JavaScript for data science

245 Pages·2020·13.142 MB·English

by  Gans, Maya, Hodges, Toby, Wilson, Greg

JavaScript for Data Science
Chapman & Hall/CRC Data Science Series
About the Series
Reflecting the interdisciplinary nature of the field, this new book series brings together
researchers, practitioners, and instructors from statistics, computer science, machine learn-
ing, and analytics. The series will publish cutting-edge research, industry applications, and
textbooks in data science.
Features:
• Presents the latest research and applications in the field, including new statistical and com-
putational techniques
• Covers a broad range of interdisciplinary topics
• Provides guidance on the use of software for data science, including R, Python, and Julia
• Includes both introductory and advanced material for students and professionals
• Presents concepts while assuming minimal theoretical background
The scope of the series is broad, including titles in machine learning, pattern recognition,
predictive analytics, business analytics, visualization, programming, software, learning analyt-
ics, data collection and wrangling, interactive graphics, reproducible research, and more. The
inclusion of examples, applications, and code implementation is essential.
JavaScript for Data Science
Maya Gans, Toby Hodges, Greg Wilson
Basketball Data Science: With Applications in R
Paola Zuccolotto, Marica Manisera
Cybersecurity Analytics
Rakesh M. Verma, David J. Marchette
Introduction to Data Science: Data Analysis and Prediction Algorithms with R
Rafael A. Irizarry
Feature Engineering and Selection: A Practical Approach for Predictive Models
Max Kuhn, Kjell Johnson
Probability and Statistics for Data Science: Math + R + Data
Norman Matloff
JavaScript for Data Science
Maya Gans
Toby Hodges
Greg Wilson
CRC Press
Taylor & Francis Group
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International Standard Book Number-13: 978-0-367-42652-1 (Hardback)
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Dedication

For Jordan

who taught me failures pave the way to success.

— Maya

For Oskar.

— Toby
For Kara, Claudia, Erin, Gabriela, Hannah, Laura, and Julia.
— Greg
All royalties from the sale of this book are being donated to R-Ladies,

a worldwide organization whose mission is

to promote gender diversity in the R community.

Contents

Chapter 1 Introduction .....................................................................................1

1.1 WhoYouAre..........................................................................1

1.2 Who We Are ...........................................................................2

1.3 Setting Up...............................................................................3

1.4 Contributing............................................................................3

1.4.1 Acknowledgments......................................................4

1.5 Exercises.................................................................................4

Chapter 2 Basic Features..................................................................................5

2.1 Hello, World............................................................................5

2.2 Basic Data Types ....................................................................5

2.3 Control Flow...........................................................................7

2.4 Formatting Strings ..................................................................8

2.5 Objects....................................................................................8

2.6 Functions...............................................................................10

2.7 Modules ................................................................................12

2.8 Exercises...............................................................................13

Chapter 3 Callbacks .......................................................................................19

3.1 The Call Stack.......................................................................19

3.2 Functions of Functions .........................................................20

3.3 Anonymous Functions..........................................................24

3.4 Functional Programming......................................................25

3.5 Closures ................................................................................27

3.6 Exercises...............................................................................30

Chapter 4 Objectsand Classes.......................................................................33

4.1 Doing It By Hand..................................................................33

4.2 Classes ..................................................................................34

4.3 Inheritance ............................................................................36

4.4 Exercises...............................................................................38

Chapter 5 HTML and CSS.............................................................................43

5.1 Formatting.............................................................................43

5.2 Text .......................................................................................43

5.3 Pages.....................................................................................44

5.4 Attributes ..............................................................................45

vii
viii Contents
5.5 Lists.......................................................................................46

5.6 Tables....................................................................................47

5.7 Links.....................................................................................47

5.8 Images...................................................................................48

5.9 Cascading Style Sheets.........................................................49

5.10 Bootstrap...............................................................................51

5.11 Exercises...............................................................................53

Chapter 6 Manipulating Pages .......................................................................55

6.1 Counting Paragraphs.............................................................55

6.2 Creating a Table of Contents ................................................57

6.3 Sortable Lists........................................................................59

6.4 Bibliographic Citations.........................................................62

6.5 A Real-time Clock................................................................66

6.6 Exercises...............................................................................67

Chapter 7 Dynamic Pages..............................................................................69

7.1 Hello, World..........................................................................69

7.2 JSX........................................................................................71

7.3 Creating Components ...........................................................72

7.4 Developing with Parcel.........................................................73

7.5 Multiple Files........................................................................75

7.6 Exercises...............................................................................77

Chapter 8 Visualizing Data ............................................................................79

8.1 Vega-Lite...............................................................................79

8.2 Local Installation..................................................................83

8.3 Exercises...............................................................................84

Chapter 9 Promises ........................................................................................87

9.1 The Execution Queue ...........................................................87

9.2 Promises................................................................................90

9.3 Using Promises.....................................................................94

9.4 async and await..................................................................97

9.5 Exercises...............................................................................98

Chapter 10 Interactive Sites ...........................................................................103

10.1 But It Doesn’t Work............................................................104

10.2 Models and Views...............................................................107

10.3 Fetching Data......................................................................110

10.4 Exercises.............................................................................115
Contents ix
Chapter 11 Managing Data ............................................................................117

11.1 Data Formats.......................................................................117

11.2 Slicing Data ........................................................................118

11.3 Data Manager......................................................................119

11.4 Exercises.............................................................................122

Chapter 12 Creating aServer.........................................................................125

12.1 HTTP ..................................................................................125

12.2 Hello, Express.....................................................................127

12.3 HandlingMultiplePaths.....................................................128

12.4 Serving Files from Disk......................................................129

12.5 ContentTypes.....................................................................131

12.6 Exercises.............................................................................132

Chapter 13 Testing .........................................................................................133

13.1 Introducing Mocha..............................................................133

13.2 Refactoring .........................................................................134

13.3 Testing the Server ...............................................................135

13.4 Checking the HTML...........................................................138

13.5 Exercises.............................................................................139

Chapter 14 Using Data-Forge ........................................................................141

14.1 Basic Operations.................................................................142

14.2 Doing Calculations .............................................................144

14.3 Subsets................................................................................148

14.4 Aggregation ........................................................................150

14.5 In Real Life.........................................................................152

14.6 Exercises.............................................................................155

Chapter 15 Capstone Project..........................................................................157

15.1 Data Manager......................................................................157

15.2 Server..................................................................................160

15.3 API......................................................................................161

15.4 The Display.........................................................................162

15.5 The Tables...........................................................................165

15.6 TheChart............................................................................167

15.7 RunningIt...........................................................................168

15.8 Exercises.............................................................................171

Chapter 16 Finale...........................................................................................173

Bibliography .........................................................................................................175