# unyt.unit_symbols module¶

Predefined useful aliases to physical units

Note that all of these names can be imported from the top-level unyt namespace. For example:

>>> from unyt import cm, g, s
>>> data = [3, 4, 5]*g*cm/s
>>> print(data)
[3 4 5] cm*g/s


Unit Name

Dimensions

MKS value

CGS Value

LaTeX Representation

SI Prefixable?

Alternate Names

m

length

1.0 m

100.0 cm

\rm{m}

True

meter, Meter, metre, Metre

g

mass

0.001 kg

1.0 g

\rm{g}

True

gram, Gram, gramme, Gramme

s

time

1.0 s

1.0 s

\rm{s}

True

second, Second

K

temperature

1.0 K

1.0 K

\rm{K}

True

degree_kelvin, Degree_Kelvin, kelvin, Kelvin

angle

\rm{rad}

True

A

current_mks

1 A

2.9979e+09 statA

\rm{A}

True

ampere, Ampere, amp, Amp

cd

luminous_intensity

1.0 cd

1.0 cd

\rm{cd}

True

candela, Candela

mol

dimensionless

6.0221e+23 dimensionless

6.0221e+23 dimensionless

\rm{mol}

True

mole, Mole

dyn

force

1.0000e-05 N

1.0 dyn

\rm{dyn}

True

dyne, Dyne

erg

energy

1.0000e-07 J

1.0 erg

\rm{erg}

True

ergs, Ergs

Ba

pressure

0.1 Pa

1.0 dyn/cm**2

\rm{Ba}

True

barye, Barye

G

magnetic_field_cgs

0.0001 T

1 G

\rm{G}

True

gauss, Gauss

statC

magnetic_flux_cgs

3.3356e-10 C

1 statC

\rm{statC}

True

statcoulomb, Statcoulomb, esu, ESU, electrostatic_unit, Electrostatic_Unit

statA

current_cgs

3.3356e-10 A

1 statA

\rm{statA}

True

statampere, Statampere

statV

electric_potential_cgs

3.3356e-03 V

3.3356e-03 V

\rm{statV}

True

statvolt, Statvolt

statohm

v

8.9876e+11 Ω

8.9876e+11 Ω

\rm{statohm}

True

Mx

magnetic_flux_cgs

3.1623e-05 sqrt(kg)*m**(3/2)/s

1.0 statC

\rm{Mx}

True

maxwell, Maxwell

J

energy

1.0 J

1.0000e+07 erg

\rm{J}

True

joule, Joule

W

power

1.0 W

1.0000e+07 erg/s

\rm{W}

True

watt, Watt

Hz

1/(time)

1.0 Hz

1.0 1/s

\rm{Hz}

True

hertz, Hertz

N

force

1.0 N

1.0000e+05 dyn

\rm{N}

True

newton, Newton

C

charge_mks

1 C

2.9979e+09 statC

\rm{C}

True

coulomb, Coulomb

T

magnetic_field_mks

1 T

10000.0 G

\rm{T}

True

tesla, Tesla

Pa

pressure

1.0 Pa

10.0 dyn/cm**2

\rm{Pa}

True

pascal, Pascal

bar

pressure

1.0000e+05 Pa

1.0000e+06 dyn/cm**2

\rm{bar}

True

V

electric_potential_mks

1 V

2.9979e+02 statV

\rm{V}

True

volt, Volt

F

capacitance_mks

1.0 F

N/A

\rm{F}

True

H

inductance_mks

1.0 H

N/A

\rm{H}

True

henry, Henry

Ω

k

1 Ω

1.1127e-12 statohm

\Omega

True

ohm, Ohm

Wb

magnetic_flux_mks

1.0 Wb

N/A

\rm{Wb}

True

weber, Weber

lm

luminous_flux

1.0 lm

\rm{lm}

True

lumen, Lumen

lx

(angle)**2*(luminous_intensity)/(length)**2

\rm{lx}

True

lux

degC

temperature

274.15 K

274.15 K

^\circ\rm{C}

True

degree_celsius, Degree_Celsius, degree_Celsius, celcius, Celcius, celsius, Celsius, °C

delta_degC

temperature

1.0 K

1.0 K

\Delta^\circ\rm{C}

True

L

(length)**3

0.001 m**3

1.0000e+03 cm**3

\rm{L}

True

liter, Liter, litre, Litre, l

ha

(length)**2

10000.0 m**2

1.0000e+08 cm**2

\rm{ha}

False

hectare, Hectare

t

mass

1000.0 kg

1.0000e+06 g

\rm{t}

False

tonne, Tonne, metric_ton, Metric_Ton

mil

length

2.5400e-05 m

0.00254 cm

\rm{mil}

False

thou, Thou, thousandth, Thousandth

inch

length

0.0254 m

2.54 cm

\rm{in}

False

Inch, in

ft

length

0.3048 m

30.48 cm

\rm{ft}

False

foot, Foot

yd

length

0.9144 m

91.44 cm

\rm{yd}

False

yard, Yard

mile

length

1609.344 m

1.6093e+05 cm

\rm{mile}

False

Mile

nmi

length

1.8520e+03 m

1.8520e+05 cm

\rm{nmi}

False

nautical_mile, Nautical_Mile

mph

velocity

0.44704 m/s

44.704 cm/s

\rm{mph}

False

kt

velocity

5.1445e-01 m/s

5.1445e+01 cm/s

\rm{kt}

False

knot, Knot

acre

(length)**2

4.0469e+03 m**2

4.0469e+07 cm**2

\rm{acre}

False

Acre

furlong

length

201.168 m

2.0117e+04 cm

\rm{fur}

False

Furlong, fur

degF

temperature

2.5593e+02 K

2.5593e+02 K

^\circ\rm{F}

False

Degf, degree_fahrenheit, Degree_Fahrenheit, degree_Fahrenheit, fahrenheit, Fahrenheit, °F

delta_degF

temperature

5.5556e-01 K

5.5556e-01 K

\Delta^\circ\rm{F}

False

Delta_Degf

R

temperature

5.5556e-01 K

5.5556e-01 K

^\circ\rm{R}

False

degree_rankine, Degree_Rankine, rankine, Rankine

lbf

force

4.4482e+00 N

4.4482e+05 dyn

\rm{lbf}

False

pound_force, Pound_Force

kip

force

4.4482e+03 N

4.4482e+08 dyn

\rm{kip}

False

kilopound, Kilopound, kipf, Kipf

lb

mass

4.5359e-01 kg

4.5359e+02 g

\rm{lb}

False

pound, Pound, pound_mass, Pound_Mass, lbm

atm

pressure

1.0132e+05 Pa

1.0132e+06 dyn/cm**2

\rm{atm}

False

atmosphere, Atmosphere

hp

power

7.4570e+02 W

7.4570e+09 erg/s

\rm{hp}

False

horsepower, Horsepower

oz

mass

2.8350e-02 kg

2.8350e+01 g

\rm{oz}

False

ounce, Ounce

ton

mass

9.0718e+02 kg

9.0718e+05 g

\rm{US ton}

False

ton_US, ton_US_short, short_ton, Short_Ton

ton_UK

mass

1.0160e+03 kg

1.0160e+06 g

\rm{UK ton}

False

ton_US_long, long_ton, Long_Ton

slug

mass

1.4594e+01 kg

1.4594e+04 g

\rm{slug}

False

Slug

fl_oz_US

(length)**3

2.9574e-05 m**3

2.9574e+01 cm**3

\rm{US fl oz}

False

fluid_ounce_US

fl_oz_UK

(length)**3

2.8413e-05 m**3

2.8413e+01 cm**3

\rm{UK fl oz}

False

fluid_ounce_UK

pt_US

(length)**3

4.7318e-04 m**3

4.7318e+02 cm**3

\rm{US pt}

False

pint_US

pt_UK

(length)**3

5.6826e-04 m**3

5.6826e+02 cm**3

\rm{UK pt}

False

pint_UK

qt_US

(length)**3

9.4635e-04 m**3

9.4635e+02 cm**3

\rm{US qt}

False

quart_US

qt_UK

(length)**3

1.1365e-03 m**3

1.1365e+03 cm**3

\rm{UK qt}

False

quart_UK

gal_US

(length)**3

3.7854e-03 m**3

3.7854e+03 cm**3

\rm{US gal}

False

gallon_US

gal_UK

(length)**3

4.5461e-03 m**3

4.5461e+03 cm**3

\rm{UK gal}

False

gallon_UK

cal

energy

4.184 J

4.1840e+07 erg

\rm{cal}

True

calorie, Calorie

BTU

energy

1.0551e+03 J

1.0551e+10 erg

\rm{BTU}

False

british_thermal_unit, British_Thermal_Unit, btu

MMBTU

energy

1.0551e+09 J

1.0551e+16 erg

\rm{MMBTU}

False

Mmbtu, mmbtu

therm

energy

1.0551e+08 J

1.0551e+15 erg

\rm{therm}

False

Therm, therms, Therms

energy

1.0551e+18 J

1.0551e+25 erg

\rm{quad}

False

Wh

energy

3600.0 J

3.6000e+10 erg

\rm{Wh}

True

watt_hour, Watt_Hour, watt_hours, Watt_Hours

pli

specific_flux

1.7513e+02 kg/s**2

1.7513e+05 g/s**2

\rm{pli}

False

pounds_per_inch, Pounds_Per_Inch

plf

specific_flux

1.4594e+01 kg/s**2

1.4594e+04 g/s**2

\rm{plf}

False

pounds_per_ft, Pounds_Per_Ft

psi

pressure

6.8948e+03 Pa

6.8948e+04 dyn/cm**2

\rm{psi}

False

pounds_per_square_inch, Pounds_Per_Square_Inch

psf

pressure

4.7880e+01 Pa

4.7880e+02 dyn/cm**2

\rm{psf}

False

pounds_per_square_ft, Pounds_Per_Square_Ft

kli

specific_flux

1.7513e+05 kg/s**2

1.7513e+08 g/s**2

\rm{kli}

False

kips_per_inch, Kips_Per_Inch

klf

specific_flux

1.4594e+04 kg/s**2

1.4594e+07 g/s**2

\rm{klf}

False

kips_per_ft, Kips_Per_Ft

ksi

pressure

6.8948e+06 Pa

6.8948e+07 dyn/cm**2

\rm{ksi}

False

kips_per_square_inch, Kips_Per_Square_Inch

ksf

pressure

4.7880e+04 Pa

4.7880e+05 dyn/cm**2

\rm{ksf}

False

kips_per_square_ft, Kips_Per_Square_Ft

smoot

length

1.7018 m

170.18 cm

\rm{smoot}

False

Smoot

dimensionless

dimensionless

1.0 dimensionless

1.0 dimensionless

False

Dimensionless, _,

%

dimensionless

0.01 dimensionless

0.01 dimensionless

\%

False

percent, Percent

min

time

60.0 s

60.0 s

\rm{min}

False

minute, Minute

hr

time

3600.0 s

3600.0 s

\rm{hr}

False

hour, Hour

day

time

8.6400e+04 s

8.6400e+04 s

\rm{d}

False

d

week

time

6.0480e+05 s

6.0480e+05 s

\rm{week}

False

Week

fortnight

time

1.2096e+06 s

1.2096e+06 s

\rm{fortnight}

False

Fortnight

yr

time

3.1558e+07 s

3.1558e+07 s

\rm{yr}

True

year, Year

c

velocity

2.9979e+08 m/s

2.9979e+10 cm/s

\rm{c}

False

Msun

mass

1.9884e+30 kg

1.9884e+33 g

\rm{M}_\odot

False

msun, m_sun, M_Sun, M_sun, m_Sun, solar_mass, Solar_Mass, solMass, mass_sun, Mass_Sun

Rsun

length

6.9550e+08 m

6.9550e+10 cm

\rm{R}_\odot

False

Lsun

power

3.8270e+26 W

3.8270e+33 erg/s

\rm{L}_\odot

False

lsun, l_sun, L_Sun, L_sun, l_Sun, solar_luminosity, Solar_Luminosity, solLuminosity

Tsun

temperature

5870.0 K

5870.0 K

\rm{T}_\odot

False

t_sun, T_Sun, tsun, T_sun, t_Sun, solar_temperature, Solar_Temperature, solTemperature

Zsun

dimensionless

0.01295 dimensionless

0.01295 dimensionless

\rm{Z}_\odot

False

z_sun, Z_Sun, zsun, Z_sun, z_Sun, solar_metallicity, Solar_Metallicity, solMetallicity

Zsun_angr

dimensionless

0.01937 dimensionless

0.01937 dimensionless

\rm{Z}_\odot

False

Zsun_Angr

Zsun_aspl

dimensionless

0.01337 dimensionless

0.01337 dimensionless

\rm{Z}_\odot

False

Zsun_Aspl

Zsun_feld

dimensionless

0.01909 dimensionless

0.01909 dimensionless

\rm{Z}_\odot

False

Zsun_Feld

Zsun_lodd

dimensionless

0.01321 dimensionless

0.01321 dimensionless

\rm{Z}_\odot

False

Zsun_Lodd

Mjup

mass

1.8985e+27 kg

1.8985e+30 g

\rm{M}_{\rm{Jup}}

False

m_jup, M_Jup, jupiter_mass, Jupiter_Mass

Mearth

mass

6.0456e+24 kg

6.0456e+27 g

\rm{M}_\oplus

False

m_earth, M_Earth, earth_mass, Earth_Mass

Rjup

length

6.9911e+07 m

6.9911e+09 cm

\rm{R}_\mathrm{Jup}

False

Rearth

length

6.3710e+06 m

6.3710e+08 cm

\rm{R}_\oplus

False

AU

length

1.4960e+11 m

1.4960e+13 cm

\rm{AU}

False

au, astronomical_unit, Astronomical_Unit

ly

length

9.4605e+15 m

9.4605e+17 cm

\rm{ly}

False

light_year, Light_Year

pc

length

3.0857e+16 m

3.0857e+18 cm

\rm{pc}

True

parsec, Parsec

degree

angle

^\circ

False

Degree, deg

arcmin

angle

\rm{arcmin}

False

Arcmin, arcminute, Arcminute

arcsec

angle

\rm{arcsec}

False

Arcsec, arcsecond, Arcsecond

mas

angle

\rm{mas}

False

milliarcsecond, Milliarcsecond

hourangle

angle

\rm{HA}

False

Hourangle, HA

sr

(angle)**2

\rm{sr}

False

lat

angle

\rm{Latitude}

False

latitude, Latitude, degree_latitude, Degree_Latitude

lon

angle

\rm{Longitude}

False

longitude, Longitude, degree_longitude, Degree_Longitude

rpm

angular_frequency

\rm{RPM}

False

rev

angle

\rm{rev}

False

revolution, Revolution

eV

energy

1.6022e-19 J

1.6022e-12 erg

\rm{eV}

True

electronvolt, Electronvolt

amu

mass

1.6605e-27 kg

1.6605e-24 g

\rm{amu}

False

atomic_mass_unit, Atomic_Mass_Unit

Å

length

1.0000e-10 m

1.0000e-08 cm

\AA

False

angstrom, Angstrom

Jy

specific_flux

1.0000e-26 kg/s**2

1.0000e-23 g/s**2

\rm{Jy}

True

jansky, Jansky

counts

dimensionless

1.0 dimensionless

1.0 dimensionless

\rm{counts}

False

Counts, count, Count

photons

dimensionless

1.0 dimensionless

1.0 dimensionless

\rm{photons}

False

Photons, photon, Photon

me

mass

9.1094e-31 kg

9.1094e-28 g

m_e

False

electron_mass, Electron_Mass

mp

mass

1.6737e-27 kg

1.6737e-24 g

m_p

False

proton_mass, Proton_Mass

Sv

specific_energy

1.0 J/kg

10000.0 erg/g

\rm{Sv}

True

sievert, Sievert

Ry

energy

2.1799e-18 J

2.1799e-11 erg

\rm{Ry}

False

rayleigh

count_intensity

\rm{R}

False

Rayleigh

lambert

luminance

3.1831e+03 cd/m**2

3.1831e-01 cd/cm**2

\rm{L}

False

Lambert

nt

luminance

1.0 cd/m**2

0.0001 cd/cm**2

\rm{nt}

False

nit

m_pl

mass

2.1765e-08 kg

2.1765e-05 g

m_{\rm{P}}

False

planck_mass, Planck_Mass

l_pl

length

1.6162e-35 m

1.6162e-33 cm

\ell_{\rm{P}}

False

planck_length, Planck_Length

t_pl

time

5.3912e-44 s

5.3912e-44 s

t_{\rm{P}}

False

planck_time, Planck_Time

T_pl

temperature

1.4168e+32 K

1.4168e+32 K

T_{\rm{P}}

False

planck_temperature, Planck_Temperature

q_pl

charge_mks

1.8755e-18 C

N/A

q_{\rm{P}}

False

planck_charge, Planck_Charge

E_pl

energy

1.9561e+09 J

1.9561e+16 erg

E_{\rm{P}}

False

planck_energy, Planck_Energy

m_geom

mass

1.9884e+30 kg

1.9884e+33 g

\rm{M}_\odot

False

l_geom

length

1.4766e+03 m

1.4766e+05 cm

\rm{M}_\odot

False

t_geom

time

4.9253e-06 s

4.9253e-06 s

\rm{M}_\odot

False

B

logarithmic

1.1513e+00 Np

1.1513e+00 Np

\rm{B}

True

bel

Np

logarithmic

1.0 Np

1.0 Np

\rm{Np}

True

neper, Neper