Working with online data and services

With the growing amount of data available from web-based sources, it is increasingly important for machine learning projects to be able to access and interact with online services. R is able to read data from online sources natively, with some caveats. Firstly, by default, R cannot access secure websites (those using the https:// rather than the http:// protocol). Secondly, it is important to note that most web pages do not provide data in a form that R can understand. The data would need to be parsed, or broken apart and rebuilt into a structured form, before it can be useful. We'll discuss the workarounds shortly.

However, if neither of these caveats applies (that is, if data are already online on a nonsecure website and in a tabular form, like CSV, that R can understand natively), then R's read.csv() and read.table() functions will be able to access data from the Web just as if it were on your local machine. Simply supply the full URL for...