Data607 Assignment 7

Working with XML and JSON in R

This assignment requires us to create objects in html, xml, and json and then load them into separate dataframes to compare.

I chose the subject of woodworking, and selected the top 3 books when searched on amazon.

I created the html, xml, and json in text files and saved them and uploaded them to the web.

Lets load some packages and take a look:

Packages

library(RCurl)
library(XML)
library(jsonlite)

HTML

html_o <- 'https://raw.githubusercontent.com/dataconsumer101/data607/master/books.html'
html_c <- getURLContent(html_o)
html_l <- readHTMLTable(html_c)
html_df <- html_l[[1]]
head(html_df)

##                                Title
## 1 The Complete Manual of Woodworking
## 2                  Essentail Joinery
## 3     Great Book of Woodworking Tips
##                                                                                            Subtitle
## 1                     A Detailed Guide to Design, Techniques, and Tools for the Beginner and Expert
## 2                                           The Fundamental Techniques Every Woodworker Should Know
## 3 Over 650 Ingenious Workshop Tips, Techniques, and Secrets from the Experts at American Woodworker
##                      Author Year     Cover Edition Pages Price
## 1 Albert Jackson, David Day 1996 Paperback       1   320 19.89
## 2            Marc Spagnuolo 2019 Paperback       1   216 17.75
## 3             Randy Johnson 2012 Paperback       1   336 15.99

XML

xml_o <- 'https://raw.githubusercontent.com/dataconsumer101/data607/master/books.xml'
xml_c <- getURLContent(xml_o)
xml_p <- xmlParse(xml_c)
xml_df <- xmlToDataFrame(xml_p)
head(xml_df)

##                                TITLE
## 1 The Complete Manual of Woodworking
## 2                  Essential Joinery
## 3     Great Book of Woodworking Tips
##                                                                                            SUBTITLE
## 1                     A Detailed Guide to Design, Techniques, and Tools for the Beginner and Expert
## 2                                           The Fundamental Techniques Every Woodworker Should Know
## 3 Over 650 Ingenious Workshop Tips, Techniques, and Secrets from the Experts at American Woodworker
##          AUTHOR  AUTHOR2 YEAR     COVER EDITION PAGES PRICE
## 1 AlbertJackson DavidDay 1996 Paperback       1   320 19.89
## 2 MarcSpagnuolo     <NA> 2019 Paperback       1   216 17.75
## 3  RandyJohnson     <NA> 2012 Paperback       1   336 15.99

JSON

json_o <- 'https://raw.githubusercontent.com/dataconsumer101/data607/master/books.json'
json_r <- fromJSON(json_o)
json_df <- json_r[[1]]
head(json_df)

##                                Title
## 1 The Complete Manual of Woodworking
## 2                  Essentail Joinery
## 3     Great Book of Woodworking Tips
##                                                                                            Subtitle
## 1                     A Detailed Guide to Design, Techniques, and Tools for the Beginner and Expert
## 2                                           The Fundamental Techniques Every Woodworker Should Know
## 3 Over 650 Ingenious Workshop Tips, Techniques, and Secrets from the Experts at American Woodworker
##                      Author Year     Cover Edition Pages Price
## 1 Albert Jackson, David Day 1996 Paperback       1   320 19.89
## 2            Marc Spagnuolo 2019 Paperback       1   216 17.75
## 3             Randy Johnson 2012 Paperback       1   336 15.99

Differences in Author

html_df[1,]$Author

## [1] Albert Jackson, David Day
## Levels: Albert Jackson, David Day Marc Spagnuolo Randy Johnson

xml_df[1,]$AUTHOR

## [1] "AlbertJackson"

xml_df[1,]$AUTHOR2

## [1] "DavidDay"

json_df[1,]$Author

## [[1]]
## [1] "Albert Jackson" "David Day"

For the most part, the data in each of these formats looks the same– as long as there is only one value per field.
If we look at the first book with 2 authors, we can see the differences in how the values appear. This is also influenced by how they were entered into each of the objects.