# Ellipse Calculator

An ellipse is a closed curve on a plane, which can be obtained as the intersection of a plane and a circular cylinder or as an orthogonal projection of a circle onto a plane. The major semi-axis is the distance between the center and the point on the ellipse furthest from it. The minor semimajor axis is the distance between the center and the point on the ellipse closest to it. The major and minor axes stand vertically to each other. Linear eccentricity is the distance between the focal points and the center. The circle is calculated using an approximation formula (the Second Approximation of Srinivasa Ramanujan), which is very accurate up to ε An exact calculation can be performed using elliptic integrals (Jacobi integrals), the values of which can be taken from tables. Cb is about 7 times the best estimate using the Second Ramanujan Approximation made by Jurgen Beck. This is based on an astroid approximation and has not yet been verified.

**Ellipse Calculator**

**Large semi - axis(a)**

**Smaller half- axis (b)**

**Axial ratio (a/b)**

**Linear eccentricity (e)**

**Numerical eccentricity (ε)**

**Circumference length (C)**

**Circle after Beck (Cb)**

**Square (S)**