Units in OMUSE

OMUSE code interfaces use quantities with units. This has the advantages that the units of any quantitiy is explicitly specified, and that automatic conversion can be done between different units.

Unit example:

from omuse.units import units

# units are attached to a number with the | operator:
velocity = 3 | units.m / units.s
mass = 0.002 | units.kg

print('velocity', velocity)

# a quantity can be separated into a number and a unit
print('number:', velocity.number, 'unit:', velocity.unit)
print()

print('mass', mass)

# get value in a different unit
print(mass.value_in(units.g), 'g')
print()

# arithmetic on quantities:
print('momentum:', mass * velocity)

output:

velocity 3 m / s
number: 3 unit: m / s

mass 0.002 kg
2.0 g

momentum: 0.006 m * kg * s**-1