Virtualenv allows you to isolate a python environment for your python project 1. This is useful in when several of your projects depend on different versions of the same library, which triggers a problem if you have a system/user wide installation of the particular library. Thus, by isolating the python environment you can install the required version of the library without worrying about whether or not you will break another project.

How to…

You can install virtualenv using pip by [sudo] pip install virtualenv.

Then, for the basic usage you’ll need to do two steps

  1. $ virtualenv ENV_PATH, where ENV_PATH is a directory where the new virtual environment will be placed. The new environment will have pip and setuptools installed.
  2. You will need to source your new environment by $ source ENV_PATH/bin/activate

Example:

$ virtualenv venv
$ source venv/bin/activate

tested with

  • OS X 10.11.1
  • Python 2.7.10
  • pip 7.1.2
  • virtualenv 13.1.2

References

  1. Virtualenv docs ↩