Quantities, units and computing

Quantities and units are concepts central to our measurement and manipulation of the physical world, but their representation in information systems is barely codified and often ignored. The lack of formalization of metrological concepts, operations, symbols and characters has resulted in multiple reinvention (or more dangerously, omission) of these entities in informatics systems. At best, this creates ambiguity and inconvenience; at worst, the potential for an engineering disaster. The computer representation of quantities and SI units is reviewed at these four levels. Three implementations (languages, calculators and sensor data transfer) supporting units of measure are examined. Some suggestions for a hierarchy of metrological-informatics standards are given.

► The representation of quantities and units in computer systems is barely codified.
► This is reviewed at the character, symbolic, operational and semantic levels.
► Languages, calculators and sensor software which support units, are examined.
► A suggested hierarchy of metrological-informatics standards is given.