Geometry Pack
Circle, ellipse (Ramanujan), hexagon, sphere.
Example
You enter
- Shape circle
- Radius 10
- Sector (deg) 90
You get
- Circumference Circumference 62.832
- Area Area 314.159
- Result 3 Sector area 78.540
No published worked example is on file for this calculation. It is checked against a hand-worked derivation of its method and an independent reference test.
Details, formula, and sources
Formula or tableClassical plane and solid geometry: circle, ellipse, hexagon, sphere area / perimeter / volume. Ellipse perimeter by Ramanujan's approximation P = pi (a + b) (1 + 3h / (10 + sqrt(4 - 3h))) with h = ((a - b)/(a + b))^2.
Source and editionClassical geometry; physical fact.
Free accessFree in geometry texts.
What governsEstimate. AHJ and licensed professional govern.
API field namesshape, radius, sector_deg, circumference, area, sector_area