Jess Maertterer once wrote a Math plugin for Rhino that would graph mathematical equations. I’m not sure if it ever got updated to work in newer versions of Rhino.
http://www.rhino3.de/_develop/__v3_plugins/math/index.shtml
That, in combination with something like this:
http://www.mathematische-basteleien.de/spiral.htm
may allow you to get what you’re after.