Working with html, xml & json file formats
Create three files which store book content in HTML (table) format, XML format, and and JSON format. Load the information from each of the three sources into separate R data frames.
Are the three data frames identical?
Load packages
Evaluate books.html
readHTMLTable
doesn’t capture header names
fills sparse array (nulls) leftward
aligns columns nicely
adds no extraneous attributes
url <- "/Users/scottkarr/IS607Spring2016/hw8/more/books.html"
html <- readHTMLTable(url)
df <- data.frame(html)
kable(df, align='l')| NULL.V1 | NULL.V2 | NULL.V3 | NULL.V4 | NULL.V5 | NULL.V6 | NULL.V7 | NULL.V8 |
|---|---|---|---|---|---|---|---|
| Flashboys | Michael Lewis | Non-fiction | Thriller, Suspense, Sleuth | 14.31 | Chronicles the team that discovered market distortions from electronic trading. | NA | NA |
| title | author1 | author2 | author3 | type | genre | price | description |
| The Economistsâ Voice | Joseph E. Stiglitz | Aaron S. Edlin | J. Bradford Delong | Non-fiction | Economics, Public Policy | 18.95 | Compilation of contemporary economists on public policy issues. |
| title | author1 | type | genre | price | description | NA | NA |
| The Circle | David Eggers | Fiction | Thriller, Suspense, Dystopia, Contemporary issues | 9.49 | A âBrave New Worldâ for the modern surveillance state. | NA | NA |
- Evaluate books.xml
xmlToList
captures header names
aligns columns nicely
adds columns attributes
url <- "/Users/scottkarr/IS607Spring2016/hw8/more/books.xml"
df <- ldply(xmlToList(url), data.frame)
kable(df, align='l')| .id | text | title.text | title..attrs | text.1 | author1 | text.2 | type | text.3 | genre | text.4 | price | text.5 | description | text.6 | author2 | author3 | genre.1 | text.7 | text.8 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| book | Flashboys | en | Michael Lewis | Non-fiction | Thriller, Suspense, Sleuth | 14.31 | Chronicles the team that discovered market distortions from electronic trading. | NA | NA | NA | NA | NA | |||||||
| book | The Economists’ Voice | en | Joseph E. Stiglitz | NA | Non-fiction | 18.95 | Compilation of contemporary economists on public policy issues. | Aaron S. Edlin | J. Bradford Delong | Economics, Public Policy | |||||||||
| book | The Circle | en | David Eggers | NA | Fiction | 9.49 | A “Brave New World” for the modern surveillance state. | NA | NA | Thriller, Suspense, Dystopia, Contemporary issues | NA | NA |
- Evaluate books.json
fromJSON
captures header names
maintains table structure with nulls
columns displayed in wide format
adds no extraneous attributes
url <- "/Users/scottkarr/IS607Spring2016/hw8/more/books.json"
json <- fromJSON(paste(readLines(url), collapse=""))
df <- data.frame(json)
kable(df, align='l')| title | author1 | author2 | author3 | type | genre | price | description | title.1 | author1.1 | author2.1 | author3.1 | type.1 | genre.1 | price.1 | description.1 | title.2 | author1.2 | author2.2 | author3.2 | type.2 | genre.2 | price.2 | description.2 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Flashboys | Michael Lewis | Non-fiction | Thriller, Suspense, Sleuth | 14.31 | Chronicles the team that discovered market distortions from electronic trading. | The Economists’92 Voice | Joseph Stiglitz | Aaron S. Edlin | J. Bradford Delong | Non-fiction | Economics, Public Policy | 18.95 | Compilation of contemporary economists on public policy issues. | The Circle | David Eggers | Fiction | Thriller, Suspense, Dystopia, Contemporary Issues | 9.49 | A ‘Brave New World’ for the modern surveillance state. |