Random coloring

Parametric Curve(s)

$$$ \forall\alpha\in\{0,10\pi\}\quad1.6\leqslant\;k_{a}\;\leqslant4.4\quad0.2\leqslant\;k_{b}\;\leqslant0.5\quad \left \{ \begin{array}{r c l} \theta(\alpha)& = &\alpha \\ r(\alpha)& = &0.1\times\cos^2{(k_{a}\cdot\alpha)}-k_{b} \end{array}\right .$$$