Integrating Existing Data
Jon J. Raasch, Graham Murray, Vadim Ogievetsky, Joseph Lowery · 2014
After data is collected, you need techniques to retrieve it. Data can be stored in many different formats—plain text, CSV, XML, JSON, and others—but as long as it is in a digital format, chances are there are JavaScript and other server-side routines to access the information for representation. However, wherever possible, keep content (the data) separate from presentation (the charting). This chapter examines techniques for reading plain text files one line at a time as well as importing and parsing the ubiquitous CSV format. XML, short for Extensible Markup Language, is often used for storing data of all kinds. JSON is an abbreviation for JavaScript Object Notation and, although it is JavaScript-based, it is actually language- and platform-independent. JSON works nicely with a variety of visualization options. The chapter also provides an overview of the JSON syntax and techniques for incorporating JSON data into web pages.