Cython

Chapter 2. Compiling and Running Cython Code

I was taught that the way of progress was neither swift nor easy.

— M. Curie

It’s not that I’m so smart, it’s just that I stay with problems longer.

— A. Einstein

One of the more significant differences between Python and C or C++ is that Python is interpreted while C and C++ are compiled. When developing a Python program, we can immediately run code after making a modification, while C and C++ require an intervening compilation step. Compiling a large C or C++ code base can take hours or days. Using Python can allow much more rapid development, leading to a significant productivity boost.

Like C and C++, Cython requires a compilation step before the source can be run. This compilation step can be explicit or implicit. Both modes have their uses. One nice feature of automatically compiling Cython is that it makes working with Cython feel like working with pure Python. Whether compiling explicitly or implicitly, because Cython can be applied selectively to small sections of a Python code base, Cython’s compilation requirement can be minimized.

This chapter will cover the various ways to compile Cython code so that it can be run by Python. There are several options:

• Cython code can be compiled and run interactively from an IPython interpreter.
• It can be compiled automatically at import time.
• It can be separately compiled by build tools like Python’s distutils.
• It can be integrated into standard build systems such as make ...