cython

Compile a Cython file to C

$ cython [module.pyx]

$ cython -3 [module.pyx]

$ cython --cplus [module.pyx]

$ cython -a [module.pyx]

$ cython -o [output.c] [module.pyx]

$ cython --embed [module.pyx]

cython [options] sourcefile.pyx_

Cython is a programming language and compiler that translates Python-like code to C or C++. It enables writing C extensions for Python with Python syntax, providing significant performance improvements over pure Python.
The compiler takes .pyx files (Cython source) and produces C or C++ files that can be compiled into Python extension modules. Cython code can include both Python and C type declarations, enabling fine-grained optimization.
The annotation mode (-a) is particularly useful for optimization, generating an HTML report showing which lines generate Python API calls versus pure C code, with color-coding to highlight slow paths.

-o FILE

Specify output C/C++ file name.

Use Python 3 syntax and semantics.

Use Python 2 syntax and semantics.

Generate C++ code instead of C.

Generate annotated HTML showing Python/C interaction.

Generate a main() function to embed Python.

Add include directory.

Set working directory.

Emit source line directives.

Set compiler directive.

Generated C files must still be compiled with a C compiler. Build systems like setuptools typically handle this. Type annotations affect both performance and behavior. C exceptions handling differs from Python exceptions.

Cython evolved from Pyrex, created by Greg Ewing in 2002. The Cython fork began in 2007, adding features like typed memoryviews and parallel support. It's widely used for scientific computing and creating Python bindings for C libraries.

python(1), gcc(1), cythonize(1)