Smith - Cython: a guide for Python programmers

• While programming Python, you have thought, These nested for loops would run hundreds of times faster in C, but the hassle isnt worth it.
• You have considered using PyPy, Numba, or even Julia but want something more mature and with better support tools.
• You have ever wished Python supported optional static typing to speed up the numeric expression that takes up 40 percent of your runtime.
• You use NumPy, SciPy, Pandas, a scikit, or some other data-intensive package and want to go beyond the prepackaged algorithms without compromising performance.
• You have a tested and optimized C or C++ library that you want to wrap with Python without learning the arcana of yet another interfacing language.
• You have considered reprogramming that performance-critical part of your Python application as an extension module but were (rightly) put off by all the fussy details.

Cython is unique in that it exists between languages. It is a hybrid, achimera, a saber-toothed moose lion. Cython is mostly Python and comes froma Python frame of mind, so this book assumes an intermediate level of Pythonexperience. You should be comfortable with all built-in data types, functions,classes, Pythons object model, modules, packages, and the more common packagesin the standard library. Knowing a bitor willingness to learnabout howCPython works under the hood is helpful as well.

Intermediate experience with NumPy is assumed for later chapters.

Cython also speaks C, so at least a beginners level of knowledge of the C orC++ language is necessary. Familiarity with the built-in C numerictypes, pointers, C arrays, structs, unions, enums, and macros is useful.Cython takes a lot of the scariness and danger out of programming in C, but togo really far, the more C knowledge you have, the better. The C andC++ wrapping chapters assume an intermediate level of familiaritywith these languages and are self-contained.

If you are just starting out in Python, you will likely benefit fromprogramming a few stretch projects before diving in here.

If you have had no exposure to C or C++, then you will likely need tohave reference material handy to help you understand the C- and C++-specific parts. Going through a C or C++ tutorial and having somefamiliarity with compiled languages will serve you well.