Search icon CANCEL
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Conferences
Free Learning
Arrow right icon
Arrow up icon
GO TO TOP
Learning Jupyter 5

You're reading from   Learning Jupyter 5 Explore interactive computing using Python, Java, JavaScript, R, Julia, and JupyterLab

Arrow left icon
Product type Paperback
Published in Aug 2018
Publisher
ISBN-13 9781789137408
Length 282 pages
Edition 2nd Edition
Languages
Tools
Arrow right icon
Author (1):
Arrow left icon
Dan Toomey Dan Toomey
Author Profile Icon Dan Toomey
Dan Toomey
Arrow right icon
View More author details
Toc

Table of Contents (14) Chapters Close

Preface 1. Introduction to Jupyter FREE CHAPTER 2. Jupyter Python Scripting 3. Jupyter R Scripting 4. Jupyter Julia Scripting 5. Jupyter Java Coding 6. Jupyter JavaScript Coding 7. Jupyter Scala 8. Jupyter and Big Data 9. Interactive Widgets 10. Sharing and Converting Jupyter Notebooks 11. Multiuser Jupyter Notebooks 12. What's Next? 13. Other Books You May Enjoy

Scala higher-order functions


A higher-order function either takes other functions as arguments or returns a function as its result.

We can use this example script:

def squared(x: Int): Int = x * x
def cubed(x: Int): Int = x * x * x

def process(a: Int, processor: Int => Int): Int = {processor(a) }

val fiveSquared = process(5, squared)
val sevenCubed = process(7, cubed)

We define two functions: one squares the number passed, and the other cubes the number passed.

Next, we define a higher-order function that takes a number to work on and a processor to apply.

Lastly, we call each function. For example, we call process() with 5 and the squared function. The process() function passes 5 to the squared() function and returns the result:

We take advantage of Scala's engine automatically printing out variable values to see the  expected result.

These functions are not doing very much. When I ran them, it took a few seconds for the results to display. I think there is a big performance hit using higher...

lock icon The rest of the chapter is locked
Register for a free Packt account to unlock a world of extra content!
A free Packt account unlocks extra newsletters, articles, discounted offers, and much more. Start advancing your knowledge today.
Unlock this book and the full library FREE for 7 days
Get unlimited access to 7000+ expert-authored eBooks and videos courses covering every tech area you can think of
Renews at $19.99/month. Cancel anytime