Book Image

Python: Master the Art of Design Patterns

Book Image

Python: Master the Art of Design Patterns

Overview of this book

Python is an object-oriented scripting language that is used in everything from data science to web development. Known for its simplicity, Python increases productivity and minimizes development time. Through applying essential software engineering design patterns to Python, Python code becomes even more efficient and reusable from project to project. This learning path takes you through every traditional and advanced design pattern best applied to Python code, building your skills in writing exceptional Python. Divided into three distinct modules, you’ll go from foundational to advanced concepts by following a series of practical tutorials. Start with the bedrock of Python programming – the object-oriented paradigm. Rethink the way you work with Python as you work through the Python data structures and object-oriented techniques essential to modern Python programming. Build your confidence as you learn Python syntax, and how to use OOP principles with Python tools such as Django and Kivy. In the second module, run through the most common and most useful design patterns from a Python perspective. Progress through Singleton patterns, Factory patterns, Façade patterns and more all with detailed hands-on guidance. Enhance your professional abilities in in software architecture, design, and development. In the final module, run through the more complex and less common design patterns, discovering how to apply them to Python coding with the help of real-world examples. Get to grips with the best practices of writing Python, as well as creating systems architecture and troubleshooting issues. This Learning Path combines some of the best that Packt has to offer in one complete, curated package. It includes content from the following Packt products: ? Python 3 Object-Oriented Programming - Second Edition by Dusty Phillips ? Learning Python Design Patterns - Second Edition by Chetan Giridhar ? Mastering Python Design Patterns by Sakis Kasampalis
Table of Contents (6 chapters)
4
A. Bibliography
5
Index

Chapter 15. The Strategy Pattern

Most problems can be solved in more than one way. Take, for example, the sorting problem, which is related to putting the elements of a list in a specific order. There are many sorting algorithms, and, in general, none of them is considered the best for all cases [j.mp/algocomp]. There are different criteria that help us pick a sorting algorithm on a per-case basis. Some of the things that should be taken into account are:

  • Number of elements that need to be sorted: This is called the input size. Almost all the sorting algorithms behave fairly well when the input size is small, but only a few of them have good performance with a large input size.
  • Best/average/worst time complexity of the algorithm: Time complexity is (roughly) the amount of time the algorithm takes to complete, excluding coefficients and lower order terms. This is often the most usual criterion to pick an algorithm, although it is not always sufficient.
  • Space complexity of the algorithm...