Book Image

The Python Workshop

By : Olivier Pons, Andrew Bird, Dr. Lau Cher Han, Mario Corchero Jiménez, Graham Lee, Corey Wade
Book Image

The Python Workshop

By: Olivier Pons, Andrew Bird, Dr. Lau Cher Han, Mario Corchero Jiménez, Graham Lee, Corey Wade

Overview of this book

Have you always wanted to learn Python, but never quite known how to start? More applications than we realize are being developed using Python because it is easy to learn, read, and write. You can now start learning the language quickly and effectively with the help of this interactive tutorial. The Python Workshop starts by showing you how to correctly apply Python syntax to write simple programs, and how to use appropriate Python structures to store and retrieve data. You'll see how to handle files, deal with errors, and use classes and methods to write concise, reusable, and efficient code. As you advance, you'll understand how to use the standard library, debug code to troubleshoot problems, and write unit tests to validate application behavior. You'll gain insights into using the pandas and NumPy libraries for analyzing data, and the graphical libraries of Matplotlib and Seaborn to create impactful data visualizations. By focusing on entry-level data science, you'll build your practical Python skills in a way that mirrors real-world development. Finally, you'll discover the key steps in building and using simple machine learning algorithms. By the end of this Python book, you'll have the knowledge, skills and confidence to creatively tackle your own ambitious projects with Python.
Table of Contents (13 chapters)

Lambda Functions

Lambda functions are small, anonymous functions that can be defined in a simple one-line syntax:

lambda arguments : expression

For example, take the following function that returns the sum of two values:

def add_up(x, y):
    return x + y
print(add_up(2, 5))
7

This function can equivalently be written using the lambda function syntax, as follows:

add_up = lambda x, y: x + y
print(add_up(2, 5)) 

You should get the following output:

7

Note that the main restriction of a lambda function is that it can only contain a single expression. That is, you need to be able to write the expression to return the value in a single line of code. This makes lambda functions convenient only in situations where the function is sufficiently simple such that it can be expressed in a single statement.

Exercise 55: The First Item in a List

In this exercise, you will write a lambda function, first_item, to select the first item in a list containing...