How to use Data Packages from R

This tutorial demonstrates how to use Data Packages from R. We assume that you already know about Data Packages and its specifications.

Example

Let's consider "VIX - CBOE Volatility Index" data here. The VIX dataset is a key measure of market expectations of near-term volatility conveyed by S&P 500 stock index option prices introduced in 1993:

https://datahub.io/core/finance-vix

There are several ways to get data in R, but in this tutorial, we are going to use robust, high performance JSON Parser jsonlite library:

library("jsonlite")

json_file <- 'https://datahub.io/core/finance-vix/datapackage.json'
json_data <- fromJSON(paste(readLines(json_file), collapse=""))

# get list of all resources:
print(json_data$resources$name)

and you would get following table printed:

Our data is now available in different formats such as CSV, JSON, ZIP. To get it in the CSV format:

# print all tabular data(if exists any)
for(i in 1:length(json_data$resources$datahub$type)){
  if(json_data$resources$datahub$type[i]=='derived/csv'){
    path_to_file = json_data$resources$path[i]
    data <- read.csv(url(path_to_file))
    print(data)
  }
}