创建具有多个级别的文件夹的python包

Question

I would like to create a package of my python code. My folder structure is like below:

sing*(this is a folder)*
--ml*(this is a folder)*
----regression*(this is a folder)*
------linear.py*(this is a class file with functions in it)* 
----classification*(this is a folder)*
------logistic.py*(this is a class file with functions in it)* 

i want to access class within linear.py by something like:

from sing.ml.regression import linear

Please advice how to create a package like this

thanks in advance

Answer 1

sing
    __init__.py
    -ml
        __init__.py
        -regression
           __init__.py
           linear.py

        -classification
           __init__.py
           logistic.py

And if the working directory of application is not parent folder of sing then you need to register folder 'sing' into PYTHONPATH environment variable.

For importing linear from sing folder you can use relative path:

from ml.regression import linear

and for calling function of linear file you can use:

linear.<*functionname*>(...)

Answer 2

You need to add a __init__.py files in every folder, so that python interpret the other *.py files (and folder) as packages. A empty file is enough.