Units
Module containing global unit registry.
The Pint package supports arithmetic
of physical quantities, which are combinations of numerical values and units of
measurement. The units of a quantity come from Pint’s unit registry. This
module contains a unit registry, named u
, based on Pint’s unit registry.
It also defines a few additional units.
Frequently Used Units and Constants in u
Prefixes for Metric Units
pico- = 1e-12 = p-
nano- = 1e-9 = n-
micro- = 1e-6 = u- = µ-
milli- = 1e-3 = m-
centi- = 1e-2 = c-
deci- = 1e-1 = d-
deca- = 1e+1 = da-
hecto- = 1e2 = h-
kilo- = 1e3 = k-
mega- = 1e6 = M-
giga- = 1e9 = G-
tera- = 1e12 = T-
Units of Length
u.meter
=u.metre
=u.m
u.inch
u.foot
=u.ft
u.yard
=u.yd
u.mile
=u.mi
Units of Mass
u.gram
=u.g
u.metric_ton
=u.tonne
=u.t
u.ounce
=u.oz
u.pound
=u.lb
u.ton
u.atomic_mass_unit
=u.amu
Units of Time
u.second
=u.sec
=u.s
u.minute
=u.min
u.hour
=u.hr
u.day
u.week
u.year
Units of Temperature
u.kelvin
=u.degK
u.celsius
=u.degC
u.fahrenheit
=u.degF
Units of Angle
u.revolution
=u.rev
u.radian
=u.rad
u.degree
=u.deg
Units of Force
u.newton
=u.N
u.gram_force
=u.gf
u.kilogram_force
=u.kgf
u.pound_force
=u.lbf
u.ton_force
u.kip
Units of Frequency
u.hertz
=u.Hz
u.revolutions_per_minute
=u.rpm
Units of Money
u.dollar
=u.USD
u.lempira
=u.HNL
Units of Power
u.watt
=u.W
u.horsepower
=u.hp
Units of Pressure
u.pascal
=u.Pa
u.bar
u.atmosphere
=u.atm
u.torr
u.millimeter_Hg
=u.mmHg
Units of Volume
u.liter
=u.litre
=u.L
u.cubic_centimeter
=u.cc
u.gallon
=u.gal
u.quart
=u.qt
u.pint
=u.pt
u.cup
u.fluid_ounce
=u.floz
u.tablespoon
=u.tbsp
u.teaspoon
=tsp
Other Units
u.joule
=u.J
u.mole
=u.mol
=u.equivalent
=u.eq
u.NTU
= 1.47 * (u.mg
/u.L
)This turbidity-concentration relation applies to kaolinite clay and is obtained from Coagulation behavior of polyaluminum chloride (Wei et al., 2015).
Constants
u.gravity
u.molar_gas_constant
=u.R
u.avogadro_number
u.boltzmann_constant
Examples
>>> from aguaclara.core.units import u
>>> mass = 3 * u.kg
>>> height = 4 * u.m
>>> potential_energy = mass * height * u.gravity
>>> potential_energy
<Quantity(12.0, 'kilogram * meter * standard_gravity')>
>>> potential_energy.magnitude
12.0
>>> potential_energy.units
<Unit('kilogram * meter * standard_gravity')>
>>> potential_energy.to(u.joule)
<Quantity(117.6798, 'joule')>
>>> potential_energy.to_base_units()
<Quantity(117.6798, 'kilogram * meter ** 2 / second ** 2')>
- aguaclara.core.units.set_sig_figs(n=4)[source]
Set the default number of significant figures used to print Pint, Pandas and NumPy value quantities.
- Parameters:
n (int) – number of significant figures to display. Defaults to 4.
- Examples:
>>> from aguaclara.core.units import set_sig_figs, u >>> h = 2.5532532522352543*u.m >>> e = 25532532522352543*u.m >>> print('h before sigfig adjustment:',h) h before sigfig adjustment: 2.553 meter >>> print('e before sigfig adjustment:',e) e before sigfig adjustment: 2.553e+16 meter >>> set_sig_figs(10) >>> print('h after sigfig adjustment:',h) h after sigfig adjustment: 2.553253252 meter >>> print('e after sigfig adjustment:',e) e after sigfig adjustment: 2.553253252e+16 meter