[MacRuby-devel] scientific plotting engine

Good afternoon MacRuby'rs, Hopefully this question is not out of place, but if it is, my apologies. I just downloaded and installed MacRuby, and am new to this, although I do have an (old) background in programming as it relates to physics. I'm wondering if there is a general scientific plotting engine, e.g., GNUplot or something similar, that anyone could recommend for integrating into custom MacRuby-Cocoa programs (general/customizable 2D and 3D capabilities, and data visualization). In particular, is there an existing package that nicely takes advantage of OS X 10.6 frameworks within the context of the PDF kit? Thanks, Jonathan