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From: Rob Gaddi <rgaddi@technologyhighland.invalid>
Newsgroups: comp.lang.python
Subject: Re: initializing "parameters" class in Python only once?
Date: Mon, 14 Jul 2014 16:07:04 -0700
Organization: Highland Technology, Inc.
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On Mon, 14 Jul 2014 15:24:26 -0700
Catherine M Moroney <Catherine.M.Moroney@jpl.nasa.gov> wrote:

> Hello,
> 
> Pardon me for not using the proper Python language terms, but I hope 
> that people can still understand the question:
> 
> The problem:  I'm writing a large Python program and I have a bunch of
> parameters (whose values are static) that I want to make available to
> the rest of the code with minimum overhead and duplicate processing.
> 
> I think that the simplest way would be to create a file called 
> "Params.py" and then simply have statements like a = 1, b = 2, etc.
> in there (no classes, no methods, just a bunch of declarations).  But, 
> some of these static parameters have to be calculated rather than simply 
> hard-coded.
> 
> I thought of creating a class called Params and having a bunch of
> methods (decorated with @classmethod) that set/calculate the value of
> all the parameters.  Easy enough, but then I have to create a Params
> object in every source file that uses these parameters, and that seems
> wasteful.
> 
> The actual scope of the problem is very small, so memory/cpu time is not
> an issue.  I'm just looking for the most pythonic/elegant way of doing this.
> 
> What is the recommended way of passing a bunch of static (hard-coded and 
> calculated) parameters to various parts of the code?
> 
> Thank you for any advice,
> 
> Catherine

You're 90% of the way there.  You can just create params.py, fill it
with statements that are either hard-coded or calculated as necessary,
and import params from all over the rest of the program.  Once the
interpreter has imported it for the first time, everyone else just gets
a link to the same instance of the module rather than running it all
over and over again.

-- 
Rob Gaddi, Highland Technology -- www.highlandtechnology.com
Email address domain is currently out of order.  See above to fix.