How to execute a python script in a different directory?

Question

Solved see my answer below for anyone who might find this helpful.

I have two scripts a.py and b.py. In my current directory "C:\Users\MyName\Desktop\MAIN", I run > python a.py.

The first script, a.py runs in my current directory, does something to a bunch of files and creates a new directory (testA) with the edited versions of those files which are simultaneously moved into that new directory. Then I need to run b.py for the files in testA.

As a beginner, I would just copy and paste my b.py script into testA and execute the command again "> python b.py", which runs some commands on those new files and creates another folder (testB) with those edited files.

I am trying to eliminate the hassle of waiting for a.py to finish, move into that new directory, paste b.py, and then run b.py. I am trying to write a bash script that executes these scripts while maintaining my hierarchy of directories.

#!/usr/bin/env bash
 python a.py && python b.py

Script a.py runs smoothly, but b.py does not execute at all. There are no error messages coming up about b.py failing, I just think it cannot execute because once a.py is done, b.py does not exist in that NEW directory. Is there a small script I can add within b.py that moves it into the new directory? I actually tried changing b.py directory paths as well but it did not work.

For example in b.py:

mydir = os.getcwd() # would be the same path as a.py
mydir_new = os.chdir(mydir+"\testA")

I changed mydirs to mydir_new in all instances within b.py, but that also made no difference...I also don't know how to move a script into a new directory within bash.

As a little flowchart of the folders:

MAIN # main folder with unedited files and both a.py and b.py scripts
|
| (execute a.py)
|
--------testA # first folder created with first edits of files
         |
         | (execute b.py)
         |
         --------------testB # final folder created with final edits of files

TLDR: How do I execute a.py and b.py from the main test folder (bash script style?), if b.py relies on files created and stored in testA. Normally I copy and paste b.py into testA, then run b.py - but now I have 200+ files so copying and pasting is a waste of time.

user_10353722 · Answer

In your batch file, you can set the %PYTHONPATH% variable to the folder with the Python module. This way, you don't have to change directories or use pushd to for network drives. I believe you can also do something like

set "PYTHONPATH=%PYTHONPATH%;c:	he path	o\my folder\which contains my module"

This will append the paths I believe (This will only work if you already have set %PYTHONPATH% in your environment variables).

If you haven't, you can also just do

set "PYTHONPATH=c:	he path	o\my folder\which contains my module"

Then, in the same batch file, you can do something like

python -m mymodule ...

How to execute a python script in a different directory?

5 Answers