python versions.
There's a guide here that tries to address this:
https://medium.com/@henriquebastos/the-definitive-guide-to-setup-my-python-workspace-628d68552e14

It's not 100% failsafe, but it can help you avoid reinstalling jupyter notebook all the time.