The file hknots.zip contains POV-Ray 3.1 files for Aaron K. Trautwein's Fourier "harmonic" parameterizations of knots 31, 41, 51, 52, 61, 62, 63, 71, 72, 73, 74, 75, 76, 77, Granny knot, and Square Knot
The idea is that the parameterization of each knot (a curve) is three Fourier series (one for each of x, y, and z).
Macros for making the knots, computing tangents and curvatures along the knot curves are included.
UP to Edna Dornblazer Institute of Theoretical Cosmetology and Mad Secretarial Sciences