Define here the number of decimal figures used to show the most important
types of real data. This is not related with the precision used internally,
which is always the maximum possible (double precision).
### Digits

The number of decimal figures used to show **Length**,
**Angle**, **Mass** and **Charge** real values is
defined here. This includes everything related with these
types of data, from atom radius to light position, from
cell angles to rotation step.

Less important types of real data, such as light attenuation or color components, have default values, defined at compile time.