Including external files in Python

Question

I am writing a Python script which runs some simulations, but it takes in a lot of input parameters (about 20). So I was thinking of including all the simulation parameters in an external file. What's the easiest way of doing this?

One answer I found was in Stack Overflow question How to import a module given the full path?, putting all the simulation parameters in a file parm.py and importing that module using the imp package.

This would allow the user who runs this script to supply any file as input. If I import a module that way:

parm = imp.load_source('parm', '/path/to/parm.py')

then all the parameters have to be referenced as

parm.p1, parm.p2

However, I would just like to refer to them as p1, p2, etc. in my script. Is there a way to do that?

Answer 1

Importing arbitrary code from an external file is a bad idea.

Please put your parameters in a configuration file and use Python's ConfigParser module to read it in.

For example:

==> multipliers.ini <==
[parameters]
p1=3
p2=4

==> multipliers.py <==
#!/usr/bin/env python

import ConfigParser

config = ConfigParser.SafeConfigParser()
config.read('multipliers.ini')


p1 = config.getint('parameters', 'p1')
p2 = config.getint('parameters', 'p2')

print p1 * p2

Answer 2

You can use execfile() for this, but you should consider another way altogether.