Book Image

Getting Started with Python

By : Fabrizio Romano, Benjamin Baka, Dusty Phillips
Book Image

Getting Started with Python

By: Fabrizio Romano, Benjamin Baka, Dusty Phillips

Overview of this book

This Learning Path helps you get comfortable with the world of Python. It starts with a thorough and practical introduction to Python. You’ll quickly start writing programs, building websites, and working with data by harnessing Python's renowned data science libraries. With the power of linked lists, binary searches, and sorting algorithms, you'll easily create complex data structures, such as graphs, stacks, and queues. After understanding cooperative inheritance, you'll expertly raise, handle, and manipulate exceptions. You will effortlessly integrate the object-oriented and not-so-object-oriented aspects of Python, and create maintainable applications using higher level design patterns. Once you’ve covered core topics, you’ll understand the joy of unit testing and just how easy it is to create unit tests. By the end of this Learning Path, you will have built components that are easy to understand, debug, and can be used across different applications. This Learning Path includes content from the following Packt products: • Learn Python Programming - Second Edition by Fabrizio Romano • Python Data Structures and Algorithms by Benjamin Baka • Python 3 Object-Oriented Programming by Dusty Phillips
Table of Contents (31 chapters)
Title Page
Copyright and Credits
About Packt
Contributors
Preface
8
Stacks and Queues
10
Hashing and Symbol Tables
Index

Graphs


A graph is a set of vertices and edges that form connections between the vertices. In a more formal approach, a graph G is an ordered pair of a set V of vertices and a set E of edges given as G = (V, E) in formal mathematical notation.

An example of a graph is given here:

Let's now go through some definitions of a graph:

  • Node or vertex: A point, usually represented by a dot in a graph. The vertices or nodes are A, B, C, D, and E.
  • Edge: This is a connection between two vertices. The line connecting A and B is an example of an edge.
  • Loop: When an edge from a node is incident on itself, that edge forms a loop.
  • Degree of a vertex: This is the number of vertices that are incident on a given vertex. The degree of vertex B is 4.
  • Adjacency: This refers to the connection(s) between a node and its neighbor. The node C is adjacent to node A because there is an edge between them.
  • Path: A sequence of vertices where each adjacent pair is connected by an edge.