Python on a mac

Fourthing homebrew and virtualenv. Any other way is madness. I love each project having its own environment. Different versions of django, celery, numpy, scipy, etc. PIL vs pillow, etc. No need to worry "well, I have django 1.5 installed because of that project I took over last week, but now that I'm starting a new one, I want to start a new project, I want django 1.6. Though maybe I want to kick the tires on django 1.7 this weekend.1) Why homebrew over macports? I can't recall why I made that choice six months ago, but I've been satisfied with macports. What is the difference/advantage?I've found brew to be simpler/cleaner to deal with than macports. Macports has a much larger selection, but I haven't found myself wanting anything. (Chances are if I am, I'll go with @snickerdoodle's suggestion and use debian in virtualbox.2) I will often use python for various scripts which I want to use on the fly, i.e., things not associated with a particular "project". Is it necessary to be always working within a virtualenv? What is the default version when using virtualenv?No. You just won't have any packages. If you need django 1.6 for a project, say you're trying to create a blog, make a virtual environment called myblog, activate it (literally two commands that take less than 5 seconds to type and execute), install django 1.6. When your done, deactivate your virtenv. When you inherit a project later on that uses django 1.5, you create a virtenv for it, activate it and tell pip to install the contents of the requirements.txt file. No need to worry that you have django 1.6 installed.3) Does homebrew solve the problem that I had with macports? In order to install some other programs (e.g., inkscape), macports wants to install its own version of python (or python packages) to satisfy dependencies.brew's inkscape does not require or optionally recommend the brew python or python 3 packages, but I haven't used it. AFAIK, whether you use brew's python or OS X's python is up to you and how you configure your $PATH, as long as both meet whatever other requirements your software has. (I use brew's python)

The very best thing you can do is use http://virtualenv.readthedocs.org/en/latest/. It does exactly what it sounds like: creates a virtual environment in which you can install whatever packages you want using pip. It makes having multiple different versions of Python on a single machine trivial and painless. My personal workflow is to use http://brew.sh/ to install the Python interpreter, then install virtualenv (and http://virtualenvwrapper.readthedocs.org/en/latest/), then activate the new virtualenv and use pip to install everything else. (On preview: I see coget has made basically the same recommendations. Proof that the Zen of Python - 'There should be one-- and preferably only one --obvious way to do it.' - is right!)

Homebrew does make /usr/local/bin/ world-writeable, which is a bit of a security faux pas.

Interesting to see the rapid convergence on advice. For me: * I used to have Fink on my old machine; on this one I started with MacPorts and have been happy with it so far. But it appears that the cool kids have moved on to Homebrew... * I used to have terrible Python package issues until I realized that I could get the full Enthought Python Distribution (EPD, now https://www.enthought.com/products/canopy/), and that had everything that I had been having trouble with. For the few stray packages I use pip and it plays well enough with EPD. (My $PATH gets the EPD python before the system one.)

Brew, always. Never MacPorts. Homebrew has never led me astray. MacPorts has caused more than a couple of "Welp, I guess this is so fucked I'm going to need a system reinstall" for me and others I know. Someone will probably say that's my own fault somehow, and maybe it is, but whatever it is that I do that triggers that in Macports has never once caused a problem with Homebrew. Virtualenv is a must-have, regardless of who supplies your python install.

I use vagrant and virtualbox for doing dev work on my Mac.

I use the free version of Continuum Analytics' https://store.continuum.io/cshop/anaconda/ Python distribution. Their package manager can install binary distributions of libraries like numpy, which can be nice for quickly setting up a working environment on a new machine without waiting for things to compile.

Seconding http://brew.sh/ instead of macports, and the liberal use of virtualenv.

Thanks all for the converging advice on homebrew and virtualenv. I have a few related followups then, if y'all are available: 1) Why homebrew over macports? I can't recall why I made that choice six months ago, but I've been satisfied with macports. What is the difference/advantage? 2) I will often use python for various scripts which I want to use on the fly, i.e., things not associated with a particular "project". Is it necessary to be always working within a virtualenv? What is the default version when using virtualenv? 3) Does homebrew solve the problem that I had with macports? In order to install some other programs (e.g., inkscape), macports wants to install its own version of python (or python packages) to satisfy dependencies.