python development environment on a mac

[Kendall Shaw]

On 03/13/2017 06:28 AM, macports at parvis.nl wrote:

> my son needs for his music studies a python development environment 2.7.13 plus the actual 3.x.
> his imac is on osx 10.11 el capitan.
>
...
> the big question: please explain to me the relation between macports python/ipython/pip/virtualenv and how i should use it? when & how macports, when & how not, why???

I can offer some information that isn't macports specific.

In some unspecified OS packaging system that includes python and python 
packages within it's own package management system, without using 
packages installed using the python package management system, you would 
be installing packages  system wide which would have updates available 
when updates were available in the OS package management system, with 
the cascading dependencies associated with that.

In that scenario, your python project would work for you because of the 
state of your OS. If you then shared the source with someone else they 
would have to try to make their system match your OS environment 
sufficiently to have the same python modules available.

pip is  a tool for interacting with a python package management system:

https://packaging.python.org/

Python packages, generally, will make available python modules which a 
python project will import.

When it is used as part of a software project it implies that you would 
organize your python software package in a way that it is compatible 
with a standard which makes it easy for people to know how to configure 
and build your project and to incorporate it into their projects.

virtualenv allows you to isolate your projects from each other and from 
a surrounding python system. So, for example, 1 project that has a 
dependency  that is incompatible with a dependency in another project 
can still work since they are isolated from each other.

Kendall