Best way to put functions python

Question

I bring a few days working on python coming from Matlab and I have the next doubt:

I had a matlab program with a lot of functions defined at the end of my m-file. Matlab recognizes those functions even if I call them at the beginning and they are defined at the bottom of my code.

Now, with python, I don't know what is the best way to put the functions because python needs to know the definition of the functions before calling them. I don't want to create a new file for each function. I would like to put all functions together but I can't figure it out. I hope you can help me.

Thx,

Jmac · Accepted Answer · 2013-07-03T15:57:58.507

6

Another way you can have all the functions is to add a function that does everything you want it to do:

def main():
    #do stuff
    f()
    g()
    ...

And add this to the end of the file:

if __name__ == '__main__':
    main()

This will only execute if your file is the main file. If you import your file from another file, then it won't execute all the code in main().

edited Jul 03 '13 at 15:57

answered Jul 02 '13 at 21:10

Jmac

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I'd prefer this method, just because it doesn't needlessly create other files. You can always refactor functions out later if you need to share them between modules. – acjay Jul 02 '13 at 21:18
I like this way and it works nicely too. Thx. For me, now it's more like matlab style because I have the main code on top and the functions at the end of the file. – tete Jul 02 '13 at 22:48

score 2 · Answer 2 · answered Jul 02 '13 at 19:59

2

You can put all the functions in a functions.py and include it in every document

import functions

then you can call a function by adding the prefix functions.

answered Jul 02 '13 at 19:59

zurfyx

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Easier than expected! Exactly using: from functions import * Thx! – tete Jul 02 '13 at 20:11
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@tete you should shy away from using `from functions import *` as explained in http://stackoverflow.com/q/2386714/1980029. – robjohncox Jul 02 '13 at 20:55
1

@tete, if you don't want to call all functions (mentioned by @robjohncox), you can do a from `functions import function1`. That is recommended and it is used a lot. – zurfyx Jul 03 '13 at 07:41

score 2 · Answer 3 · answered Jul 02 '13 at 20:42

2

Actually python does not need you to declare functions in any particular order to have them called.

For example this works fine :

def a():
  return b()

def b():
  return 1

a()

answered Jul 02 '13 at 20:42

rotoglup

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That's true but I don't like to have the functions at the top of the code. Thx. – tete Jul 02 '13 at 20:59
It's also important to note that Python throws an exception if you have the call to `a()` above the definition of `b()`. – Cody Piersall Jul 02 '13 at 21:22

Best way to put functions python

3 Answers3