Units`
As of Version 9, the new units framework can be used via Quantity in place of the Units` package.
The Units` package provided a selection of commonly used units found in various scientific fields. The units framework provided by Quantity replaces these completely.
All the previous units are given as fundamental units in the new system, which are represented as strings inside Quantity expressions. Functions such as Convert, ConvertTemperature, and SI have been integrated into UnitConvert, which can take either a target unit or target unit system.
Conversion Functions
Units` | Version 9 |
Convert[expr, newunits] | UnitConvert[quantity, newunits] |
ConvertTemperature[expr, newunits] | UnitConvert[quantity, newunits] |
SI[expr] | UnitConvert[quantity, "SI"] |
SI Prefixes
SI prefixes such as kilo, micro, and yotta have been integrated into the applicable SI units to form distinct unit names, such as "kilometers" and "yottaseconds".
Quantity and Units
Quantity uses canonical unit names, most of which are the plural forms of the old unit names, but also includes the ability to interpret unknown unit names automatically.
There are equivalents for all units included in the Units` package, and many more beyond that.
Length Units
Units` | Version 9 |
Angstrom | Quantity["Angstroms"] |
AU | Quantity["AstronomicalUnit"] |
AstronomicalUnit | Quantity["AstronomicalUnit"] |
Bolt | Quantity["BoltsLength"] |
Cable | Quantity["CableLengthsUSNavy"] |
Caliber | Quantity["Calibres"] |
Centimeter | Quantity["Centimeters"] |
Chain | Quantity["GuntersChains"] |
Cicero | Quantity["Ciceros"] |
Cubit | Quantity["Cubits"] |
Didot | Quantity["DidotPoints"] |
DidotPoint | Quantity["DidotPoints"] |
Diopter | Quantity["Diopters"] |
Ell | Quantity["Ells"] |
Fathom | Quantity["Fathoms"] |
Feet | Quantity["Feet"] |
Fermi | Quantity["Fermis"] |
Foot | Quantity["Feet"] |
Furlong | Quantity["Furlongs"] |
Hand | Quantity["HandsUnit"] |
Inch | Quantity["Inches"] |
Kayser | Quantity["Kaysers"] |
League | Quantity["Leagues"] |
LightYear | Quantity["LightYears"] |
Link | Quantity["GuntersLinks"] |
Meter | Quantity["Meters"] |
Micron | Quantity["Microns"] |
Mil | Quantity["Mils"] |
Mile | Quantity["Miles"] |
NauticalMile | Quantity["NauticalMiles"] |
Parsec | Quantity["Parsecs"] |
Perch | Quantity["PerchesLength"] |
Pica | Quantity["Picas"] |
Pole | Quantity["Poles"] |
PrintersPoint | Quantity["DesktopPublishingPoints"] |
Rod | Quantity["Rods"] |
Rope | Quantity["Ropes"] |
Skein | Quantity["Skeins"] |
Stadion | Quantity["GreekStadions"] |
Stadium | Quantity["StadiaCommon"] |
StatuteMile | Quantity["Miles"] |
SurveyMile | Quantity["SurveyMiles"] |
XUnit | Quantity["XUnits"] |
Yard | Quantity["Yards"] |
Mass and Weight Units
Units` | Version 9 |
AMU | Quantity["AtomicMassUnit"] |
AssayTon | Quantity["AssayShortTons"] |
AtomicMassUnit | Quantity["AtomicMassUnit"] |
AvoirdupoisOunce | Quantity["Ounces"] |
AvoirdupoisPound | Quantity["Pounds"] |
Bale | Quantity["BalesOfCotton"] |
Carat | Quantity["Carats"] |
Cental | Quantity["Centals"] |
Dalton | Quantity["Daltons"] |
Drachma | Quantity["AtticDrachmes"] |
Geepound | Quantity["GeepoundsMass"] |
Grain | Quantity["Grains"] |
Gram | Quantity["Grams"] |
GrossHundredweight | Quantity["LongHundredweights"] |
Hundredweight | Quantity["LongHundredweights"] |
Kilogram | Quantity["Kilograms"] |
Libra | Quantity["RomanLibras"] |
LongTon | Quantity["LongTons"] |
MetricTon | Quantity["MetricTons"] |
Mina | Quantity["AtticMinas"] |
NetHundredweight | Quantity["ShortHundredweights"] |
Obolos | Quantity["AtticObols"] |
Ounce | Quantity["Ounces"] |
Pennyweight | Quantity["Pennyweights"] |
Pondus | Quantity["DutchPonds"] |
Pound | Quantity["Pounds"] |
Quintal | Quantity["Quintals"] |
Shekel | Quantity["ShekelsMass"] |
ShortHundredweight | Quantity["ShortHundredweights"] |
ShortTon | Quantity["ShortTons"] |
Slug | Quantity["SlugsMass"] |
SolarMass | Quantity["SolarMass"] |
Stone | Quantity["Stones"] |
Talent | Quantity["GreekTalents"] |
Ton | Quantity["ShortTons"] |
Tonne | Quantity["MetricTons"] |
TroyOunce | Quantity["TroyOunces"] |
Temperature Units
Units` | Version 9 |
Celsius | Quantity["DegreesCelsius"] Quantity["DegreesCelsiusDifference"] |
Centigrade | Quantity["DegreesCelsius"] Quantity["DegreesCelsiusDifference"] |
Fahrenheit | Quantity["DegreesFahrenheit"] Quantity["DegreesFahrenheitDifference"] |
Kelvin | Quantity["Kelvins"] Quantity["KelvinsDifference"] |
Rankine | Quantity["DegreesRankine"] Quantity["DegreesRankineDifference"] |
Temperature units include both absolute temperatures and temperature differences, which are treated as distinct units. For more information see the tutorial on temperature units.
Volume Units
Units` | Version 9 |
Bag | Quantity["BagsUS"] |
Barrel | Quantity["BarrelsOfOil"] |
BoardFoot | Quantity["BoardFeet"] |
Bucket | Quantity["BucketsUS"] |
Bushel | Quantity["BushelsUS"] |
Butt | Quantity["ButtsUS"] |
Cord | Quantity["Cords"] |
Ephah | Quantity["Ephahs"] |
Fifth | Quantity["Fifths"] |
Firkin | Quantity["FirkinsUS"] |
FluidDram | Quantity["FluidDrams"] |
FluidOunce | Quantity["FluidOunces"] |
Gallon | Quantity["Gallons"] |
Gill | Quantity["Gills"] |
Hogshead | Quantity["HogsheadsUS"] |
ImperialGallon | Quantity["GallonsUK"] |
ImperialPint | Quantity["PintsUK"] |
Jeroboam | Quantity["Jeroboams"] |
Jigger | Quantity["Jiggers"] |
Liter | Quantity["Liters"] |
Magnum | Quantity["Magnums"] |
Minim | Quantity["MinimsUS"] |
Noggin | Quantity["NogginsUS"] |
Omer | Quantity["Omers"] |
Peck | Quantity["Pecks"] |
Pint | Quantity["Pints"] |
Pony | Quantity["PoniesUS"] |
Puncheon | Quantity["PuncheonsUS"] |
Quart | Quantity["Quarts"] |
RegisterTon | Quantity["RegisterTon"] |
Seam | Quantity["SeamsUS"] |
Shot | Quantity["Shots"] |
Stere | Quantity["Steres"] |
Tablespoon | Quantity["Tablespoons"] |
Teaspoon | Quantity["Teaspoons"] |
Tun | Quantity["Tuns"] |
UKGallon | Quantity["GallonsUK"] |
UKPint | Quantity["PintsUK"] |
WineBottle | Quantity["WineBottle750Milliliter"] |
Area Units
Units` | Version 9 |
Acre | Quantity["Acres"] |
Are | Quantity["Ares"] |
Barn | Quantity["Barns"] |
Hectare | Quantity["Hectares"] |
Rood | Quantity["ScottishRods"] |
Section | Quantity["SectionsArea"] |
Township | Quantity["Townships"] |
Time Units
Units` | Version 9 |
Century | Quantity["Centuries"] |
Day | Quantity["Days"] |
Decade | Quantity["Decades"] |
Fortnight | Quantity["Fortnights"] |
Hour | Quantity["Hours"] |
Millennium | Quantity["Millennia"] |
Minute | Quantity["Minutes"] |
Month | Quantity["Months"] |
Second | Quantity["Seconds"] |
SiderealSecond | Quantity["SiderealSeconds"] |
SiderealYear | Quantity["SiderealYears"] |
TropicalYear | Quantity["TropicalYears"] |
Week | Quantity["Weeks"] |
Year | Quantity["Years"] |
Force, Energy, and Power Units
Units` | Version 9 |
BritishThermalUnit | Quantity["BritishThermalUnitsIT"] |
BTU | Quantity["BritishThermalUnitsIT"] |
Calorie | Quantity["LargeCalories"] |
ChevalVapeur | Quantity["ChevalVapeurs"] |
Dyne | Quantity["Dynes"] |
ElectronVolt | Quantity["Electronvolts"] |
Erg | Quantity["Ergs"] |
GramWeight | Quantity["GramsForce"] |
Horsepower | Quantity["HorsepowerMechanical"] |
Joule | Quantity["Joules"] |
KilogramForce | Quantity["KilogramsForce"] |
KilogramWeight | Quantity["KilogramWeight"] |
Newton | Quantity["Newtons"] |
Poundal | Quantity["Poundals"] |
PoundForce | Quantity["PoundsForce"] |
PoundWeight | Quantity["PoundsForce"] |
Rydberg | Quantity["Rydbergs"] |
Therm | Quantity["Therms"] |
TonForce | Quantity["LongTonsForce"] |
Watt | Quantity["Watts"] |
Pressure Units
Units` | Version 9 |
Atmosphere | Quantity["Atmospheres"] |
Bar | Quantity["Bars"] |
Barye | Quantity["Baryes"] |
InchMercury | Quantity["InchesOfMercury"] |
MillimeterMercury | Quantity["MillimetersOfMercury"] |
Pascal | Quantity["Pascals"] |
PoundsPerSquareInch | Quantity["PoundsForce"/"Inches"^2] |
PSI | Quantity["PoundsForce"/"Inches"^2] |
Torr | Quantity["Torr"] |
Electromagnetism Units
Units` | Version 9 |
Abampere | Quantity["ABAmperes"] |
Abcoulomb | Quantity["ABCoulombs"] |
Abfarad | Quantity["ABFarads"] |
Abhenry | Quantity["ABHenries"] |
Abmho | Quantity["ABMhos"] |
Abohm | Quantity["ABOhms"] |
Abvolt | Quantity["ABVolts"] |
Amp | Quantity["Amperes"] |
Ampere | Quantity["Amperes"] |
Biot | Quantity["Biots"] |
BohrMagneton | Quantity["BohrMagneton"] |
Coulomb | Quantity["Coulombs"] |
Farad | Quantity["Farads"] |
Gauss | Quantity["Gausses"] |
Gilbert | Quantity["Gilberts"] |
Henry | Quantity["Henries"] |
Maxwell | Quantity["Maxwells"] |
Mho | Quantity["Mhos"] |
NuclearMagneton | Quantity["NuclearMagnetons"] |
Oersted | Quantity["Oersteds"] |
Ohm | Quantity["Ohms"] |
Siemens | Quantity["Siemens"] |
Statampere | Quantity["StatAmperes"] |
Statcoulomb | Quantity["StatCoulombs"] |
Statfarad | Quantity["StatFarads"] |
Stathenry | Quantity["StatHenries"] |
Statohm | Quantity["StatOhms"] |
Statvolt | Quantity["StatVolts"] |
Tesla | Quantity["Teslas"] |
Volt | Quantity["Volts"] |
Weber | Quantity["Webers"] |
Illumination Units
Units` | Version 9 |
Apostilb | Quantity["Apostilbs"] |
Candela | Quantity["Candelas"] |
Candle | Quantity["Candle"] |
FootCandle | Quantity["FootCandle"] |
Hefner | Quantity["HefnerKerzen"] |
Lambert | Quantity["Lamberts"] |
Lumerg | Quantity["Lumergs"] |
Lumen | Quantity["Lumens"] |
Lux | Quantity["Lux"] |
Nit | Quantity["Nits"] |
Phot | Quantity["Phots"] |
Stilb | Quantity["Stilbs"] |
Talbot | Quantity["Talbots"] |
Information Units
Units` | Version 9 |
Baud | Quantity["Bits"/"Seconds"] |
Bit | Quantity["Bits"] |
Nibble | Quantity["Nibbles"] |
Radiation Units
Units` | Version 9 |
Becquerel | Quantity["Becquerels"] |
Curie | Quantity["Curies"] |
GrayDose | Quantity["Grays"] |
Rad | Quantity["Rads"] |
Roentgen | Quantity["Roentgens"] |
Rontgen | Quantity["Roentgens"] |
Rutherford | Quantity["Rutherfords"] |
Viscosity Units
Units` | Version 9 |
Poise | Quantity["Poise"] |
Reyn | Quantity["Reyns"] |
Rhes | Quantity["Rhes"] |
Stokes | Quantity["Stokes"] |
Unit Multipliers
Units` | Version 9 |
ArcMinute | Quantity["ArcMinutes"] |
ArcSecond | Quantity["ArcSeconds"] |
BakersDozen | Quantity["BakersDozens"] |
Dozen | Quantity["Dozens"] |
Grade | Quantity["Grads"] |
Gross | Quantity["Grosses"] |
Percent | Quantity["Percent"] |
Quadrant | Quantity[π/2,"Radians"] |
RightAngle | Quantity["RightAngles"] |
Other Units
Units` | Version 9 |
Denier | Quantity["Denier"] |
Gal | Quantity["Galileos"] |
Gravity | Quantity["StandardAccelerationOfGravity"] |
Hertz | Quantity["Hertz"] |
Knot | Quantity["Knots"] |
Mole | Quantity["Moles"] |
Radian | Quantity["Radians"] |
Steradian | Quantity["Steradians"] |
Note especially that the units in the kernel are expressed as strings in plural form.
Unitless forms for dimensionless units can be derived with 1 as the unit.
Some of the values from the previous conversions will be slightly different from the old package. In some cases, this is the result of updated scientific research. (The Hubble constant can be considered an example of this.) In others, a slightly different standard was used for deriving the value, as in the case of the speed of sound in air. Finally, the so-called solar constant (and associated solar luminosity) provides an exception, as it is not in fact constant, and the current value more correctly reflects the solar cycle.