how to create plots (non-flash) with mouse-over info boxes on the fly for the web?

I'm thinking abou开发者_开发技巧t creating a tool to visualize scientific data on a website. For this, the user enters some query string and out comes a simple (x,y)-plot (similar to this)

I know that using Matplotlib, one can generate graphics on the fly for python. However, this doesn't solve the need for some custom java-script code to display the info boxes. I also came across google chart tools, which are very close to what I need. The problem here is, that the code needs to be fetched from google, which my employer won't like.

What would be the best OSS library for python, Java, PHP (or Java-script) out there to meet my requirements?

Thanks, Chris

If you need dynamic elements without flash or Java applet then JavaScript is the best choice. To create plots you could use HTML5 canvas element.

Capturing mouse events is JS is trivial...