cython-lib-template

A small template that wrap C code into python using cython, and integrate the extensions into an installable module. Developed around python 3.x.

A cython pyx file is included that implements a few C functions which can accept and return standard python data types and numpy ndarrays. These are compiled, wrapped, and integrated into the module using a standard setup.py script.

In addition to concrete examples of cython syntax, this repo also illustrates a working project structure with a working setup.py configuration (using setuptools) for Python projects with C extension modules, along with basic unit tests (together with a working Travis-CI config).

Build the lib

First, install cython (using pip or from a package manager) if you don't already have them. pip install cython

Then just run python setup.py develop to build the project in-place.

The module (with its wrapped C functions c_hello) will then be importable in python:

>>> from cython_lib import c_hello, factorial

Wrapped example functions

2 examples functions are defined in wrapped.pyx:

• A direct wrapping of a simple C "hello world" function, implemented in cfunc.c
• A C function to compute the factorial of a python integer, built using Cython syntax.

Benchmarks

For a quick benchmark of the two ndarray functions listed, run python3 test_lib.py.

$ python3 test_lib.py
[+] cython finished : 0.0001804828643798828 s
[+] python finished : 2.987328052520752 s