This is documentation for an old release of SciPy (version 1.5.3). Read this page in the documentation of the latest stable release (version 1.15.1).
Constants (scipy.constants
)¶
Physical and mathematical constants and units.
Mathematical constants¶
|
Pi |
|
Golden ratio |
|
Golden ratio |
Physical constants¶
|
speed of light in vacuum |
|
speed of light in vacuum |
|
the magnetic constant \(\mu_0\) |
|
the electric constant (vacuum permittivity), \(\epsilon_0\) |
|
the Planck constant \(h\) |
|
the Planck constant \(h\) |
|
\(\hbar = h/(2\pi)\) |
|
Newtonian constant of gravitation |
|
Newtonian constant of gravitation |
|
standard acceleration of gravity |
|
elementary charge |
|
elementary charge |
|
molar gas constant |
|
molar gas constant |
|
fine-structure constant |
|
fine-structure constant |
|
Avogadro constant |
|
Avogadro constant |
|
Boltzmann constant |
|
Boltzmann constant |
|
Stefan-Boltzmann constant \(\sigma\) |
|
Stefan-Boltzmann constant \(\sigma\) |
|
Wien displacement law constant |
|
Rydberg constant |
|
electron mass |
|
electron mass |
|
proton mass |
|
proton mass |
|
neutron mass |
|
neutron mass |
Constants database¶
In addition to the above variables, scipy.constants
also contains the
2018 CODATA recommended values [CODATA2018] database containing more physical
constants.
|
Value in physical_constants indexed by key |
|
Unit in physical_constants indexed by key |
|
Relative precision in physical_constants indexed by key |
|
Return list of physical_constant keys containing a given string. |
Accessing a constant no longer in current CODATA data set |
-
scipy.constants.
physical_constants
¶ Dictionary of physical constants, of the format
physical_constants[name] = (value, unit, uncertainty)
.
Available constants:
|
6.6446573357e-27 kg |
|
5.9719201914e-10 J |
|
3727.3794066 MeV |
|
4.001506179127 u |
|
0.0040015061777 kg mol^-1 |
|
4.001506179127 |
|
7294.29954142 |
|
3.97259969009 |
|
1.00001495e-10 m |
|
1.6605390666e-27 kg |
|
1.4924180856e-10 J |
|
931.49410242 MeV |
|
931494102.42 eV |
|
34231776.874 E_h |
|
2.25234271871e+23 Hz |
|
751300661040000.0 m^-1 |
|
1.4924180856e-10 J |
|
10809540191600.0 K |
|
1.6605390666e-27 kg |
|
3.2063613061e-53 C^3 m^3 J^-2 |
|
6.2353799905e-65 C^4 m^4 J^-3 |
|
1.054571817e-34 J s |
|
1.602176634e-19 C |
|
1081202384570.0 C m^-3 |
|
0.00662361823751 A |
|
8.4783536255e-30 C m |
|
514220674763.0 V m^-1 |
|
9.7173624292e+21 V m^-2 |
|
1.64877727436e-41 C^2 m^2 J^-1 |
|
27.211386245988 V |
|
4.4865515246e-40 C m^2 |
|
4.3597447222071e-18 J |
|
8.2387234983e-08 N |
|
5.29177210903e-11 m |
|
1.85480201566e-23 J T^-1 |
|
235051.756758 T |
|
7.8910366008e-29 J T^-2 |
|
9.1093837015e-31 kg |
|
1.9928519141e-24 kg m s^-1 |
|
1.11265005545e-10 F m^-1 |
|
2.4188843265857e-17 s |
|
2187691.26364 m s^-1 |
|
6.02214076e+23 mol^-1 |
|
9.2740100783e-24 J T^-1 |
|
5.788381806e-05 eV T^-1 |
|
13996244936.1 Hz T^-1 |
|
46.686447783 m^-1 T^-1 |
|
0.67171381563 K T^-1 |
|
5.29177210903e-11 m |
|
1.380649e-23 J K^-1 |
|
8.617333262e-05 eV K^-1 |
|
20836619120.0 Hz K^-1 |
|
69.50348004 m^-1 K^-1 |
|
2.8179403262e-15 m |
|
2.42631023867e-12 m |
|
7.748091729e-05 S |
|
1.00000008887 A |
|
1.00000008887 C |
|
0.9999999822 F |
|
1.00000001779 H |
|
483597900000000.0 Hz V^-1 |
|
1.00000001779 ohm |
|
1.00000010666 V |
|
25812.807 ohm |
|
1.00000019553 W |
|
1.00207697e-13 m |
|
0.8574382338 |
|
4.330735094e-27 J T^-1 |
|
0.000466975457 |
|
0.8574382338 |
|
3.3435837724e-27 kg |
|
3.00506323102e-10 J |
|
1875.61294257 MeV |
|
2.013553212745 u |
|
0.00201355321205 kg mol^-1 |
|
2.013553212745 |
|
2.12799e-15 m |
|
-0.0004664345551 |
|
3670.48296788 |
|
-0.44820653 |
|
0.30701220939 |
|
1.99900750139 |
|
-175882001076.0 C kg^-1 |
|
-2.00231930436256 |
|
176085963023.0 s^-1 T^-1 |
|
28024.9514242 MHz T^-1 |
|
-9.2847647043e-24 J T^-1 |
|
0.00115965218128 |
|
-1.00115965218128 |
|
-1838.28197188 |
|
9.1093837015e-31 kg |
|
8.1871057769e-14 J |
|
0.51099895 MeV |
|
0.000548579909065 u |
|
5.4857990888e-07 kg mol^-1 |
|
0.000548579909065 |
|
0.0001370933554787 |
|
864.058257 |
|
-658.2275971 |
|
1.602176634e-19 J |
|
1.07354410233e-09 u |
|
0.036749322175655 E_h |
|
241798924200000.0 Hz |
|
806554.3937 m^-1 |
|
1.602176634e-19 J |
|
11604.51812 K |
|
1.782661921e-36 kg |
|
-2143.9234915 |
|
0.0002724437107462 |
|
0.0001819543074573 |
|
206.7669883 |
|
0.00483633169 |
|
960.9205 |
|
0.00054386734424 |
|
-658.21068789 |
|
0.000544617021487 |
|
0.000287585 |
|
0.0001819200062251 |
|
1.602176634e-19 C |
|
1519267447000000.0 A J^-1 |
|
96485.33212 C mol^-1 |
|
1.1663787e-05 GeV^-2 |
|
0.0072973525693 |
|
3.741771852e-16 W m^2 |
|
1.191042972e-16 W m^2 sr^-1 |
|
4.3597447222071e-18 J |
|
27.211386245988 eV |
|
2.92126232205e-08 u |
|
27.211386245988 eV |
|
6579683920502000.0 Hz |
|
21947463.13632 m^-1 |
|
4.3597447222071e-18 J |
|
315775.02480407 K |
|
4.8508702095432e-35 kg |
|
-4.255250615 |
|
-1.074617532e-26 J T^-1 |
|
-0.001158740958 |
|
-2.127625307 |
|
5.0064127796e-27 kg |
|
4.4995394125e-10 J |
|
2808.39160743 MeV |
|
3.014932247175 u |
|
0.00301493224613 kg mol^-1 |
|
3.014932247175 |
|
5.996743e-05 |
|
5495.88528007 |
|
2.99315267167 |
|
4.4398216652e-24 u |
|
4.135667696e-15 eV |
|
1.519829846057e-16 E_h |
|
3.3356409519815204e-09 m^-1 |
|
6.62607015e-34 J |
|
4.799243073e-11 K |
|
7.372497323e-51 kg |
|
9192631770.0 Hz |
|
137.035999084 |
|
1.3310250501e-15 u |
|
1.239841984e-06 eV |
|
4.556335252912e-08 E_h |
|
299792458.0 Hz |
|
1.986445857e-25 J |
|
0.01438776877 K |
|
2.210219094e-42 kg |
|
12906.40372 ohm |
|
483597848400000.0 Hz V^-1 |
|
6700535256.5 u |
|
6.241509074e+18 eV |
|
2.2937122783963e+17 E_h |
|
1.509190179e+33 Hz |
|
5.034116567e+24 m^-1 |
|
7.242970516e+22 K |
|
1.1126500560536185e-17 kg |
|
9.2510873014e-14 u |
|
8.617333262e-05 eV |
|
3.1668115634556e-06 E_h |
|
20836619120.0 Hz |
|
69.50348004 m^-1 |
|
1.380649e-23 J |
|
1.536179187e-40 kg |
|
6.0221407621e+26 u |
|
5.609588603e+35 eV |
|
2.0614857887409e+34 E_h |
|
1.356392489e+50 Hz |
|
4.524438335e+41 m^-1 |
|
8.987551787368176e+16 J |
|
6.50965726e+39 K |
|
5.431020511e-10 m |
|
1.920155716e-10 m |
|
2.651645804e+25 m^-3 |
|
2.686780111e+25 m^-3 |
|
683.0 lm W^-1 |
|
2.067833848e-15 Wb |
|
1.00209952e-13 m |
|
8.314462618 J mol^-1 K^-1 |
|
0.00099999999965 kg mol^-1 |
|
0.0119999999958 kg mol^-1 |
|
3.990312712e-10 J Hz^-1 mol^-1 |
|
0.02271095464 m^3 mol^-1 |
|
0.02241396954 m^3 mol^-1 |
|
1.205883199e-05 m^3 mol^-1 |
|
1.17344411e-14 m |
|
-2.0023318418 |
|
-4.4904483e-26 J T^-1 |
|
0.00116592089 |
|
-0.00484197047 |
|
-8.89059703 |
|
1.883531627e-28 kg |
|
1.692833804e-11 J |
|
105.6583755 MeV |
|
0.1134289259 u |
|
0.0001134289259 kg mol^-1 |
|
206.768283 |
|
0.112454517 |
|
-3.183345142 |
|
0.1126095264 |
|
0.0594635 |
|
1.054571817e-34 J s |
|
6.582119569e-16 eV s |
|
8.1871057769e-14 J |
|
0.51099895 MeV |
|
3.8615926796e-13 m |
|
9.1093837015e-31 kg |
|
2.730924488e-22 kg m s^-1 |
|
0.5109989461 MeV/c |
|
1.28808866819e-21 s |
|
299792458.0 m s^-1 |
|
1.31959090581e-15 m |
|
-3.82608545 |
|
183247171.0 s^-1 T^-1 |
|
29.1646931 MHz T^-1 |
|
-9.6623651e-27 J T^-1 |
|
-0.00104187563 |
|
-1.91304273 |
|
1.67492749804e-27 kg |
|
1.50534976287e-10 J |
|
939.56542052 MeV |
|
1.00866491595 u |
|
0.0010086649156 kg mol^-1 |
|
1.00866491595 |
|
-0.68499694 |
|
0.00104066882 |
|
1838.68366173 |
|
8.89248406 |
|
-0.68497934 |
|
2.30557435e-30 kg |
|
2.07214689e-13 J |
|
1.29333236 MeV |
|
0.00138844933 u |
|
1.00137841931 |
|
0.528779 |
|
6.6743e-11 m^3 kg^-1 s^-2 |
|
6.70883e-39 (GeV/c^2)^-2 |
|
5.0507837461e-27 J T^-1 |
|
3.15245125844e-08 eV T^-1 |
|
0.0254262341353 m^-1 T^-1 |
|
0.00036582677756 K T^-1 |
|
7.6225932291 MHz T^-1 |
|
6.62607015e-34 J Hz^-1 |
|
4.135667696e-15 eV Hz^-1 |
|
1.616255e-35 m |
|
2.176434e-08 kg |
|
1.22089e+19 GeV |
|
1.416784e+32 K |
|
5.391247e-44 s |
|
95788331.56 C kg^-1 |
|
1.32140985539e-15 m |
|
5.5856946893 |
|
267522187.44 s^-1 T^-1 |
|
42.577478518 MHz T^-1 |
|
1.41060679736e-26 J T^-1 |
|
0.0015210322023 |
|
2.79284734463 |
|
2.5689e-05 |
|
1.67262192369e-27 kg |
|
1.50327761598e-10 J |
|
938.27208816 MeV |
|
1.007276466621 u |
|
0.00100727646627 kg mol^-1 |
|
1.007276466621 |
|
8.414e-16 m |
|
1836.15267343 |
|
8.88024337 |
|
-1.45989805 |
|
0.99862347812 |
|
0.528051 |
|
0.00036369475516 m^2 s^-1 |
|
0.00072738951032 m^2 s^-1 |
|
3.8615926796e-13 m |
|
1.867594306e-15 m |
|
2.1001941552e-16 m |
|
1.054571817e-34 J s |
|
6.582119569e-16 eV s |
|
197.3269804 MeV fm |
|
2.10308910336e-16 m |
|
1.110538e-16 m |
|
10973731.56816 m^-1 |
|
3289841960250800.0 Hz |
|
13.605693122994 eV |
|
2.1798723611035e-18 J |
|
-1.15170753706 |
|
-1.16487052358 |
|
0.01438776877 m K |
|
203789456.9 s^-1 T^-1 |
|
32.43409942 MHz T^-1 |
|
-1.07455309e-26 J T^-1 |
|
-0.001158671471 |
|
-2.127497719 |
|
-0.7617665618 |
|
-0.7617861313 |
|
267515315.1 s^-1 T^-1 |
|
42.57638474 MHz T^-1 |
|
1.41057056e-26 J T^-1 |
|
0.001520993128 |
|
2.792775599 |
|
2.02e-08 |
|
2.414e-08 |
|
299792458.0 m s^-1 |
|
9.80665 m s^-2 |
|
101325.0 Pa |
|
100000.0 Pa |
|
5.670374419e-08 W m^-2 K^-4 |
|
6.97771e-16 m |
|
1776.86 MeV |
|
3.16754e-27 kg |
|
2.84684e-10 J |
|
1.90754 u |
|
0.00190754 kg mol^-1 |
|
3477.23 |
|
16.817 |
|
1.89115 |
|
1.89376 |
|
6.6524587321e-29 m^2 |
|
5.957924931 |
|
1.5046095202e-26 J T^-1 |
|
0.0016223936651 |
|
2.9789624656 |
|
5.0073567446e-27 kg |
|
4.500387806e-10 J |
|
2808.92113298 MeV |
|
3.01550071621 u |
|
0.00301550071517 kg mol^-1 |
|
3.01550071621 |
|
1.0666399191 |
|
5496.92153573 |
|
2.99371703414 |
|
1.6605390666e-27 kg |
|
8.8541878128e-12 F m^-1 |
|
1.25663706212e-06 N A^-2 |
|
25812.80745 ohm |
|
0.88153 |
|
0.2229 |
|
58789257570.0 Hz K^-1 |
|
0.002897771955 m K |
Units¶
SI prefixes¶
|
\(10^{24}\) |
|
\(10^{21}\) |
|
\(10^{18}\) |
|
\(10^{15}\) |
|
\(10^{12}\) |
|
\(10^{9}\) |
|
\(10^{6}\) |
|
\(10^{3}\) |
|
\(10^{2}\) |
|
\(10^{1}\) |
|
\(10^{-1}\) |
|
\(10^{-2}\) |
|
\(10^{-3}\) |
|
\(10^{-6}\) |
|
\(10^{-9}\) |
|
\(10^{-12}\) |
|
\(10^{-15}\) |
|
\(10^{-18}\) |
|
\(10^{-21}\) |
Binary prefixes¶
|
\(2^{10}\) |
|
\(2^{20}\) |
|
\(2^{30}\) |
|
\(2^{40}\) |
|
\(2^{50}\) |
|
\(2^{60}\) |
|
\(2^{70}\) |
|
\(2^{80}\) |
Mass¶
|
\(10^{-3}\) kg |
|
\(10^{3}\) kg |
|
one grain in kg |
|
one pound (avoirdupous) in kg |
|
one pound (avoirdupous) in kg |
|
one inch version of a slug in kg (added in 1.0.0) |
|
one inch version of a slug in kg (added in 1.0.0) |
|
one slug in kg (added in 1.0.0) |
|
one ounce in kg |
|
one ounce in kg |
|
one stone in kg |
|
one grain in kg |
|
one long ton in kg |
|
one short ton in kg |
|
one Troy ounce in kg |
|
one Troy pound in kg |
|
one carat in kg |
|
atomic mass constant (in kg) |
|
atomic mass constant (in kg) |
|
atomic mass constant (in kg) |
Angle¶
|
degree in radians |
|
arc minute in radians |
|
arc minute in radians |
|
arc second in radians |
|
arc second in radians |
Time¶
|
one minute in seconds |
|
one hour in seconds |
|
one day in seconds |
|
one week in seconds |
|
one year (365 days) in seconds |
|
one Julian year (365.25 days) in seconds |
Length¶
|
one inch in meters |
|
one foot in meters |
|
one yard in meters |
|
one mile in meters |
|
one mil in meters |
|
one point in meters |
|
one point in meters |
|
one survey foot in meters |
|
one survey mile in meters |
|
one nautical mile in meters |
|
one Fermi in meters |
|
one Angstrom in meters |
|
one micron in meters |
|
one astronomical unit in meters |
|
one astronomical unit in meters |
|
one light year in meters |
|
one parsec in meters |
Pressure¶
|
standard atmosphere in pascals |
|
standard atmosphere in pascals |
|
one bar in pascals |
|
one torr (mmHg) in pascals |
|
one torr (mmHg) in pascals |
|
one psi in pascals |
Area¶
|
one hectare in square meters |
|
one acre in square meters |
Volume¶
|
one liter in cubic meters |
|
one liter in cubic meters |
|
one gallon (US) in cubic meters |
|
one gallon (US) in cubic meters |
|
one gallon (UK) in cubic meters |
|
one fluid ounce (US) in cubic meters |
|
one fluid ounce (US) in cubic meters |
|
one fluid ounce (UK) in cubic meters |
|
one barrel in cubic meters |
|
one barrel in cubic meters |
Speed¶
|
kilometers per hour in meters per second |
|
miles per hour in meters per second |
|
one Mach (approx., at 15 C, 1 atm) in meters per second |
|
one Mach (approx., at 15 C, 1 atm) in meters per second |
|
one knot in meters per second |
Temperature¶
|
zero of Celsius scale in Kelvin |
|
one Fahrenheit (only differences) in Kelvins |
|
Convert from a temperature scale to another one among Celsius, Kelvin, Fahrenheit, and Rankine scales. |
Energy¶
|
one electron volt in Joules |
|
one electron volt in Joules |
|
one calorie (thermochemical) in Joules |
|
one calorie (thermochemical) in Joules |
|
one calorie (International Steam Table calorie, 1956) in Joules |
|
one erg in Joules |
|
one British thermal unit (International Steam Table) in Joules |
|
one British thermal unit (International Steam Table) in Joules |
|
one British thermal unit (thermochemical) in Joules |
|
one ton of TNT in Joules |
Power¶
|
one horsepower in watts |
|
one horsepower in watts |
Force¶
|
one dyne in newtons |
|
one dyne in newtons |
|
one pound force in newtons |
|
one pound force in newtons |
|
one kilogram force in newtons |
|
one kilogram force in newtons |
References¶
- CODATA2018
CODATA Recommended Values of the Fundamental Physical Constants 2018.