vectorized on Python 3.8

It looks like from shapely import vectorized fails on Python 3.8 when Shapely is installed via pip:

    from shapely import vectorized
>   from ._vectorized import (contains, touches)
E   ModuleNotFoundError: No module named 'shapely.vectorized._vectorized'

https://travis-ci.org/mikedh/trimesh/jobs/627984786#L1423-L1426 I saw some “in the wild” reports of this too, though not sure what Python they were on: https://github.com/mikedh/trimesh/issues/667

[mikedh]

Thanks for tracking this down! Yup looks like 1.7a2 does the trick.

Kinda weird that it was reproducible even when building from a clone of the repo, maybe it was missing the geos headers or something? Feel free to close, or we can wait for the release to close.

For other people who want the pre-release you can install it with: pip install shapely==1.7a2

[sgillies]

@mikedh thank you for being patient and persistent. I’ve found the problem.

The Shapely 1.6.4.post2 source distribution (sdist) is defective and does not include a _vectorized.c file.

$ tar tzvf ~/Downloads/Shapely-1.6.4.post2.tar.gz | grep "\.c$"
-rw-r--r--  0 sean   staff  558528 Jul 18  2018 Shapely-1.6.4.post2/shapely/speedups/_speedups.c

The shapely 1.7a2 sdist does.

$ tar tzvf ~/Downloads/Shapely-1.7a2.tar.gz | grep "\.c$"
-rw-r--r--  0 seang  staff  578825 Jun 21  2019 Shapely-1.7a2/shapely/speedups/_speedups.c
-rw-r--r--  0 seang  staff  897094 Aug 30  2016 Shapely-1.7a2/shapely/vectorized/_vectorized.c

Would you be willing to try the 1.7a2 pre-release? It’s in good shape, in my opinion. It has far fewer known bugs than 1.6.4.post2, and seems to be serving geopandas users quite well. If not, you might try python 3.7, we have binary wheels on PyPI for py37 and shapely 1.6.4.post2.