next curve previous curve 2D curves 3D curves surfaces fractals polyhedra

SICI SPIRAL

Sici: initials of the Sine Integral (Si) and the Cosine Integral (Ci) (name given by Von Seggern in 1993).
Other name: Nielsen spiral.

 
Cartesian parametrization: .
Complex parametrization: .
Curvilinear abscissa: .
Cartesian tangential angle: .
Radius of curvature:
Intrinsic equation 1: .
Transcendental curve.

The ordinate of the asymptote is equal to the value of the Dirichlet integral .
Curve very similar to the portion of hyperbolic spiral: .
Compare also to the Cornu spiral.
 
next curve previous curve 2D curves 3D curves surfaces fractals polyhedra

© Robert FERRÉOL 2017