安装不同版本的 Python

Question

this might be a very simple question but I need your help. I work in a network and I cannot install the programs I want. Anyway, I need to use another version of python, which is installed in the directory /new_version/. Now, when I type "python" in a shell (I use bash) the command point to the version of python installed in the machine I'm working with. I'd love that when I type "python" this command point to the /new_version/ which I've installed. It would be also better if I can call this "new version" with another command, ie python2.

I tried changing the PYTHONPATH in the.bashrc but it didn't work.

Answer 1

Add the line

export PATH=/new_version/:$PATH

to your ~/.bashrc (or ~/.bash_profile ) file. Then, whenever you run python , it will find the new version first in your PATH . Note this is PATH , not PYTHONPATH . See the comment by @Aaron.

Edit: Only do it this way if you want python to point to the new version. Use an alias as @cularis suggested if you want to call it something different, or make a symlink with:

ln -s /new_version/python /path/to/a/dir/you/add/to/your/path/newpython

Answer 2

alias newpython="/path/to/your/new_version/python"

Add this to your .bashrc , you can then start the new python with newpython and the standard one with python .

Answer 3

Install virtualenv . With this you can easily set up different Python versions like that:

virtualenv -p /new_version/bin/python

Also, virtualenv enables you to easily install other Python packages via pip install .

And finally, there's a package called tox which can automate testing with different Python versions...