This first short recipe discusses some general rules that will make your live easier when dealing with graph data.
It also sets you up with a few test files to use throughout the chapter.
Most data in graphs has a tabular form and will usually originate either from a spreadsheet or a database. It's possible to process pretty much any input format with ActionScript 3.0, but some will be easier than others. We will focus on data available in some spreadsheet format. See the There's more... section of this recipe for a discussion on databases.
The spreadsheet examples use Microsoft Excel because it is probably the most wide-spread application, but you can use any other spreadsheet application such as the free OpenOffice, ...