Unknown file type error with .pyx file

Question

I'm trying to build a Python package (pyregion) that contains a *.pyx file and error comes during the build process. Checking out the below output:

$ python setup.py build
running build
running build_py
creating build
creating build/lib.macosx-10.5-x86_64-2.7
....
running build_ext
building 'pyregion._region_filter' extension
C compiler: gcc -fno-strict-aliasing -fno-common -dynamic -arch x86_64 -DNDEBUG -g -O3 -arch x86_64

error: unknown file type '.pyx' (from 'src/_region_filter.pyx')

Any ideas on what the issue could be? Just to note, I'm using the Enthought build of Python (7.1) on OSX with the latest Xcode (4.1).

Cheers

Answer 1

The .pyx should should be compiled to C with Pyrex and then compiled to object code. Check if a src/_region_filter.c file is present in the distribution and hack the setup.py script to build that instead. (Also, consider filing a bug report, since this shouldn't be happening.)

Answer 2

Install pyrex first and it will work.

Do the following: sudo pip install pyrex

Answer 3

python3.6 -m pip install Cython

Installing Cython solves the problem for me!

Answer 4

The only solution to this problem for me, when attempting to install pyFFTW, was to first install Cython via pip. Also see https://github.com/pyFFTW/pyFFTW/issues/252 .