SIDimensionality

Interface for representing and manipulating SI physical dimensionalities.

The SIDimensionality API provides an immutable interface for physical dimensionalities, supporting all seven SI base dimensions: length, mass, time, electric current, temperature, amount of substance, and luminous intensity. Dimensionalities may be combined, reduced, raised to powers, parsed from strings, and tested for equality or compatibility.

Defines

kSIQuantityDimensionless

kSIQuantityLength

kSIQuantityInverseLength

kSIQuantityWavenumber

kSIQuantityLengthRatio

kSIQuantityPlaneAngle

kSIQuantityMass

kSIQuantityInverseMass

kSIQuantityMassRatio

kSIQuantityTime

kSIQuantityInverseTime

kSIQuantityFrequency

kSIQuantityRadioactivity

kSIQuantityTimeRatio

kSIQuantityFrequencyRatio

kSIQuantityInverseTimeSquared

kSIQuantityCurrent

kSIQuantityInverseCurrent

kSIQuantityCurrentRatio

kSIQuantityTemperature

kSIQuantityInverseTemperature

kSIQuantityTemperatureRatio

kSIQuantityTemperatureGradient

kSIQuantityAmount

kSIQuantityInverseAmount

kSIQuantityAmountRatio

kSIQuantityLuminousIntensity

kSIQuantityInverseLuminousIntensity

kSIQuantityLuminousIntensityRatio

kSIQuantityArea

kSIQuantityInverseArea

kSIQuantityAreaRatio

kSIQuantitySolidAngle

kSIQuantityVolume

kSIQuantityInverseVolume

kSIQuantityVolumeRatio

kSIQuantitySpeed

kSIQuantityVelocity

kSIQuantityLinearMomentum

kSIQuantityAngularMomentum

kSIQuantityMomentOfInertia

kSIQuantityAcceleration

kSIQuantityMassFlowRate

kSIQuantityMassFlux

kSIQuantityDensity

kSIQuantitySpecificGravity

kSIQuantitySpecificSurfaceArea

kSIQuantitySurfaceAreaToVolumeRatio

kSIQuantitySurfaceDensity

kSIQuantitySpecificVolume

kSIQuantityCurrentDensity

kSIQuantityMagneticFieldStrength

kSIQuantityLuminance

kSIQuantityRefractiveIndex

kSIQuantityFluidity

kSIQuantityMomentOfForce

kSIQuantitySurfaceTension

kSIQuantitySurfaceEnergy

kSIQuantityAngularSpeed

kSIQuantityAngularVelocity

kSIQuantityAngularAcceleration

kSIQuantityHeatFluxDensity

kSIQuantityIrradiance

kSIQuantitySpectralRadiantFluxDensity

kSIQuantityHeatCapacity

kSIQuantityEntropy

kSIQuantitySpecificHeatCapacity

kSIQuantitySpecificEntropy

kSIQuantitySpecificEnergy

kSIQuantityThermalConductance

kSIQuantityThermalConductivity

kSIQuantityEnergyDensity

kSIQuantityElectricFieldStrength

kSIQuantityElectricFieldGradient

kSIQuantityElectricChargeDensity

kSIQuantitySurfaceChargeDensity

kSIQuantityElectricFlux

kSIQuantityElectricFluxDensity

kSIQuantityElectricDisplacement

kSIQuantityPermittivity

kSIQuantityPermeability

kSIQuantityMolarEnergy

kSIQuantityMolarEntropy

kSIQuantityMolarHeatCapacity

kSIQuantityMolarMass

kSIQuantityMolality

kSIQuantityDiffusionFlux

kSIQuantityMassToChargeRatio

kSIQuantityChargeToMassRatio

kSIQuantityRadiationExposure

kSIQuantityAbsorbedDoseRate

kSIQuantityRadiantIntensity

kSIQuantitySpectralRadiantIntensity

kSIQuantityRadiance

kSIQuantitySpectralRadiance

kSIQuantityPorosity

kSIQuantityAngularFrequency

kSIQuantityForce

kSIQuantityTorque

kSIQuantityPressure

kSIQuantityStress

kSIQuantityElasticModulus

kSIQuantityCompressibility

kSIQuantityStressOpticCoefficient

kSIQuantityPressureGradient

kSIQuantityEnergy

kSIQuantitySpectralRadiantEnergy

kSIQuantityPower

kSIQuantitySpectralPower

kSIQuantityVolumePowerDensity

kSIQuantitySpecificPower

kSIQuantityRadiantFlux

kSIQuantityElectricCharge

kSIQuantityAmountOfElectricity

kSIQuantityElectricPotentialDifference

kSIQuantityElectromotiveForce

kSIQuantityElectricPolarizability

kSIQuantityElectricDipoleMoment

kSIQuantityVoltage

kSIQuantityCapacitance

kSIQuantityElectricResistance

kSIQuantityElectricResistancePerLength

kSIQuantityElectricResistivity

kSIQuantityElectricConductance

kSIQuantityElectricConductivity

kSIQuantityElectricalMobility

kSIQuantityMolarConductivity

kSIQuantityMagneticDipoleMoment

kSIQuantityMagneticDipoleMomentRatio

kSIQuantityMagneticFlux

kSIQuantityMagneticFluxDensity

kSIQuantityMolarMagneticSusceptibility

kSIQuantityInverseMagneticFluxDensity

kSIQuantityMagneticFieldGradient

kSIQuantityInductance

kSIQuantityLuminousFlux

kSIQuantityLuminousFluxDensity

kSIQuantityLuminousEnergy

kSIQuantityIlluminance

kSIQuantityAbsorbedDose

kSIQuantityDoseEquivalent

kSIQuantityCatalyticActivity

kSIQuantityCatalyticActivityConcentration

kSIQuantityCatalyticActivityContent

kSIQuantityAction

kSIQuantityReducedAction

kSIQuantityKinematicViscosity

kSIQuantityDiffusionCoefficient

kSIQuantityCirculation

kSIQuantityDynamicViscosity

kSIQuantityAmountConcentration

kSIQuantityMassConcentration

kSIQuantityChargePerAmount

kSIQuantityGravitationalConstant

kSIQuantityLengthPerVolume

kSIQuantityVolumePerLength

kSIQuantityVolumetricFlowRate

kSIQuantityFrequencyPerMagneticFluxDensity

kSIQuantityPowerPerLuminousFlux

kSIQuantityLuminousEfficacy

kSIQuantityRockPermeability

kSIQuantityGyromagneticRatio

kSIQuantityHeatTransferCoefficient

kSIQuantityGasPermeance

kSIQuantityPowerPerAreaPerTemperatureToFourthPower

kSIQuantityFirstHyperPolarizability

kSIQuantitySecondHyperPolarizability

kSIQuantityElectricQuadrupoleMoment

kSIQuantityMagnetizability

kSIQuantitySecondRadiationConstant

kSIQuantityWavelengthDisplacementConstant

kSIQuantityFineStructureConstant

kSIQuantityRatePerAmountConcentrationPerTime

Functions

SIDimensionalityRef SIDimensionalityFromExpression(OCStringRef expression, OCStringRef *error): Parse an SI dimensionality expression into a cached, immutable object.

OCTypeID SIDimensionalityGetTypeID(void): Returns the unique type identifier for SIDimensionality objects.

OCStringRef SIDimensionalityCopySymbol(SIDimensionalityRef theDim): Gets the canonical symbol representation of a dimensionality.

uint8_t SIDimensionalityGetNumExpAtIndex(SIDimensionalityRef theDim, SIBaseDimensionIndex index): Gets the numerator of the rational exponent for a base dimension.

uint8_t SIDimensionalityGetDenExpAtIndex(SIDimensionalityRef theDim, SIBaseDimensionIndex index): Gets the denominator of the rational exponent for a base dimension.

int8_t SIDimensionalityReducedExponentAtIndex(SIDimensionalityRef theDim, SIBaseDimensionIndex index): Gets the reduced exponent (num - den) for a base dimension.

cJSON *SIDimensionalityCopyAsJSON(SIDimensionalityRef dim, bool typed, OCStringRef *outError)

Create a JSON representation of an SIDimensionality.

Creates either a typed or untyped JSON representation based on the typed parameter.

Typed: {“type”: “SIDimensionality”, “value”: “m/s^2”}
Untyped: “m/s^2”

Parameters:

dim – An SIDimensionalityRef instance.
typed – If true, creates a typed JSON object. If false, creates a plain string.
outError – Optional pointer to receive error information if serialization fails.

Returns:

A cJSON object or string, or cJSON null on failure.

SIDimensionalityRef SIDimensionalityFromJSON(cJSON *json, OCStringRef *outError)

Create an SIDimensionality object from a JSON representation.

Accepts both typed and untyped JSON formats:

Typed: {“type”: “SIDimensionality”, “value”: “m/s^2”}
Untyped: “m/s^2”

Parameters:

json – A cJSON object or string representing the dimensionality.

Returns:

An SIDimensionalityRef or NULL on failure.

bool SIDimensionalityEqual(SIDimensionalityRef theDim1, SIDimensionalityRef theDim2): Returns true if two dimensionalities are strictly equal.

bool SIDimensionalityIsDimensionless(SIDimensionalityRef theDim): Returns true if dimensionality is physically dimensionless.

bool SIDimensionalityIsDerived(SIDimensionalityRef theDim): Returns true if dimensionality is derived.

bool SIDimensionalityIsDimensionlessAndNotDerived(SIDimensionalityRef theDim): Returns true if dimensionless and not derived by cancellation.

bool SIDimensionalityIsDimensionlessAndDerived(SIDimensionalityRef theDim): Returns true if dimensionless by cancellation of base symbols.

bool SIDimensionalityIsBaseDimensionality(SIDimensionalityRef theDim): Returns true if dimensionality matches exactly one SI base dimension.

bool SIDimensionalityHasSameReducedDimensionality(SIDimensionalityRef theDim1, SIDimensionalityRef theDim2): Returns true if two dimensionalities have the same reduced exponents.

bool SIDimensionalityHasReducedExponents(SIDimensionalityRef theDim, int8_t length_exponent, int8_t mass_exponent, int8_t time_exponent, int8_t current_exponent, int8_t temperature_exponent, int8_t amount_exponent, int8_t luminous_intensity_exponent): Returns true if dimensionality has the specified reduced exponents.

bool SIDimensionalityCanBeReduced(SIDimensionalityRef theDim): Returns true if dimensionality can be reduced by canceling common factors.

SIDimensionalityRef SIDimensionalityDimensionless(void): Returns the canonical dimensionless dimensionality.

SIDimensionalityRef SIDimensionalityForBaseDimensionIndex(SIBaseDimensionIndex index): Returns the dimensionality for a given base dimension index.

SIDimensionalityRef SIDimensionalityWithBaseDimensionSymbol(OCStringRef symbol, OCStringRef *error): Returns the dimensionality for a single-character base symbol.

SIDimensionalityRef SIDimensionalityForQuantity(OCStringRef quantity, OCStringRef *error): Maps a quantity name to its dimensionality.

SIDimensionalityRef SIDimensionalityByReducing(SIDimensionalityRef theDimensionality): Returns a dimensionality with all exponents reduced to lowest terms.

SIDimensionalityRef SIDimensionalityByTakingNthRoot(SIDimensionalityRef theDim, uint8_t root, OCStringRef *error): Returns the nth-root of a dimensionality, or NULL and error if invalid.

SIDimensionalityRef SIDimensionalityByMultiplying(SIDimensionalityRef theDim1, SIDimensionalityRef theDim2): Multiplies two dimensionalities and reduces to lowest terms.

SIDimensionalityRef SIDimensionalityByMultiplyingWithoutReducing(SIDimensionalityRef theDim1, SIDimensionalityRef theDim2): Multiplies two dimensionalities without reducing exponents.

SIDimensionalityRef SIDimensionalityByDividing(SIDimensionalityRef theDim1, SIDimensionalityRef theDim2): Divides one dimensionality by another, reduces result.

SIDimensionalityRef SIDimensionalityByDividingWithoutReducing(SIDimensionalityRef theDim1, SIDimensionalityRef theDim2): Divides one dimensionality by another, does not reduce exponents.

SIDimensionalityRef SIDimensionalityByRaisingToPower(SIDimensionalityRef theDim, int power): Create a new dimensionality by raising to a power and reducing exponents to lowest terms.

SIDimensionalityRef SIDimensionalityByRaisingToPowerWithoutReducing(SIDimensionalityRef theDim, int power): Create a new dimensionality by raising to a power without reducing exponents.

OCArrayRef SIDimensionalityCreateArrayOfQuantities(SIDimensionalityRef theDim): Returns all quantity names matching this dimensionality exactly.

OCArrayRef SIDimensionalityCreateArrayOfQuantitiesWithSameReducedDimensionality(SIDimensionalityRef theDim): Returns all quantity names with the same reduced dimensionality.

OCArrayRef SIDimensionalityCreateArrayWithSameReducedDimensionality(SIDimensionalityRef theDim): Returns all built-in dimensionalities with the same reduced dimensionality.

OCArrayRef SIDimensionalityCreateArrayOfQuantityNames(SIDimensionalityRef dim): Returns an array of quantity names mapped to the given dimensionality.

OCArrayRef SIDimensionalityCreateArrayOfQuantityNamesWithSameReducedDimensionality(SIDimensionalityRef dim): Returns all quantity names associated with dimensionalities that reduce to the same form as the input.

OCArrayRef SIDimensionalityCreateArrayOfAllQuantityNames(void): Returns an array of all available quantity names in the library.

void SIDimensionalityShow(SIDimensionalityRef theDim): Prints a concise representation of the dimensionality to stdout.

void SIDimensionalityShowFull(SIDimensionalityRef theDim): Prints a detailed, annotated report of the dimensionality to stdout.