4. Functions

Objectives

• Create custom functions.
• Import and use Python Standard Library modules, such as random and math, to reuse code and avoid “reinventing the wheel.”
• Pass data between functions.
• Generate a range of random numbers.

Objectives (cont.)

• Learn simulation techniques using random-number generation.
• Seed the random number generator to ensure reproducibility.
• Pack values into a tuple and unpack values from a tuple.
• Return multiple values from a function via a tuple.
• Understand how an identifier’s scope determines where in your program you can use it.

Objectives (cont.)

• Create functions with default parameter values.
• Call functions with keyword arguments.
• Create functions that can receive any number of arguments.
• Use methods of an object.

Outline

• 4.1 Introduction
• 4.2 Defining Functions
• 4.3 Functions with Multiple Parameters
• 4.4 Random-Number Generation
• 4.5 Case Study: A Game of Chance
• 4.6 Python Standard Library
• 4.7 math Module Functions
• 4.8 Using IPython Tab Completion for Discovery
• 4.9 Default Parameter Values
• 4.10 Keyword Arguments
• 4.11 Arbitrary Argument Lists
• 4.12 Methods: Functions That Belong to Objects
• 4.13 Scope Rules
• 4.14 import: A Deeper Look
• 4.15 Passing Arguments to Functions: A Deeper Look
• 4.16 Function-Call Stack
• 4.17 Functional-Style Programming
• 4.18 Intro to Data Science: Measures of Dispersion
• 4.19 Wrap-Up
• Exercises

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©1992–2020 by Pearson Education, Inc. All Rights Reserved. This content is based on Chapter 4 of the book Intro to Python for Computer Science and Data Science: Learning to Program with AI, Big Data and the Cloud.

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