How do you input a Geometric function into a CAD system

[triage]

I have a math function which defines a geometric shape, that I wish to input to TurboCad for download into my CNC, to ultimately cut the pattern.

I can not figure out how to input a 2D object which is defined by a formula, aside from the ones already defined.

As in, a circle is r(sqr) = x(sqr) + y(sqr). I see that there are lots of typical geometric figures available, but I have a custom function which I need to input.

Anybody?

 

[Metalfixer]

I don't know if this will help, but the makers of TurboCad have a product called TurboCadCam V3, and offer a free trial,Links below:

http://www.turbocad.com/prodinfo.asp?mcid=314

http://nct.digitalriver.com/fulfill/0002.040

 

[IFRs]

One way is to create a script, if TC uses scripts.