I am very new to python and python pint. I just want to know the supportable units of python pint. Also what is the meaning of the below representation:
{length: 1, time: -1}
Reference from pint unit. Also how do I print the available pint units for energy and temperature.
from pint import UnitRegistry
ureg = pint.UnitRegistry()
ureg.Unit
The keys of the dictionary are the dimensions, and the corresponding value is the power of that dimension. That is, {length: 1, time: -1} is the representation of velocity, and an example of a unit whose dimensionality is represented by the dictionary would be m/s. For acceleration, the representation would be {length: 1, time: -2}:
In [13]: ureg.Unit('m/s').dimensionality
Out[13]: <UnitsContainer({'[length]': 1, '[time]': -1})>
In [14]: ureg.Unit('m/s^2').dimensionality
Out[14]: <UnitsContainer({'[length]': 1, '[time]': -2})>
To get available units of a given dimensionality, use UnitRegistry.get_compatible_units; for instance, for your two examples:
In [9]: ureg.get_compatible_units('[energy]')
Out[9]:
frozenset({<Unit('electron_volt')>,
<Unit('rydberg')>,
<Unit('hartree')>,
<Unit('erg')>,
<Unit('joule')>,
<Unit('foot_pound')>,
<Unit('calorie')>,
<Unit('fifteen_degree_calorie')>,
<Unit('international_calorie')>,
<Unit('atmosphere_liter')>,
<Unit('thermochemical_british_thermal_unit')>,
<Unit('international_british_thermal_unit')>,
<Unit('british_thermal_unit')>,
<Unit('watt_hour')>,
<Unit('US_therm')>,
<Unit('therm')>,
<Unit('ton_TNT')>,
<Unit('tonne_of_oil_equivalent')>,
<Unit('quadrillion_Btu')>})
In [10]: ureg.get_compatible_units('[temperature]')
Out[10]:
frozenset({<Unit('degree_Rankine')>,
<Unit('kelvin')>,
<Unit('degree_Fahrenheit')>,
<Unit('degree_Reaumur')>,
<Unit('degree_Celsius')>,
<Unit('atomic_unit_of_temperature')>,
<Unit('planck_temperature')>})