No module named 'arc.arc_c_extensions' about arc-alkali-rydberg-calculator HOT 2 CLOSED

Hi @jacobhines

Thank you for the issue, and for an effort to locate solution in previous issues.

I understand you want to develop new functions on top of the existing ARC code, and that's why you want to work directly with forked repository, and not a package from pip.

Explanation why you see this...

A part of ARC that does Numerov integration of wavefunctions is written as C extension. Packages published on PyPI (available via pip) are wheels, i.e. they contain compiled (pre-build) C code for multiple OS, architectures and Python versions. In that sense, Python 3.7 is supported. However, if you don't want to use wheel (as I understand above), you can build C extension yourself by running

python setup.py  build_ext --inplace

This is easy on Linux (you need GNU compiler and Python dev headers) and OSX (you need Python dev headers and code development tools from OSX), but on Windows can be bit tricky to set up environment. I see from directory path above that you are on Windows.

... and what is the shortest solution

I recommend just to get build C extension from PyPI package. You can copy that single file into your local repository directory, and everything should work. Steps are:

1. Find on package distribution files corresponding to your Python and OS and architecture. I think you need ARC_Alkali_Rydberg_Calculator-2.0.5-cp37-cp37m-win_amd64.whl that is Python 3.7, Windows, on 64bit architecture.
2. Unzip downloaded folder and you will find there in arc directory compiled file you need arc_c_extensions.cp37-win_amd64.pyd. Copy this file in your local folder of forked ARC repository (copy into the ...\ARC-Alkali-Rydberg-Calculator\arc directory) and you should be ready to go!

@jacobhines please let me know if this resolves the issue, or there are problems encountered (I don't have Windows at hand to test this now).

Good luck with development, and don't hesitate to contact me if you have any further questions.
Nikola

from arc-alkali-rydberg-calculator.

Solved. Thanks for quickly answering my rookie question.

Best,
Jacob

from arc-alkali-rydberg-calculator.