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Introduction to Functions in Python

4.6+
175 reviews
Beginner

Learn the art of writing your own functions in Python, as well as key concepts like scoping and error handling.

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Course Description

It's time to push forward and develop your Python chops even further. Python has tons of fantastic functions and a module ecosystem. However, as a data professional or developer, you'll constantly need to write your own functions to solve problems that are dictated by your data. You will learn the art of function writing in this first course. You'll come out of this course being able to write your very own custom functions, complete with multiple parameters and multiple return values, along with default arguments and variable-length arguments. You'll gain insight into scoping in Python, be able to write lambda functions and handle errors in your function writing practice. You'll wrap up each chapter by using your new skills to write functions that analyze Twitter data.
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In the following Tracks

Certification Available

Associate Data Scientist in Python

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  1. 1

    Writing your own functions

    Free

    You'll learn how to write simple functions, as well as functions that accept multiple arguments and return multiple values. You'll also have the opportunity to apply these new skills to questions commonly encountered by data professionals and developers.

    Play Chapter Now
    User-defined functions
    50 xp
    Strings in Python
    50 xp
    Recapping built-in functions
    50 xp
    Write a simple function
    100 xp
    Single-parameter functions
    100 xp
    Functions that return single values
    100 xp
    Multiple parameters and return values
    50 xp
    Functions with multiple parameters
    100 xp
    A brief introduction to tuples
    100 xp
    Functions that return multiple values
    100 xp
    Bringing it all together
    50 xp
    Bringing it all together (1)
    100 xp
    Bringing it all together (2)
    100 xp
  2. 2

    Default arguments, variable-length arguments and scope

    You'll learn to write functions with default arguments so that the user doesn't always need to specify them, and variable-length arguments so they can pass an arbitrary number of arguments on to your functions. You'll also learn about the essential concept of scope.

    Play Chapter Now
    Scope and user-defined functions
    50 xp
    Pop quiz on understanding scope
    50 xp
    The keyword global
    100 xp
    Python's built-in scope
    50 xp
    Nested functions
    50 xp
    Nested Functions I
    100 xp
    Nested Functions II
    100 xp
    The keyword nonlocal and nested functions
    100 xp
    Default and flexible arguments
    50 xp
    Functions with one default argument
    100 xp
    Functions with multiple default arguments
    100 xp
    Functions with variable-length arguments (*args)
    100 xp
    Functions with variable-length keyword arguments (**kwargs)
    100 xp
    Bringing it all together
    50 xp
    Bringing it all together (1)
    100 xp
    Bringing it all together (2)
    100 xp
  3. 3

    Lambda functions and error-handling

    Learn about lambda functions, which allow you to write functions quickly and on the fly. You'll also practice handling errors in your functions, which is an essential skill. Then, apply your new skills to answer data science questions.

    Play Chapter Now
    Lambda functions
    50 xp
    Pop quiz on lambda functions
    50 xp
    Writing a lambda function you already know
    100 xp
    Map() and lambda functions
    100 xp
    Filter() and lambda functions
    100 xp
    Reduce() and lambda functions
    100 xp
    Introduction to error handling
    50 xp
    Pop quiz about errors
    50 xp
    Error handling with try-except
    100 xp
    Error handling by raising an error
    100 xp
    Bringing it all together
    50 xp
    Bringing it all together (1)
    100 xp
    Bringing it all together (2)
    100 xp
    Bringing it all together (3)
    100 xp
    Bringing it all together: testing your error handling skills
    50 xp
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Training 2 or more people?

Get your team access to the full DataCamp platform, including all the features.

In the following Tracks

Certification Available

Associate Data Scientist in Python

Go To Track

datasets

Tweets

collaborators

Collaborator's avatar
Francisco Castro

prerequisites

Intermediate Python
Hugo Bowne-Anderson HeadshotHugo Bowne-Anderson

Data Scientist

Hugo is a data scientist, educator, writer and podcaster formerly at DataCamp. His main interests are promoting data & AI literacy, helping to spread data skills through organizations and society and doing amateur stand up comedy in NYC. If you want to know what he likes to talk about, definitely check out DataFramed, the DataCamp podcast, which he hosted and produced.
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Don’t just take our word for it

*4.6
from 175 reviews
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  • Thuthukani N.
    5 days

    I would have liked more lambda examples. It is complex, but doable with examples.

  • Mihaela G.
    22 days

    Made the learning experience fun and insteresting. Clearly explained concepts, followed by practical examples to help reinforce them. All in all, a very good introductory course that motivates me to keep on learning.

  • Ranjith V.
    23 days

    One of the best learning materials to under the scope of functions. The mix of videos explaining the content and immediately followed by practical work is well built to facilitate the learning.

  • Douglas D.
    25 days

    Very clear. It should be easier to find reference material

  • Rafael A.
    about 1 month

    It was amazing!!! Simple, practice and very easy to understand. I think in all lessons should have flash cards, It would be easier to review the previous lessons.

"I would have liked more lambda examples. It is complex, but doable with examples."

Thuthukani N.

"Made the learning experience fun and insteresting. Clearly explained concepts, followed by practical examples to help reinforce them. All in all, a very good introductory course that motivates me to keep on learning."

Mihaela G.

"One of the best learning materials to under the scope of functions. The mix of videos explaining the content and immediately followed by practical work is well built to facilitate the learning."

Ranjith V.

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