3 ms·
As an example of a completely different approach, this works out of the box in GNU units (showing both noninteractive and interactive usage): $ units GeV/c^2
by chrismorgan 3y ago
As an example of a completely different approach, this works out of the box in GNU units (showing both noninteractive and interactive usage):
$ units GeV/c^2
Definition: 1.7826619e-27 kg
$ units
Currency exchange rates from FloatRates (AUD base) on 2023-06-21
3761 units, 113 prefixes, 120 nonlinear units
You have: GeV/c^2
You want: [leave it blank]
Definition: 1.7826619e-27 kg
You have:
Because of these various definitions (a selection of lines pulled from /usr/share/units/definitions.units, I think I have included all the relevant ones recursively):
G- giga
giga- 1e9 # Greek gigas, "giant"
e 1.602176634e-19 C # electron charge (exact)
C coulomb
coulomb A s # charge
A ! # The ampere, symbol A, is the SI unit of electric current. […]
s ! # The second, symbol s, is the SI unit of time. It is defined […]
V volt
volt W/A # potential difference
W watt
watt J/s # power
J joule
joule N m # energy
N newton
newton kg m / s^2 # force
kg ! # The kilogram, symbol kg, is the SI unit of mass. It is […]
m ! # The metre, symbol m, is the SI unit of length. It is […]
c 299792458 m/s # speed of light in vacuum (exact)
(Fun thing, kg being the SI unit. Because of this, gram is defined as millikg!)
I really like the approach of specifying what you have, in absolutely whatever unit you like, and what you want (though I omitted that argument in this case, to just have it show the definition), and having it resolve it.
An excerpt from my ~/.units (which does have some serious stuff in it too, honest):
# Why not? (Question: is the slightly-Welsh-sounding ygazillion, yocto-gazillion, 10⁻²⁴ gazillion, greater or less than one?)
gazillion !
elephant 6.35 tonne
elephant_african 6.35 tonne
elephant_asian 5 tonne
# I want to have ranged values: elephant_baby 90–135 kg. This get complicated because of non-linear transformations, e.g. 2^(1–10) = 2–1024, but log₂-biased.
# baby_grand is also a baby