The Google Chart Tools API (application programming interface) is an extensive and growing set of data visualization tools that can add impressive visual impact to your data. If you’re picturing boring old pie and bar charts, then read on: interactivity, animation, and just plain fun are all part of the Google Chart Tools mix (Figure 8-1). In fact, there’s a lot more than just charts in Google Chart Tools:
Dials and “o-meter”-style displays
QR codes (2D bar codes for physical-world hyperlinks)
Lots of third-party visualizations
The ability to create your own custom visualizations
Figure 8-1. Your accountant won’t appreciate a chart like this
The API’s expansive nature easily warrants a book of its own, so this chapter covers just the essentials required to get started, enabling you to make better use of the official online documentation (http://code.google.com/apis/charttools/index.html) to explore further. We will also develop some useful functions and examples to help you get the most out of Google Chart Tools.
Google Chart Tools is split into two distinct sections:
Image charts are created with a specially formatted URL that is
passed to Google’s chart servers. The servers return a static image of
the chart for inclusion in web pages. Typically, the URL is used as
the value for an
src attribute. ...