What is Virtualenv?
A Virtual Environment, put simply, is an isolated working copy of Python which
allows you to work on a specific project without worry of affecting other projects
It enables multiple side-by-side installations of Python, one for each project.
It doesn’t actually install separate copies of Python, but it does provide a
clever way to keep different project environments isolated.
Verify if Virtualenv is installed
$ virtualenv --version
Install Virtualenv
$ sudo apt-get install python-virtualenv or $ sudo easy_install virtualenv or $ sudo pip install virtualenv
Setup and Use Virtualenv
First create a directory for your new shiny isolated environment
$ mkdir ~/virtualenvironment
To create a folder for your project that includes a clean copy of Python,
simply run:
$ virtualenv ~/virtualenvironment/myproject
or
$ virtualenv --system-site-packages ~/virtualenvironment/myproject
You can also use the Python interpreter of your choice (like python2.7).
$ virtualenv -p /usr/bin/python2.7 myproject
To begin working with your project, you have to cd into your directory (project) and activate the virtual environment.
$ cd ~/virtualenvironment/myproject/bin
$ source activate
Install a package in your Virtualenv
If you look at the bin directory in your virtualenv, you’ll see easy_install which has been modified to put eggs and packages in the virtualenv’s site-packages directory. To install an app in your Virtualenv:
$ sudo pip install --upgrade tensorflow
To exit your virtualenv just type “deactivate”.
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