A supercircle is created in the Cartesian coordinate system by the rule xn + yn = rn. With n=2, it is a circle. With n=4, it is a squircle, a shape with the properties of a square and a circle. As n gets higher, the shape resembles more to a square. A supercircle is a special case of a superellipse or Lamé curve.
Enter one value and choose the number of decimal places. Then click Calculate. Radius and diameter refer to the distance of opposite straight lines.
d = 2 * r
p ≈ 7.01769794356404 * r
A = 8 * Γ(5/4)² * r² / √π = 2 / √2 * S * r²
The calculation of p is very complicated and uses the gamma function Γ and the Meijer G-function.
Radius, diameter and perimeter have the same unit (e.g. meter), the area has this unit squared (e.g. square meter).