How to change jupyter kernel from Python 2 to python 3?

Question

I have installed Jupiter notebook and I only have python 2 as a default kernel. I want to change it from python 2 to python 3. How could I do that?

score 14 · Accepted Answer · edited Apr 24 '20 at 20:35

14

https://conda.io/projects/conda/en/latest/user-guide/tasks/manage-python.html

Follow the link for managing python. If you use python 2, then install python 3 by using this command.

conda create -n py36 python=3.6 anaconda

After installing python 3, activate python 3 by using this command

activate py36

Then open jupyter notebook, you will find python on your kernel.

edited Apr 24 '20 at 20:35

JohnBucMoore

3
3

answered Mar 22 '18 at 14:14

Sadman Sobhan

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This doesn't work for me. I can activate my environment, then open python and it is 3.8 (as I want it to be), but when I open jupyter notebook, the only option for a new file is in Python 2. – mikey Apr 12 '20 at 17:11
1

same here. did you find a way to fix it? – Mohamed Sajjadh Sep 14 '20 at 13:28

score 9 · Answer 2 · answered Jan 17 '19 at 04:53

You can do this with the following steps:

conda create -n py36 'python=3.6' ipykernel #Replace 3.6 with desired version.
To activate installed jupyter kernal you need run, source activate py36
python -m ipykernel install --user
The interesting part: if you want to switch between kernels (py2-py3) in the same notebook, you need to run, conda install nb_conda

However, if at any point you realize that some of the modules are not available, for that you need to check Anaconda Python version.

python - version

if it is not python 3.x, you need to run

conda create -n py36 python=3.6 anaconda
source active py36

I hope it helps and enjoy switching python versions in the same notebook. You can try to print something in both python2 and python 3.

step 3 was sufficient for me. This is the good answer. – user3653831 Mar 17 '21 at 10:49 — user3653831, Mar 17 '21 at 10:49

score 0 · Answer 3 · answered Mar 22 '18 at 12:43

0

In case you installed the python/jupyter with anaconda, simply update the python from 2.* to 3.*

answered Mar 22 '18 at 12:43

xmindata

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I have tried all. I have downloaded python 3. Could you explain me the process if you don't mind. I had google it as well. – Satyam Singh Mar 22 '18 at 14:06
3

Please be sure to include more explanation in your answers so that they're useful to future readers. – EJoshuaS - Stand with Ukraine May 27 '19 at 16:55

score 0 · Answer 4 · edited Oct 05 '21 at 22:13

0

You can do this with the following steps:

Create new env by using python3.

virtualenv -p /usr/bin/python3.7 jupyter_environment
Activate env

source jupyter_environment/bin/activate
Start jupyter

jupyter notebook --allow-root

Then open Jupyter notebook, you will find python3 by default on your kernel.

edited Oct 05 '21 at 22:13

Fabio Mendes Soares

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answered Oct 05 '21 at 12:35

Pradeep

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score 0 · Answer 5 · answered May 11 '22 at 08:48

I have succeeded to add Python 3.9 to Jupyter as follows.

# cd /usr/share/jupyter/kernels
# ls
python3
# cp python3 python3.9
# cd python3.9

and changed python3 in the kernel.json file to python3.9:

# cat kernel.json 
{
 "argv": [
  "/usr/bin/python3.9",
  "-m",
  "ipykernel_launcher",
  "-f",
  "{connection_file}"
 ],
 "display_name": "Python 3.9",
 "language": "python"

After this, the kernel may be changed through Kernel->Change kernel in Jupyter.

Python 3.9 was installed separately, simply with package manager (zypper in my case).

I think, this should work with Python 2 as well.

How to change jupyter kernel from Python 2 to python 3?

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