Added quadratic and cubic distributions data

[pasabanov]

Types of changes

• Feature

Related: #1 #3

Description

Added quadratic and cubic distributions data.

The "quadratic" distribution is given by:

$$ \mathrm{quadratic}(x) = \begin{cases} (x+1)^2 - 1, & x \leq 0 \\ -(x-1)^2 + 1, & x > 0 \end{cases} $$

The "cubic" distribution is given by:

$$ \mathrm{cubic}(x) = -0.5x^3 + 1.5x $$

The distribution of points is generated by applying these functions to the uniformly distributed points on the $[-1, 1]$ segment.

You can interact with these distributions on this Desmos graph: https://www.desmos.com/calculator/qdse58hzhp.