You'll learn all about iterators and iterables, which you have already worked with when writing for loops. You'll learn some handy functions that will allow you to effectively work with iterators. And you’ll finish the chapter with a use case that is pertinent to the world of data science and dealing with large amounts of data—in this case, data from Twitter that you will load in chunks using iterators.

Introduction to iterators

Iterators vs. Iterables

Iterating over iterables (1)

Iterating over iterables (2)

Iterators as function arguments

Playing with iterators

Using enumerate

Using zip

Using * and zip to 'unzip'

Using iterators to load large files into memory

Processing large amounts of Twitter data

Extracting information for large amounts of Twitter data

Congratulations!

Using iterators in PythonLand

In this chapter, you'll build on your knowledge of iterators and be introduced to list comprehensions, which allow you to create complicated lists—and lists of lists—in one line of code! List comprehensions can dramatically simplify your code and make it more efficient, and will become a vital part of your Python toolbox. You'll then learn about generators, which are extremely helpful when working with large sequences of data that you may not want to store in memory, but instead generate on the fly.

List comprehensions

Write a basic list comprehension

List comprehension over iterables

Writing list comprehensions

Nested list comprehensions

Advanced comprehensions

Using conditionals in comprehensions (1)

Using conditionals in comprehensions (2)

Dict comprehensions

Introduction to generator expressions

List comprehensions vs. generators

Write your own generator expressions

Changing the output in generator expressions

Build a generator

Wrapping up comprehensions and generators.

List comprehensions for time-stamped data

Conditional list comprehensions for time-stamped data

List comprehensions and generators

This chapter will allow you to apply your newly acquired skills toward wrangling and extracting meaningful information from a real-world dataset—the World Bank's World Development Indicators. You'll have the chance to write your own functions and list comprehensions as you work with iterators and generators to solidify your Python chops.

Welcome to the case study!

Zipping dictionaries

Writing a function to help you

Using a list comprehension

Turning this all into a DataFrame

Using Python generators for streaming data

Processing data in chunks (1)

Writing a generator to load data in chunks (2)

Writing a generator to load data in chunks (3)

Using pandas' read_csv iterator for streaming data

Writing an iterator to load data in chunks (1)

Writing an iterator to load data in chunks (2)

Writing an iterator to load data in chunks (3)

Writing an iterator to load data in chunks (4)

Writing an iterator to load data in chunks (5)

Final thoughts

Bringing it all together!

Tweets

World Bank World Development Indicators

Course Glossary

In this Python Toolbox course, you'll continue to build more advanced Python skills. First, you'll learn about iterators, objects you have already encountered in the context of for loops. You'll then learn about list comprehensions, which are extremely handy tools for all data professionals and developers working in Python. You'll end the course by working through a case study in which you'll apply all the techniques you learned in both parts of this course.

The videos contain live transcripts you can reveal by clicking "Show transcript" at the bottom left of the videos.
The course glossary can be found on the right in the resources section.
To obtain CPE credits, you need to complete the course and reach a score of 70% on the qualified assessment. You can navigate to the assessment by clicking on the CPE credits callout on the right.

Introduction to Functions in Python

Continue to build your modern Data Science skills by learning about iterators and list comprehensions.

Python Data Science Toolbox (Part 2)

Python Toolbox

Associate Data Scientist  in Python

Associate Python Developer

Python Programming Fundamentals

Data Scientist at DataCamp

Reading files in chunks

Let's practice!

https://s3.amazonaws.com/assets.datacamp.com/production/course_1531/subtitles/course_1531_3b90266563777ac8b16a7268b402dcdb.vtt

Bringing it all together! - Using pandas' read_csv iterator for streaming data

Using pandas' read_csv iterator for streaming data

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