问题
Just curious - is there a package or dataset somewhere containing values for physical constants? I only ask because I've now typed in 273.15 (Celsius to Kelvin conversion) wrong several times. =)
回答1:
The packages marelac and dielectric both have some physical constants, but not that one in particular. marelac::convert_T will do the temperature conversions.
回答2:
It's a fairly large task to assemble this information but some of the thermodynamic constants are available in marelac:
> convert_T(0, "K")
K C F
1 0 -273.15 -459.67
In addition to the R resources in my answer to the question that that @joran cited these are further resources at NIST:
http://www.nist.gov/pml/wmd/metric/si-units.cfm
http://www.nist.gov/pml/wmd/pubs/upload/AppC-11-hb44-final.pdf
http://www.nist.gov/pml/wmd/pubs/upload/AppC-11-hb44-final.pdf
I took on the task of reading the NIST Constants Table, editing it so the conversion to numeric would be reasonable, and this was the input code:
require(foreign)
fundconst <- read.fwf("allascii.txt",
widths=diff(c(0,54, 77, 99, 111)),
header=FALSE, skip=12)
fundconst$V1 <- gsub(" ", "", fundconst[,1]) # strips some of hte white-space
fundconst$V2 <- as.numeric(gsub(" ", "", fundconst[,2]))
fundconst$V3 <- as.numeric(gsub(" ", "", fundconst[,3]))
names(fundconst) <- c("Quantity", "Value", "Uncertainty", "Unit")
dput(fundconst)
.... and here is the dput version:
fundconst <-
structure(list(Quantity = c("alpha particle-electron mass ratio",
"alpha particle mass ", "alpha particle mass energy equivalent ",
"alpha particle mass energy equivalent in MeV", "alpha particle mass in u",
"alpha particle molar mass ", "alpha particle-proton mass ratio",
"Angstrom star ", "atomic mass constant", "atomic mass constant energy equivalent",
"atomic mass constant energy equivalent in MeV ", "atomic mass unit-electron volt relationship ",
"atomic mass unit-hartree relationship ", "atomic mass unit-hertz relationship ",
"atomic mass unit-inverse meter relationship ", "atomic mass unit-joule relationship ",
"atomic mass unit-kelvin relationship", "atomic mass unit-kilogram relationship",
"atomic unit of 1st hyperpolarizability", "atomic unit of 2nd hyperpolarizability",
"atomic unit of action ", "atomic unit of charge ", "atomic unit of charge density ",
"atomic unit of current", "atomic unit of electric dipole mom. ",
"atomic unit of electric field ", "atomic unit of electric field gradient",
"atomic unit of electric polarizability", "atomic unit of electric potential ",
"atomic unit of electric quadrupole mom. ", "atomic unit of energy ",
"atomic unit of force", "atomic unit of length ", "atomic unit of mag. dipole mom. ",
"atomic unit of mag. flux density", "atomic unit of magnetizability",
"atomic unit of mass ", "atomic unit of mom.um ", "atomic unit of permittivity ",
"atomic unit of time ", "atomic unit of velocity ", "Avogadro constant ",
"Bohr magneton ", "Bohr magneton in eV/T ", "Bohr magneton in Hz/T ",
"Bohr magneton in inverse meters per tesla ", "Bohr magneton in K/T",
"Bohr radius ", "Boltzmann constant", "Boltzmann constant in eV/K",
"Boltzmann constant in Hz/K", "Boltzmann constant in inverse meters per kelvin ",
"characteristic impedance of vacuum", "classical electron radius ",
"Compton wavelength", "Compton wavelength over 2 pi", "conductance quantum ",
"conventional value of Josephson constant", "conventional value of von Klitzing constant ",
"Cu x unit ", "deuteron-electron mag. mom. ratio ", "deuteron-electron mass ratio",
"deuteron g factor ", "deuteron mag. mom.", "deuteron mag. mom. to Bohr magneton ratio ",
"deuteron mag. mom. to nuclear magneton ratio", "deuteron mass ",
"deuteron mass energy equivalent ", "deuteron mass energy equivalent in MeV",
"deuteron mass in u", "deuteron molar mass ", "deuteron-neutron mag. mom. ratio",
"deuteron-proton mag. mom. ratio ", "deuteron-proton mass ratio",
"deuteron rms charge radius", "electric constant ", "electron charge to mass quotient",
"electron-deuteron mag. mom. ratio ", "electron-deuteron mass ratio",
"electron g factor ", "electron gyromag. ratio ", "electron gyromag. ratio over 2 pi ",
"electron-helion mass ratio", "electron mag. mom.", "electron mag. mom. anomaly",
"electron mag. mom. to Bohr magneton ratio ", "electron mag. mom. to nuclear magneton ratio",
"electron mass ", "electron mass energy equivalent ", "electron mass energy equivalent in MeV",
"electron mass in u", "electron molar mass ", "electron-muon mag. mom. ratio ",
"electron-muon mass ratio", "electron-neutron mag. mom. ratio",
"electron-neutron mass ratio ", "electron-proton mag. mom. ratio ",
"electron-proton mass ratio", "electron-tau mass ratio ", "electron to alpha particle mass ratio ",
"electron to shielded helion mag. mom. ratio ", "electron to shielded proton mag. mom. ratio ",
"electron-triton mass ratio", "electron volt ", "electron volt-atomic mass unit relationship ",
"electron volt-hartree relationship", "electron volt-hertz relationship",
"electron volt-inverse meter relationship", "electron volt-joule relationship",
"electron volt-kelvin relationship ", "electron volt-kilogram relationship ",
"elementary charge ", "elementary charge over h", "Faraday constant",
"Faraday constant for conventional electric current", "Fermi coupling constant ",
"fine-structure constant ", "first radiation constant", "first radiation constant for spectral radiance",
"hartree-atomic mass unit relationship ", "hartree-electron volt relationship",
"Hartree energy", "Hartree energy in eV", "hartree-hertz relationship",
"hartree-inverse meter relationship", "hartree-joule relationship",
"hartree-kelvin relationship ", "hartree-kilogram relationship ",
"helion-electron mass ratio", "helion g factor ", "helion mag. mom.",
"helion mag. mom. to Bohr magneton ratio ", "helion mag. mom. to nuclear magneton ratio",
"helion mass ", "helion mass energy equivalent ", "helion mass energy equivalent in MeV",
"helion mass in u", "helion molar mass ", "helion-proton mass ratio",
"hertz-atomic mass unit relationship ", "hertz-electron volt relationship",
"hertz-hartree relationship", "hertz-inverse meter relationship",
"hertz-joule relationship", "hertz-kelvin relationship ", "hertz-kilogram relationship ",
"inverse fine-structure constant ", "inverse meter-atomic mass unit relationship ",
"inverse meter-electron volt relationship", "inverse meter-hartree relationship",
"inverse meter-hertz relationship", "inverse meter-joule relationship",
"inverse meter-kelvin relationship ", "inverse meter-kilogram relationship ",
"inverse of conductance quantum", "Josephson constant", "joule-atomic mass unit relationship ",
"joule-electron volt relationship", "joule-hartree relationship",
"joule-hertz relationship", "joule-inverse meter relationship",
"joule-kelvin relationship ", "joule-kilogram relationship ",
"kelvin-atomic mass unit relationship", "kelvin-electron volt relationship ",
"kelvin-hartree relationship ", "kelvin-hertz relationship ",
"kelvin-inverse meter relationship ", "kelvin-joule relationship ",
"kelvin-kilogram relationship", "kilogram-atomic mass unit relationship",
"kilogram-electron volt relationship ", "kilogram-hartree relationship ",
"kilogram-hertz relationship ", "kilogram-inverse meter relationship ",
"kilogram-joule relationship ", "kilogram-kelvin relationship",
"lattice parameter of silicon", "Loschmidt constant (273.15 K, 100 kPa)",
"Loschmidt constant (273.15 K, 101.325 kPa)", "mag. constant ",
"mag. flux quantum ", "molar gas constant", "molar mass constant ",
"molar mass of carbon-12 ", "molar Planck constant ", "molar Planck constant times c ",
"molar volume of ideal gas (273.15 K, 100 kPa) ", "molar volume of ideal gas (273.15 K, 101.325 kPa) ",
"molar volume of silicon ", "Mo x unit ", "muon Compton wavelength ",
"muon Compton wavelength over 2 pi ", "muon-electron mass ratio",
"muon g factor ", "muon mag. mom.", "muon mag. mom. anomaly",
"muon mag. mom. to Bohr magneton ratio ", "muon mag. mom. to nuclear magneton ratio",
"muon mass ", "muon mass energy equivalent ", "muon mass energy equivalent in MeV",
"muon mass in u", "muon molar mass ", "muon-neutron mass ratio ",
"muon-proton mag. mom. ratio ", "muon-proton mass ratio", "muon-tau mass ratio ",
"natural unit of action", "natural unit of action in eV s", "natural unit of energy",
"natural unit of energy in MeV ", "natural unit of length", "natural unit of mass",
"natural unit of mom.um", "natural unit of mom.um in MeV/c ",
"natural unit of time", "natural unit of velocity", "neutron Compton wavelength",
"neutron Compton wavelength over 2 pi", "neutron-electron mag. mom. ratio",
"neutron-electron mass ratio ", "neutron g factor", "neutron gyromag. ratio",
"neutron gyromag. ratio over 2 pi", "neutron mag. mom. ", "neutron mag. mom. to Bohr magneton ratio",
"neutron mag. mom. to nuclear magneton ratio ", "neutron mass",
"neutron mass energy equivalent", "neutron mass energy equivalent in MeV ",
"neutron mass in u ", "neutron molar mass", "neutron-muon mass ratio ",
"neutron-proton mag. mom. ratio", "neutron-proton mass difference",
"neutron-proton mass difference energy equivalent", "neutron-proton mass difference energy equivalent MeV",
"neutron-proton mass difference in u ", "neutron-proton mass ratio ",
"neutron-tau mass ratio", "neutron to shielded proton mag. mom. ratio",
"Newtonian constant of gravitation ", "Newtonian constant of gravitation over h-bar c",
"nuclear magneton", "nuclear magneton in eV/T", "nuclear magneton in inverse meters per tesla",
"nuclear magneton in K/T ", "nuclear magneton in MHz/T ", "Planck constant ",
"Planck constant in eV s ", "Planck constant over 2 pi ", "Planck constant over 2 pi in eV s ",
"Planck constant over 2 pi times c in MeV fm ", "Planck length ",
"Planck mass ", "Planck mass energy equivalent in GeV", "Planck temperature",
"Planck time ", "proton charge to mass quotient", "proton Compton wavelength ",
"proton Compton wavelength over 2 pi ", "proton-electron mass ratio",
"proton g factor ", "proton gyromag. ratio ", "proton gyromag. ratio over 2 pi ",
"proton mag. mom.", "proton mag. mom. to Bohr magneton ratio ",
"proton mag. mom. to nuclear magneton ratio", "proton mag. shielding correction",
"proton mass ", "proton mass energy equivalent ", "proton mass energy equivalent in MeV",
"proton mass in u", "proton molar mass ", "proton-muon mass ratio",
"proton-neutron mag. mom. ratio", "proton-neutron mass ratio ",
"proton rms charge radius", "proton-tau mass ratio ", "quantum of circulation",
"quantum of circulation times 2", "Rydberg constant", "Rydberg constant times c in Hz",
"Rydberg constant times hc in eV ", "Rydberg constant times hc in J",
"Sackur-Tetrode constant (1 K, 100 kPa)", "Sackur-Tetrode constant (1 K, 101.325 kPa)",
"second radiation constant ", "shielded helion gyromag. ratio",
"shielded helion gyromag. ratio over 2 pi", "shielded helion mag. mom. ",
"shielded helion mag. mom. to Bohr magneton ratio", "shielded helion mag. mom. to nuclear magneton ratio ",
"shielded helion to proton mag. mom. ratio ", "shielded helion to shielded proton mag. mom. ratio",
"shielded proton gyromag. ratio", "shielded proton gyromag. ratio over 2 pi",
"shielded proton mag. mom. ", "shielded proton mag. mom. to Bohr magneton ratio",
"shielded proton mag. mom. to nuclear magneton ratio ", "speed of light in vacuum",
"standard acceleration of gravity", "standard atmosphere ", "standard-state pressure ",
"Stefan-Boltzmann constant ", "tau Compton wavelength", "tau Compton wavelength over 2 pi",
"tau-electron mass ratio ", "tau mass", "tau mass energy equivalent",
"tau mass energy equivalent in MeV ", "tau mass in u ", "tau molar mass",
"tau-muon mass ratio ", "tau-neutron mass ratio", "tau-proton mass ratio ",
"Thomson cross section ", "triton-electron mass ratio", "triton g factor ",
"triton mag. mom.", "triton mag. mom. to Bohr magneton ratio ",
"triton mag. mom. to nuclear magneton ratio", "triton mass ",
"triton mass energy equivalent ", "triton mass energy equivalent in MeV",
"triton mass in u", "triton molar mass ", "triton-proton mass ratio",
"unified atomic mass unit", "von Klitzing constant ", "weak mixing angle ",
"Wien frequency displacement law constant", "Wien wavelength displacement law constant "
), Value = c(7294.2995361, 6.64465675e-27, 5.97191967e-10, 3727.37924,
4.001506179125, 0.004001506179125, 3.97259968933, 1.00001495e-10,
1.660538921e-27, 1.492417954e-10, 931.494061, 931494061, 34231776.845,
2.2523427168e+23, 751300660420000, 1.492417954e-10, 10809540800000,
1.660538921e-27, 3.206361449e-53, 6.23538054e-65, 1.054571726e-34,
1.602176565e-19, 1081202338000, 0.00662361795, 8.47835326e-30,
514220652000, 9.717362e+21, 1.6487772754e-41, 27.21138505, 4.486551331e-40,
4.35974434e-18, 8.23872278e-08, 5.2917721092e-11, 1.854801936e-23,
235051.7464, 7.891036607e-29, 9.10938291e-31, 1.99285174e-24,
1.112650056e-10, 2.418884326502e-17, 2187691.26379, 6.02214129e+23,
9.27400968e-24, 5.7883818066e-05, 13996245550, 46.6864498, 0.67171388,
5.2917721092e-11, 1.3806488e-23, 8.6173324e-05, 20836618000,
69.503476, 376.730313461, 2.8179403267e-15, 2.4263102389e-12,
3.86159268e-13, 7.7480917346e-05, 4.835979e+14, 25812.807, 1.00207697e-13,
-0.0004664345537, 3670.4829652, 0.8574382308, 4.33073489e-27,
0.0004669754556, 0.8574382308, 3.34358348e-27, 3.00506297e-10,
1875.612859, 2.013553212712, 0.002013553212712, -0.44820652,
0.307012207, 1.99900750097, 2.1424e-15, 8.854187817e-12, -175882008800,
-2143.923498, 0.00027244371095, -2.00231930436153, 176085970800,
28024.95266, 0.00018195430761, -9.2847643e-24, 0.00115965218076,
-1.00115965218076, -1838.2819709, 9.10938291e-31, 8.18710506e-14,
0.510998928, 0.00054857990946, 5.4857990946e-07, 206.7669896,
0.00483633166, 960.9205, 0.00054386734461, -658.2106848, 0.00054461702178,
0.000287592, 0.000137093355578, 864.058257, -658.2275971, 0.00018192000653,
1.602176565e-19, 1.07354415e-09, 0.03674932379, 241798934800000,
806554.429, 1.602176565e-19, 11604.519, 1.782661845e-36, 1.602176565e-19,
241798934800000, 96485.3365, 96485.3321, 1.166364e-05, 0.0072973525698,
3.74177153e-16, 1.191042869e-16, 2.9212623246e-08, 27.21138505,
4.35974434e-18, 27.21138505, 6579683920729000, 21947463.13708,
4.35974434e-18, 315775.04, 4.85086979e-35, 5495.8852754, -4.255250613,
-1.074617486e-26, -0.001158740958, -2.127625306, 5.00641234e-27,
4.49953902e-10, 2808.391482, 3.0149322468, 0.0030149322468, 2.9931526707,
4.4398216689e-24, 4.135667516e-15, 1.5198298460045e-16, 3.335640951e-09,
6.62606957e-34, 4.7992434e-11, 7.37249668e-51, 137.035999074,
1.3310250512e-15, 1.23984193e-06, 4.556335252755e-08, 299792458,
1.986445684e-25, 0.01438777, 2.210218902e-42, 12906.4037217,
4.8359787e+14, 6700535850, 6.24150934e+18, 2.29371248e+17, 1.509190311e+33,
5.03411701e+24, 7.2429716e+22, 1.112650056e-17, 9.2510868e-14,
8.6173324e-05, 3.1668114e-06, 20836618000, 69.503476, 1.3806488e-23,
1.536179e-40, 6.02214129e+26, 5.60958885e+35, 2.061485968e+34,
1.356392608e+50, 4.52443873e+41, 8.987551787e+16, 6.5096582e+39,
5.431020504e-10, 2.6516462e+25, 2.6867805e+25, 1.2566370614e-06,
2.067833758e-15, 8.3144621, 0.001, 0.012, 3.9903127176e-10, 0.119626565779,
0.022710953, 0.022413968, 1.205883301e-05, 1.00209952e-13, 1.173444103e-14,
1.867594294e-15, 206.7682843, -2.0023318418, -4.49044807e-26,
0.00116592091, -0.00484197044, -8.89059697, 1.883531475e-28,
1.692833667e-11, 105.6583715, 0.1134289267, 0.0001134289267,
0.1124545177, -3.183345107, 0.1126095272, 0.0594649, 1.054571726e-34,
6.58211928e-16, 8.18710506e-14, 0.510998928, 3.86159268e-13,
9.10938291e-31, 2.73092429e-22, 0.510998928, 1.28808866833e-21,
299792458, 1.3195909068e-15, 2.1001941568e-16, 0.00104066882,
1838.6836605, -3.82608545, 183247179, 29.1646943, -9.6623647e-27,
-0.00104187563, -1.91304272, 1.674927351e-27, 1.505349631e-10,
939.565379, 1.008664916, 0.001008664916, 8.892484, -0.68497934,
2.30557392e-30, 2.0721465e-13, 1.29333217, 0.00138844919, 1.00137841917,
0.52879, -0.68499694, 6.67384e-11, 6.70837e-39, 5.05078353e-27,
3.1524512605e-08, 0.02542623527, 0.00036582682, 7.62259357, 6.62606957e-34,
4.135667516e-15, 1.054571726e-34, 6.58211928e-16, 197.3269718,
1.616199e-35, 2.17651e-08, 1.220932e+19, 1.416833e+32, 5.39106e-44,
95788335.8, 1.32140985623e-15, 2.1030891047e-16, 1836.15267245,
5.585694713, 267522200.5, 42.5774806, 1.410606743e-26, 0.00152103221,
2.792847356, 2.5694e-05, 1.672621777e-27, 1.503277484e-10, 938.272046,
1.007276466812, 0.001007276466812, 8.88024331, -1.45989806, 0.99862347826,
8.775e-16, 0.528063, 0.0003636947552, 0.0007273895104, 10973731.568539,
3289841960364000, 13.60569253, 2.179872171e-18, -1.1517078, -1.1648708,
0.01438777, 203789465.9, 32.43410084, -1.074553044e-26, -0.001158671471,
-2.127497718, -0.761766558, -0.7617861313, 267515326.8, 42.5763866,
1.410570499e-26, 0.001520993128, 2.792775598, 299792458, 9.80665,
101325, 1e+05, 5.670373e-08, 6.97787e-16, 1.11056e-16, 3477.15,
3.16747e-27, 2.84678e-10, 1776.82, 1.90749, 0.00190749, 16.8167,
1.89111, 1.89372, 6.652458734e-29, 5496.9215267, 5.957924896,
1.504609447e-26, 0.001622393657, 2.978962448, 5.0073563e-27,
4.50038741e-10, 2808.921005, 3.0155007134, 0.0030155007134, 2.9937170308,
1.660538921e-27, 25812.8074434, 0.2223, 58789254000, 0.0028977721
), Uncertainty = c(2.9e-06, 2.9e-34, 2.6e-17, 8.2e-05, 6.2e-11,
6.2e-14, 3.6e-10, 9e-17, 7.3e-35, 6.6e-18, 2.1e-05, 21, 0.024,
1.6e+14, 530000, 6.6e-18, 9800000, 7.3e-35, 7.1e-61, 2.8e-72,
4.7e-42, 3.5e-27, 24000, 1.5e-10, 1.9e-37, 11000, 2.1e+14, 1.6e-50,
6e-07, 9.9e-48, 1.9e-25, 3.6e-15, 1.7e-20, 4.1e-31, 0.0052, 1.3e-37,
4e-38, 8.8e-32, NA, 1.2e-28, 0.00071, 2.7e+16, 2e-31, 3.8e-14,
310, 1e-06, 6.1e-07, 1.7e-20, 1.3e-29, 7.8e-11, 19000, 6.3e-05,
NA, 2.7e-24, 1.6e-21, 2.5e-22, 2.5e-14, NA, NA, 2.8e-20, 3.9e-12,
1.5e-06, 7.2e-09, 1e-34, 3.9e-12, 7.2e-09, 1.5e-34, 1.3e-17,
4.1e-05, 7.7e-11, 7.7e-14, 1.1e-07, 2.4e-09, 1.8e-10, 2.1e-18,
NA, 3900, 1.8e-05, 1.1e-13, 5.3e-13, 3900, 0.00062, 1.7e-13,
2.1e-31, 2.7e-13, 2.7e-13, 7.5e-07, 4e-38, 3.6e-21, 1.1e-08,
2.2e-13, 2.2e-16, 5.2e-06, 1.2e-10, 0.00023, 3.2e-13, 5.4e-06,
2.2e-13, 2.6e-08, 5.5e-14, 1e-05, 7.2e-06, 1.7e-13, 3.5e-27,
2.4e-17, 8.1e-10, 5300000, 0.018, 3.5e-27, 0.011, 3.9e-44, 3.5e-27,
5300000, 0.0021, 0.0043, 5e-11, 2.4e-12, 1.7e-23, 5.3e-24, 2.1e-17,
6e-07, 1.9e-25, 6e-07, 33000, 0.00011, 1.9e-25, 0.29, 2.1e-42,
5e-06, 5e-08, 2.7e-34, 1.4e-11, 2.5e-08, 2.2e-34, 2e-17, 6.2e-05,
2.5e-09, 2.5e-12, 2.5e-09, 3.1e-33, 9.1e-23, 7.6e-12, NA, 2.9e-41,
4.4e-17, 3.3e-58, 4.4e-08, 9.4e-25, 2.7e-14, 2.3e-19, NA, 8.8e-33,
1.3e-08, 9.8e-50, 4.2e-06, 1.1e+07, 300, 1.4e+11, 1e+10, 6.7e+25,
2.2e+17, 6.6e+16, NA, 8.4e-20, 7.8e-11, 2.9e-12, 19000, 6.3e-05,
1.3e-29, 1.4e-46, 2.7e+19, 1.2e+28, 9.1e+26, 6e+42, 2e+34, NA,
5.9e+33, 8.9e-18, 2.4e+19, 2.4e+19, NA, 4.6e-23, 7.5e-06, NA,
NA, 2.8e-19, 8.4e-11, 2.1e-08, 2e-08, 8e-13, 5.3e-20, 3e-22,
4.7e-23, 5.2e-06, 1.3e-09, 1.5e-33, 6.3e-10, 1.2e-10, 2.2e-07,
9.6e-36, 8.6e-19, 3.5e-06, 2.9e-09, 2.9e-12, 2.8e-09, 8.4e-08,
2.8e-09, 5.4e-06, 4.7e-42, 1.5e-23, 3.6e-21, 1.1e-08, 2.5e-22,
4e-38, 1.2e-29, 1.1e-08, 8.3e-31, NA, 1.1e-24, 1.7e-25, 2.5e-10,
1.1e-06, 9e-07, 43, 6.9e-06, 2.3e-33, 2.5e-10, 4.5e-07, 7.4e-35,
6.6e-18, 2.1e-05, 4.3e-10, 4.3e-13, 2.2e-07, 1.6e-07, 7.6e-37,
6.8e-20, 4.2e-07, 4.5e-10, 4.5e-10, 4.8e-05, 1.6e-07, 8e-15,
8e-43, 1.1e-34, 2.2e-17, 5.6e-10, 3.3e-10, 1.7e-07, 2.9e-41,
9.1e-23, 4.7e-42, 1.5e-23, 4.4e-06, 9.7e-40, 1.3e-12, 7.3e+14,
8.5e+27, 3.2e-48, 2.1, 9.4e-25, 1.5e-25, 7.5e-07, 4.6e-08, 6.3,
1e-06, 3.3e-34, 1.2e-11, 2.3e-08, 1.4e-08, 7.4e-35, 6.6e-18,
2.1e-05, 9e-11, 9e-14, 2.2e-07, 3.4e-07, 4.5e-10, 5.1e-18, 4.8e-05,
2.4e-13, 4.7e-13, 5.5e-05, 17000, 3e-07, 9.6e-26, 2.3e-06, 2.3e-06,
1.3e-08, 5.1, 8.1e-07, 2.7e-34, 1.4e-11, 2.5e-08, 1.1e-08, 3.3e-09,
6.6, 1e-06, 3.5e-34, 1.7e-11, 3e-08, NA, NA, NA, NA, 2.1e-13,
6.3e-20, 1e-20, 0.31, 2.9e-31, 2.6e-14, 0.16, 0.00017, 1.7e-07,
0.0015, 0.00017, 0.00017, 1.3e-37, 5e-06, 7.6e-08, 3.8e-34, 2.1e-11,
3.8e-08, 2.2e-34, 2e-17, 6.2e-05, 2.5e-09, 2.5e-12, 2.5e-09,
7.3e-35, 8.4e-06, 0.0021, 53000, 2.6e-09), Unit = structure(c(NA,
38L, 28L, 53L, 66L, 40L, NA, 41L, 38L, 28L, 53L, 17L, 16L, 24L,
45L, 28L, 36L, 38L, 13L, 14L, 32L, 6L, 9L, 4L, 8L, 68L, 69L,
12L, 67L, 10L, 28L, 58L, 41L, 34L, 65L, 35L, 38L, 39L, 21L, 1L,
43L, 57L, 34L, 20L, 26L, 47L, 37L, 41L, 29L, 18L, 25L, 46L, 60L,
41L, 41L, 41L, 63L, 27L, 60L, 41L, NA, NA, NA, 34L, NA, NA, 38L,
28L, 53L, 66L, 40L, NA, NA, NA, 41L, 21L, 7L, NA, NA, NA, 64L,
56L, NA, 34L, NA, NA, NA, 38L, 28L, 53L, 66L, 40L, NA, NA, NA,
NA, NA, NA, NA, NA, NA, NA, NA, 28L, 66L, 16L, 24L, 45L, 28L,
36L, 38L, 6L, 5L, 11L, 15L, 23L, NA, 71L, 72L, 66L, 17L, 28L,
17L, 24L, 45L, 28L, 36L, 38L, NA, NA, 34L, NA, NA, 38L, 28L,
53L, 66L, 40L, NA, 66L, 17L, 3L, 45L, 28L, 36L, 38L, NA, 66L,
17L, 16L, 24L, 28L, 36L, 38L, 60L, 27L, 66L, 17L, 16L, 24L, 45L,
36L, 38L, 66L, 17L, 16L, 24L, 45L, 28L, 38L, 66L, 17L, 16L, 24L,
45L, 28L, 36L, 41L, 48L, 48L, 59L, 73L, 31L, 40L, 40L, 33L, 30L,
52L, 52L, 52L, 41L, 41L, 41L, NA, NA, 34L, NA, NA, NA, 38L, 28L,
53L, 66L, 40L, NA, NA, NA, NA, 32L, 19L, 28L, 53L, 41L, 38L,
39L, 55L, 62L, 43L, 41L, 41L, NA, NA, NA, 64L, 56L, 34L, NA,
NA, 38L, 28L, 53L, 66L, 40L, NA, NA, NA, NA, NA, NA, NA, NA,
NA, 51L, 2L, 34L, 20L, 47L, 37L, 56L, 32L, 19L, 32L, 19L, 54L,
41L, 38L, 22L, 36L, 62L, 7L, 41L, 41L, NA, NA, 64L, 56L, 34L,
NA, NA, NA, 38L, 28L, 53L, 66L, 40L, NA, NA, NA, 41L, NA, 50L,
50L, 45L, 24L, 17L, 28L, NA, NA, 42L, 64L, 56L, 34L, NA, NA,
NA, NA, 64L, 56L, 34L, NA, NA, 43L, 44L, 61L, 61L, 70L, 41L,
41L, NA, 38L, 28L, 53L, 66L, 40L, NA, NA, NA, 49L, NA, NA, 34L,
NA, NA, 38L, 28L, 53L, 66L, 40L, NA, 38L, 60L, NA, 25L, 42L), .Label = c(" s",
"(GeV/c^2)^-2", "16 E_h", "A", "A J^-1", "C", "C kg^-1", "C m",
"C m^-3", "C m^2", "C mol^-1", "C^2 m^2 J^-1", "C^3 m^3 J^-2",
"C^4 m^4 J^-3", "C_90 mol^-1", "E_h", "eV", "eV K^-1", "eV s",
"eV T^-1", "F m^-1", "GeV", "GeV^-2", "Hz", "Hz K^-1", "Hz T^-1",
"Hz V^-1", "J", "J K^-1", "J m mol^-1", "J mol^-1 K^-", "J s",
"J s mol^-1", "J T^-1", "J T^-2", "K", "K T^-1", "kg", "kg m s^-1",
"kg mol^-1", "m", "m K", "m s^-1", "m s^-2", "m^-1", "m^-1 K^-1",
"m^-1 T^-1", "m^-3", "m^2", "m^2 s^-1", "m^3 kg^-1 s^", "m^3 mol^-1",
"MeV", "MeV fm", "MeV/c", "MHz T^-1", "mol^-1", "N", "N A^-2",
"ohm", "Pa", "s", "S", "s^-1 T^-1", "T", "u", "V", "V m^-1",
"V m^-2", "W m^-2 K^-4", "W m^2", "W m^2 sr^-1", "Wb"), class = "factor")), .Names = c("Quantity",
"Value", "Uncertainty", "Unit"), row.names = c(NA, -334L), class = "data.frame")
回答3:
May I recommend 2 options:
1) If you need these constants all the time you could make use of the .First library in the form of C2K<-273.15. You can assign constants and store them there. For more on this see http://cran.r-project.org/doc/contrib/Lemon-kickstart/kr_first.html
2) If you want to use the files only sometimes save the constants in a text file in the same format as above x<-273.15 and then source the path to this file using the source function in the following format:
source(C:\Users\PAth to save file text\formulas.txt)
This gives you more control over the constants than relying on a package that may or may not contain what you want.
回答4:
Should be fairly easy to download and parse this:
http://physics.nist.gov/cuu/Constants/Table/allascii.txt
- looks like fixed format, but those numeric triples might be a bit fiddly. It doesn't have your 273.15 though, because maybe its not a "physical constant" by some definition. But if you ever need the shielded helion to shielded proton mag. mom. ratio, its there.
[actually scratch that, that file is not nicely formatted, and a couple of the constants break even the approximate fixed-width formatting. Needs cleverer processing to be useful]
回答5:
Here is another parsing of the NIST CODATA table of physical constants. It is similar to BondedDust's answer above but with (what I think is) slightly easier readability due to use of stringr.
#parsing NIST CODATA data for physical constants
require(stringr) #simplifies regex usage syntax in R
#web page with data
link <- 'http://physics.nist.gov/cuu/Constants/Table/allascii.txt'
allstr <- readLines(link)
codata.str <- allstr[11:345] #data starts at line 11
#at least 3 spaces separate columns
codata.str2 <- str_replace_all(codata.str, '[ ]{3,100}', '\t')
#four cols in source table
codata.mat <- str_split_fixed(codata.str2, '\t', n=4)
#eliminate spaces separating every three decimal digits
codata.mat[,c(2,3)] <- str_replace_all(codata.mat[,c(2,3)], " ", "")
codata <- data.frame(quantity = codata.mat[,1],
value = as.numeric(codata.mat[,2]),
uncertainty = as.numeric(codata.mat[,3]),
units = codata.mat[,4]
)
And that's it. Now it's easy to search — in R — the data to find the constants you want, and assign constants that you will use to variable names, without having to manually type them.
> codata[str_detect(codata$quantity, 'electron mass'),]
quantity value uncertainty units
2 alpha particle-electron mass ratio 7.294300e+03 2.9e-06
63 deuteron-electron mass ratio 3.670483e+03 1.5e-06
89 electron mass 9.109383e-31 4.0e-38 kg
90 electron mass energy equivalent 8.187105e-14 3.6e-21 J
91 electron mass energy equivalent in MeV 5.109989e-01 1.1e-08 MeV
92 electron mass in u 5.485799e-04 2.2e-13 u
130 helion-electron mass ratio 5.495885e+03 5.0e-06
195 muon-electron mass ratio 2.067683e+02 5.2e-06
223 neutron-electron mass ratio 1.838684e+03 1.1e-06
264 proton-electron mass ratio 1.836153e+03 7.5e-07
310 tau-electron mass ratio 3.477150e+03 3.1e-01
320 triton-electron mass ratio 5.496922e+03 5.0e-06
> me.u < codata[str_detect(codata$quantity, 'electron mass in u'),'value']
> me.u
[1] 0.0005485799
来源：https://stackoverflow.com/questions/8087407/physical-constants-in-r