Install Python Jupyter lab

Purpose: Install Jupyter lab

phenomenon:

When I installed Jupyter lab with pip and ran jupyter lab at the command prompt, I got the following error!

command prompt

C:\Users\<username>>jupyter lab
'jupyter lab'Is an internal or external command,
It is not recognized as an operable program or batch file.

Cause

• The direct cause was that when I installed jupyterlab with pip, it was installed in association with an unintended version of Python. ⇒ Which is [pip install jupyter lab] or [python -m pip install jupyter lab]? problem

• As a side factor, different versions of Python and pip were saved here and there, and the PATH setting was dirty. ⇒ When I ran Python at the command prompt, I faced a problem where I didn't know which version of Python was run.

environment:

• windows10 64 bit
• Python38
• jupyter lab 2.2.6

Supplement:

• Until now, when I installed Python, I didn't version control it and saved it in an appropriate folder, so I couldn't figure out what was there.
• As a result, I fell into a situation where the PATH was dirty or PIPs were scattered around, which PIP was being executed (I do not know where to save the package installed by PIP).

Installation method:

As a solution to these causes, I installed jupyter lab according to the following procedure.

1) Delete the original Python environment

I referred to the following site and did the work. https://gammasoft.jp/support/uninstall-python-completely-on-windows/

The flow of this work and supplements for each work are described below.

1. Uninstall the software No supplement

2. Manually delete the remaining folders Note) If you have several different versions of Python saved here and there, search for the following keywords in File Explorer and manually delete the found folder (both parents and children!). Search word: python, pip

3. Delete environment variables I deleted the environment variables by referring to the following site. ★★ Caution ★★) After installing Python many times, the environment variable settings got dirty and I had a hard time cleaning. To make sure it is deleted, delete both the user environment variable and the system environment variable. Also, restart your PC to ensure that the settings are updated. To check the update of the setting variable, it is more reliable to enter PATH at the command prompt rather than looking at the system properties.

How to delete environment variables: ttps: //www.javadrive.jp/python/install/index3.html

2) Installation

1. After deleting the original environment, perform the following installation work.

• Python installation Install according to the following site. Python installation: https://www.javadrive.jp/python/install/index1.html At this time, by checking "Add To Python PATH", the environment variables will be set automatically. Also, it is personally recommended to save the Python installation destination in a shallow location.

• pip upgrade

• pip should be installed with Python when you install it.

• Save to the Scripts folder directly under the Python folder
• Upgrade with the following command on the command prompt

prompt

#Normal
pip install pip --upgrade

#If you have multiple pips and you don't know which pip is being called
python -m pip install --upgrade pip

#If you want to specify the location of the pip you want to execute
cd <Full path of pip destination folder> -> pip install pip -upgrade  

• The second command executes pip directly under python, which is in the path.
• The third command is the most reliable because it specifies the save destination of pip and executes it.

• jupyter lab installation It was executed with reference to the following site. If you followed the steps above, the installation was surprisingly easy.

Go to the explanation page of jupyter lab installation method https://qiita.com/kirikei/items/a1639954ce5ccaf7ac3c

3) Summary

• When I installed and ran Jupyter lab, I got an error that jupyter could not be found.
• When I started by deleting the past Python, I was sick of it.
• The cause was that there were multiple Python pips and I couldn't delete them properly.
• The PATH setting could not be updated successfully.
• When I ran pip with multiple pips, an unexpected pip was run.
• As a result, if you delete unnecessary files, set the PATH correctly, understand the save destination of the package installed by pip, and suppress these three points, you can install jupyter lab successfully.