Google Chart API Originally developed to suits internal need on their products, google released an open API where you can have a chart image generated on the fly. Using this service is very simple and require few programming knowledge. These components deals really effectively with mathematics, but they aren't interactive and their look can only be slightly customized. To include such chart on your website you only need to create an <img> tag and set the image url to point on a google-chart url. All the parameters are passed directly in the image path. The documentation site explain shortly, but effectively the different parameters that has to be passed for each charts type.     A more flexible way to display data without building everything from scratch is to use the Yahoo Astra Components. While they're not usable online directly, you easily download the source code and tweak their look at your taste in a more flexible way than the google components.  Javascript This new library use javascript in your html page to create image data of your charts. Because it uses JS to render the visual, it remains very limited. However, at one point, js img creation might be as effective as GD-library for PHP. And the work would be done on the client end so it canreduce the server ressources compared to charts generated by PHP classes. Like google, you get no interactivity(it's just an image). I still have to figure out the advantage of the JS charts yet. I would just stick to google charts for simple needs as these are compatible with flash and php. The javascript driven chart has to run in Javascript (forget flash, or wrapping it in PHP) and uses client resource only to replicate what can be done using google charts. |