Units are case-sensitive. Generally only units with useful conversions
are defined. Unit tracking or aggregation is generally not desired. If
no unit is defined, the default is assumed. The following is a list of
standard units.

## Length

- Default is meter. Permissible units are:
- m
- mil, mils
- in, inch
- ft, foot, feet
- mi, mile

## Angle

- Default is degrees. Permissible units are:
- deg, degree, degrees
- rad, radian, radians

## Time

- Default is seconds. Permissible units are:
- day, dy, days
- hour, hours, hr, hrs
- min, minutes, minute
- s, second, seconds

## Percent

- Permissible units are:
- %

### Log

- Permissible units are:
- dB: linear translation assumes "voltage" dB, e.g. -3dB is 0.7071 (convention for S-Parameters)

### Metric

Default is no modifier. If the unit is not one of the above, then the first character in the unit will set the multiplier. Therefore 'nF', 'nH', 'n', and 'no_unit' are all equivalent to Mason (obviously the last one would cause confusing results for the unwary designer).- f (1e-15)
- p (1e-12)
- n (1e-9)
- u (1e-6)
- m (1e-3)
- c (1e-2)
- d (1e-1)
- D (1e1)
- k (1e3)
- M (1e6)
- G (1e9)
- T (1e12)