Hello colorcurvature,

Yes, we can approximately fit any function. It is what I have done in my ERC trajectory prop here in the Freestuff. I have coded the sin, cos and tan function to orientate the prop and calculate tangential velocity.  The thing that I would like to know is the best number of keys and placement to approximate the function. There is surely some rules (ex: the peak and valley should be coded and the sampling frequency of point should be function of the degree of the funtion) but my search on the net did not result in clear responses. Perharps I should also look at the animation forum. 

Allstereo