Automatic Rational Parameterization of Curves and Surfaces II: Cubics and Cubicoids
نویسندگان
چکیده
Cubicoids (degree 3 surfaces) always have a parameterization in tenos of rational functions, (a polynomial divided by another). On the other hand cubics (degree 3 plane curves) do not always have a rational parameterization. However they always have a parameterization of the type which allows a single square root of rational functions. [n this paper we describe algorithms to obtain rational and special parametric equations for the cubics and cubicoids. given the implicit equations. These algorithms have been implemented on a VAX-8600 using VAXIMA. t Departmr:nt of Mathematics, Purdue University. Research supported in part by grants from ONR and NSF. *Research supported in part by NSF grant ocr 85-21356.
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