Class

UnitDispersion

A unit of measure for an amount-of-substance fraction.

Declaration

class UnitDispersion : Dimension

Overview

You typically use instances of NSUnitDispersion to represent specific quantities of dispersion using the NSMeasurement class.

Dispersion

Dispersion describes the the amount of a constituent divided by the amount of all other constituents in a mixture. Dispersion is a dimensionless quantity that is commonly expressed in “parts-per” notation, such as “parts per million” (ppm), to describe small relative quantities.

The NSUnitDispersion class defines its base unit as partsPerMillion.

Name

Method

Abbreviation

Parts Per Million

partsPerMillion

ppm

Topics

Accessing Predefined Units

class var partsPerMillion: UnitDispersion

Returns the parts per million unit.

Relationships

Inherits From

See Also

Concentration and Dispersion

class UnitConcentrationMass

A unit of measure for concentration of mass.

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