quantity_si library
The core library containing the fundamental quantity classes and types consistent with the International System of Units (SI, in the French acronym).
Classes
 AbsorbedDose
 The mean energy imparted to matter per unit mass by ionizing radiation. See the Wikipedia entry for Absorbed Dose for more information.
 AbsorbedDoseRate
 The rate of mean energy imparted to matter per unit mass by ionizing radiation. See the Wikipedia entry for Absorbed Dose for more information.
 AbsorbedDoseRateUnits
 Units acceptable for use in describing AbsorbedDoseRate quantities.
 AbsorbedDoseUnits
 Units acceptable for use in describing AbsorbedDose quantities.
 Acceleration
 The rate of change of speed of an object. See the Wikipedia entry for Acceleration for more information.
 AccelerationUnits
 Units acceptable for use in describing Acceleration quantities.
 Activity
 A measure of the effective concentration of a species in a mixture. See the Wikipedia entry for Thermodynamic activity for more information.
 ActivityUnits
 Units acceptable for use in describing Activity quantities.
 AmountOfSubstance
 The size of an ensemble of elementary entities, such as atoms, molecules, electrons, and other particles. See the Wikipedia entry for Amount of substance for more information.
 AmountOfSubstanceUnits
 Units acceptable for use in describing AmountOfSubstance quantities.
 Angle
 A planar (2dimensional) angle, which has dimensions of 1 and is a measure of the ratio of the length of a circular arc to its radius.
 AngleUnits
 Units acceptable for use in describing Angle quantities.
 AngularAcceleration
 The rate of change of angular speed. See the Wikipedia entry for Angular acceleration for more information.
 AngularAccelerationUnits
 Units acceptable for use in describing AngularAcceleration quantities.
 AngularMomentum
 A measure of the quantity of rotation of a system of matter, taking into account its mass, rotations, motions and shape. See the Wikipedia entry for Angular momentum for more information.
 AngularMomentumUnits
 Units acceptable for use in describing AngularMomentum quantities.
 AngularSpeed
 The rate of change of an angle. See the Wikipedia entry for Angular_velocity for more information.
 AngularSpeedUnits
 Units acceptable for use in describing AngularSpeed quantities.
 Area
 The extent of a twodimensional figure or shape. See the Wikipedia entry for Area for more information.
 AreaUnits
 Units acceptable for use in describing Area quantities.
 Capacitance
 The ability of a body to store an electrical charge, See the Wikipedia entry for Capacitance for more information.
 CapacitanceUnits
 Units acceptable for use in describing Capacitance quantities.
 CatalyticActivity
 The increase in rate of a chemical reaction caused by the presence of a catalyst. See the Wikipedia entry for Catalysis for more information.
 CatalyticActivityUnits
 Units acceptable for use in describing CatalyticActivity quantities.
 Charge
 The property of matter that causes it to experience a force when placed in an electromagnetic field See the Wikipedia entry for Electric charge for more information.
 ChargeDensity
 Electric charge per unit volume of space. See the Wikipedia entry for Charge density for more information.
 ChargeDensityUnits
 Units acceptable for use in describing ChargeDensity quantities.
 ChargeUnits
 Units acceptable for use in describing Charge quantities.
 Concentration
 The abundance of a constituent divided by the total volume of a mixture. See the Wikipedia entry for Concentration for more information.
 ConcentrationUnits
 Units acceptable for use in describing Concentration quantities.
 Conductance

The ease with which an electric current passes through a conductor (the inverse of
Resistance
). See the Wikipedia entry for Electrical resistance and conductance for more information.  ConductanceUnits
 Units acceptable for use in describing Conductance quantities.
 Currency
 Money in any form when in actual use or circulation as a medium of exchange. See the Wikipedia entry for Currency for more information.
 CurrencyUnits
 Units acceptable for use in describing Currency quantities.
 Current
 The flow of electric charge. See the Wikipedia entry for Electric current for more information.
 CurrentDensity
 The electric current per unit area of cross section. See the Wikipedia entry for Current density for more information.
 CurrentDensityUnits
 Units acceptable for use in describing CurrentDensity quantities.
 CurrentUnits
 Units acceptable for use in describing Current quantities.
 Dimensions
 The Dimensions class represents the dimensions of a physical quantity.
 DoseEquivalent
 Represents the stochastic health effects (probability of cancer induction and genetic damage) of ionizing radiation on the human body. See the Wikipedia entry for Equivalent dose for more information.
 DoseEquivalentUnits
 Units acceptable for use in describing DoseEquivalent quantities.
 DynamicViscosity
 A measure of a fluid's resistance to gradual deformation by shear stress or tensile stress. See the Wikipedia entry for Viscosity for more information.
 DynamicViscosityUnits
 Units acceptable for use in describing DynamicViscosity quantities.
 ElectricFieldStrength
 The magnitude of the force per unit charge that an electric field exerts. See the Wikipedia entry for Electric field for more information.
 ElectricFieldStrengthUnits
 Units acceptable for use in describing ElectricFieldStrength quantities.
 ElectricFluxDensity
 A measure of the intensity of an electric field generated by a free electric charge, corresponding to the number of electric field lines passing through a given area. See the Wikipedia entry for Electric_flux for more information.
 ElectricFluxDensityUnits
 Units acceptable for use in describing ElectricFluxDensity quantities.
 ElectricPotentialDifference
 The difference in electric potential energy between two points per unit electric charge See the Wikipedia entry for Voltage for more information.
 ElectricPotentialDifferenceUnits
 Units acceptable for use in describing ElectricPotentialDifference quantities.
 Energy
 The ability of a system to perform work; cannot be created or destroyed but can take many forms. See the Wikipedia entry for Energy for more information.
 EnergyDensity
 The amount of energy stored in a given system or region of space per unit volume. See the Wikipedia entry for Energy density for more information.
 EnergyDensityUnits
 Units acceptable for use in describing EnergyDensity quantities.
 EnergyFlux
 The rate of transfer of energy through a surface. See the Wikipedia entry for Energy density for more information.
 EnergyFluxUnits
 Units acceptable for use in describing EnergyFlux quantities.
 EnergyUnits
 Units acceptable for use in describing Energy quantities.
 EngineeringFormatSI
 A version of scientific notation in which the exponent of ten must be divisible by three (e.g., 123.345 x 10^3).
 Entropy
 The number of specific ways in which a thermodynamic system may be arranged, commonly understood as a measure of disorder. See the Wikipedia entry for Entropy for more information.
 EntropyUnits
 Units acceptable for use in describing Entropy quantities.
 Exposure
 The radiant energy received by a surface per unit area. See the Wikipedia entry for Radiant exposure for more information.
 ExposureUnits
 Units acceptable for use in describing Exposure quantities.
 FieldLevel
 Represents a level of a field quantity, a logarithmic quantity. Level of a field quantity is defined as ln(F/F0), where F/F0 is the ratio of two field quantities and F0 is a reference amplitude of the appropriate type.
 Force
 Any interaction that, when unopposed, changes the motion of an object. See the Wikipedia entry for Force for more information.
 ForceUnits
 Units acceptable for use in describing Force quantities.
 Frequency
 The number of occurrences of a repeating event per unit time. See the Wikipedia entry for Frequency for more information.
 FrequencyUnits
 Units acceptable for use in describing Frequency quantities.
 HeatFluxDensity
 Heat rate per unit area. See the Wikipedia entry for Heat flux for more information.
 HeatFluxDensityUnits
 Units acceptable for use in describing HeatFluxDensity quantities.
 Illuminance
 The total luminous flux incident on a surface, per unit area. See the Wikipedia entry for Illuminance for more information.
 IlluminanceUnits
 Units acceptable for use in describing Illuminance quantities.
 Inductance
 The property of an electrical conductor by which a change in current flowing through it induces an electromotive force in both the conductor itself and in any nearby conductors by mutual inductance. See the Wikipedia entry for Inductance for more information.
 InductanceUnits
 Units acceptable for use in describing Inductance quantities.
 Information
 Amount of data. See the Wikipedia entry for Information for more information.
 InformationRate
 The flow of information, per unit time. See the Wikipedia entry for Information for more information.
 InformationRateUnits
 Units acceptable for use in describing InformationRate quantities.
 InformationUnits
 Units acceptable for use in describing Information quantities.
 KinematicViscosity
 The resistance to flow of a fluid, equal to its absolute viscosity divided by its density. See the Wikipedia entry for Viscosity for more information.
 KinematicViscosityUnits
 Units acceptable for use in describing KinematicViscosity quantities.
 Length
 Represents the length physical quantity (one of the seven base SI quantities). See the Wikipedia entry for Length for more information.
 LengthUnits
 Units acceptable for use in describing Length quantities.
 Level
 Represents logarithmic physical quantities and has dimensions of 1 (Scalar). Level of a field quantity and level of a power quantity are two common logarithmic quantities.
 LevelUnits
 Units acceptable for use in describing Level quantities.
 Luminance
 The intensity of light emitted from a surface per unit area. See the Wikipedia entry for Luminance for more information.
 LuminanceUnits
 Units acceptable for use in describing Luminance quantities.
 LuminousFlux
 The perceived power of light. It differs from radiant flux, the measure of the total power of electromagnetic radiation (including infrared, ultraviolet, and visible light), in that luminous flux is adjusted to reflect the varying sensitivity of the human eye to different wavelengths of light See the Wikipedia entry for Luminance for more information.
 LuminousFluxUnits
 Units acceptable for use in describing LuminousFlux quantities.
 LuminousIntensity
 Represents the luminous intensity physical quantity (one of the seven base SI quantities), the wavelengthweighted power emitted by a light source in a particular direction per unit solid angle. See the Wikipedia entry for Luminous intensity for more information.
 LuminousIntensityUnits
 Units acceptable for use in describing LuminousIntensity quantities.
 MagneticFieldStrength
 The intensity of a magnetic field. See the Wikipedia entry for Magnetic field for more information.
 MagneticFieldStrengthUnits
 Units acceptable for use in describing MagneticFieldStrength quantities.
 MagneticFlux
 The magnetic flux density passing through a closed surface. See the Wikipedia entry for Magnetic flux for more information.
 MagneticFluxDensity
 The amount of magnetic flux in an area taken perpendicular to a magnetic flux's direction See the Wikipedia entry for Magnetic flux for more information.
 MagneticFluxDensityUnits
 Units acceptable for use in describing MagneticFluxDensity quantities.
 MagneticFluxUnits
 Units acceptable for use in describing MagneticFlux quantities.
 Mass
 Represents the mass physical quantity (one of the seven base SI quantities), that determines the strength of a body's mutual gravitational attraction to other bodies. See the Wikipedia entry for Mass for more information.
 MassDensity
 Mass per unit volume. See the Wikipedia entry for Density for more information.
 MassDensityUnits
 Units acceptable for use in describing MassDensity quantities.
 MassFlowRate
 The mass of a substance which passes per unit of time. See the Wikipedia entry for Mass flow rate for more information.
 MassFlowRateUnits
 Units acceptable for use in describing MassFlowRate quantities.
 MassFluxDensity
 The mass of a substance which passes per unit of time. See the Wikipedia entry for Mass flow rate for more information.
 MassFluxDensityUnits
 Units acceptable for use in describing MassFluxDensity quantities.
 MassUnits
 Units acceptable for use in describing Mass quantities.
 MiscQuantity
 A MiscQuantity is a general (miscellaneous) Quantity having arbitrary dimensions (including possibly the same dimensions as a named Quantity subclass). MiscQuantity objects may be used, for example, in less common domains or as intermediate results in equations.
 MolarEnergy
 Energy per mole of a substance. See the Wikipedia entry for Specific energy for more information.
 MolarEnergyUnits
 Units acceptable for use in describing MolarEnergy quantities.
 MolarEntropy
 Entropy content per mole of substance. See the Wikipedia entry for Standard molar entropy for more information.
 MolarEntropyUnits
 Units acceptable for use in describing MolarEntropy quantities.
 NumberFormatSI
 NumberFormatSI implements the International System of Units (SI) style conventions for displaying values of quantities. Specifically:
 Permeability
 The ability of a material to support the formation of a magnetic field within itself. See the Wikipedia entry for Permeability (electromagnetism) for more information.
 PermeabilityUnits
 Units acceptable for use in describing Permeability quantities.
 Permittivity
 The resistance that is encountered when forming an electric field in a medium. See the Wikipedia entry for Permittivity for more information.
 PermittivityUnits
 Units acceptable for use in describing Permittivity quantities.
 Power
 Amount of energy per unit time. See the Wikipedia entry for Power (physics) for more information.
 PowerLevel
 Represents a level of a power quantity, a logarithmic quantity. Level of a power quantity is defined as 0.5*ln(P/P0), where P/P0 is the ratio of two powers and P0 is a reference power.
 PowerUnits
 Units acceptable for use in describing Power quantities.
 Pressure
 Force applied perpendicular to the surface of an object per unit area over which that force is distributed. See the Wikipedia entry for Pressure for more information.
 PressureUnits
 Units acceptable for use in describing Pressure quantities.
 Quantity
 The abstract base class for all quantities. The Quantity class represents the value of a physical quantity and its associated dimensions. It provides methods for constructing and getting the quantity's value in arbitrary units, methods for mathematical manipulation and comparison and optional features such as arbitrary precision and uncertainty.
 Radiance
 The radiant flux emitted, reflected, transmitted or received by a surface, per unit solid angle per unit projected area. See the Wikipedia entry for Radiance for more information.
 RadianceUnits
 Units acceptable for use in describing Radiance quantities.
 RadiantFlux
 Radiant flux is another way to express power.
 RadiantIntensity
 The radiant flux emitted, reflected, transmitted or received, per unit solid angle. See the Wikipedia entry for Radiant intensity for more information.
 RadiantIntensityUnits
 Units acceptable for use in describing RadiantIntensity quantities.
 Resistance
 A measure of the difficulty passing an electric current through a conductor. See the Wikipedia entry for Electrical resistance and conductance for more information.
 ResistanceUnits
 Units acceptable for use in describing Resistance quantities.
 Scalar
 A onedimensional physical quantity that can be described by a single real number. See the Wikipedia entry for Scalar (physics) for more information.
 ScalarUnits
 Units acceptable for use in describing Scalar quantities.
 ScientificFormatSI
 Formats a number as a single integer digit, followed by decimal digits and raised to a power of 10 (e.g., 1.2345 x 10^3).
 SolidAngle
 A twodimensional angle in threedimensional space that an object subtends at a point. See the Wikipedia entry for Solid angle for more information.
 SolidAngleUnits
 Units acceptable for use in describing SolidAngle quantities.
 SpecificEnergy
 Energy per unit mass. See the Wikipedia entry for Specific energy for more information.
 SpecificEnergyUnits
 Units acceptable for use in describing SpecificEnergy quantities.
 SpecificHeatCapacity
 The heat capacity per unit mass of a material. See the Wikipedia entry for Heat capacity for more information.
 SpecificHeatCapacityUnits
 Units acceptable for use in describing SpecificHeatCapacity quantities.
 SpecificVolume
 The ratio of the substance's volume to its mass. See the Wikipedia entry for Specific volume for more information.
 SpecificVolumeUnits
 Units acceptable for use in describing SpecificVolume quantities.
 SpectralIrradiance
 Irradiance of a surface per unit frequency. See the Wikipedia entry for Radiometry for more information.
 SpectralIrradianceUnits
 Units acceptable for use in describing SpectralIrradiance quantities.
 Speed
 The rate of change of position. See the Wikipedia entry for Speed for more information.
 SpeedUnits
 Units acceptable for use in describing Speed quantities.
 SurfaceTension
 The elastic tendency of liquids which makes them acquire the least surface area possible. See the Wikipedia entry for Surface tension for more information.
 SurfaceTensionUnits
 Units acceptable for use in describing SurfaceTension quantities.
 Temperature
 An objective comparative measure of hot or cold. See the Wikipedia entry for Thermodynamic temperature for more information.
 TemperatureInterval
 The difference between two temperatures, where temperature is an objective comparative measure of hot or cold. See the Wikipedia entry for Thermodynamic temperature for more information.
 TemperatureIntervalUnits
 Units acceptable for use in describing TemperatureInterval quantities.
 TemperatureUnits
 Units acceptable for use in describing Temperature quantities.
 ThermalConductivity
 The ability of a material to conduct heat. See the Wikipedia entry for Thermal conductivity for more information.
 ThermalConductivityUnits
 Units acceptable for use in describing ThermalConductivity quantities.
 Time
 Represents the time interval physical quantity (one of the seven base SI quantities).
 TimeInstant

TimeInstant
represents a specific moment in time and its units enable conversion between various time scales.  TimeInstantUnits
 Units acceptable for use in describing TimeInstant quantities.
 TimeUnits
 Units acceptable for use in describing Time quantities.
 Torque
 The tendency of a force to rotate an object about an axis, fulcrum, or pivot. See the Wikipedia entry for Torque for more information.
 TorqueUnits
 Units acceptable for use in describing Torque quantities.
 Volume
 The amount of threedimensional space enclosed by some closed boundary. See the Wikipedia entry for Volume for more information.
 VolumeFlowRate
 The volume of fluid which passes per unit time. See the Wikipedia entry for Volumetric flow rate for more information.
 VolumeFlowRateUnits
 Units acceptable for use in describing VolumeFlowRate quantities.
 VolumeUnits
 Units acceptable for use in describing Volume quantities.
 WaveNumber
 The spatial frequency of a wave. See the Wikipedia entry for Wavenumber for more information.
 WaveNumberUnits
 Units acceptable for use in describing WaveNumber quantities.
Enums
 UncertaintyFormat
 Whether and how to display a quantity's uncertainty (e.g., compact is 32.324(12), not compact is (32.324 +/ 0.012)).
Mixins
 Units
 A unit is a particular physical quantity, defined and adopted by convention, with which other particular quantities of the same kind (dimensions) are compared to express their value.
Constants
Properties

allQuantityTypes
→ Iterable<
Type> 
Returns an iterable of Type objects representing all of the quantity types
supported by this library (for example, Angle, Length, etc.).
no setter
 dynamicQuantityTyping ↔ bool

Dynamic quantity typing may be turned off for increased
efficiency. If false, the result of operations where
dimensions may change will be MiscQuantity type objects.
getter/setter pair
 logger ↔ Logger

Logger for use across entire library
getter/setter pair
Functions

areWithin(
Quantity q1, Quantity q2, Quantity tolerance) → bool 
Returns whether or not the magnitude of the difference between two
quantities is less than or equal to the specified
tolerance
. 
cosine(
Angle a) → double  Calculates the cosine of an Angle (adjacent divided by hypotenuse).

createTypedQuantityInstance(
Type t, dynamic value, Units? units, {double uncert = 0.0, Dimensions? dimensions}) → Quantity 
Creates a instance of a typed quantity of type
t
having the specifiedvalue
inunits
. 
getDeltaT(
TimeInstant time) → double  Returns the value 'Delta T,' in seconds, which relates the Terrestrial Dynamical Time scale to measured Universal Time (and indirectly UTC to TAI before 1972, when leap seconds were introduced).

getLeapSeconds(
double tai, {bool pre1972LeapSeconds = false}) → num 
Returns the number of leap seconds in effect for the specified time
instant,
tai
, specified in the TAI time scale. The number of leap seconds relates the UTC time scale to the TAI time scale. 
secondsInUtcDay(
double utc) → double 
Calculates and returns the number of seconds (including any
leap seconds) that are in the UTC day containing the specified
second,
utc
. 
siBaseQuantity(
Quantity q) → bool 
Returns whether or not
q
is one of the seven SI base quantities. 
siDerivedQuantity(
Quantity q) → bool 
Returns whether or not
q
is a derived quantity (as opposed to one of the seven base SI quantities). 
sine(
Angle a) → double  Calculates the sine of an Angle (opposite divided by hypotenuse).

tangent(
Angle a) → double  Calculates the tangent of an Angle (opposite divided by adjacent).

unicodeExponent(
num exp) → String  Returns the unicode symbols that represent an exponent.
Typedefs
 FromMksOverride = Number Function(dynamic mks)
 ToMksOverride = Number Function(dynamic val)
Exceptions / Errors
 DimensionsException
 This Exception is thrown when an attempt is made to perform an operation on a Quantity having unexpected or illegal dimensions.
 ImmutableQuantityException
 This Exception is thrown when an attempt is made to modify an immutable Quantity object (for example through its setMKS method).
 QuantityException
 The base class for all exceptions thrown in relation to quantities.