Notes for virtualenv

03 May 2016

• Python
• virtualenv

Notes for virtualenv

Virtualenv is a tool for creating isolated ‘virtual’ python environment. It makes sure different versions of packages and dependencies can exist in a same machine.

To install: pip install virtualenv

Basic command:

• virtualenv ENV: ENV is a directory to place the new virtual enviornment.
  • ENV/lib/ and ENV/include/ are created and used to store library files for a new virtualenv python.
  • ENV/bin is created for executables files. Runing a script with #! /path/to/ENV/bin/python would run that script under this virtualenv’s python.
• Enable a virtual environment: source ENV/bin/activate
• Disable a virtual environment: deactivate
• Delte a virtual environment: deactivate and rm -r ENV

• Make envrionment relocatable: virtualenv --relocatable ENV

• Check what is installed:
  • pip install yolk
  • yolk -l

Here is a great tutorial for virtualenv.

To use virtualenv install Python3, we can do the following (reference):

• pip install --upgrade virtualenv
• virtualenv -p python3 envname