virtual-environments.md

How to setup virtual environments for Python

This is a summary guide on how to setup virtual environments for Python using virtualenv and virtualenvwrapper. A couple of good references are:

• Hitchhiker's guide to Python
• virtualenvwrapper documentation

Installation

1. Make sure to have pip installed

sudo apt install python-pip

2. Install virtualenv

Note: if installed without sudo, pip will install under ~/.local/

sudo pip install virtualenv

3. Install virtualenvwrapper

Note: if installed without sudo, pip will install under ~/.local/

sudo pip install virtualenvwrapper

5. Add the following lines to ~/.bashrc

Note: you may change the directory of the virtual environments from ~/.virtualenvs to something else

export WORKON_HOME=$HOME/.virtualenvs
source /usr/local/bin/virtualenvwrapper.sh

5. Reload ~/.bashrc

source ~/.bashrc

Basic commands:

• mkvirtualenv name-of-virtualenv: make new virtual environment
• workon name-of-virtualenv: start session within virtual environment
• deactivate name-of-virtualenv: end session
• rm -r $WORKON_HOME/name-of-virtualenv: remove virtual environment

How to specify the Python version of a new virtual environment

See StackOverflow question

For example, to explicitly specify Python 3:

mkvirtualenv --python=`which python3` name-of-virtualenv