are there any good statistic visualization libraries for the iphone?

I wonder if every developer would have to code statistic visualization by him/herself, or if there's a lib already that can be used to draw charts, curves, stats, etc. (like in the stock app for example)?

From stackoverflow

• Take a look at this graphing package, it will also compile on the iPhone:

  http://www.mpkju.fr/~graphview/page1/page1.html

  Note that I've not used it yet, I ran across it before and made a note of the potential usefulness of it.

• You might use the Google Charts API, and just use the images that come back from that:

  http://code.google.com/apis/chart/

  For instance, you can retrieve the bytes from this URL

  http://chart.apis.google.com/chart?cht=p3&chd=t:60,40&chs=250x100&chl=Hello|World

  and insert them into an NSImage, or just let the web view do the rendering for you.

• Core Plot is a cross-platform (Mac / iPhone) plotting framework being developed by a group of scientifically-minded Cocoa developers. It is based on Core Animation, and was advancing quite quickly the last time I checked in. You might want to read the mailing list archives to get an idea of the design goals and current state of the framework.