Jan 022013
If you have read about geodesic domes, you have certainly seen expressions such as 1/2, 4/9, 5/9, 7/12 and so on. These fractions represent a portion of a sphere.
One way to identify a dome is called the profile, or percentage of sphere. This is expressed as a fraction. The denominator or bottom half of the fraction is equal to the frequency times three.
You cannot have an improper fraction, so if you need exactly half a sphere, you need an even numbered frequency. A 4 frequency half dome is a 6/12 dome. If a 4 frequency dome was a complete sphere, it would be a 12/12th’s sphere, or 1 complete sphere. A 5v dome less than half sphere is a 7/15 and more than a half sphere is 8/15; complete sphere 15/15th’s.
