Units of Measurement API 0.6-SNAPSHOT API

Specifies Java packages for the programmatic, type safe handling of quantities and their expression as numbers of units.

See:
Description

Packages

org.unitsofmeasurement.quantity	Provides quantitative properties such as mass, time, distance, heat, and angular separation.
org.unitsofmeasurement.service	Provides services for units, quantities or their textual representation.
org.unitsofmeasurement.unit	Specifies Java packages for the programmatic, type safe handling of quantities and their expression as numbers of units.

Specifies Java packages for the programmatic, type safe handling of quantities and their expression as numbers of units. The core interfaces of this API are Unit and Quantity.

Definition of terms

This API adopts the definitions provided by the International Vocabulary of Metrology (VIM), with some adaptations:

• Quantity: property of a phenomenon, body, or substance, where the property has a magnitude that can be expressed as a number and a unit.
  (Change compared to VIM: the term "reference" has been restricted to "unit")

• Kind of quantity: aspect common to mutually comparable quantities.

• Dimension: expression of the dependence of a unit on the base units of a system of units as a product of powers of dimensions corresponding to the base units, omitting any numerical factor.
  (Change compared to VIM: replaced "quantity" terms by "unit", because dimensions are associated to units in this API)

• Dimensionless: quantity for which all exponents of the dimensions corresponding to the base units are zero.
  (Change compared to VIM: replaced "factors" terms by "dimensions")

• Unit: real scalar quantity, defined and adopted by convention, with which any other quantity of the same kind can be compared to express the ratio of the two quantities as a number.

• Base unit: unit in a conventionally chosen subset of a given system of units, where no subset unit can be expressed in terms of the others.
  (Change compared to VIM: replaced "quantity" terms by "unit", because dimensions are associated to units in this API)

• System of units: set of base units and derived units, together with their multiples and submultiples, defined in accordance with given rules.
  (Change compared to VIM: omitted the reference to the system of quantities)

Links

• Units of Measurement project home page
• International Vocabulary of Metrology (VIM)